Add parts of zxing library to generate qr codes

OpenPGP-Keychain/src/com/google/zxing/BarcodeFormat.java

@@ -0,0 +1,106 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+import java.util.Hashtable;
+
+/**
+ * Enumerates barcode formats known to this package. Please keep alphabetized.
+ *
+ * @author Sean Owen
+ */
+public final class BarcodeFormat {
+
+  // No, we can't use an enum here. J2ME doesn't support it.
+
+  private static final Hashtable VALUES = new Hashtable();
+
+  /** Aztec 2D barcode format. */
+  public static final BarcodeFormat AZTEC = new BarcodeFormat("AZTEC");
+
+  /** CODABAR 1D format. */
+  public static final BarcodeFormat CODABAR = new BarcodeFormat("CODABAR");
+
+  /** Code 39 1D format. */
+  public static final BarcodeFormat CODE_39 = new BarcodeFormat("CODE_39");
+
+  /** Code 93 1D format. */
+  public static final BarcodeFormat CODE_93 = new BarcodeFormat("CODE_93");
+
+  /** Code 128 1D format. */
+  public static final BarcodeFormat CODE_128 = new BarcodeFormat("CODE_128");
+
+  /** Data Matrix 2D barcode format. */
+  public static final BarcodeFormat DATA_MATRIX = new BarcodeFormat("DATA_MATRIX");
+
+  /** EAN-8 1D format. */
+  public static final BarcodeFormat EAN_8 = new BarcodeFormat("EAN_8");
+
+  /** EAN-13 1D format. */
+  public static final BarcodeFormat EAN_13 = new BarcodeFormat("EAN_13");
+
+  /** ITF (Interleaved Two of Five) 1D format. */
+  public static final BarcodeFormat ITF = new BarcodeFormat("ITF");
+
+  /** PDF417 format. */
+  public static final BarcodeFormat PDF_417 = new BarcodeFormat("PDF_417");
+
+  /** QR Code 2D barcode format. */
+  public static final BarcodeFormat QR_CODE = new BarcodeFormat("QR_CODE");
+
+  /** RSS 14 */
+  public static final BarcodeFormat RSS_14 = new BarcodeFormat("RSS_14");
+
+  /** RSS EXPANDED */
+  public static final BarcodeFormat RSS_EXPANDED = new BarcodeFormat("RSS_EXPANDED");
+
+  /** UPC-A 1D format. */
+  public static final BarcodeFormat UPC_A = new BarcodeFormat("UPC_A");
+
+  /** UPC-E 1D format. */
+  public static final BarcodeFormat UPC_E = new BarcodeFormat("UPC_E");
+
+  /** UPC/EAN extension format. Not a stand-alone format. */
+  public static final BarcodeFormat UPC_EAN_EXTENSION = new BarcodeFormat("UPC_EAN_EXTENSION");
+
+  private final String name;
+
+  private BarcodeFormat(String name) {
+    this.name = name;
+    VALUES.put(name, this);
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public String toString() {
+    return name;
+  }
+
+  public static BarcodeFormat valueOf(String name) {
+    if (name == null || name.length() == 0) {
+      throw new IllegalArgumentException();
+    }
+    BarcodeFormat format = (BarcodeFormat) VALUES.get(name);
+    if (format == null) {
+      throw new IllegalArgumentException();
+    }
+    return format;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/Binarizer.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+import com.google.zxing.common.BitArray;
+import com.google.zxing.common.BitMatrix;
+
+/**
+ * This class hierarchy provides a set of methods to convert luminance data to 1 bit data.
+ * It allows the algorithm to vary polymorphically, for example allowing a very expensive
+ * thresholding technique for servers and a fast one for mobile. It also permits the implementation
+ * to vary, e.g. a JNI version for Android and a Java fallback version for other platforms.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public abstract class Binarizer {
+
+  private final LuminanceSource source;
+
+  protected Binarizer(LuminanceSource source) {
+    if (source == null) {
+      throw new IllegalArgumentException("Source must be non-null.");
+    }
+    this.source = source;
+  }
+
+  public LuminanceSource getLuminanceSource() {
+    return source;
+  }
+
+  /**
+   * Converts one row of luminance data to 1 bit data. May actually do the conversion, or return
+   * cached data. Callers should assume this method is expensive and call it as seldom as possible.
+   * This method is intended for decoding 1D barcodes and may choose to apply sharpening.
+   * For callers which only examine one row of pixels at a time, the same BitArray should be reused
+   * and passed in with each call for performance. However it is legal to keep more than one row
+   * at a time if needed.
+   *
+   * @param y The row to fetch, 0 <= y < bitmap height.
+   * @param row An optional preallocated array. If null or too small, it will be ignored.
+   *            If used, the Binarizer will call BitArray.clear(). Always use the returned object.
+   * @return The array of bits for this row (true means black).
+   */
+  public abstract BitArray getBlackRow(int y, BitArray row) throws NotFoundException;
+
+  /**
+   * Converts a 2D array of luminance data to 1 bit data. As above, assume this method is expensive
+   * and do not call it repeatedly. This method is intended for decoding 2D barcodes and may or
+   * may not apply sharpening. Therefore, a row from this matrix may not be identical to one
+   * fetched using getBlackRow(), so don't mix and match between them.
+   *
+   * @return The 2D array of bits for the image (true means black).
+   */
+  public abstract BitMatrix getBlackMatrix() throws NotFoundException;
+
+  /**
+   * Creates a new object with the same type as this Binarizer implementation, but with pristine
+   * state. This is needed because Binarizer implementations may be stateful, e.g. keeping a cache
+   * of 1 bit data. See Effective Java for why we can't use Java's clone() method.
+   *
+   * @param source The LuminanceSource this Binarizer will operate on.
+   * @return A new concrete Binarizer implementation object.
+   */
+  public abstract Binarizer createBinarizer(LuminanceSource source);
+
+}

OpenPGP-Keychain/src/com/google/zxing/BinaryBitmap.java

@@ -0,0 +1,128 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+import com.google.zxing.common.BitArray;
+import com.google.zxing.common.BitMatrix;
+
+/**
+ * This class is the core bitmap class used by ZXing to represent 1 bit data. Reader objects
+ * accept a BinaryBitmap and attempt to decode it.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public final class BinaryBitmap {
+
+  private final Binarizer binarizer;
+  private BitMatrix matrix;
+
+  public BinaryBitmap(Binarizer binarizer) {
+    if (binarizer == null) {
+      throw new IllegalArgumentException("Binarizer must be non-null.");
+    }
+    this.binarizer = binarizer;
+    matrix = null;
+  }
+
+  /**
+   * @return The width of the bitmap.
+   */
+  public int getWidth() {
+    return binarizer.getLuminanceSource().getWidth();
+  }
+
+  /**
+   * @return The height of the bitmap.
+   */
+  public int getHeight() {
+    return binarizer.getLuminanceSource().getHeight();
+  }
+
+  /**
+   * Converts one row of luminance data to 1 bit data. May actually do the conversion, or return
+   * cached data. Callers should assume this method is expensive and call it as seldom as possible.
+   * This method is intended for decoding 1D barcodes and may choose to apply sharpening.
+   *
+   * @param y The row to fetch, 0 <= y < bitmap height.
+   * @param row An optional preallocated array. If null or too small, it will be ignored.
+   *            If used, the Binarizer will call BitArray.clear(). Always use the returned object.
+   * @return The array of bits for this row (true means black).
+   */
+  public BitArray getBlackRow(int y, BitArray row) throws NotFoundException {
+    return binarizer.getBlackRow(y, row);
+  }
+
+  /**
+   * Converts a 2D array of luminance data to 1 bit. As above, assume this method is expensive
+   * and do not call it repeatedly. This method is intended for decoding 2D barcodes and may or
+   * may not apply sharpening. Therefore, a row from this matrix may not be identical to one
+   * fetched using getBlackRow(), so don't mix and match between them.
+   *
+   * @return The 2D array of bits for the image (true means black).
+   */
+  public BitMatrix getBlackMatrix() throws NotFoundException {
+    // The matrix is created on demand the first time it is requested, then cached. There are two
+    // reasons for this:
+    // 1. This work will never be done if the caller only installs 1D Reader objects, or if a
+    //    1D Reader finds a barcode before the 2D Readers run.
+    // 2. This work will only be done once even if the caller installs multiple 2D Readers.
+    if (matrix == null) {
+      matrix = binarizer.getBlackMatrix();
+    }
+    return matrix;
+  }
+
+  /**
+   * @return Whether this bitmap can be cropped.
+   */
+  public boolean isCropSupported() {
+    return binarizer.getLuminanceSource().isCropSupported();
+  }
+
+  /**
+   * Returns a new object with cropped image data. Implementations may keep a reference to the
+   * original data rather than a copy. Only callable if isCropSupported() is true.
+   *
+   * @param left The left coordinate, 0 <= left < getWidth().
+   * @param top The top coordinate, 0 <= top <= getHeight().
+   * @param width The width of the rectangle to crop.
+   * @param height The height of the rectangle to crop.
+   * @return A cropped version of this object.
+   */
+  public BinaryBitmap crop(int left, int top, int width, int height) {
+    LuminanceSource newSource = binarizer.getLuminanceSource().crop(left, top, width, height);
+    return new BinaryBitmap(binarizer.createBinarizer(newSource));
+  }
+
+  /**
+   * @return Whether this bitmap supports counter-clockwise rotation.
+   */
+  public boolean isRotateSupported() {
+    return binarizer.getLuminanceSource().isRotateSupported();
+  }
+
+  /**
+   * Returns a new object with rotated image data. Only callable if isRotateSupported() is true.
+   *
+   * @return A rotated version of this object.
+   */
+  public BinaryBitmap rotateCounterClockwise() {
+    LuminanceSource newSource = binarizer.getLuminanceSource().rotateCounterClockwise();
+    return new BinaryBitmap(binarizer.createBinarizer(newSource));
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/ChecksumException.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+/**
+ * Thrown when a barcode was successfully detected and decoded, but
+ * was not returned because its checksum feature failed.
+ *
+ * @author Sean Owen
+ */
+public final class ChecksumException extends ReaderException {
+
+  private static final ChecksumException instance = new ChecksumException();
+
+  private ChecksumException() {
+    // do nothing
+  }
+
+  public static ChecksumException getChecksumInstance() {
+    return instance;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/DecodeHintType.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+/**
+ * Encapsulates a type of hint that a caller may pass to a barcode reader to help it
+ * more quickly or accurately decode it. It is up to implementations to decide what,
+ * if anything, to do with the information that is supplied.
+ *
+ * @author Sean Owen
+ * @author dswitkin@google.com (Daniel Switkin)
+ * @see Reader#decode(BinaryBitmap,java.util.Hashtable)
+ */
+public final class DecodeHintType {
+
+  // No, we can't use an enum here. J2ME doesn't support it.
+
+  /**
+   * Unspecified, application-specific hint. Maps to an unspecified {@link Object}.
+   */
+  public static final DecodeHintType OTHER = new DecodeHintType();
+
+  /**
+   * Image is a pure monochrome image of a barcode. Doesn't matter what it maps to;
+   * use {@link Boolean#TRUE}.
+   */
+  public static final DecodeHintType PURE_BARCODE = new DecodeHintType();
+
+  /**
+   * Image is known to be of one of a few possible formats.
+   * Maps to a {@link java.util.Vector} of {@link BarcodeFormat}s.
+   */
+  public static final DecodeHintType POSSIBLE_FORMATS = new DecodeHintType();
+
+  /**
+   * Spend more time to try to find a barcode; optimize for accuracy, not speed.
+   * Doesn't matter what it maps to; use {@link Boolean#TRUE}.
+   */
+  public static final DecodeHintType TRY_HARDER = new DecodeHintType();
+
+  /**
+   * Specifies what character encoding to use when decoding, where applicable (type String)
+   */
+  public static final DecodeHintType CHARACTER_SET = new DecodeHintType();
+
+  /**
+   * Allowed lengths of encoded data -- reject anything else. Maps to an int[].
+   */
+  public static final DecodeHintType ALLOWED_LENGTHS = new DecodeHintType();
+
+  /**
+   * Assume Code 39 codes employ a check digit. Maps to {@link Boolean}.
+   */
+  public static final DecodeHintType ASSUME_CODE_39_CHECK_DIGIT = new DecodeHintType();
+
+  /**
+   * The caller needs to be notified via callback when a possible {@link ResultPoint}
+   * is found. Maps to a {@link ResultPointCallback}.
+   */
+  public static final DecodeHintType NEED_RESULT_POINT_CALLBACK = new DecodeHintType();
+
+  private DecodeHintType() {
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/EncodeHintType.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+/**
+ * These are a set of hints that you may pass to Writers to specify their behavior.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public final class EncodeHintType {
+
+  /**
+   * Specifies what degree of error correction to use, for example in QR Codes (type Integer).
+   */
+  public static final EncodeHintType ERROR_CORRECTION = new EncodeHintType();
+
+  /**
+   * Specifies what character encoding to use where applicable (type String)
+   */
+  public static final EncodeHintType CHARACTER_SET = new EncodeHintType();
+
+  private EncodeHintType() {
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/FormatException.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+/**
+ * Thrown when a barcode was successfully detected, but some aspect of
+ * the content did not conform to the barcode's format rules. This could have
+ * been due to a mis-detection.
+ *
+ * @author Sean Owen
+ */
+public final class FormatException extends ReaderException {
+
+  private static final FormatException instance = new FormatException();
+
+  private FormatException() {
+    // do nothing
+  }
+
+  public static FormatException getFormatInstance() {
+    return instance;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/LuminanceSource.java

@@ -0,0 +1,113 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+/**
+ * The purpose of this class hierarchy is to abstract different bitmap implementations across
+ * platforms into a standard interface for requesting greyscale luminance values. The interface
+ * only provides immutable methods; therefore crop and rotation create copies. This is to ensure
+ * that one Reader does not modify the original luminance source and leave it in an unknown state
+ * for other Readers in the chain.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public abstract class LuminanceSource {
+
+  private final int width;
+  private final int height;
+
+  protected LuminanceSource(int width, int height) {
+    this.width = width;
+    this.height = height;
+  }
+
+  /**
+   * Fetches one row of luminance data from the underlying platform's bitmap. Values range from
+   * 0 (black) to 255 (white). Because Java does not have an unsigned byte type, callers will have
+   * to bitwise and with 0xff for each value. It is preferable for implementations of this method
+   * to only fetch this row rather than the whole image, since no 2D Readers may be installed and
+   * getMatrix() may never be called.
+   *
+   * @param y The row to fetch, 0 <= y < getHeight().
+   * @param row An optional preallocated array. If null or too small, it will be ignored.
+   *            Always use the returned object, and ignore the .length of the array.
+   * @return An array containing the luminance data.
+   */
+  public abstract byte[] getRow(int y, byte[] row);
+
+  /**
+   * Fetches luminance data for the underlying bitmap. Values should be fetched using:
+   * int luminance = array[y * width + x] & 0xff;
+   *
+   * @return A row-major 2D array of luminance values. Do not use result.length as it may be
+   *         larger than width * height bytes on some platforms. Do not modify the contents
+   *         of the result.
+   */
+  public abstract byte[] getMatrix();
+
+  /**
+   * @return The width of the bitmap.
+   */
+  public final int getWidth() {
+    return width;
+  }
+
+  /**
+   * @return The height of the bitmap.
+   */
+  public final int getHeight() {
+    return height;
+  }
+
+  /**
+   * @return Whether this subclass supports cropping.
+   */
+  public boolean isCropSupported() {
+    return false;
+  }
+
+  /**
+   * Returns a new object with cropped image data. Implementations may keep a reference to the
+   * original data rather than a copy. Only callable if isCropSupported() is true.
+   *
+   * @param left The left coordinate, 0 <= left < getWidth().
+   * @param top The top coordinate, 0 <= top <= getHeight().
+   * @param width The width of the rectangle to crop.
+   * @param height The height of the rectangle to crop.
+   * @return A cropped version of this object.
+   */
+  public LuminanceSource crop(int left, int top, int width, int height) {
+    throw new RuntimeException("This luminance source does not support cropping.");
+  }
+
+  /**
+   * @return Whether this subclass supports counter-clockwise rotation.
+   */
+  public boolean isRotateSupported() {
+    return false;
+  }
+
+  /**
+   * Returns a new object with rotated image data. Only callable if isRotateSupported() is true.
+   *
+   * @return A rotated version of this object.
+   */
+  public LuminanceSource rotateCounterClockwise() {
+    throw new RuntimeException("This luminance source does not support rotation.");
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/NotFoundException.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+/**
+ * Thrown when a barcode was not found in the image. It might have been
+ * partially detected but could not be confirmed.
+ *
+ * @author Sean Owen
+ */
+public final class NotFoundException extends ReaderException {
+
+  private static final NotFoundException instance = new NotFoundException();
+
+  private NotFoundException() {
+    // do nothing
+  }
+
+  public static NotFoundException getNotFoundInstance() {
+    return instance;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/Reader.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+import java.util.Hashtable;
+
+/**
+ * Implementations of this interface can decode an image of a barcode in some format into
+ * the String it encodes. For example, {@link com.google.zxing.qrcode.QRCodeReader} can
+ * decode a QR code. The decoder may optionally receive hints from the caller which may help
+ * it decode more quickly or accurately.
+ *
+ * See {@link com.google.zxing.MultiFormatReader}, which attempts to determine what barcode
+ * format is present within the image as well, and then decodes it accordingly.
+ *
+ * @author Sean Owen
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public interface Reader {
+
+  /**
+   * Locates and decodes a barcode in some format within an image.
+   *
+   * @param image image of barcode to decode
+   * @return String which the barcode encodes
+   * @throws NotFoundException if the barcode cannot be located or decoded for any reason
+   */
+  Result decode(BinaryBitmap image) throws NotFoundException, ChecksumException, FormatException;
+
+  /**
+   * Locates and decodes a barcode in some format within an image. This method also accepts
+   * hints, each possibly associated to some data, which may help the implementation decode.
+   *
+   * @param image image of barcode to decode
+   * @param hints passed as a {@link java.util.Hashtable} from {@link com.google.zxing.DecodeHintType}
+   * to arbitrary data. The
+   * meaning of the data depends upon the hint type. The implementation may or may not do
+   * anything with these hints.
+   * @return String which the barcode encodes
+   * @throws NotFoundException if the barcode cannot be located or decoded for any reason
+   */
+  Result decode(BinaryBitmap image, Hashtable hints) throws NotFoundException, ChecksumException, FormatException;
+
+  /**
+   * Resets any internal state the implementation has after a decode, to prepare it
+   * for reuse.
+   */
+  void reset();
+
+}

OpenPGP-Keychain/src/com/google/zxing/ReaderException.java

@@ -0,0 +1,98 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+/**
+ * The general exception class throw when something goes wrong during decoding of a barcode.
+ * This includes, but is not limited to, failing checksums / error correction algorithms, being
+ * unable to locate finder timing patterns, and so on.
+ *
+ * @author Sean Owen
+ */
+public abstract class ReaderException extends Exception {
+
+  // TODO: Currently we throw up to 400 ReaderExceptions while scanning a single 240x240 image before
+  // rejecting it. This involves a lot of overhead and memory allocation, and affects both performance
+  // and latency on continuous scan clients. In the future, we should change all the decoders not to
+  // throw exceptions for routine events, like not finding a barcode on a given row. Instead, we
+  // should return error codes back to the callers, and simply delete this class. In the mean time, I
+  // have altered this class to be as lightweight as possible, by ignoring the exception string, and
+  // by disabling the generation of stack traces, which is especially time consuming. These are just
+  // temporary measures, pending the big cleanup.
+
+  //private static final ReaderException instance = new ReaderException();
+
+  // EXCEPTION TRACKING SUPPORT
+  // Identifies who is throwing exceptions and how often. To use:
+  //
+  // 1. Uncomment these lines and the code below which uses them.
+  // 2. Uncomment the two corresponding lines in j2se/CommandLineRunner.decode()
+  // 3. Change core to build as Java 1.5 temporarily
+//  private static int exceptionCount = 0;
+//  private static Map<String,Integer> throwers = new HashMap<String,Integer>(32);
+
+  ReaderException() {
+    // do nothing
+  }
+
+  //public static ReaderException getInstance() {
+//    Exception e = new Exception();
+//    // Take the stack frame before this one.
+//    StackTraceElement stack = e.getStackTrace()[1];
+//    String key = stack.getClassName() + "." + stack.getMethodName() + "(), line " +
+//        stack.getLineNumber();
+//    if (throwers.containsKey(key)) {
+//      Integer value = throwers.get(key);
+//      value++;
+//      throwers.put(key, value);
+//    } else {
+//      throwers.put(key, 1);
+//    }
+//    exceptionCount++;
+
+    //return instance;
+  //}
+
+//  public static int getExceptionCountAndReset() {
+//    int temp = exceptionCount;
+//    exceptionCount = 0;
+//    return temp;
+//  }
+//
+//  public static String getThrowersAndReset() {
+//    StringBuilder builder = new StringBuilder(1024);
+//    Object[] keys = throwers.keySet().toArray();
+//    for (int x = 0; x < keys.length; x++) {
+//      String key = (String) keys[x];
+//      Integer value = throwers.get(key);
+//      builder.append(key);
+//      builder.append(": ");
+//      builder.append(value);
+//      builder.append("\n");
+//    }
+//    throwers.clear();
+//    return builder.toString();
+//  }
+
+  // Prevent stack traces from being taken
+  // srowen says: huh, my IDE is saying this is not an override. native methods can't be overridden?
+  // This, at least, does not hurt. Because we use a singleton pattern here, it doesn't matter anyhow.
+  public final Throwable fillInStackTrace() {
+    return null;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/Result.java

@@ -0,0 +1,143 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+import java.util.Enumeration;
+import java.util.Hashtable;
+
+/**
+ * <p>Encapsulates the result of decoding a barcode within an image.</p>
+ *
+ * @author Sean Owen
+ */
+public final class Result {
+
+  private final String text;
+  private final byte[] rawBytes;
+  private ResultPoint[] resultPoints;
+  private final BarcodeFormat format;
+  private Hashtable resultMetadata;
+  private final long timestamp;
+
+  public Result(String text,
+                byte[] rawBytes,
+                ResultPoint[] resultPoints,
+                BarcodeFormat format) {
+    this(text, rawBytes, resultPoints, format, System.currentTimeMillis());
+  }
+
+  public Result(String text,
+                byte[] rawBytes,
+                ResultPoint[] resultPoints,
+                BarcodeFormat format,
+                long timestamp) {
+    if (text == null && rawBytes == null) {
+      throw new IllegalArgumentException("Text and bytes are null");
+    }
+    this.text = text;
+    this.rawBytes = rawBytes;
+    this.resultPoints = resultPoints;
+    this.format = format;
+    this.resultMetadata = null;
+    this.timestamp = timestamp;
+  }
+
+  /**
+   * @return raw text encoded by the barcode, if applicable, otherwise <code>null</code>
+   */
+  public String getText() {
+    return text;
+  }
+
+  /**
+   * @return raw bytes encoded by the barcode, if applicable, otherwise <code>null</code>
+   */
+  public byte[] getRawBytes() {
+    return rawBytes;
+  }
+
+  /**
+   * @return points related to the barcode in the image. These are typically points
+   *         identifying finder patterns or the corners of the barcode. The exact meaning is
+   *         specific to the type of barcode that was decoded.
+   */
+  public ResultPoint[] getResultPoints() {
+    return resultPoints;
+  }
+
+  /**
+   * @return {@link BarcodeFormat} representing the format of the barcode that was decoded
+   */
+  public BarcodeFormat getBarcodeFormat() {
+    return format;
+  }
+
+  /**
+   * @return {@link Hashtable} mapping {@link ResultMetadataType} keys to values. May be
+   *   <code>null</code>. This contains optional metadata about what was detected about the barcode,
+   *   like orientation.
+   */
+  public Hashtable getResultMetadata() {
+    return resultMetadata;
+  }
+
+  public void putMetadata(ResultMetadataType type, Object value) {
+    if (resultMetadata == null) {
+      resultMetadata = new Hashtable(3);
+    }
+    resultMetadata.put(type, value);
+  }
+
+  public void putAllMetadata(Hashtable metadata) {
+    if (metadata != null) {
+      if (resultMetadata == null) {
+        resultMetadata = metadata;
+      } else {
+        Enumeration e = metadata.keys();
+        while (e.hasMoreElements()) {
+          ResultMetadataType key = (ResultMetadataType) e.nextElement();
+          Object value = metadata.get(key);
+          resultMetadata.put(key, value);
+        }
+      }
+    }
+  }
+
+  public void addResultPoints(ResultPoint[] newPoints) {
+    if (resultPoints == null) {
+      resultPoints = newPoints;
+    } else if (newPoints != null && newPoints.length > 0) {
+      ResultPoint[] allPoints = new ResultPoint[resultPoints.length + newPoints.length];
+      System.arraycopy(resultPoints, 0, allPoints, 0, resultPoints.length);
+      System.arraycopy(newPoints, 0, allPoints, resultPoints.length, newPoints.length);
+      resultPoints = allPoints;
+    }
+  }
+
+  public long getTimestamp() {
+    return timestamp;
+  }
+
+  public String toString() {
+    if (text == null) {
+      return "[" + rawBytes.length + " bytes]";
+    } else {
+      return text;
+    }
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/ResultMetadataType.java

@@ -0,0 +1,109 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+import java.util.Hashtable;
+
+/**
+ * Represents some type of metadata about the result of the decoding that the decoder
+ * wishes to communicate back to the caller.
+ *
+ * @author Sean Owen
+ */
+public final class ResultMetadataType {
+
+  // No, we can't use an enum here. J2ME doesn't support it.
+
+  private static final Hashtable VALUES = new Hashtable();
+
+  // No, we can't use an enum here. J2ME doesn't support it.
+
+  /**
+   * Unspecified, application-specific metadata. Maps to an unspecified {@link Object}.
+   */
+  public static final ResultMetadataType OTHER = new ResultMetadataType("OTHER");
+
+  /**
+   * Denotes the likely approximate orientation of the barcode in the image. This value
+   * is given as degrees rotated clockwise from the normal, upright orientation.
+   * For example a 1D barcode which was found by reading top-to-bottom would be
+   * said to have orientation "90". This key maps to an {@link Integer} whose
+   * value is in the range [0,360).
+   */
+  public static final ResultMetadataType ORIENTATION = new ResultMetadataType("ORIENTATION");
+
+  /**
+   * <p>2D barcode formats typically encode text, but allow for a sort of 'byte mode'
+   * which is sometimes used to encode binary data. While {@link Result} makes available
+   * the complete raw bytes in the barcode for these formats, it does not offer the bytes
+   * from the byte segments alone.</p>
+   *
+   * <p>This maps to a {@link java.util.Vector} of byte arrays corresponding to the
+   * raw bytes in the byte segments in the barcode, in order.</p>
+   */
+  public static final ResultMetadataType BYTE_SEGMENTS = new ResultMetadataType("BYTE_SEGMENTS");
+
+  /**
+   * Error correction level used, if applicable. The value type depends on the
+   * format, but is typically a String.
+   */
+  public static final ResultMetadataType ERROR_CORRECTION_LEVEL = new ResultMetadataType("ERROR_CORRECTION_LEVEL");
+
+  /**
+   * For some periodicals, indicates the issue number as an {@link Integer}.
+   */
+  public static final ResultMetadataType ISSUE_NUMBER = new ResultMetadataType("ISSUE_NUMBER");
+
+  /**
+   * For some products, indicates the suggested retail price in the barcode as a
+   * formatted {@link String}.
+   */
+  public static final ResultMetadataType SUGGESTED_PRICE = new ResultMetadataType("SUGGESTED_PRICE");
+
+  /**
+   * For some products, the possible country of manufacture as a {@link String} denoting the
+   * ISO country code. Some map to multiple possible countries, like "US/CA".
+   */
+  public static final ResultMetadataType POSSIBLE_COUNTRY = new ResultMetadataType("POSSIBLE_COUNTRY");
+
+  private final String name;
+
+  private ResultMetadataType(String name) {
+    this.name = name;
+    VALUES.put(name, this);
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public String toString() {
+    return name;
+  }
+
+  public static ResultMetadataType valueOf(String name) {
+    if (name == null || name.length() == 0) {
+      throw new IllegalArgumentException();
+    }
+    ResultMetadataType format = (ResultMetadataType) VALUES.get(name);
+    if (format == null) {
+      throw new IllegalArgumentException();
+    }
+    return format;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/ResultPoint.java

@@ -0,0 +1,129 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+/**
+ * <p>Encapsulates a point of interest in an image containing a barcode. Typically, this
+ * would be the location of a finder pattern or the corner of the barcode, for example.</p>
+ *
+ * @author Sean Owen
+ */
+public class ResultPoint {
+
+  private final float x;
+  private final float y;
+
+  public ResultPoint(float x, float y) {
+    this.x = x;
+    this.y = y;
+  }
+
+  public final float getX() {
+    return x;
+  }
+
+  public final float getY() {
+    return y;
+  }
+
+  public boolean equals(Object other) {
+    if (other instanceof ResultPoint) {
+      ResultPoint otherPoint = (ResultPoint) other;
+      return x == otherPoint.x && y == otherPoint.y;
+    }
+    return false;
+  }
+
+  public int hashCode() {
+    return 31 * Float.floatToIntBits(x) + Float.floatToIntBits(y);
+  }
+
+  public String toString() {
+    StringBuffer result = new StringBuffer(25);
+    result.append('(');
+    result.append(x);
+    result.append(',');
+    result.append(y);
+    result.append(')');
+    return result.toString();
+  }
+
+  /**
+   * <p>Orders an array of three ResultPoints in an order [A,B,C] such that AB < AC and
+   * BC < AC and the angle between BC and BA is less than 180 degrees.
+   */
+  public static void orderBestPatterns(ResultPoint[] patterns) {
+
+    // Find distances between pattern centers
+    float zeroOneDistance = distance(patterns[0], patterns[1]);
+    float oneTwoDistance = distance(patterns[1], patterns[2]);
+    float zeroTwoDistance = distance(patterns[0], patterns[2]);
+
+    ResultPoint pointA;
+    ResultPoint pointB;
+    ResultPoint pointC;
+    // Assume one closest to other two is B; A and C will just be guesses at first
+    if (oneTwoDistance >= zeroOneDistance && oneTwoDistance >= zeroTwoDistance) {
+      pointB = patterns[0];
+      pointA = patterns[1];
+      pointC = patterns[2];
+    } else if (zeroTwoDistance >= oneTwoDistance && zeroTwoDistance >= zeroOneDistance) {
+      pointB = patterns[1];
+      pointA = patterns[0];
+      pointC = patterns[2];
+    } else {
+      pointB = patterns[2];
+      pointA = patterns[0];
+      pointC = patterns[1];
+    }
+
+    // Use cross product to figure out whether A and C are correct or flipped.
+    // This asks whether BC x BA has a positive z component, which is the arrangement
+    // we want for A, B, C. If it's negative, then we've got it flipped around and
+    // should swap A and C.
+    if (crossProductZ(pointA, pointB, pointC) < 0.0f) {
+      ResultPoint temp = pointA;
+      pointA = pointC;
+      pointC = temp;
+    }
+
+    patterns[0] = pointA;
+    patterns[1] = pointB;
+    patterns[2] = pointC;
+  }
+
+
+  /**
+   * @return distance between two points
+   */
+  public static float distance(ResultPoint pattern1, ResultPoint pattern2) {
+    float xDiff = pattern1.getX() - pattern2.getX();
+    float yDiff = pattern1.getY() - pattern2.getY();
+    return (float) Math.sqrt((double) (xDiff * xDiff + yDiff * yDiff));
+  }
+
+  /**
+   * Returns the z component of the cross product between vectors BC and BA.
+   */
+  private static float crossProductZ(ResultPoint pointA, ResultPoint pointB, ResultPoint pointC) {
+    float bX = pointB.x;
+    float bY = pointB.y;
+    return ((pointC.x - bX) * (pointA.y - bY)) - ((pointC.y - bY) * (pointA.x - bX));
+  }
+
+
+}

OpenPGP-Keychain/src/com/google/zxing/ResultPointCallback.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+/**
+ * Callback which is invoked when a possible result point (significant
+ * point in the barcode image such as a corner) is found.
+ *
+ * @see DecodeHintType#NEED_RESULT_POINT_CALLBACK
+ */
+public interface ResultPointCallback {
+
+  void foundPossibleResultPoint(ResultPoint point);
+
+}

OpenPGP-Keychain/src/com/google/zxing/Writer.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+import com.google.zxing.common.BitMatrix;
+
+import java.util.Hashtable;
+
+/**
+ * The base class for all objects which encode/generate a barcode image.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public interface Writer {
+
+  /**
+   * Encode a barcode using the default settings.
+   *
+   * @param contents The contents to encode in the barcode
+   * @param format The barcode format to generate
+   * @param width The preferred width in pixels
+   * @param height The preferred height in pixels
+   * @return The generated barcode as a Matrix of unsigned bytes (0 == black, 255 == white)
+   */
+  BitMatrix encode(String contents, BarcodeFormat format, int width, int height)
+      throws WriterException;
+
+  /**
+   *
+   * @param contents The contents to encode in the barcode
+   * @param format The barcode format to generate
+   * @param width The preferred width in pixels
+   * @param height The preferred height in pixels
+   * @param hints Additional parameters to supply to the encoder
+   * @return The generated barcode as a Matrix of unsigned bytes (0 == black, 255 == white)
+   */
+  BitMatrix encode(String contents, BarcodeFormat format, int width, int height, Hashtable hints)
+      throws WriterException;
+
+}

OpenPGP-Keychain/src/com/google/zxing/WriterException.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing;
+
+/**
+ * A base class which covers the range of exceptions which may occur when encoding a barcode using
+ * the Writer framework.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public final class WriterException extends Exception {
+
+  public WriterException() {
+    super();
+  }
+
+  public WriterException(String message) {
+    super(message);
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/BitArray.java

@@ -0,0 +1,246 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+/**
+ * <p>A simple, fast array of bits, represented compactly by an array of ints internally.</p>
+ *
+ * @author Sean Owen
+ */
+public final class BitArray {
+  // I have changed these members to be public so ProGuard can inline get() and set(). Ideally
+  // they'd be private and we'd use the -allowaccessmodification flag, but Dalvik rejects the
+  // resulting binary at runtime on Android. If we find a solution to this, these should be changed
+  // back to private.
+  public int[] bits;
+  public int size;
+
+  public BitArray() {
+    this.size = 0;
+    this.bits = new int[1];
+  }
+
+  public BitArray(int size) {
+    this.size = size;
+    this.bits = makeArray(size);
+  }
+
+  public int getSize() {
+    return size;
+  }
+
+  public int getSizeInBytes() {
+    return (size + 7) >> 3;
+  }
+
+  private void ensureCapacity(int size) {
+    if (size > bits.length << 5) {
+      int[] newBits = makeArray(size);
+      System.arraycopy(bits, 0, newBits, 0, bits.length);
+      this.bits = newBits;
+    }
+  }
+
+  /**
+   * @param i bit to get
+   * @return true iff bit i is set
+   */
+  public boolean get(int i) {
+    return (bits[i >> 5] & (1 << (i & 0x1F))) != 0;
+  }
+
+  /**
+   * Sets bit i.
+   *
+   * @param i bit to set
+   */
+  public void set(int i) {
+    bits[i >> 5] |= 1 << (i & 0x1F);
+  }
+
+  /**
+   * Flips bit i.
+   *
+   * @param i bit to set
+   */
+  public void flip(int i) {
+    bits[i >> 5] ^= 1 << (i & 0x1F);
+  }
+
+  /**
+   * Sets a block of 32 bits, starting at bit i.
+   *
+   * @param i first bit to set
+   * @param newBits the new value of the next 32 bits. Note again that the least-significant bit
+   * corresponds to bit i, the next-least-significant to i+1, and so on.
+   */
+  public void setBulk(int i, int newBits) {
+    bits[i >> 5] = newBits;
+  }
+
+  /**
+   * Clears all bits (sets to false).
+   */
+  public void clear() {
+    int max = bits.length;
+    for (int i = 0; i < max; i++) {
+      bits[i] = 0;
+    }
+  }
+
+  /**
+   * Efficient method to check if a range of bits is set, or not set.
+   *
+   * @param start start of range, inclusive.
+   * @param end end of range, exclusive
+   * @param value if true, checks that bits in range are set, otherwise checks that they are not set
+   * @return true iff all bits are set or not set in range, according to value argument
+   * @throws IllegalArgumentException if end is less than or equal to start
+   */
+  public boolean isRange(int start, int end, boolean value) {
+    if (end < start) {
+      throw new IllegalArgumentException();
+    }
+    if (end == start) {
+      return true; // empty range matches
+    }
+    end--; // will be easier to treat this as the last actually set bit -- inclusive
+    int firstInt = start >> 5;
+    int lastInt = end >> 5;
+    for (int i = firstInt; i <= lastInt; i++) {
+      int firstBit = i > firstInt ? 0 : start & 0x1F;
+      int lastBit = i < lastInt ? 31 : end & 0x1F;
+      int mask;
+      if (firstBit == 0 && lastBit == 31) {
+        mask = -1;
+      } else {
+        mask = 0;
+        for (int j = firstBit; j <= lastBit; j++) {
+          mask |= 1 << j;
+        }
+      }
+
+      // Return false if we're looking for 1s and the masked bits[i] isn't all 1s (that is,
+      // equals the mask, or we're looking for 0s and the masked portion is not all 0s
+      if ((bits[i] & mask) != (value ? mask : 0)) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  public void appendBit(boolean bit) {
+    ensureCapacity(size + 1);
+    if (bit) {
+      bits[size >> 5] |= (1 << (size & 0x1F));
+    }
+    size++;
+  }
+
+  /**
+   * Appends the least-significant bits, from value, in order from most-significant to
+   * least-significant. For example, appending 6 bits from 0x000001E will append the bits
+   * 0, 1, 1, 1, 1, 0 in that order.
+   */
+  public void appendBits(int value, int numBits) {
+    if (numBits < 0 || numBits > 32) {
+      throw new IllegalArgumentException("Num bits must be between 0 and 32");
+    }
+    ensureCapacity(size + numBits);
+    for (int numBitsLeft = numBits; numBitsLeft > 0; numBitsLeft--) {
+      appendBit(((value >> (numBitsLeft - 1)) & 0x01) == 1);
+    }
+  }
+
+  public void appendBitArray(BitArray other) {
+    int otherSize = other.getSize();
+    ensureCapacity(size + otherSize);
+    for (int i = 0; i < otherSize; i++) {
+      appendBit(other.get(i));
+    }
+  }
+
+  public void xor(BitArray other) {
+    if (bits.length != other.bits.length) {
+      throw new IllegalArgumentException("Sizes don't match");
+    }
+    for (int i = 0; i < bits.length; i++) {
+      // The last byte could be incomplete (i.e. not have 8 bits in
+      // it) but there is no problem since 0 XOR 0 == 0.
+      bits[i] ^= other.bits[i];
+    }
+  }
+
+  /**
+   *
+   * @param bitOffset first bit to start writing
+   * @param array array to write into. Bytes are written most-significant byte first. This is the opposite
+   *  of the internal representation, which is exposed by {@link #getBitArray()}
+   * @param offset position in array to start writing
+   * @param numBytes how many bytes to write
+   */
+  public void toBytes(int bitOffset, byte[] array, int offset, int numBytes) {
+    for (int i = 0; i < numBytes; i++) {
+      int theByte = 0;
+      for (int j = 0; j < 8; j++) {
+        if (get(bitOffset)) {
+          theByte |= 1 << (7 - j);
+        }
+        bitOffset++;
+      }
+      array[offset + i] = (byte) theByte;
+    }
+  }
+
+  /**
+   * @return underlying array of ints. The first element holds the first 32 bits, and the least
+   *         significant bit is bit 0.
+   */
+  public int[] getBitArray() {
+    return bits;
+  }
+
+  /**
+   * Reverses all bits in the array.
+   */
+  public void reverse() {
+    int[] newBits = new int[bits.length];
+    int size = this.size;
+    for (int i = 0; i < size; i++) {
+      if (get(size - i - 1)) {
+        newBits[i >> 5] |= 1 << (i & 0x1F);
+      }
+    }
+    bits = newBits;
+  }
+
+  private static int[] makeArray(int size) {
+    return new int[(size + 31) >> 5];
+  }
+
+  public String toString() {
+    StringBuffer result = new StringBuffer(size);
+    for (int i = 0; i < size; i++) {
+      if ((i & 0x07) == 0) {
+        result.append(' ');
+      }
+      result.append(get(i) ? 'X' : '.');
+    }
+    return result.toString();
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/BitMatrix.java

@@ -0,0 +1,247 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+/**
+ * <p>Represents a 2D matrix of bits. In function arguments below, and throughout the common
+ * module, x is the column position, and y is the row position. The ordering is always x, y.
+ * The origin is at the top-left.</p>
+ *
+ * <p>Internally the bits are represented in a 1-D array of 32-bit ints. However, each row begins
+ * with a new int. This is done intentionally so that we can copy out a row into a BitArray very
+ * efficiently.</p>
+ *
+ * <p>The ordering of bits is row-major. Within each int, the least significant bits are used first,
+ * meaning they represent lower x values. This is compatible with BitArray's implementation.</p>
+ *
+ * @author Sean Owen
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public final class BitMatrix {
+  // Just like BitArray, these need to be public so ProGuard can inline them.
+  public final int width;
+  public final int height;
+  public final int rowSize;
+  public final int[] bits;
+
+  // A helper to construct a square matrix.
+  public BitMatrix(int dimension) {
+    this(dimension, dimension);
+  }
+
+  public BitMatrix(int width, int height) {
+    if (width < 1 || height < 1) {
+      throw new IllegalArgumentException("Both dimensions must be greater than 0");
+    }
+    this.width = width;
+    this.height = height;
+    this.rowSize = (width + 31) >> 5;
+    bits = new int[rowSize * height];
+  }
+
+  /**
+   * <p>Gets the requested bit, where true means black.</p>
+   *
+   * @param x The horizontal component (i.e. which column)
+   * @param y The vertical component (i.e. which row)
+   * @return value of given bit in matrix
+   */
+  public boolean get(int x, int y) {
+    int offset = y * rowSize + (x >> 5);
+    return ((bits[offset] >>> (x & 0x1f)) & 1) != 0;
+  }
+
+  /**
+   * <p>Sets the given bit to true.</p>
+   *
+   * @param x The horizontal component (i.e. which column)
+   * @param y The vertical component (i.e. which row)
+   */
+  public void set(int x, int y) {
+    int offset = y * rowSize + (x >> 5);
+    bits[offset] |= 1 << (x & 0x1f);
+  }
+
+  /**
+   * <p>Flips the given bit.</p>
+   *
+   * @param x The horizontal component (i.e. which column)
+   * @param y The vertical component (i.e. which row)
+   */
+  public void flip(int x, int y) {
+    int offset = y * rowSize + (x >> 5);
+    bits[offset] ^= 1 << (x & 0x1f);
+  }
+
+  /**
+   * Clears all bits (sets to false).
+   */
+  public void clear() {
+    int max = bits.length;
+    for (int i = 0; i < max; i++) {
+      bits[i] = 0;
+    }
+  }
+
+  /**
+   * <p>Sets a square region of the bit matrix to true.</p>
+   *
+   * @param left The horizontal position to begin at (inclusive)
+   * @param top The vertical position to begin at (inclusive)
+   * @param width The width of the region
+   * @param height The height of the region
+   */
+  public void setRegion(int left, int top, int width, int height) {
+    if (top < 0 || left < 0) {
+      throw new IllegalArgumentException("Left and top must be nonnegative");
+    }
+    if (height < 1 || width < 1) {
+      throw new IllegalArgumentException("Height and width must be at least 1");
+    }
+    int right = left + width;
+    int bottom = top + height;
+    if (bottom > this.height || right > this.width) {
+      throw new IllegalArgumentException("The region must fit inside the matrix");
+    }
+    for (int y = top; y < bottom; y++) {
+      int offset = y * rowSize;
+      for (int x = left; x < right; x++) {
+        bits[offset + (x >> 5)] |= 1 << (x & 0x1f);
+      }
+    }
+  }
+
+  /**
+   * A fast method to retrieve one row of data from the matrix as a BitArray.
+   *
+   * @param y The row to retrieve
+   * @param row An optional caller-allocated BitArray, will be allocated if null or too small
+   * @return The resulting BitArray - this reference should always be used even when passing
+   *         your own row
+   */
+  public BitArray getRow(int y, BitArray row) {
+    if (row == null || row.getSize() < width) {
+      row = new BitArray(width);
+    }
+    int offset = y * rowSize;
+    for (int x = 0; x < rowSize; x++) {
+      row.setBulk(x << 5, bits[offset + x]);
+    }
+    return row;
+  }
+
+  /**
+   * This is useful in detecting a corner of a 'pure' barcode.
+   *
+   * @return {x,y} coordinate of top-left-most 1 bit, or null if it is all white
+   */
+  public int[] getTopLeftOnBit() {
+    int bitsOffset = 0;
+    while (bitsOffset < bits.length && bits[bitsOffset] == 0) {
+      bitsOffset++;
+    }
+    if (bitsOffset == bits.length) {
+      return null;
+    }
+    int y = bitsOffset / rowSize;
+    int x = (bitsOffset % rowSize) << 5;
+
+    int theBits = bits[bitsOffset];
+    int bit = 0;
+    while ((theBits << (31-bit)) == 0) {
+      bit++;
+    }
+    x += bit;
+    return new int[] {x, y};
+  }
+
+  public int[] getBottomRightOnBit() {
+    int bitsOffset = bits.length - 1;
+    while (bitsOffset >= 0 && bits[bitsOffset] == 0) {
+      bitsOffset--;
+    }
+    if (bitsOffset < 0) {
+      return null;
+    }
+
+    int y = bitsOffset / rowSize;
+    int x = (bitsOffset % rowSize) << 5;
+
+    int theBits = bits[bitsOffset];
+    int bit = 31;
+    while ((theBits >>> bit) == 0) {
+      bit--;
+    }
+    x += bit;
+
+    return new int[] {x, y};
+  }
+
+  /**
+   * @return The width of the matrix
+   */
+  public int getWidth() {
+    return width;
+  }
+
+  /**
+   * @return The height of the matrix
+   */
+  public int getHeight() {
+    return height;
+  }
+
+  public boolean equals(Object o) {
+    if (!(o instanceof BitMatrix)) {
+      return false;
+    }
+    BitMatrix other = (BitMatrix) o;
+    if (width != other.width || height != other.height ||
+        rowSize != other.rowSize || bits.length != other.bits.length) {
+      return false;
+    }
+    for (int i = 0; i < bits.length; i++) {
+      if (bits[i] != other.bits[i]) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  public int hashCode() {
+    int hash = width;
+    hash = 31 * hash + width;
+    hash = 31 * hash + height;
+    hash = 31 * hash + rowSize;
+    for (int i = 0; i < bits.length; i++) {
+      hash = 31 * hash + bits[i];
+    }
+    return hash;
+  }
+
+  public String toString() {
+    StringBuffer result = new StringBuffer(height * (width + 1));
+    for (int y = 0; y < height; y++) {
+      for (int x = 0; x < width; x++) {
+        result.append(get(x, y) ? "X " : "  ");
+      }
+      result.append('\n');
+    }
+    return result.toString();
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/BitSource.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+/**
+ * <p>This provides an easy abstraction to read bits at a time from a sequence of bytes, where the
+ * number of bits read is not often a multiple of 8.</p>
+ *
+ * <p>This class is thread-safe but not reentrant. Unless the caller modifies the bytes array
+ * it passed in, in which case all bets are off.</p>
+ *
+ * @author Sean Owen
+ */
+public final class BitSource {
+
+  private final byte[] bytes;
+  private int byteOffset;
+  private int bitOffset;
+
+  /**
+   * @param bytes bytes from which this will read bits. Bits will be read from the first byte first.
+   * Bits are read within a byte from most-significant to least-significant bit.
+   */
+  public BitSource(byte[] bytes) {
+    this.bytes = bytes;
+  }
+
+  /**
+   * @param numBits number of bits to read
+   * @return int representing the bits read. The bits will appear as the least-significant
+   *         bits of the int
+   * @throws IllegalArgumentException if numBits isn't in [1,32]
+   */
+  public int readBits(int numBits) {
+    if (numBits < 1 || numBits > 32) {
+      throw new IllegalArgumentException();
+    }
+
+    int result = 0;
+
+    // First, read remainder from current byte
+    if (bitOffset > 0) {
+      int bitsLeft = 8 - bitOffset;
+      int toRead = numBits < bitsLeft ? numBits : bitsLeft;
+      int bitsToNotRead = bitsLeft - toRead;
+      int mask = (0xFF >> (8 - toRead)) << bitsToNotRead;
+      result = (bytes[byteOffset] & mask) >> bitsToNotRead;
+      numBits -= toRead;
+      bitOffset += toRead;
+      if (bitOffset == 8) {
+        bitOffset = 0;
+        byteOffset++;
+      }
+    }
+
+    // Next read whole bytes
+    if (numBits > 0) {
+      while (numBits >= 8) {
+        result = (result << 8) | (bytes[byteOffset] & 0xFF);
+        byteOffset++;
+        numBits -= 8;
+      }
+
+      // Finally read a partial byte
+      if (numBits > 0) {
+        int bitsToNotRead = 8 - numBits;
+        int mask = (0xFF >> bitsToNotRead) << bitsToNotRead;
+        result = (result << numBits) | ((bytes[byteOffset] & mask) >> bitsToNotRead);
+        bitOffset += numBits;
+      }
+    }
+
+    return result;
+  }
+
+  /**
+   * @return number of bits that can be read successfully
+   */
+  public int available() {
+    return 8 * (bytes.length - byteOffset) - bitOffset;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/CharacterSetECI.java

@@ -0,0 +1,110 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import java.util.Hashtable;
+
+/**
+ * Encapsulates a Character Set ECI, according to "Extended Channel Interpretations" 5.3.1.1
+ * of ISO 18004.
+ *
+ * @author Sean Owen
+ */
+public final class CharacterSetECI extends ECI {
+
+  private static Hashtable VALUE_TO_ECI;
+  private static Hashtable NAME_TO_ECI;
+
+  private static void initialize() {
+    VALUE_TO_ECI = new Hashtable(29);
+    NAME_TO_ECI = new Hashtable(29);
+    // TODO figure out if these values are even right!
+    addCharacterSet(0, "Cp437");
+    addCharacterSet(1, new String[] {"ISO8859_1", "ISO-8859-1"});
+    addCharacterSet(2, "Cp437");
+    addCharacterSet(3, new String[] {"ISO8859_1", "ISO-8859-1"});
+    addCharacterSet(4, "ISO8859_2");
+    addCharacterSet(5, "ISO8859_3");
+    addCharacterSet(6, "ISO8859_4");
+    addCharacterSet(7, "ISO8859_5");
+    addCharacterSet(8, "ISO8859_6");
+    addCharacterSet(9, "ISO8859_7");
+    addCharacterSet(10, "ISO8859_8");
+    addCharacterSet(11, "ISO8859_9");
+    addCharacterSet(12, "ISO8859_10");
+    addCharacterSet(13, "ISO8859_11");
+    addCharacterSet(15, "ISO8859_13");
+    addCharacterSet(16, "ISO8859_14");
+    addCharacterSet(17, "ISO8859_15");
+    addCharacterSet(18, "ISO8859_16");
+    addCharacterSet(20, new String[] {"SJIS", "Shift_JIS"});
+  }
+
+  private final String encodingName;
+
+  private CharacterSetECI(int value, String encodingName) {
+    super(value);
+    this.encodingName = encodingName;
+  }
+
+  public String getEncodingName() {
+    return encodingName;
+  }
+
+  private static void addCharacterSet(int value, String encodingName) {
+    CharacterSetECI eci = new CharacterSetECI(value, encodingName);
+    VALUE_TO_ECI.put(new Integer(value), eci); // can't use valueOf
+    NAME_TO_ECI.put(encodingName, eci);
+  }
+
+  private static void addCharacterSet(int value, String[] encodingNames) {
+    CharacterSetECI eci = new CharacterSetECI(value, encodingNames[0]);
+    VALUE_TO_ECI.put(new Integer(value), eci); // can't use valueOf
+    for (int i = 0; i < encodingNames.length; i++) {
+      NAME_TO_ECI.put(encodingNames[i], eci);
+    }
+  }
+
+  /**
+   * @param value character set ECI value
+   * @return CharacterSetECI representing ECI of given value, or null if it is legal but
+   *   unsupported
+   * @throws IllegalArgumentException if ECI value is invalid
+   */
+  public static CharacterSetECI getCharacterSetECIByValue(int value) {
+    if (VALUE_TO_ECI == null) {
+      initialize();
+    }
+    if (value < 0 || value >= 900) {
+      throw new IllegalArgumentException("Bad ECI value: " + value);
+    }
+    return (CharacterSetECI) VALUE_TO_ECI.get(new Integer(value));
+  }
+
+  /**
+   * @param name character set ECI encoding name
+   * @return CharacterSetECI representing ECI for character encoding, or null if it is legal
+   *   but unsupported
+   */
+  public static CharacterSetECI getCharacterSetECIByName(String name) {
+    if (NAME_TO_ECI == null) {
+      initialize();
+    }
+    return (CharacterSetECI) NAME_TO_ECI.get(name);
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/Collections.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import java.util.Vector;
+
+/**
+ * <p>This is basically a substitute for <code>java.util.Collections</code>, which is not
+ * present in MIDP 2.0 / CLDC 1.1.</p>
+ *
+ * @author Sean Owen
+ */
+public final class Collections {
+
+  private Collections() {
+  }
+
+  /**
+   * Sorts its argument (destructively) using insert sort; in the context of this package
+   * insertion sort is simple and efficient given its relatively small inputs.
+   *
+   * @param vector vector to sort
+   * @param comparator comparator to define sort ordering
+   */
+  public static void insertionSort(Vector vector, Comparator comparator) {
+    int max = vector.size();
+    for (int i = 1; i < max; i++) {
+      Object value = vector.elementAt(i);
+      int j = i - 1;
+      Object valueB;
+      while (j >= 0 && comparator.compare((valueB = vector.elementAt(j)), value) > 0) {
+        vector.setElementAt(valueB, j + 1);
+        j--;
+      }
+      vector.setElementAt(value, j + 1);
+    }
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/Comparator.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+/**
+ * This is merely a clone of <code>Comparator</code> since it is not available in
+ * CLDC 1.1 / MIDP 2.0.
+ */
+public interface Comparator {
+
+  int compare(Object o1, Object o2);
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/DecoderResult.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import java.util.Vector;
+
+/**
+ * <p>Encapsulates the result of decoding a matrix of bits. This typically
+ * applies to 2D barcode formats. For now it contains the raw bytes obtained,
+ * as well as a String interpretation of those bytes, if applicable.</p>
+ *
+ * @author Sean Owen
+ */
+public final class DecoderResult {
+
+  private final byte[] rawBytes;
+  private final String text;
+  private final Vector byteSegments;
+  private final String ecLevel;
+
+  public DecoderResult(byte[] rawBytes, String text, Vector byteSegments, String ecLevel) {
+    if (rawBytes == null && text == null) {
+      throw new IllegalArgumentException();
+    }
+    this.rawBytes = rawBytes;
+    this.text = text;
+    this.byteSegments = byteSegments;
+    this.ecLevel = ecLevel;
+  }
+
+  public byte[] getRawBytes() {
+    return rawBytes;
+  }
+
+  public String getText() {
+    return text;
+  }
+
+  public Vector getByteSegments() {
+    return byteSegments;
+  }
+
+  public String getECLevel() {
+    return ecLevel;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/DefaultGridSampler.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import com.google.zxing.NotFoundException;
+
+/**
+ * @author Sean Owen
+ */
+public final class DefaultGridSampler extends GridSampler {
+
+  public BitMatrix sampleGrid(BitMatrix image,
+                              int dimensionX,
+                              int dimensionY,
+                              float p1ToX, float p1ToY,
+                              float p2ToX, float p2ToY,
+                              float p3ToX, float p3ToY,
+                              float p4ToX, float p4ToY,
+                              float p1FromX, float p1FromY,
+                              float p2FromX, float p2FromY,
+                              float p3FromX, float p3FromY,
+                              float p4FromX, float p4FromY) throws NotFoundException {
+
+    PerspectiveTransform transform = PerspectiveTransform.quadrilateralToQuadrilateral(
+        p1ToX, p1ToY, p2ToX, p2ToY, p3ToX, p3ToY, p4ToX, p4ToY,
+        p1FromX, p1FromY, p2FromX, p2FromY, p3FromX, p3FromY, p4FromX, p4FromY);
+
+    return sampleGrid(image, dimensionX, dimensionY, transform);
+  }
+
+  public BitMatrix sampleGrid(BitMatrix image,
+                              int dimensionX,
+                              int dimensionY,
+                              PerspectiveTransform transform) throws NotFoundException {
+    if (dimensionX <= 0 || dimensionY <= 0) {
+      throw NotFoundException.getNotFoundInstance();      
+    }
+    BitMatrix bits = new BitMatrix(dimensionX, dimensionY);
+    float[] points = new float[dimensionX << 1];
+    for (int y = 0; y < dimensionY; y++) {
+      int max = points.length;
+      float iValue = (float) y + 0.5f;
+      for (int x = 0; x < max; x += 2) {
+        points[x] = (float) (x >> 1) + 0.5f;
+        points[x + 1] = iValue;
+      }
+      transform.transformPoints(points);
+      // Quick check to see if points transformed to something inside the image;
+      // sufficient to check the endpoints
+      checkAndNudgePoints(image, points);
+      try {
+        for (int x = 0; x < max; x += 2) {
+          if (image.get((int) points[x], (int) points[x + 1])) {
+            // Black(-ish) pixel
+            bits.set(x >> 1, y);
+          }
+        }
+      } catch (ArrayIndexOutOfBoundsException aioobe) {
+        // This feels wrong, but, sometimes if the finder patterns are misidentified, the resulting
+        // transform gets "twisted" such that it maps a straight line of points to a set of points
+        // whose endpoints are in bounds, but others are not. There is probably some mathematical
+        // way to detect this about the transformation that I don't know yet.
+        // This results in an ugly runtime exception despite our clever checks above -- can't have
+        // that. We could check each point's coordinates but that feels duplicative. We settle for
+        // catching and wrapping ArrayIndexOutOfBoundsException.
+        throw NotFoundException.getNotFoundInstance();
+      }
+    }
+    return bits;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/DetectorResult.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import com.google.zxing.ResultPoint;
+
+/**
+ * <p>Encapsulates the result of detecting a barcode in an image. This includes the raw
+ * matrix of black/white pixels corresponding to the barcode, and possibly points of interest
+ * in the image, like the location of finder patterns or corners of the barcode in the image.</p>
+ *
+ * @author Sean Owen
+ */
+public class DetectorResult {
+
+  private final BitMatrix bits;
+  private final ResultPoint[] points;
+
+  public DetectorResult(BitMatrix bits, ResultPoint[] points) {
+    this.bits = bits;
+    this.points = points;
+  }
+
+  public BitMatrix getBits() {
+    return bits;
+  }
+
+  public ResultPoint[] getPoints() {
+    return points;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/ECI.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+/**
+ * Superclass of classes encapsulating types ECIs, according to "Extended Channel Interpretations"
+ * 5.3 of ISO 18004.
+ *
+ * @author Sean Owen
+ */
+public abstract class ECI {
+
+  private final int value;
+
+  ECI(int value) {
+    this.value = value;
+  }
+
+  public int getValue() {
+    return value;
+  }
+
+  /**
+   * @param value ECI value
+   * @return ECI representing ECI of given value, or null if it is legal but unsupported
+   * @throws IllegalArgumentException if ECI value is invalid
+   */
+  public static ECI getECIByValue(int value) {
+    if (value < 0 || value > 999999) {
+      throw new IllegalArgumentException("Bad ECI value: " + value);
+    }
+    if (value < 900) { // Character set ECIs use 000000 - 000899
+      return CharacterSetECI.getCharacterSetECIByValue(value);
+    }
+    return null;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/GlobalHistogramBinarizer.java

@@ -0,0 +1,194 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import com.google.zxing.Binarizer;
+import com.google.zxing.LuminanceSource;
+import com.google.zxing.NotFoundException;
+
+/**
+ * This Binarizer implementation uses the old ZXing global histogram approach. It is suitable
+ * for low-end mobile devices which don't have enough CPU or memory to use a local thresholding
+ * algorithm. However, because it picks a global black point, it cannot handle difficult shadows
+ * and gradients.
+ *
+ * Faster mobile devices and all desktop applications should probably use HybridBinarizer instead.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ * @author Sean Owen
+ */
+public class GlobalHistogramBinarizer extends Binarizer {
+
+  private static final int LUMINANCE_BITS = 5;
+  private static final int LUMINANCE_SHIFT = 8 - LUMINANCE_BITS;
+  private static final int LUMINANCE_BUCKETS = 1 << LUMINANCE_BITS;
+
+  private byte[] luminances = null;
+  private int[] buckets = null;
+
+  public GlobalHistogramBinarizer(LuminanceSource source) {
+    super(source);
+  }
+
+  // Applies simple sharpening to the row data to improve performance of the 1D Readers.
+  public BitArray getBlackRow(int y, BitArray row) throws NotFoundException {
+    LuminanceSource source = getLuminanceSource();
+    int width = source.getWidth();
+    if (row == null || row.getSize() < width) {
+      row = new BitArray(width);
+    } else {
+      row.clear();
+    }
+
+    initArrays(width);
+    byte[] localLuminances = source.getRow(y, luminances);
+    int[] localBuckets = buckets;
+    for (int x = 0; x < width; x++) {
+      int pixel = localLuminances[x] & 0xff;
+      localBuckets[pixel >> LUMINANCE_SHIFT]++;
+    }
+    int blackPoint = estimateBlackPoint(localBuckets);
+
+    int left = localLuminances[0] & 0xff;
+    int center = localLuminances[1] & 0xff;
+    for (int x = 1; x < width - 1; x++) {
+      int right = localLuminances[x + 1] & 0xff;
+      // A simple -1 4 -1 box filter with a weight of 2.
+      int luminance = ((center << 2) - left - right) >> 1;
+      if (luminance < blackPoint) {
+        row.set(x);
+      }
+      left = center;
+      center = right;
+    }
+    return row;
+  }
+
+  // Does not sharpen the data, as this call is intended to only be used by 2D Readers.
+  public BitMatrix getBlackMatrix() throws NotFoundException {
+    LuminanceSource source = getLuminanceSource();
+    int width = source.getWidth();
+    int height = source.getHeight();
+    BitMatrix matrix = new BitMatrix(width, height);
+
+    // Quickly calculates the histogram by sampling four rows from the image. This proved to be
+    // more robust on the blackbox tests than sampling a diagonal as we used to do.
+    initArrays(width);
+    int[] localBuckets = buckets;
+    for (int y = 1; y < 5; y++) {
+      int row = height * y / 5;
+      byte[] localLuminances = source.getRow(row, luminances);
+      int right = (width << 2) / 5;
+      for (int x = width / 5; x < right; x++) {
+        int pixel = localLuminances[x] & 0xff;
+        localBuckets[pixel >> LUMINANCE_SHIFT]++;
+      }
+    }
+    int blackPoint = estimateBlackPoint(localBuckets);
+
+    // We delay reading the entire image luminance until the black point estimation succeeds.
+    // Although we end up reading four rows twice, it is consistent with our motto of
+    // "fail quickly" which is necessary for continuous scanning.
+    byte[] localLuminances = source.getMatrix();
+    for (int y = 0; y < height; y++) {
+      int offset = y * width;
+      for (int x = 0; x< width; x++) {
+        int pixel = localLuminances[offset + x] & 0xff;
+        if (pixel < blackPoint) {
+          matrix.set(x, y);
+        }
+      }
+    }
+
+    return matrix;
+  }
+
+  public Binarizer createBinarizer(LuminanceSource source) {
+    return new GlobalHistogramBinarizer(source);
+  }
+
+  private void initArrays(int luminanceSize) {
+    if (luminances == null || luminances.length < luminanceSize) {
+      luminances = new byte[luminanceSize];
+    }
+    if (buckets == null) {
+      buckets = new int[LUMINANCE_BUCKETS];
+    } else {
+      for (int x = 0; x < LUMINANCE_BUCKETS; x++) {
+        buckets[x] = 0;
+      }
+    }
+  }
+
+  private static int estimateBlackPoint(int[] buckets) throws NotFoundException {
+    // Find the tallest peak in the histogram.
+    int numBuckets = buckets.length;
+    int maxBucketCount = 0;
+    int firstPeak = 0;
+    int firstPeakSize = 0;
+    for (int x = 0; x < numBuckets; x++) {
+      if (buckets[x] > firstPeakSize) {
+        firstPeak = x;
+        firstPeakSize = buckets[x];
+      }
+      if (buckets[x] > maxBucketCount) {
+        maxBucketCount = buckets[x];
+      }
+    }
+
+    // Find the second-tallest peak which is somewhat far from the tallest peak.
+    int secondPeak = 0;
+    int secondPeakScore = 0;
+    for (int x = 0; x < numBuckets; x++) {
+      int distanceToBiggest = x - firstPeak;
+      // Encourage more distant second peaks by multiplying by square of distance.
+      int score = buckets[x] * distanceToBiggest * distanceToBiggest;
+      if (score > secondPeakScore) {
+        secondPeak = x;
+        secondPeakScore = score;
+      }
+    }
+
+    // Make sure firstPeak corresponds to the black peak.
+    if (firstPeak > secondPeak) {
+      int temp = firstPeak;
+      firstPeak = secondPeak;
+      secondPeak = temp;
+    }
+
+    // If there is too little contrast in the image to pick a meaningful black point, throw rather
+    // than waste time trying to decode the image, and risk false positives.
+    if (secondPeak - firstPeak <= numBuckets >> 4) {
+      throw NotFoundException.getNotFoundInstance();
+    }
+
+    // Find a valley between them that is low and closer to the white peak.
+    int bestValley = secondPeak - 1;
+    int bestValleyScore = -1;
+    for (int x = secondPeak - 1; x > firstPeak; x--) {
+      int fromFirst = x - firstPeak;
+      int score = fromFirst * fromFirst * (secondPeak - x) * (maxBucketCount - buckets[x]);
+      if (score > bestValleyScore) {
+        bestValley = x;
+        bestValleyScore = score;
+      }
+    }
+
+    return bestValley << LUMINANCE_SHIFT;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/GridSampler.java

@@ -0,0 +1,156 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import com.google.zxing.NotFoundException;
+
+/**
+ * Implementations of this class can, given locations of finder patterns for a QR code in an
+ * image, sample the right points in the image to reconstruct the QR code, accounting for
+ * perspective distortion. It is abstracted since it is relatively expensive and should be allowed
+ * to take advantage of platform-specific optimized implementations, like Sun's Java Advanced
+ * Imaging library, but which may not be available in other environments such as J2ME, and vice
+ * versa.
+ *
+ * The implementation used can be controlled by calling {@link #setGridSampler(GridSampler)}
+ * with an instance of a class which implements this interface.
+ *
+ * @author Sean Owen
+ */
+public abstract class GridSampler {
+
+  private static GridSampler gridSampler = new DefaultGridSampler();
+
+  /**
+   * Sets the implementation of GridSampler used by the library. One global
+   * instance is stored, which may sound problematic. But, the implementation provided
+   * ought to be appropriate for the entire platform, and all uses of this library
+   * in the whole lifetime of the JVM. For instance, an Android activity can swap in
+   * an implementation that takes advantage of native platform libraries.
+   * 
+   * @param newGridSampler The platform-specific object to install.
+   */
+  public static void setGridSampler(GridSampler newGridSampler) {
+    if (newGridSampler == null) {
+      throw new IllegalArgumentException();
+    }
+    gridSampler = newGridSampler;
+  }
+
+  /**
+   * @return the current implementation of GridSampler
+   */
+  public static GridSampler getInstance() {
+    return gridSampler;
+  }
+
+  /**
+   * Samples an image for a rectangular matrix of bits of the given dimension.
+   * @param image image to sample
+   * @param dimensionX width of {@link BitMatrix} to sample from image
+   * @param dimensionY height of {@link BitMatrix} to sample from image
+   * @return {@link BitMatrix} representing a grid of points sampled from the image within a region
+   *   defined by the "from" parameters
+   * @throws NotFoundException if image can't be sampled, for example, if the transformation defined
+   *   by the given points is invalid or results in sampling outside the image boundaries
+   */
+  public abstract BitMatrix sampleGrid(BitMatrix image,
+                                       int dimensionX,
+                                       int dimensionY,
+                                       float p1ToX, float p1ToY,
+                                       float p2ToX, float p2ToY,
+                                       float p3ToX, float p3ToY,
+                                       float p4ToX, float p4ToY,
+                                       float p1FromX, float p1FromY,
+                                       float p2FromX, float p2FromY,
+                                       float p3FromX, float p3FromY,
+                                       float p4FromX, float p4FromY) throws NotFoundException;
+  
+  public abstract BitMatrix sampleGrid(BitMatrix image,
+                                       int dimensionX,
+                                       int dimensionY,
+                                       PerspectiveTransform transform) throws NotFoundException;
+
+  /**
+   * <p>Checks a set of points that have been transformed to sample points on an image against
+   * the image's dimensions to see if the point are even within the image.</p>
+   *
+   * <p>This method will actually "nudge" the endpoints back onto the image if they are found to be
+   * barely (less than 1 pixel) off the image. This accounts for imperfect detection of finder
+   * patterns in an image where the QR Code runs all the way to the image border.</p>
+   *
+   * <p>For efficiency, the method will check points from either end of the line until one is found
+   * to be within the image. Because the set of points are assumed to be linear, this is valid.</p>
+   *
+   * @param image image into which the points should map
+   * @param points actual points in x1,y1,...,xn,yn form
+   * @throws NotFoundException if an endpoint is lies outside the image boundaries
+   */
+  protected static void checkAndNudgePoints(BitMatrix image, float[] points) throws NotFoundException {
+    int width = image.getWidth();
+    int height = image.getHeight();
+    // Check and nudge points from start until we see some that are OK:
+    boolean nudged = true;
+    for (int offset = 0; offset < points.length && nudged; offset += 2) {
+      int x = (int) points[offset];
+      int y = (int) points[offset + 1];
+      if (x < -1 || x > width || y < -1 || y > height) {
+        throw NotFoundException.getNotFoundInstance();
+      }
+      nudged = false;
+      if (x == -1) {
+        points[offset] = 0.0f;
+        nudged = true;
+      } else if (x == width) {
+        points[offset] = width - 1;
+        nudged = true;
+      }
+      if (y == -1) {
+        points[offset + 1] = 0.0f;
+        nudged = true;
+      } else if (y == height) {
+        points[offset + 1] = height - 1;
+        nudged = true;
+      }
+    }
+    // Check and nudge points from end:
+    nudged = true;
+    for (int offset = points.length - 2; offset >= 0 && nudged; offset -= 2) {
+      int x = (int) points[offset];
+      int y = (int) points[offset + 1];
+      if (x < -1 || x > width || y < -1 || y > height) {
+        throw NotFoundException.getNotFoundInstance();
+      }
+      nudged = false;
+      if (x == -1) {
+        points[offset] = 0.0f;
+        nudged = true;
+      } else if (x == width) {
+        points[offset] = width - 1;
+        nudged = true;
+      }
+      if (y == -1) {
+        points[offset + 1] = 0.0f;
+        nudged = true;
+      } else if (y == height) {
+        points[offset + 1] = height - 1;
+        nudged = true;
+      }
+    }
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/HybridBinarizer.java

@@ -0,0 +1,185 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import com.google.zxing.Binarizer;
+import com.google.zxing.LuminanceSource;
+import com.google.zxing.NotFoundException;
+
+/**
+ * This class implements a local thresholding algorithm, which while slower than the
+ * GlobalHistogramBinarizer, is fairly efficient for what it does. It is designed for
+ * high frequency images of barcodes with black data on white backgrounds. For this application,
+ * it does a much better job than a global blackpoint with severe shadows and gradients.
+ * However it tends to produce artifacts on lower frequency images and is therefore not
+ * a good general purpose binarizer for uses outside ZXing.
+ *
+ * This class extends GlobalHistogramBinarizer, using the older histogram approach for 1D readers,
+ * and the newer local approach for 2D readers. 1D decoding using a per-row histogram is already
+ * inherently local, and only fails for horizontal gradients. We can revisit that problem later,
+ * but for now it was not a win to use local blocks for 1D.
+ *
+ * This Binarizer is the default for the unit tests and the recommended class for library users.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public final class HybridBinarizer extends GlobalHistogramBinarizer {
+
+  // This class uses 5x5 blocks to compute local luminance, where each block is 8x8 pixels.
+  // So this is the smallest dimension in each axis we can accept.
+  private static final int MINIMUM_DIMENSION = 40;
+
+  private BitMatrix matrix = null;
+
+  public HybridBinarizer(LuminanceSource source) {
+    super(source);
+  }
+
+  public BitMatrix getBlackMatrix() throws NotFoundException {
+    binarizeEntireImage();
+    return matrix;
+  }
+
+  public Binarizer createBinarizer(LuminanceSource source) {
+    return new HybridBinarizer(source);
+  }
+
+  // Calculates the final BitMatrix once for all requests. This could be called once from the
+  // constructor instead, but there are some advantages to doing it lazily, such as making
+  // profiling easier, and not doing heavy lifting when callers don't expect it.
+  private void binarizeEntireImage() throws NotFoundException {
+    if (matrix == null) {
+      LuminanceSource source = getLuminanceSource();
+      if (source.getWidth() >= MINIMUM_DIMENSION && source.getHeight() >= MINIMUM_DIMENSION) {
+        byte[] luminances = source.getMatrix();
+        int width = source.getWidth();
+        int height = source.getHeight();
+        int subWidth = width >> 3;
+        if ((width & 0x07) != 0) {
+          subWidth++;
+        }
+        int subHeight = height >> 3;
+        if ((height & 0x07) != 0) {
+          subHeight++;
+        }
+        int[][] blackPoints = calculateBlackPoints(luminances, subWidth, subHeight, width, height);
+
+        matrix = new BitMatrix(width, height);
+        calculateThresholdForBlock(luminances, subWidth, subHeight, width, height, blackPoints, matrix);
+      } else {
+        // If the image is too small, fall back to the global histogram approach.
+        matrix = super.getBlackMatrix();
+      }
+    }
+  }
+
+  // For each 8x8 block in the image, calculate the average black point using a 5x5 grid
+  // of the blocks around it. Also handles the corner cases (fractional blocks are computed based
+  // on the last 8 pixels in the row/column which are also used in the previous block).
+  private static void calculateThresholdForBlock(byte[] luminances, int subWidth, int subHeight,
+      int width, int height, int[][] blackPoints, BitMatrix matrix) {
+    for (int y = 0; y < subHeight; y++) {
+      int yoffset = y << 3;
+      if ((yoffset + 8) >= height) {
+        yoffset = height - 8;
+      }
+      for (int x = 0; x < subWidth; x++) {
+        int xoffset = x << 3;
+        if ((xoffset + 8) >= width) {
+            xoffset = width - 8;
+        }
+        int left = x > 1 ? x : 2;
+        left = left < subWidth - 2 ? left : subWidth - 3;
+        int top = y > 1 ? y : 2;
+        top = top < subHeight - 2 ? top : subHeight - 3;
+        int sum = 0;
+        for (int z = -2; z <= 2; z++) {
+          int[] blackRow = blackPoints[top + z];
+          sum += blackRow[left - 2];
+          sum += blackRow[left - 1];
+          sum += blackRow[left];
+          sum += blackRow[left + 1];
+          sum += blackRow[left + 2];
+        }
+        int average = sum / 25;
+        threshold8x8Block(luminances, xoffset, yoffset, average, width, matrix);
+      }
+    }
+  }
+
+  // Applies a single threshold to an 8x8 block of pixels.
+  private static void threshold8x8Block(byte[] luminances, int xoffset, int yoffset, int threshold,
+      int stride, BitMatrix matrix) {
+    for (int y = 0; y < 8; y++) {
+      int offset = (yoffset + y) * stride + xoffset;
+      for (int x = 0; x < 8; x++) {
+        int pixel = luminances[offset + x] & 0xff;
+        if (pixel < threshold) {
+          matrix.set(xoffset + x, yoffset + y);
+        }
+      }
+    }
+  }
+
+  // Calculates a single black point for each 8x8 block of pixels and saves it away.
+  private static int[][] calculateBlackPoints(byte[] luminances, int subWidth, int subHeight,
+      int width, int height) {
+    int[][] blackPoints = new int[subHeight][subWidth];
+    for (int y = 0; y < subHeight; y++) {
+      int yoffset = y << 3;
+      if ((yoffset + 8) >= height) {
+        yoffset = height - 8;
+      }
+      for (int x = 0; x < subWidth; x++) {
+        int xoffset = x << 3;
+        if ((xoffset + 8) >= width) {
+            xoffset = width - 8;
+        }
+        int sum = 0;
+        int min = 255;
+        int max = 0;
+        for (int yy = 0; yy < 8; yy++) {
+          int offset = (yoffset + yy) * width + xoffset;
+          for (int xx = 0; xx < 8; xx++) {
+            int pixel = luminances[offset + xx] & 0xff;
+            sum += pixel;
+            if (pixel < min) {
+              min = pixel;
+            }
+            if (pixel > max) {
+              max = pixel;
+            }
+          }
+        }
+
+        // If the contrast is inadequate, use half the minimum, so that this block will be
+        // treated as part of the white background, but won't drag down neighboring blocks
+        // too much.
+        int average;
+        if (max - min > 24) {
+          average = sum >> 6;
+        } else {
+          // When min == max == 0, let average be 1 so all is black
+          average = max == 0 ? 1 : min >> 1;
+        }
+        blackPoints[y][x] = average;
+      }
+    }
+    return blackPoints;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/PerspectiveTransform.java

@@ -0,0 +1,148 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+/**
+ * <p>This class implements a perspective transform in two dimensions. Given four source and four
+ * destination points, it will compute the transformation implied between them. The code is based
+ * directly upon section 3.4.2 of George Wolberg's "Digital Image Warping"; see pages 54-56.</p>
+ *
+ * @author Sean Owen
+ */
+public final class PerspectiveTransform {
+
+  private final float a11, a12, a13, a21, a22, a23, a31, a32, a33;
+
+  private PerspectiveTransform(float a11, float a21, float a31,
+                               float a12, float a22, float a32,
+                               float a13, float a23, float a33) {
+    this.a11 = a11;
+    this.a12 = a12;
+    this.a13 = a13;
+    this.a21 = a21;
+    this.a22 = a22;
+    this.a23 = a23;
+    this.a31 = a31;
+    this.a32 = a32;
+    this.a33 = a33;
+  }
+
+  public static PerspectiveTransform quadrilateralToQuadrilateral(float x0, float y0,
+                                                                  float x1, float y1,
+                                                                  float x2, float y2,
+                                                                  float x3, float y3,
+                                                                  float x0p, float y0p,
+                                                                  float x1p, float y1p,
+                                                                  float x2p, float y2p,
+                                                                  float x3p, float y3p) {
+
+    PerspectiveTransform qToS = quadrilateralToSquare(x0, y0, x1, y1, x2, y2, x3, y3);
+    PerspectiveTransform sToQ = squareToQuadrilateral(x0p, y0p, x1p, y1p, x2p, y2p, x3p, y3p);
+    return sToQ.times(qToS);
+  }
+
+  public void transformPoints(float[] points) {
+    int max = points.length;
+    float a11 = this.a11;
+    float a12 = this.a12;
+    float a13 = this.a13;
+    float a21 = this.a21;
+    float a22 = this.a22;
+    float a23 = this.a23;
+    float a31 = this.a31;
+    float a32 = this.a32;
+    float a33 = this.a33;
+    for (int i = 0; i < max; i += 2) {
+      float x = points[i];
+      float y = points[i + 1];
+      float denominator = a13 * x + a23 * y + a33;
+      points[i] = (a11 * x + a21 * y + a31) / denominator;
+      points[i + 1] = (a12 * x + a22 * y + a32) / denominator;
+    }
+  }
+
+  /** Convenience method, not optimized for performance. */
+  public void transformPoints(float[] xValues, float[] yValues) {
+    int n = xValues.length;
+    for (int i = 0; i < n; i ++) {
+      float x = xValues[i];
+      float y = yValues[i];
+      float denominator = a13 * x + a23 * y + a33;
+      xValues[i] = (a11 * x + a21 * y + a31) / denominator;
+      yValues[i] = (a12 * x + a22 * y + a32) / denominator;
+    }
+  }
+
+  public static PerspectiveTransform squareToQuadrilateral(float x0, float y0,
+                                                           float x1, float y1,
+                                                           float x2, float y2,
+                                                           float x3, float y3) {
+    float dy2 = y3 - y2;
+    float dy3 = y0 - y1 + y2 - y3;
+    if (dy2 == 0.0f && dy3 == 0.0f) {
+      return new PerspectiveTransform(x1 - x0, x2 - x1, x0,
+          y1 - y0, y2 - y1, y0,
+          0.0f, 0.0f, 1.0f);
+    } else {
+      float dx1 = x1 - x2;
+      float dx2 = x3 - x2;
+      float dx3 = x0 - x1 + x2 - x3;
+      float dy1 = y1 - y2;
+      float denominator = dx1 * dy2 - dx2 * dy1;
+      float a13 = (dx3 * dy2 - dx2 * dy3) / denominator;
+      float a23 = (dx1 * dy3 - dx3 * dy1) / denominator;
+      return new PerspectiveTransform(x1 - x0 + a13 * x1, x3 - x0 + a23 * x3, x0,
+          y1 - y0 + a13 * y1, y3 - y0 + a23 * y3, y0,
+          a13, a23, 1.0f);
+    }
+  }
+
+  public static PerspectiveTransform quadrilateralToSquare(float x0, float y0,
+                                                           float x1, float y1,
+                                                           float x2, float y2,
+                                                           float x3, float y3) {
+    // Here, the adjoint serves as the inverse:
+    return squareToQuadrilateral(x0, y0, x1, y1, x2, y2, x3, y3).buildAdjoint();
+  }
+
+  PerspectiveTransform buildAdjoint() {
+    // Adjoint is the transpose of the cofactor matrix:
+    return new PerspectiveTransform(a22 * a33 - a23 * a32,
+        a23 * a31 - a21 * a33,
+        a21 * a32 - a22 * a31,
+        a13 * a32 - a12 * a33,
+        a11 * a33 - a13 * a31,
+        a12 * a31 - a11 * a32,
+        a12 * a23 - a13 * a22,
+        a13 * a21 - a11 * a23,
+        a11 * a22 - a12 * a21);
+  }
+
+  PerspectiveTransform times(PerspectiveTransform other) {
+    return new PerspectiveTransform(a11 * other.a11 + a21 * other.a12 + a31 * other.a13,
+        a11 * other.a21 + a21 * other.a22 + a31 * other.a23,
+        a11 * other.a31 + a21 * other.a32 + a31 * other.a33,
+        a12 * other.a11 + a22 * other.a12 + a32 * other.a13,
+        a12 * other.a21 + a22 * other.a22 + a32 * other.a23,
+        a12 * other.a31 + a22 * other.a32 + a32 * other.a33,
+        a13 * other.a11 + a23 * other.a12 + a33 * other.a13,
+        a13 * other.a21 + a23 * other.a22 + a33 * other.a23,
+        a13 * other.a31 + a23 * other.a32 + a33 * other.a33);
+
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/StringUtils.java

@@ -0,0 +1,192 @@
+/*
+ * Copyright (C) 2010 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import java.util.Hashtable;
+
+import com.google.zxing.DecodeHintType;
+
+/**
+ * Common string-related functions.
+ *
+ * @author Sean Owen
+ */
+public final class StringUtils {
+
+  private static final String PLATFORM_DEFAULT_ENCODING =
+      System.getProperty("file.encoding");
+  public static final String SHIFT_JIS = "SJIS";
+  public static final String GB2312 = "GB2312";
+  private static final String EUC_JP = "EUC_JP";
+  private static final String UTF8 = "UTF8";
+  private static final String ISO88591 = "ISO8859_1";
+  private static final boolean ASSUME_SHIFT_JIS =
+      SHIFT_JIS.equalsIgnoreCase(PLATFORM_DEFAULT_ENCODING) ||
+      EUC_JP.equalsIgnoreCase(PLATFORM_DEFAULT_ENCODING);
+
+  private StringUtils() {}
+
+  /**
+   * @param bytes bytes encoding a string, whose encoding should be guessed
+   * @param hints decode hints if applicable
+   * @return name of guessed encoding; at the moment will only guess one of:
+   *  {@link #SHIFT_JIS}, {@link #UTF8}, {@link #ISO88591}, or the platform
+   *  default encoding if none of these can possibly be correct
+   */
+  public static String guessEncoding(byte[] bytes, Hashtable hints) {
+    if (hints != null) {
+      String characterSet = (String) hints.get(DecodeHintType.CHARACTER_SET);
+      if (characterSet != null) {
+        return characterSet;
+      }
+    }
+    // Does it start with the UTF-8 byte order mark? then guess it's UTF-8
+    if (bytes.length > 3 &&
+        bytes[0] == (byte) 0xEF &&
+        bytes[1] == (byte) 0xBB &&
+        bytes[2] == (byte) 0xBF) {
+      return UTF8;
+    }
+    // For now, merely tries to distinguish ISO-8859-1, UTF-8 and Shift_JIS,
+    // which should be by far the most common encodings. ISO-8859-1
+    // should not have bytes in the 0x80 - 0x9F range, while Shift_JIS
+    // uses this as a first byte of a two-byte character. If we see this
+    // followed by a valid second byte in Shift_JIS, assume it is Shift_JIS.
+    // If we see something else in that second byte, we'll make the risky guess
+    // that it's UTF-8.
+    int length = bytes.length;
+    boolean canBeISO88591 = true;
+    boolean canBeShiftJIS = true;
+    boolean canBeUTF8 = true;
+    int utf8BytesLeft = 0;
+    int maybeDoubleByteCount = 0;
+    int maybeSingleByteKatakanaCount = 0;
+    boolean sawLatin1Supplement = false;
+    boolean sawUTF8Start = false;
+    boolean lastWasPossibleDoubleByteStart = false;
+
+    for (int i = 0;
+         i < length && (canBeISO88591 || canBeShiftJIS || canBeUTF8);
+         i++) {
+
+      int value = bytes[i] & 0xFF;
+
+      // UTF-8 stuff
+      if (value >= 0x80 && value <= 0xBF) {
+        if (utf8BytesLeft > 0) {
+          utf8BytesLeft--;
+        }
+      } else {
+        if (utf8BytesLeft > 0) {
+          canBeUTF8 = false;
+        }
+        if (value >= 0xC0 && value <= 0xFD) {
+          sawUTF8Start = true;
+          int valueCopy = value;
+          while ((valueCopy & 0x40) != 0) {
+            utf8BytesLeft++;
+            valueCopy <<= 1;
+          }
+        }
+      }
+
+      // ISO-8859-1 stuff
+
+      if ((value == 0xC2 || value == 0xC3) && i < length - 1) {
+        // This is really a poor hack. The slightly more exotic characters people might want to put in
+        // a QR Code, by which I mean the Latin-1 supplement characters (e.g. u-umlaut) have encodings
+        // that start with 0xC2 followed by [0xA0,0xBF], or start with 0xC3 followed by [0x80,0xBF].
+        int nextValue = bytes[i + 1] & 0xFF;
+        if (nextValue <= 0xBF &&
+            ((value == 0xC2 && nextValue >= 0xA0) || (value == 0xC3 && nextValue >= 0x80))) {
+          sawLatin1Supplement = true;
+        }
+      }
+      if (value >= 0x7F && value <= 0x9F) {
+        canBeISO88591 = false;
+      }
+
+      // Shift_JIS stuff
+
+      if (value >= 0xA1 && value <= 0xDF) {
+        // count the number of characters that might be a Shift_JIS single-byte Katakana character
+        if (!lastWasPossibleDoubleByteStart) {
+          maybeSingleByteKatakanaCount++;
+        }
+      }
+      if (!lastWasPossibleDoubleByteStart &&
+          ((value >= 0xF0 && value <= 0xFF) || value == 0x80 || value == 0xA0)) {
+        canBeShiftJIS = false;
+      }
+      if ((value >= 0x81 && value <= 0x9F) || (value >= 0xE0 && value <= 0xEF)) {
+        // These start double-byte characters in Shift_JIS. Let's see if it's followed by a valid
+        // second byte.
+        if (lastWasPossibleDoubleByteStart) {
+          // If we just checked this and the last byte for being a valid double-byte
+          // char, don't check starting on this byte. If this and the last byte
+          // formed a valid pair, then this shouldn't be checked to see if it starts
+          // a double byte pair of course.
+          lastWasPossibleDoubleByteStart = false;
+        } else {
+          // ... otherwise do check to see if this plus the next byte form a valid
+          // double byte pair encoding a character.
+          lastWasPossibleDoubleByteStart = true;
+          if (i >= bytes.length - 1) {
+            canBeShiftJIS = false;
+          } else {
+            int nextValue = bytes[i + 1] & 0xFF;
+            if (nextValue < 0x40 || nextValue > 0xFC) {
+              canBeShiftJIS = false;
+            } else {
+              maybeDoubleByteCount++;
+            }
+            // There is some conflicting information out there about which bytes can follow which in
+            // double-byte Shift_JIS characters. The rule above seems to be the one that matches practice.
+          }
+        }
+      } else {
+        lastWasPossibleDoubleByteStart = false;
+      }
+    }
+    if (utf8BytesLeft > 0) {
+      canBeUTF8 = false;
+    }
+
+    // Easy -- if assuming Shift_JIS and no evidence it can't be, done
+    if (canBeShiftJIS && ASSUME_SHIFT_JIS) {
+      return SHIFT_JIS;
+    }
+    if (canBeUTF8 && sawUTF8Start) {
+      return UTF8;
+    }
+    // Distinguishing Shift_JIS and ISO-8859-1 can be a little tough. The crude heuristic is:
+    // - If we saw
+    //   - at least 3 bytes that starts a double-byte value (bytes that are rare in ISO-8859-1), or
+    //   - over 5% of bytes could be single-byte Katakana (also rare in ISO-8859-1),
+    // - and, saw no sequences that are invalid in Shift_JIS, then we conclude Shift_JIS
+    if (canBeShiftJIS && (maybeDoubleByteCount >= 3 || 20 * maybeSingleByteKatakanaCount > length)) {
+      return SHIFT_JIS;
+    }
+    // Otherwise, we default to ISO-8859-1 unless we know it can't be
+    if (!sawLatin1Supplement && canBeISO88591) {
+      return ISO88591;
+    }
+    // Otherwise, we take a wild guess with platform encoding
+    return PLATFORM_DEFAULT_ENCODING;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/detector/MonochromeRectangleDetector.java

@@ -0,0 +1,209 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common.detector;
+
+import com.google.zxing.NotFoundException;
+import com.google.zxing.ResultPoint;
+import com.google.zxing.common.BitMatrix;
+
+/**
+ * <p>A somewhat generic detector that looks for a barcode-like rectangular region within an image.
+ * It looks within a mostly white region of an image for a region of black and white, but mostly
+ * black. It returns the four corners of the region, as best it can determine.</p>
+ *
+ * @author Sean Owen
+ */
+public final class MonochromeRectangleDetector {
+
+  private static final int MAX_MODULES = 32;
+
+  private final BitMatrix image;
+
+  public MonochromeRectangleDetector(BitMatrix image) {
+    this.image = image;
+  }
+
+  /**
+   * <p>Detects a rectangular region of black and white -- mostly black -- with a region of mostly
+   * white, in an image.</p>
+   *
+   * @return {@link ResultPoint}[] describing the corners of the rectangular region. The first and
+   *  last points are opposed on the diagonal, as are the second and third. The first point will be
+   *  the topmost point and the last, the bottommost. The second point will be leftmost and the
+   *  third, the rightmost
+   * @throws NotFoundException if no Data Matrix Code can be found
+   */
+  public ResultPoint[] detect() throws NotFoundException {
+    int height = image.getHeight();
+    int width = image.getWidth();
+    int halfHeight = height >> 1;
+    int halfWidth = width >> 1;
+    int deltaY = Math.max(1, height / (MAX_MODULES << 3));
+    int deltaX = Math.max(1, width / (MAX_MODULES << 3));
+
+    int top = 0;
+    int bottom = height;
+    int left = 0;
+    int right = width;
+    ResultPoint pointA = findCornerFromCenter(halfWidth, 0, left, right,
+        halfHeight, -deltaY, top, bottom, halfWidth >> 1);
+    top = (int) pointA.getY() - 1;
+    ResultPoint pointB = findCornerFromCenter(halfWidth, -deltaX, left, right,
+        halfHeight, 0, top, bottom, halfHeight >> 1);
+    left = (int) pointB.getX() - 1;
+    ResultPoint pointC = findCornerFromCenter(halfWidth, deltaX, left, right,
+        halfHeight, 0, top, bottom, halfHeight >> 1);
+    right = (int) pointC.getX() + 1;
+    ResultPoint pointD = findCornerFromCenter(halfWidth, 0, left, right,
+        halfHeight, deltaY, top, bottom, halfWidth >> 1);
+    bottom = (int) pointD.getY() + 1;
+
+    // Go try to find point A again with better information -- might have been off at first.
+    pointA = findCornerFromCenter(halfWidth, 0, left, right,
+        halfHeight, -deltaY, top, bottom, halfWidth >> 2);
+
+    return new ResultPoint[] { pointA, pointB, pointC, pointD };
+  }
+
+  /**
+   * Attempts to locate a corner of the barcode by scanning up, down, left or right from a center
+   * point which should be within the barcode.
+   *
+   * @param centerX center's x component (horizontal)
+   * @param deltaX same as deltaY but change in x per step instead
+   * @param left minimum value of x
+   * @param right maximum value of x
+   * @param centerY center's y component (vertical)
+   * @param deltaY change in y per step. If scanning up this is negative; down, positive;
+   *  left or right, 0
+   * @param top minimum value of y to search through (meaningless when di == 0)
+   * @param bottom maximum value of y
+   * @param maxWhiteRun maximum run of white pixels that can still be considered to be within
+   *  the barcode
+   * @return a {@link com.google.zxing.ResultPoint} encapsulating the corner that was found
+   * @throws NotFoundException if such a point cannot be found
+   */
+  private ResultPoint findCornerFromCenter(int centerX, int deltaX, int left, int right,
+      int centerY, int deltaY, int top, int bottom, int maxWhiteRun) throws NotFoundException {
+    int[] lastRange = null;
+    for (int y = centerY, x = centerX;
+         y < bottom && y >= top && x < right && x >= left;
+         y += deltaY, x += deltaX) {
+      int[] range;
+      if (deltaX == 0) {
+        // horizontal slices, up and down
+        range = blackWhiteRange(y, maxWhiteRun, left, right, true);
+      } else {
+        // vertical slices, left and right
+        range = blackWhiteRange(x, maxWhiteRun, top, bottom, false);
+      }
+      if (range == null) {
+        if (lastRange == null) {
+          throw NotFoundException.getNotFoundInstance();
+        }
+        // lastRange was found
+        if (deltaX == 0) {
+          int lastY = y - deltaY;
+          if (lastRange[0] < centerX) {
+            if (lastRange[1] > centerX) {
+              // straddle, choose one or the other based on direction
+              return new ResultPoint(deltaY > 0 ? lastRange[0] : lastRange[1], lastY);
+            }
+            return new ResultPoint(lastRange[0], lastY);
+          } else {
+            return new ResultPoint(lastRange[1], lastY);
+          }
+        } else {
+          int lastX = x - deltaX;
+          if (lastRange[0] < centerY) {
+            if (lastRange[1] > centerY) {
+              return new ResultPoint(lastX, deltaX < 0 ? lastRange[0] : lastRange[1]);
+            }
+            return new ResultPoint(lastX, lastRange[0]);
+          } else {
+            return new ResultPoint(lastX, lastRange[1]);
+          }
+        }
+      }
+      lastRange = range;
+    }
+    throw NotFoundException.getNotFoundInstance();
+  }
+
+  /**
+   * Computes the start and end of a region of pixels, either horizontally or vertically, that could
+   * be part of a Data Matrix barcode.
+   *
+   * @param fixedDimension if scanning horizontally, this is the row (the fixed vertical location)
+   *  where we are scanning. If scanning vertically it's the column, the fixed horizontal location
+   * @param maxWhiteRun largest run of white pixels that can still be considered part of the
+   *  barcode region
+   * @param minDim minimum pixel location, horizontally or vertically, to consider
+   * @param maxDim maximum pixel location, horizontally or vertically, to consider
+   * @param horizontal if true, we're scanning left-right, instead of up-down
+   * @return int[] with start and end of found range, or null if no such range is found
+   *  (e.g. only white was found)
+   */
+  private int[] blackWhiteRange(int fixedDimension, int maxWhiteRun, int minDim, int maxDim,
+      boolean horizontal) {
+
+    int center = (minDim + maxDim) >> 1;
+
+    // Scan left/up first
+    int start = center;
+    while (start >= minDim) {
+      if (horizontal ? image.get(start, fixedDimension) : image.get(fixedDimension, start)) {
+        start--;
+      } else {
+        int whiteRunStart = start;
+        do {
+          start--;
+        } while (start >= minDim && !(horizontal ? image.get(start, fixedDimension) :
+            image.get(fixedDimension, start)));
+        int whiteRunSize = whiteRunStart - start;
+        if (start < minDim || whiteRunSize > maxWhiteRun) {
+          start = whiteRunStart;
+          break;
+        }
+      }
+    }
+    start++;
+
+    // Then try right/down
+    int end = center;
+    while (end < maxDim) {
+      if (horizontal ? image.get(end, fixedDimension) : image.get(fixedDimension, end)) {
+        end++;
+      } else {
+        int whiteRunStart = end;
+        do {
+          end++;
+        } while (end < maxDim && !(horizontal ? image.get(end, fixedDimension) :
+            image.get(fixedDimension, end)));
+        int whiteRunSize = end - whiteRunStart;
+        if (end >= maxDim || whiteRunSize > maxWhiteRun) {
+          end = whiteRunStart;
+          break;
+        }
+      }
+    }
+    end--;
+
+    return end > start ? new int[]{start, end} : null;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/detector/WhiteRectangleDetector.java

@@ -0,0 +1,347 @@
+/*
+ * Copyright 2010 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common.detector;
+
+import com.google.zxing.NotFoundException;
+import com.google.zxing.ResultPoint;
+import com.google.zxing.common.BitMatrix;
+
+/**
+ * <p>
+ * Detects a candidate barcode-like rectangular region within an image. It
+ * starts around the center of the image, increases the size of the candidate
+ * region until it finds a white rectangular region. By keeping track of the
+ * last black points it encountered, it determines the corners of the barcode.
+ * </p>
+ *
+ * @author David Olivier
+ */
+public final class WhiteRectangleDetector {
+
+  private static final int INIT_SIZE = 30;
+  private static final int CORR = 1;
+
+  private final BitMatrix image;
+  private final int height;
+  private final int width;
+  private final int leftInit;
+  private final int rightInit;
+  private final int downInit;
+  private final int upInit;
+
+  /**
+   * @throws NotFoundException if image is too small
+   */
+  public WhiteRectangleDetector(BitMatrix image) throws NotFoundException {
+    this.image = image;
+    height = image.getHeight();
+    width = image.getWidth();
+    leftInit = (width - INIT_SIZE) >> 1;
+    rightInit = (width + INIT_SIZE) >> 1;
+    upInit = (height - INIT_SIZE) >> 1;
+    downInit = (height + INIT_SIZE) >> 1;
+    if (upInit < 0 || leftInit < 0 || downInit >= height || rightInit >= width) {
+      throw NotFoundException.getNotFoundInstance();
+    }
+  }
+
+  /**
+   * @throws NotFoundException if image is too small
+   */
+  public WhiteRectangleDetector(BitMatrix image, int initSize, int x, int y) throws NotFoundException {
+    this.image = image;
+    height = image.getHeight();
+    width = image.getWidth();
+    int halfsize = initSize >> 1;
+    leftInit = x - halfsize;
+    rightInit = x + halfsize;
+    upInit = y - halfsize;
+    downInit = y + halfsize;
+    if (upInit < 0 || leftInit < 0 || downInit >= height || rightInit >= width) {
+      throw NotFoundException.getNotFoundInstance();
+    }
+  }
+
+  /**
+   * <p>
+   * Detects a candidate barcode-like rectangular region within an image. It
+   * starts around the center of the image, increases the size of the candidate
+   * region until it finds a white rectangular region.
+   * </p>
+   *
+   * @return {@link ResultPoint[]} describing the corners of the rectangular
+   *         region. The first and last points are opposed on the diagonal, as
+   *         are the second and third. The first point will be the topmost
+   *         point and the last, the bottommost. The second point will be
+   *         leftmost and the third, the rightmost
+   * @throws NotFoundException if no Data Matrix Code can be found
+   */
+  public ResultPoint[] detect() throws NotFoundException {
+
+    int left = leftInit;
+    int right = rightInit;
+    int up = upInit;
+    int down = downInit;
+    boolean sizeExceeded = false;
+    boolean aBlackPointFoundOnBorder = true;
+    boolean atLeastOneBlackPointFoundOnBorder = false;
+
+    while (aBlackPointFoundOnBorder) {
+
+      aBlackPointFoundOnBorder = false;
+
+      // .....
+      // .   |
+      // .....
+      boolean rightBorderNotWhite = true;
+      while (rightBorderNotWhite && right < width) {
+        rightBorderNotWhite = containsBlackPoint(up, down, right, false);
+        if (rightBorderNotWhite) {
+          right++;
+          aBlackPointFoundOnBorder = true;
+        }
+      }
+
+      if (right >= width) {
+        sizeExceeded = true;
+        break;
+      }
+
+      // .....
+      // .   .
+      // .___.
+      boolean bottomBorderNotWhite = true;
+      while (bottomBorderNotWhite && down < height) {
+        bottomBorderNotWhite = containsBlackPoint(left, right, down, true);
+        if (bottomBorderNotWhite) {
+          down++;
+          aBlackPointFoundOnBorder = true;
+        }
+      }
+
+      if (down >= height) {
+        sizeExceeded = true;
+        break;
+      }
+
+      // .....
+      // |   .
+      // .....
+      boolean leftBorderNotWhite = true;
+      while (leftBorderNotWhite && left >= 0) {
+        leftBorderNotWhite = containsBlackPoint(up, down, left, false);
+        if (leftBorderNotWhite) {
+          left--;
+          aBlackPointFoundOnBorder = true;
+        }
+      }
+
+      if (left < 0) {
+        sizeExceeded = true;
+        break;
+      }
+
+      // .___.
+      // .   .
+      // .....
+      boolean topBorderNotWhite = true;
+      while (topBorderNotWhite && up >= 0) {
+        topBorderNotWhite = containsBlackPoint(left, right, up, true);
+        if (topBorderNotWhite) {
+          up--;
+          aBlackPointFoundOnBorder = true;
+        }
+      }
+
+      if (up < 0) {
+        sizeExceeded = true;
+        break;
+      }
+
+      if (aBlackPointFoundOnBorder) {
+        atLeastOneBlackPointFoundOnBorder = true;
+      }
+
+    }
+
+    if (!sizeExceeded && atLeastOneBlackPointFoundOnBorder) {
+
+      int maxSize = right - left;
+
+      ResultPoint z = null;
+      for (int i = 1; i < maxSize; i++) {
+        z = getBlackPointOnSegment(left, down - i, left + i, down);
+        if (z != null) {
+          break;
+        }
+      }
+
+      if (z == null) {
+        throw NotFoundException.getNotFoundInstance();
+      }
+
+      ResultPoint t = null;
+      //go down right
+      for (int i = 1; i < maxSize; i++) {
+        t = getBlackPointOnSegment(left, up + i, left + i, up);
+        if (t != null) {
+          break;
+        }
+      }
+
+      if (t == null) {
+        throw NotFoundException.getNotFoundInstance();
+      }
+
+      ResultPoint x = null;
+      //go down left
+      for (int i = 1; i < maxSize; i++) {
+        x = getBlackPointOnSegment(right, up + i, right - i, up);
+        if (x != null) {
+          break;
+        }
+      }
+
+      if (x == null) {
+        throw NotFoundException.getNotFoundInstance();
+      }
+
+      ResultPoint y = null;
+      //go up left
+      for (int i = 1; i < maxSize; i++) {
+        y = getBlackPointOnSegment(right, down - i, right - i, down);
+        if (y != null) {
+          break;
+        }
+      }
+
+      if (y == null) {
+        throw NotFoundException.getNotFoundInstance();
+      }
+
+      return centerEdges(y, z, x, t);
+
+    } else {
+      throw NotFoundException.getNotFoundInstance();
+    }
+  }
+
+  /**
+   * Ends up being a bit faster than Math.round(). This merely rounds its
+   * argument to the nearest int, where x.5 rounds up.
+   */
+  private static int round(float d) {
+    return (int) (d + 0.5f);
+  }
+
+  private ResultPoint getBlackPointOnSegment(float aX, float aY, float bX, float bY) {
+    int dist = distanceL2(aX, aY, bX, bY);
+    float xStep = (bX - aX) / dist;
+    float yStep = (bY - aY) / dist;
+
+    for (int i = 0; i < dist; i++) {
+      int x = round(aX + i * xStep);
+      int y = round(aY + i * yStep);
+      if (image.get(x, y)) {
+        return new ResultPoint(x, y);
+      }
+    }
+    return null;
+  }
+
+  private static int distanceL2(float aX, float aY, float bX, float bY) {
+    float xDiff = aX - bX;
+    float yDiff = aY - bY;
+    return round((float) Math.sqrt(xDiff * xDiff + yDiff * yDiff));
+  }
+
+  /**
+   * recenters the points of a constant distance towards the center
+   *
+   * @param y bottom most point
+   * @param z left most point
+   * @param x right most point
+   * @param t top most point
+   * @return {@link ResultPoint}[] describing the corners of the rectangular
+   *         region. The first and last points are opposed on the diagonal, as
+   *         are the second and third. The first point will be the topmost
+   *         point and the last, the bottommost. The second point will be
+   *         leftmost and the third, the rightmost
+   */
+  private ResultPoint[] centerEdges(ResultPoint y, ResultPoint z,
+                                    ResultPoint x, ResultPoint t) {
+
+    //
+    //       t            t
+    //  z                      x
+    //        x    OR    z
+    //   y                    y
+    //
+
+    float yi = y.getX();
+    float yj = y.getY();
+    float zi = z.getX();
+    float zj = z.getY();
+    float xi = x.getX();
+    float xj = x.getY();
+    float ti = t.getX();
+    float tj = t.getY();
+
+    if (yi < width / 2) {
+      return new ResultPoint[]{
+          new ResultPoint(ti - CORR, tj + CORR),
+          new ResultPoint(zi + CORR, zj + CORR),
+          new ResultPoint(xi - CORR, xj - CORR),
+          new ResultPoint(yi + CORR, yj - CORR)};
+    } else {
+      return new ResultPoint[]{
+          new ResultPoint(ti + CORR, tj + CORR),
+          new ResultPoint(zi + CORR, zj - CORR),
+          new ResultPoint(xi - CORR, xj + CORR),
+          new ResultPoint(yi - CORR, yj - CORR)};
+    }
+  }
+
+  /**
+   * Determines whether a segment contains a black point
+   *
+   * @param a          min value of the scanned coordinate
+   * @param b          max value of the scanned coordinate
+   * @param fixed      value of fixed coordinate
+   * @param horizontal set to true if scan must be horizontal, false if vertical
+   * @return true if a black point has been found, else false.
+   */
+  private boolean containsBlackPoint(int a, int b, int fixed, boolean horizontal) {
+
+    if (horizontal) {
+      for (int x = a; x <= b; x++) {
+        if (image.get(x, fixed)) {
+          return true;
+        }
+      }
+    } else {
+      for (int y = a; y <= b; y++) {
+        if (image.get(fixed, y)) {
+          return true;
+        }
+      }
+    }
+
+    return false;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/reedsolomon/GenericGF.java

@@ -0,0 +1,188 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common.reedsolomon;
+
+/**
+ * <p>This class contains utility methods for performing mathematical operations over
+ * the Galois Fields. Operations use a given primitive polynomial in calculations.</p>
+ *
+ * <p>Throughout this package, elements of the GF are represented as an <code>int</code>
+ * for convenience and speed (but at the cost of memory).
+ * </p>
+ *
+ * @author Sean Owen
+ * @author David Olivier
+ */
+public final class GenericGF {
+
+  public static final GenericGF AZTEC_DATA_12 = new GenericGF(0x1069, 4096); // x^12 + x^6 + x^5 + x^3 + 1
+  public static final GenericGF AZTEC_DATA_10 = new GenericGF(0x409, 1024); // x^10 + x^3 + 1
+  public static final GenericGF AZTEC_DATA_6 = new GenericGF(0x43, 64); // x^6 + x + 1
+  public static final GenericGF AZTEC_PARAM = new GenericGF(0x13, 16); // x^4 + x + 1
+  public static final GenericGF QR_CODE_FIELD_256 = new GenericGF(0x011D, 256); // x^8 + x^4 + x^3 + x^2 + 1
+  public static final GenericGF DATA_MATRIX_FIELD_256 = new GenericGF(0x012D, 256); // x^8 + x^5 + x^3 + x^2 + 1
+  public static final GenericGF AZTEC_DATA_8 = DATA_MATRIX_FIELD_256;
+
+  private static final int INITIALIZATION_THRESHOLD = 0;
+
+  private int[] expTable;
+  private int[] logTable;
+  private GenericGFPoly zero;
+  private GenericGFPoly one;
+  private final int size;
+  private final int primitive;
+  private boolean initialized = false;
+
+  /**
+   * Create a representation of GF(size) using the given primitive polynomial.
+   *
+   * @param primitive irreducible polynomial whose coefficients are represented by
+   *  the bits of an int, where the least-significant bit represents the constant
+   *  coefficient
+   */
+  public GenericGF(int primitive, int size) {
+  	this.primitive = primitive;
+    this.size = size;
+    
+    if (size <= INITIALIZATION_THRESHOLD){
+    	initialize();
+    }
+  }
+
+  private void initialize(){
+    expTable = new int[size];
+    logTable = new int[size];
+    int x = 1;
+    for (int i = 0; i < size; i++) {
+      expTable[i] = x;
+      x <<= 1; // x = x * 2; we're assuming the generator alpha is 2
+      if (x >= size) {
+        x ^= primitive;
+        x &= size-1;
+      }
+    }
+    for (int i = 0; i < size-1; i++) {
+      logTable[expTable[i]] = i;
+    }
+    // logTable[0] == 0 but this should never be used
+    zero = new GenericGFPoly(this, new int[]{0});
+    one = new GenericGFPoly(this, new int[]{1});
+    initialized = true;
+  }
+  
+  private void checkInit(){
+  	if (!initialized) {
+      initialize();
+    }
+  }
+  
+  GenericGFPoly getZero() {
+  	checkInit();
+  	
+    return zero;
+  }
+
+  GenericGFPoly getOne() {
+  	checkInit();
+  	
+    return one;
+  }
+
+  /**
+   * @return the monomial representing coefficient * x^degree
+   */
+  GenericGFPoly buildMonomial(int degree, int coefficient) {
+  	checkInit();
+  	
+    if (degree < 0) {
+      throw new IllegalArgumentException();
+    }
+    if (coefficient == 0) {
+      return zero;
+    }
+    int[] coefficients = new int[degree + 1];
+    coefficients[0] = coefficient;
+    return new GenericGFPoly(this, coefficients);
+  }
+
+  /**
+   * Implements both addition and subtraction -- they are the same in GF(size).
+   *
+   * @return sum/difference of a and b
+   */
+  static int addOrSubtract(int a, int b) {
+    return a ^ b;
+  }
+
+  /**
+   * @return 2 to the power of a in GF(size)
+   */
+  int exp(int a) {
+  	checkInit();
+  	
+    return expTable[a];
+  }
+
+  /**
+   * @return base 2 log of a in GF(size)
+   */
+  int log(int a) {
+  	checkInit();
+  	
+    if (a == 0) {
+      throw new IllegalArgumentException();
+    }
+    return logTable[a];
+  }
+
+  /**
+   * @return multiplicative inverse of a
+   */
+  int inverse(int a) {
+  	checkInit();
+  	
+    if (a == 0) {
+      throw new ArithmeticException();
+    }
+    return expTable[size - logTable[a] - 1];
+  }
+
+  /**
+   * @param a
+   * @param b
+   * @return product of a and b in GF(size)
+   */
+  int multiply(int a, int b) {
+  	checkInit();
+  	
+    if (a == 0 || b == 0) {
+      return 0;
+    }
+    
+    if (a<0 || b <0 || a>=size || b >=size){
+    	a++;
+    }
+    
+    int logSum = logTable[a] + logTable[b];
+    return expTable[(logSum % size) + logSum / size];
+  }
+
+  public int getSize(){
+  	return size;
+  }
+  
+}

OpenPGP-Keychain/src/com/google/zxing/common/reedsolomon/GenericGFPoly.java

@@ -0,0 +1,263 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common.reedsolomon;
+
+/**
+ * <p>Represents a polynomial whose coefficients are elements of a GF.
+ * Instances of this class are immutable.</p>
+ *
+ * <p>Much credit is due to William Rucklidge since portions of this code are an indirect
+ * port of his C++ Reed-Solomon implementation.</p>
+ *
+ * @author Sean Owen
+ */
+final class GenericGFPoly {
+
+  private final GenericGF field;
+  private final int[] coefficients;
+
+  /**
+   * @param field the {@link GenericGF} instance representing the field to use
+   * to perform computations
+   * @param coefficients coefficients as ints representing elements of GF(size), arranged
+   * from most significant (highest-power term) coefficient to least significant
+   * @throws IllegalArgumentException if argument is null or empty,
+   * or if leading coefficient is 0 and this is not a
+   * constant polynomial (that is, it is not the monomial "0")
+   */
+  GenericGFPoly(GenericGF field, int[] coefficients) {
+    if (coefficients == null || coefficients.length == 0) {
+      throw new IllegalArgumentException();
+    }
+    this.field = field;
+    int coefficientsLength = coefficients.length;
+    if (coefficientsLength > 1 && coefficients[0] == 0) {
+      // Leading term must be non-zero for anything except the constant polynomial "0"
+      int firstNonZero = 1;
+      while (firstNonZero < coefficientsLength && coefficients[firstNonZero] == 0) {
+        firstNonZero++;
+      }
+      if (firstNonZero == coefficientsLength) {
+        this.coefficients = field.getZero().coefficients;
+      } else {
+        this.coefficients = new int[coefficientsLength - firstNonZero];
+        System.arraycopy(coefficients,
+            firstNonZero,
+            this.coefficients,
+            0,
+            this.coefficients.length);
+      }
+    } else {
+      this.coefficients = coefficients;
+    }
+  }
+
+  int[] getCoefficients() {
+    return coefficients;
+  }
+
+  /**
+   * @return degree of this polynomial
+   */
+  int getDegree() {
+    return coefficients.length - 1;
+  }
+
+  /**
+   * @return true iff this polynomial is the monomial "0"
+   */
+  boolean isZero() {
+    return coefficients[0] == 0;
+  }
+
+  /**
+   * @return coefficient of x^degree term in this polynomial
+   */
+  int getCoefficient(int degree) {
+    return coefficients[coefficients.length - 1 - degree];
+  }
+
+  /**
+   * @return evaluation of this polynomial at a given point
+   */
+  int evaluateAt(int a) {
+    if (a == 0) {
+      // Just return the x^0 coefficient
+      return getCoefficient(0);
+    }
+    int size = coefficients.length;
+    if (a == 1) {
+      // Just the sum of the coefficients
+      int result = 0;
+      for (int i = 0; i < size; i++) {
+        result = GenericGF.addOrSubtract(result, coefficients[i]);
+      }
+      return result;
+    }
+    int result = coefficients[0];
+    for (int i = 1; i < size; i++) {
+      result = GenericGF.addOrSubtract(field.multiply(a, result), coefficients[i]);
+    }
+    return result;
+  }
+
+  GenericGFPoly addOrSubtract(GenericGFPoly other) {
+    if (!field.equals(other.field)) {
+      throw new IllegalArgumentException("GenericGFPolys do not have same GenericGF field");
+    }
+    if (isZero()) {
+      return other;
+    }
+    if (other.isZero()) {
+      return this;
+    }
+
+    int[] smallerCoefficients = this.coefficients;
+    int[] largerCoefficients = other.coefficients;
+    if (smallerCoefficients.length > largerCoefficients.length) {
+      int[] temp = smallerCoefficients;
+      smallerCoefficients = largerCoefficients;
+      largerCoefficients = temp;
+    }
+    int[] sumDiff = new int[largerCoefficients.length];
+    int lengthDiff = largerCoefficients.length - smallerCoefficients.length;
+    // Copy high-order terms only found in higher-degree polynomial's coefficients
+    System.arraycopy(largerCoefficients, 0, sumDiff, 0, lengthDiff);
+
+    for (int i = lengthDiff; i < largerCoefficients.length; i++) {
+      sumDiff[i] = GenericGF.addOrSubtract(smallerCoefficients[i - lengthDiff], largerCoefficients[i]);
+    }
+
+    return new GenericGFPoly(field, sumDiff);
+  }
+
+  GenericGFPoly multiply(GenericGFPoly other) {
+    if (!field.equals(other.field)) {
+      throw new IllegalArgumentException("GenericGFPolys do not have same GenericGF field");
+    }
+    if (isZero() || other.isZero()) {
+      return field.getZero();
+    }
+    int[] aCoefficients = this.coefficients;
+    int aLength = aCoefficients.length;
+    int[] bCoefficients = other.coefficients;
+    int bLength = bCoefficients.length;
+    int[] product = new int[aLength + bLength - 1];
+    for (int i = 0; i < aLength; i++) {
+      int aCoeff = aCoefficients[i];
+      for (int j = 0; j < bLength; j++) {
+        product[i + j] = GenericGF.addOrSubtract(product[i + j],
+            field.multiply(aCoeff, bCoefficients[j]));
+      }
+    }
+    return new GenericGFPoly(field, product);
+  }
+
+  GenericGFPoly multiply(int scalar) {
+    if (scalar == 0) {
+      return field.getZero();
+    }
+    if (scalar == 1) {
+      return this;
+    }
+    int size = coefficients.length;
+    int[] product = new int[size];
+    for (int i = 0; i < size; i++) {
+      product[i] = field.multiply(coefficients[i], scalar);
+    }
+    return new GenericGFPoly(field, product);
+  }
+
+  GenericGFPoly multiplyByMonomial(int degree, int coefficient) {
+    if (degree < 0) {
+      throw new IllegalArgumentException();
+    }
+    if (coefficient == 0) {
+      return field.getZero();
+    }
+    int size = coefficients.length;
+    int[] product = new int[size + degree];
+    for (int i = 0; i < size; i++) {
+      product[i] = field.multiply(coefficients[i], coefficient);
+    }
+    return new GenericGFPoly(field, product);
+  }
+
+  GenericGFPoly[] divide(GenericGFPoly other) {
+    if (!field.equals(other.field)) {
+      throw new IllegalArgumentException("GenericGFPolys do not have same GenericGF field");
+    }
+    if (other.isZero()) {
+      throw new IllegalArgumentException("Divide by 0");
+    }
+
+    GenericGFPoly quotient = field.getZero();
+    GenericGFPoly remainder = this;
+
+    int denominatorLeadingTerm = other.getCoefficient(other.getDegree());
+    int inverseDenominatorLeadingTerm = field.inverse(denominatorLeadingTerm);
+
+    while (remainder.getDegree() >= other.getDegree() && !remainder.isZero()) {
+      int degreeDifference = remainder.getDegree() - other.getDegree();
+      int scale = field.multiply(remainder.getCoefficient(remainder.getDegree()), inverseDenominatorLeadingTerm);
+      GenericGFPoly term = other.multiplyByMonomial(degreeDifference, scale);
+      GenericGFPoly iterationQuotient = field.buildMonomial(degreeDifference, scale);
+      quotient = quotient.addOrSubtract(iterationQuotient);
+      remainder = remainder.addOrSubtract(term);
+    }
+
+    return new GenericGFPoly[] { quotient, remainder };
+  }
+
+  public String toString() {
+    StringBuffer result = new StringBuffer(8 * getDegree());
+    for (int degree = getDegree(); degree >= 0; degree--) {
+      int coefficient = getCoefficient(degree);
+      if (coefficient != 0) {
+        if (coefficient < 0) {
+          result.append(" - ");
+          coefficient = -coefficient;
+        } else {
+          if (result.length() > 0) {
+            result.append(" + ");
+          }
+        }
+        if (degree == 0 || coefficient != 1) {
+          int alphaPower = field.log(coefficient);
+          if (alphaPower == 0) {
+            result.append('1');
+          } else if (alphaPower == 1) {
+            result.append('a');
+          } else {
+            result.append("a^");
+            result.append(alphaPower);
+          }
+        }
+        if (degree != 0) {
+          if (degree == 1) {
+            result.append('x');
+          } else {
+            result.append("x^");
+            result.append(degree);
+          }
+        }
+      }
+    }
+    return result.toString();
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/reedsolomon/ReedSolomonDecoder.java

@@ -0,0 +1,194 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common.reedsolomon;
+
+/**
+ * <p>Implements Reed-Solomon decoding, as the name implies.</p>
+ *
+ * <p>The algorithm will not be explained here, but the following references were helpful
+ * in creating this implementation:</p>
+ *
+ * <ul>
+ * <li>Bruce Maggs.
+ * <a href="http://www.cs.cmu.edu/afs/cs.cmu.edu/project/pscico-guyb/realworld/www/rs_decode.ps">
+ * "Decoding Reed-Solomon Codes"</a> (see discussion of Forney's Formula)</li>
+ * <li>J.I. Hall. <a href="www.mth.msu.edu/~jhall/classes/codenotes/GRS.pdf">
+ * "Chapter 5. Generalized Reed-Solomon Codes"</a>
+ * (see discussion of Euclidean algorithm)</li>
+ * </ul>
+ *
+ * <p>Much credit is due to William Rucklidge since portions of this code are an indirect
+ * port of his C++ Reed-Solomon implementation.</p>
+ *
+ * @author Sean Owen
+ * @author William Rucklidge
+ * @author sanfordsquires
+ */
+public final class ReedSolomonDecoder {
+
+  private final GenericGF field;
+
+  public ReedSolomonDecoder(GenericGF field) {
+    this.field = field;
+  }
+
+  /**
+   * <p>Decodes given set of received codewords, which include both data and error-correction
+   * codewords. Really, this means it uses Reed-Solomon to detect and correct errors, in-place,
+   * in the input.</p>
+   *
+   * @param received data and error-correction codewords
+   * @param twoS number of error-correction codewords available
+   * @throws ReedSolomonException if decoding fails for any reason
+   */
+  public void decode(int[] received, int twoS) throws ReedSolomonException {
+    GenericGFPoly poly = new GenericGFPoly(field, received);
+    int[] syndromeCoefficients = new int[twoS];
+    boolean dataMatrix = field.equals(GenericGF.DATA_MATRIX_FIELD_256);
+    boolean noError = true;
+    for (int i = 0; i < twoS; i++) {
+      // Thanks to sanfordsquires for this fix:
+      int eval = poly.evaluateAt(field.exp(dataMatrix ? i + 1 : i));
+      syndromeCoefficients[syndromeCoefficients.length - 1 - i] = eval;
+      if (eval != 0) {
+        noError = false;
+      }
+    }
+    if (noError) {
+      return;
+    }
+    GenericGFPoly syndrome = new GenericGFPoly(field, syndromeCoefficients);
+    GenericGFPoly[] sigmaOmega =
+        runEuclideanAlgorithm(field.buildMonomial(twoS, 1), syndrome, twoS);
+    GenericGFPoly sigma = sigmaOmega[0];
+    GenericGFPoly omega = sigmaOmega[1];
+    int[] errorLocations = findErrorLocations(sigma);
+    int[] errorMagnitudes = findErrorMagnitudes(omega, errorLocations, dataMatrix);
+    for (int i = 0; i < errorLocations.length; i++) {
+      int position = received.length - 1 - field.log(errorLocations[i]);
+      if (position < 0) {
+        throw new ReedSolomonException("Bad error location");
+      }
+      received[position] = GenericGF.addOrSubtract(received[position], errorMagnitudes[i]);
+    }
+  }
+
+  private GenericGFPoly[] runEuclideanAlgorithm(GenericGFPoly a, GenericGFPoly b, int R)
+      throws ReedSolomonException {
+    // Assume a's degree is >= b's
+    if (a.getDegree() < b.getDegree()) {
+      GenericGFPoly temp = a;
+      a = b;
+      b = temp;
+    }
+
+    GenericGFPoly rLast = a;
+    GenericGFPoly r = b;
+    GenericGFPoly sLast = field.getOne();
+    GenericGFPoly s = field.getZero();
+    GenericGFPoly tLast = field.getZero();
+    GenericGFPoly t = field.getOne();
+
+    // Run Euclidean algorithm until r's degree is less than R/2
+    while (r.getDegree() >= R / 2) {
+      GenericGFPoly rLastLast = rLast;
+      GenericGFPoly sLastLast = sLast;
+      GenericGFPoly tLastLast = tLast;
+      rLast = r;
+      sLast = s;
+      tLast = t;
+
+      // Divide rLastLast by rLast, with quotient in q and remainder in r
+      if (rLast.isZero()) {
+        // Oops, Euclidean algorithm already terminated?
+        throw new ReedSolomonException("r_{i-1} was zero");
+      }
+      r = rLastLast;
+      GenericGFPoly q = field.getZero();
+      int denominatorLeadingTerm = rLast.getCoefficient(rLast.getDegree());
+      int dltInverse = field.inverse(denominatorLeadingTerm);
+      while (r.getDegree() >= rLast.getDegree() && !r.isZero()) {
+        int degreeDiff = r.getDegree() - rLast.getDegree();
+        int scale = field.multiply(r.getCoefficient(r.getDegree()), dltInverse);
+        q = q.addOrSubtract(field.buildMonomial(degreeDiff, scale));
+        r = r.addOrSubtract(rLast.multiplyByMonomial(degreeDiff, scale));
+      }
+
+      s = q.multiply(sLast).addOrSubtract(sLastLast);
+      t = q.multiply(tLast).addOrSubtract(tLastLast);
+    }
+
+    int sigmaTildeAtZero = t.getCoefficient(0);
+    if (sigmaTildeAtZero == 0) {
+      throw new ReedSolomonException("sigmaTilde(0) was zero");
+    }
+
+    int inverse = field.inverse(sigmaTildeAtZero);
+    GenericGFPoly sigma = t.multiply(inverse);
+    GenericGFPoly omega = r.multiply(inverse);
+    return new GenericGFPoly[]{sigma, omega};
+  }
+
+  private int[] findErrorLocations(GenericGFPoly errorLocator) throws ReedSolomonException {
+    // This is a direct application of Chien's search
+    int numErrors = errorLocator.getDegree();
+    if (numErrors == 1) { // shortcut
+      return new int[] { errorLocator.getCoefficient(1) };
+    }
+    int[] result = new int[numErrors];
+    int e = 0;
+    for (int i = 1; i < field.getSize() && e < numErrors; i++) {
+      if (errorLocator.evaluateAt(i) == 0) {
+        result[e] = field.inverse(i);
+        e++;
+      }
+    }
+    if (e != numErrors) {
+      throw new ReedSolomonException("Error locator degree does not match number of roots");
+    }
+    return result;
+  }
+
+  private int[] findErrorMagnitudes(GenericGFPoly errorEvaluator, int[] errorLocations, boolean dataMatrix) {
+    // This is directly applying Forney's Formula
+    int s = errorLocations.length;
+    int[] result = new int[s];
+    for (int i = 0; i < s; i++) {
+      int xiInverse = field.inverse(errorLocations[i]);
+      int denominator = 1;
+      for (int j = 0; j < s; j++) {
+        if (i != j) {
+          //denominator = field.multiply(denominator,
+          //    GenericGF.addOrSubtract(1, field.multiply(errorLocations[j], xiInverse)));
+          // Above should work but fails on some Apple and Linux JDKs due to a Hotspot bug.
+          // Below is a funny-looking workaround from Steven Parkes
+          int term = field.multiply(errorLocations[j], xiInverse);
+          int termPlus1 = (term & 0x1) == 0 ? term | 1 : term & ~1;
+          denominator = field.multiply(denominator, termPlus1);
+        }
+      }
+      result[i] = field.multiply(errorEvaluator.evaluateAt(xiInverse),
+          field.inverse(denominator));
+      // Thanks to sanfordsquires for this fix:
+      if (dataMatrix) {
+        result[i] = field.multiply(result[i], xiInverse);
+      }
+    }
+    return result;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/reedsolomon/ReedSolomonEncoder.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common.reedsolomon;
+
+import java.util.Vector;
+
+/**
+ * <p>Implements Reed-Solomon enbcoding, as the name implies.</p>
+ *
+ * @author Sean Owen
+ * @author William Rucklidge
+ */
+public final class ReedSolomonEncoder {
+
+  private final GenericGF field;
+  private final Vector cachedGenerators;
+
+  public ReedSolomonEncoder(GenericGF field) {
+    if (!GenericGF.QR_CODE_FIELD_256.equals(field)) {
+      throw new IllegalArgumentException("Only QR Code is supported at this time");
+    }
+    this.field = field;
+    this.cachedGenerators = new Vector();
+    cachedGenerators.addElement(new GenericGFPoly(field, new int[] { 1 }));
+  }
+
+  private GenericGFPoly buildGenerator(int degree) {
+    if (degree >= cachedGenerators.size()) {
+      GenericGFPoly lastGenerator = (GenericGFPoly) cachedGenerators.elementAt(cachedGenerators.size() - 1);
+      for (int d = cachedGenerators.size(); d <= degree; d++) {
+        GenericGFPoly nextGenerator = lastGenerator.multiply(new GenericGFPoly(field, new int[] { 1, field.exp(d - 1) }));
+        cachedGenerators.addElement(nextGenerator);
+        lastGenerator = nextGenerator;
+      }
+    }
+    return (GenericGFPoly) cachedGenerators.elementAt(degree);    
+  }
+
+  public void encode(int[] toEncode, int ecBytes) {
+    if (ecBytes == 0) {
+      throw new IllegalArgumentException("No error correction bytes");
+    }
+    int dataBytes = toEncode.length - ecBytes;
+    if (dataBytes <= 0) {
+      throw new IllegalArgumentException("No data bytes provided");
+    }
+    GenericGFPoly generator = buildGenerator(ecBytes);
+    int[] infoCoefficients = new int[dataBytes];
+    System.arraycopy(toEncode, 0, infoCoefficients, 0, dataBytes);
+    GenericGFPoly info = new GenericGFPoly(field, infoCoefficients);
+    info = info.multiplyByMonomial(ecBytes, 1);
+    GenericGFPoly remainder = info.divide(generator)[1];
+    int[] coefficients = remainder.getCoefficients();
+    int numZeroCoefficients = ecBytes - coefficients.length;
+    for (int i = 0; i < numZeroCoefficients; i++) {
+      toEncode[dataBytes + i] = 0;
+    }
+    System.arraycopy(coefficients, 0, toEncode, dataBytes + numZeroCoefficients, coefficients.length);
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/common/reedsolomon/ReedSolomonException.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common.reedsolomon;
+
+/**
+ * <p>Thrown when an exception occurs during Reed-Solomon decoding, such as when
+ * there are too many errors to correct.</p>
+ *
+ * @author Sean Owen
+ */
+public final class ReedSolomonException extends Exception {
+
+  public ReedSolomonException(String message) {
+    super(message);
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/multi/ByQuadrantReader.java

@@ -0,0 +1,96 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.multi;
+
+import com.google.zxing.BinaryBitmap;
+import com.google.zxing.ChecksumException;
+import com.google.zxing.FormatException;
+import com.google.zxing.NotFoundException;
+import com.google.zxing.Reader;
+import com.google.zxing.Result;
+
+import java.util.Hashtable;
+
+/**
+ * This class attempts to decode a barcode from an image, not by scanning the whole image,
+ * but by scanning subsets of the image. This is important when there may be multiple barcodes in
+ * an image, and detecting a barcode may find parts of multiple barcode and fail to decode
+ * (e.g. QR Codes). Instead this scans the four quadrants of the image -- and also the center
+ * 'quadrant' to cover the case where a barcode is found in the center.
+ *
+ * @see GenericMultipleBarcodeReader
+ */
+public final class ByQuadrantReader implements Reader {
+
+  private final Reader delegate;
+
+  public ByQuadrantReader(Reader delegate) {
+    this.delegate = delegate;
+  }
+
+  public Result decode(BinaryBitmap image)
+      throws NotFoundException, ChecksumException, FormatException {
+    return decode(image, null);
+  }
+
+  public Result decode(BinaryBitmap image, Hashtable hints)
+      throws NotFoundException, ChecksumException, FormatException {
+
+    int width = image.getWidth();
+    int height = image.getHeight();
+    int halfWidth = width / 2;
+    int halfHeight = height / 2;
+
+    BinaryBitmap topLeft = image.crop(0, 0, halfWidth, halfHeight);
+    try {
+      return delegate.decode(topLeft, hints);
+    } catch (NotFoundException re) {
+      // continue
+    }
+
+    BinaryBitmap topRight = image.crop(halfWidth, 0, halfWidth, halfHeight);
+    try {
+      return delegate.decode(topRight, hints);
+    } catch (NotFoundException re) {
+      // continue
+    }
+
+    BinaryBitmap bottomLeft = image.crop(0, halfHeight, halfWidth, halfHeight);
+    try {
+      return delegate.decode(bottomLeft, hints);
+    } catch (NotFoundException re) {
+      // continue
+    }
+
+    BinaryBitmap bottomRight = image.crop(halfWidth, halfHeight, halfWidth, halfHeight);
+    try {
+      return delegate.decode(bottomRight, hints);
+    } catch (NotFoundException re) {
+      // continue
+    }
+
+    int quarterWidth = halfWidth / 2;
+    int quarterHeight = halfHeight / 2;
+    BinaryBitmap center = image.crop(quarterWidth, quarterHeight, halfWidth, halfHeight);
+    return delegate.decode(center, hints);
+  }
+
+  public void reset() {
+    delegate.reset();
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/multi/GenericMultipleBarcodeReader.java

@@ -0,0 +1,156 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.multi;
+
+import com.google.zxing.BinaryBitmap;
+import com.google.zxing.NotFoundException;
+import com.google.zxing.Reader;
+import com.google.zxing.ReaderException;
+import com.google.zxing.Result;
+import com.google.zxing.ResultPoint;
+
+import java.util.Hashtable;
+import java.util.Vector;
+
+/**
+ * <p>Attempts to locate multiple barcodes in an image by repeatedly decoding portion of the image.
+ * After one barcode is found, the areas left, above, right and below the barcode's
+ * {@link com.google.zxing.ResultPoint}s are scanned, recursively.</p>
+ *
+ * <p>A caller may want to also employ {@link ByQuadrantReader} when attempting to find multiple
+ * 2D barcodes, like QR Codes, in an image, where the presence of multiple barcodes might prevent
+ * detecting any one of them.</p>
+ *
+ * <p>That is, instead of passing a {@link Reader} a caller might pass
+ * <code>new ByQuadrantReader(reader)</code>.</p>
+ *
+ * @author Sean Owen
+ */
+public final class GenericMultipleBarcodeReader implements MultipleBarcodeReader {
+
+  private static final int MIN_DIMENSION_TO_RECUR = 100;
+
+  private final Reader delegate;
+
+  public GenericMultipleBarcodeReader(Reader delegate) {
+    this.delegate = delegate;
+  }
+
+  public Result[] decodeMultiple(BinaryBitmap image) throws NotFoundException {
+    return decodeMultiple(image, null);
+  }
+
+  public Result[] decodeMultiple(BinaryBitmap image, Hashtable hints)
+      throws NotFoundException {
+    Vector results = new Vector();
+    doDecodeMultiple(image, hints, results, 0, 0);
+    if (results.isEmpty()) {
+      throw NotFoundException.getNotFoundInstance();
+    }
+    int numResults = results.size();
+    Result[] resultArray = new Result[numResults];
+    for (int i = 0; i < numResults; i++) {
+      resultArray[i] = (Result) results.elementAt(i);
+    }
+    return resultArray;
+  }
+
+  private void doDecodeMultiple(BinaryBitmap image,
+                                Hashtable hints,
+                                Vector results,
+                                int xOffset,
+                                int yOffset) {
+    Result result;
+    try {
+      result = delegate.decode(image, hints);
+    } catch (ReaderException re) {
+      return;
+    }
+    boolean alreadyFound = false;
+    for (int i = 0; i < results.size(); i++) {
+      Result existingResult = (Result) results.elementAt(i);
+      if (existingResult.getText().equals(result.getText())) {
+        alreadyFound = true;
+        break;
+      }
+    }
+    if (alreadyFound) {
+      return;
+    }
+    results.addElement(translateResultPoints(result, xOffset, yOffset));
+    ResultPoint[] resultPoints = result.getResultPoints();
+    if (resultPoints == null || resultPoints.length == 0) {
+      return;
+    }
+    int width = image.getWidth();
+    int height = image.getHeight();
+    float minX = width;
+    float minY = height;
+    float maxX = 0.0f;
+    float maxY = 0.0f;
+    for (int i = 0; i < resultPoints.length; i++) {
+      ResultPoint point = resultPoints[i];
+      float x = point.getX();
+      float y = point.getY();
+      if (x < minX) {
+        minX = x;
+      }
+      if (y < minY) {
+        minY = y;
+      }
+      if (x > maxX) {
+        maxX = x;
+      }
+      if (y > maxY) {
+        maxY = y;
+      }
+    }
+
+    // Decode left of barcode
+    if (minX > MIN_DIMENSION_TO_RECUR) {
+      doDecodeMultiple(image.crop(0, 0, (int) minX, height),
+                       hints, results, xOffset, yOffset);
+    }
+    // Decode above barcode
+    if (minY > MIN_DIMENSION_TO_RECUR) {
+      doDecodeMultiple(image.crop(0, 0, width, (int) minY),
+                       hints, results, xOffset, yOffset);
+    }
+    // Decode right of barcode
+    if (maxX < width - MIN_DIMENSION_TO_RECUR) {
+      doDecodeMultiple(image.crop((int) maxX, 0, width - (int) maxX, height),
+                       hints, results, xOffset + (int) maxX, yOffset);
+    }
+    // Decode below barcode
+    if (maxY < height - MIN_DIMENSION_TO_RECUR) {
+      doDecodeMultiple(image.crop(0, (int) maxY, width, height - (int) maxY),
+                       hints, results, xOffset, yOffset + (int) maxY);
+    }
+  }
+
+  private static Result translateResultPoints(Result result, int xOffset, int yOffset) {
+    ResultPoint[] oldResultPoints = result.getResultPoints();
+    ResultPoint[] newResultPoints = new ResultPoint[oldResultPoints.length];
+    for (int i = 0; i < oldResultPoints.length; i++) {
+      ResultPoint oldPoint = oldResultPoints[i];
+      newResultPoints[i] = new ResultPoint(oldPoint.getX() + xOffset, oldPoint.getY() + yOffset);
+    }
+    return new Result(result.getText(), result.getRawBytes(), newResultPoints,
+        result.getBarcodeFormat());
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/multi/MultipleBarcodeReader.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.multi;
+
+import com.google.zxing.BinaryBitmap;
+import com.google.zxing.NotFoundException;
+import com.google.zxing.Result;
+
+import java.util.Hashtable;
+
+/**
+ * Implementation of this interface attempt to read several barcodes from one image.
+ *
+ * @see com.google.zxing.Reader
+ * @author Sean Owen
+ */
+public interface MultipleBarcodeReader {
+
+  Result[] decodeMultiple(BinaryBitmap image) throws NotFoundException;
+
+  Result[] decodeMultiple(BinaryBitmap image, Hashtable hints) throws NotFoundException;
+
+}

OpenPGP-Keychain/src/com/google/zxing/multi/qrcode/detector/MultiDetector.java

@@ -0,0 +1,72 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.multi.qrcode.detector;
+
+import com.google.zxing.NotFoundException;
+import com.google.zxing.ReaderException;
+import com.google.zxing.common.BitMatrix;
+import com.google.zxing.common.DetectorResult;
+import com.google.zxing.qrcode.detector.Detector;
+import com.google.zxing.qrcode.detector.FinderPatternInfo;
+
+import java.util.Hashtable;
+import java.util.Vector;
+
+/**
+ * <p>Encapsulates logic that can detect one or more QR Codes in an image, even if the QR Code
+ * is rotated or skewed, or partially obscured.</p>
+ *
+ * @author Sean Owen
+ * @author Hannes Erven
+ */
+public final class MultiDetector extends Detector {
+
+  private static final DetectorResult[] EMPTY_DETECTOR_RESULTS = new DetectorResult[0];
+
+  public MultiDetector(BitMatrix image) {
+    super(image);
+  }
+
+  public DetectorResult[] detectMulti(Hashtable hints) throws NotFoundException {
+    BitMatrix image = getImage();
+    MultiFinderPatternFinder finder = new MultiFinderPatternFinder(image);
+    FinderPatternInfo[] info = finder.findMulti(hints);
+
+    if (info == null || info.length == 0) {
+      throw NotFoundException.getNotFoundInstance();
+    }
+
+    Vector result = new Vector();
+    for (int i = 0; i < info.length; i++) {
+      try {
+        result.addElement(processFinderPatternInfo(info[i]));
+      } catch (ReaderException e) {
+        // ignore
+      }
+    }
+    if (result.isEmpty()) {
+      return EMPTY_DETECTOR_RESULTS;
+    } else {
+      DetectorResult[] resultArray = new DetectorResult[result.size()];
+      for (int i = 0; i < result.size(); i++) {
+        resultArray[i] = (DetectorResult) result.elementAt(i);
+      }
+      return resultArray;
+    }
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/multi/qrcode/detector/MultiFinderPatternFinder.java

@@ -0,0 +1,324 @@
+/*
+ * Copyright 2009 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.multi.qrcode.detector;
+
+import com.google.zxing.DecodeHintType;
+import com.google.zxing.NotFoundException;
+import com.google.zxing.ResultPoint;
+import com.google.zxing.ResultPointCallback;
+import com.google.zxing.common.BitMatrix;
+import com.google.zxing.common.Collections;
+import com.google.zxing.common.Comparator;
+import com.google.zxing.qrcode.detector.FinderPattern;
+import com.google.zxing.qrcode.detector.FinderPatternFinder;
+import com.google.zxing.qrcode.detector.FinderPatternInfo;
+
+import java.util.Hashtable;
+import java.util.Vector;
+
+/**
+ * <p>This class attempts to find finder patterns in a QR Code. Finder patterns are the square
+ * markers at three corners of a QR Code.</p>
+ *
+ * <p>This class is thread-safe but not reentrant. Each thread must allocate its own object.
+ *
+ * <p>In contrast to {@link FinderPatternFinder}, this class will return an array of all possible
+ * QR code locations in the image.</p>
+ *
+ * <p>Use the TRY_HARDER hint to ask for a more thorough detection.</p>
+ *
+ * @author Sean Owen
+ * @author Hannes Erven
+ */
+final class MultiFinderPatternFinder extends FinderPatternFinder {
+
+  private static final FinderPatternInfo[] EMPTY_RESULT_ARRAY = new FinderPatternInfo[0];
+
+  // TODO MIN_MODULE_COUNT and MAX_MODULE_COUNT would be great hints to ask the user for
+  // since it limits the number of regions to decode
+
+  // max. legal count of modules per QR code edge (177)
+  private static final float MAX_MODULE_COUNT_PER_EDGE = 180;
+  // min. legal count per modules per QR code edge (11)
+  private static final float MIN_MODULE_COUNT_PER_EDGE = 9;
+
+  /**
+   * More or less arbitrary cutoff point for determining if two finder patterns might belong
+   * to the same code if they differ less than DIFF_MODSIZE_CUTOFF_PERCENT percent in their
+   * estimated modules sizes.
+   */
+  private static final float DIFF_MODSIZE_CUTOFF_PERCENT = 0.05f;
+
+  /**
+   * More or less arbitrary cutoff point for determining if two finder patterns might belong
+   * to the same code if they differ less than DIFF_MODSIZE_CUTOFF pixels/module in their
+   * estimated modules sizes.
+   */
+  private static final float DIFF_MODSIZE_CUTOFF = 0.5f;
+
+
+  /**
+   * A comparator that orders FinderPatterns by their estimated module size.
+   */
+  private static class ModuleSizeComparator implements Comparator {
+    public int compare(Object center1, Object center2) {
+      float value = ((FinderPattern) center2).getEstimatedModuleSize() -
+                    ((FinderPattern) center1).getEstimatedModuleSize();
+      return value < 0.0 ? -1 : value > 0.0 ? 1 : 0;
+    }
+  }
+
+  /**
+   * <p>Creates a finder that will search the image for three finder patterns.</p>
+   *
+   * @param image image to search
+   */
+  MultiFinderPatternFinder(BitMatrix image) {
+    super(image);
+  }
+
+  MultiFinderPatternFinder(BitMatrix image, ResultPointCallback resultPointCallback) {
+    super(image, resultPointCallback);
+  }
+
+  /**
+   * @return the 3 best {@link FinderPattern}s from our list of candidates. The "best" are
+   *         those that have been detected at least {@link #CENTER_QUORUM} times, and whose module
+   *         size differs from the average among those patterns the least
+   * @throws NotFoundException if 3 such finder patterns do not exist
+   */
+  private FinderPattern[][] selectBestPatterns() throws NotFoundException {
+    Vector possibleCenters = getPossibleCenters();
+    int size = possibleCenters.size();
+
+    if (size < 3) {
+      // Couldn't find enough finder patterns
+      throw NotFoundException.getNotFoundInstance();
+    }
+
+    /*
+     * Begin HE modifications to safely detect multiple codes of equal size
+     */
+    if (size == 3) {
+      return new FinderPattern[][]{
+          new FinderPattern[]{
+              (FinderPattern) possibleCenters.elementAt(0),
+              (FinderPattern) possibleCenters.elementAt(1),
+              (FinderPattern) possibleCenters.elementAt(2)
+          }
+      };
+    }
+
+    // Sort by estimated module size to speed up the upcoming checks
+    Collections.insertionSort(possibleCenters, new ModuleSizeComparator());
+
+    /*
+     * Now lets start: build a list of tuples of three finder locations that
+     *  - feature similar module sizes
+     *  - are placed in a distance so the estimated module count is within the QR specification
+     *  - have similar distance between upper left/right and left top/bottom finder patterns
+     *  - form a triangle with 90° angle (checked by comparing top right/bottom left distance
+     *    with pythagoras)
+     *
+     * Note: we allow each point to be used for more than one code region: this might seem
+     * counterintuitive at first, but the performance penalty is not that big. At this point,
+     * we cannot make a good quality decision whether the three finders actually represent
+     * a QR code, or are just by chance layouted so it looks like there might be a QR code there.
+     * So, if the layout seems right, lets have the decoder try to decode.     
+     */
+
+    Vector results = new Vector(); // holder for the results
+
+    for (int i1 = 0; i1 < (size - 2); i1++) {
+      FinderPattern p1 = (FinderPattern) possibleCenters.elementAt(i1);
+      if (p1 == null) {
+        continue;
+      }
+
+      for (int i2 = i1 + 1; i2 < (size - 1); i2++) {
+        FinderPattern p2 = (FinderPattern) possibleCenters.elementAt(i2);
+        if (p2 == null) {
+          continue;
+        }
+
+        // Compare the expected module sizes; if they are really off, skip
+        float vModSize12 = (p1.getEstimatedModuleSize() - p2.getEstimatedModuleSize()) /
+            Math.min(p1.getEstimatedModuleSize(), p2.getEstimatedModuleSize());
+        float vModSize12A = Math.abs(p1.getEstimatedModuleSize() - p2.getEstimatedModuleSize());
+        if (vModSize12A > DIFF_MODSIZE_CUTOFF && vModSize12 >= DIFF_MODSIZE_CUTOFF_PERCENT) {
+          // break, since elements are ordered by the module size deviation there cannot be
+          // any more interesting elements for the given p1.
+          break;
+        }
+
+        for (int i3 = i2 + 1; i3 < size; i3++) {
+          FinderPattern p3 = (FinderPattern) possibleCenters.elementAt(i3);
+          if (p3 == null) {
+            continue;
+          }
+
+          // Compare the expected module sizes; if they are really off, skip
+          float vModSize23 = (p2.getEstimatedModuleSize() - p3.getEstimatedModuleSize()) /
+              Math.min(p2.getEstimatedModuleSize(), p3.getEstimatedModuleSize());
+          float vModSize23A = Math.abs(p2.getEstimatedModuleSize() - p3.getEstimatedModuleSize());
+          if (vModSize23A > DIFF_MODSIZE_CUTOFF && vModSize23 >= DIFF_MODSIZE_CUTOFF_PERCENT) {
+            // break, since elements are ordered by the module size deviation there cannot be
+            // any more interesting elements for the given p1.
+            break;
+          }
+
+          FinderPattern[] test = {p1, p2, p3};
+          ResultPoint.orderBestPatterns(test);
+
+          // Calculate the distances: a = topleft-bottomleft, b=topleft-topright, c = diagonal
+          FinderPatternInfo info = new FinderPatternInfo(test);
+          float dA = ResultPoint.distance(info.getTopLeft(), info.getBottomLeft());
+          float dC = ResultPoint.distance(info.getTopRight(), info.getBottomLeft());
+          float dB = ResultPoint.distance(info.getTopLeft(), info.getTopRight());
+
+          // Check the sizes
+          float estimatedModuleCount = (dA + dB) / (p1.getEstimatedModuleSize() * 2.0f);
+          if (estimatedModuleCount > MAX_MODULE_COUNT_PER_EDGE ||
+              estimatedModuleCount < MIN_MODULE_COUNT_PER_EDGE) {
+            continue;
+          }
+
+          // Calculate the difference of the edge lengths in percent
+          float vABBC = Math.abs((dA - dB) / Math.min(dA, dB));
+          if (vABBC >= 0.1f) {
+            continue;
+          }
+
+          // Calculate the diagonal length by assuming a 90° angle at topleft
+          float dCpy = (float) Math.sqrt(dA * dA + dB * dB);
+          // Compare to the real distance in %
+          float vPyC = Math.abs((dC - dCpy) / Math.min(dC, dCpy));
+
+          if (vPyC >= 0.1f) {
+            continue;
+          }
+
+          // All tests passed!
+          results.addElement(test);
+        } // end iterate p3
+      } // end iterate p2
+    } // end iterate p1
+
+    if (!results.isEmpty()) {
+      FinderPattern[][] resultArray = new FinderPattern[results.size()][];
+      for (int i = 0; i < results.size(); i++) {
+        resultArray[i] = (FinderPattern[]) results.elementAt(i);
+      }
+      return resultArray;
+    }
+
+    // Nothing found!
+    throw NotFoundException.getNotFoundInstance();
+  }
+
+  public FinderPatternInfo[] findMulti(Hashtable hints) throws NotFoundException {
+    boolean tryHarder = hints != null && hints.containsKey(DecodeHintType.TRY_HARDER);
+    BitMatrix image = getImage();
+    int maxI = image.getHeight();
+    int maxJ = image.getWidth();
+    // We are looking for black/white/black/white/black modules in
+    // 1:1:3:1:1 ratio; this tracks the number of such modules seen so far
+
+    // Let's assume that the maximum version QR Code we support takes up 1/4 the height of the
+    // image, and then account for the center being 3 modules in size. This gives the smallest
+    // number of pixels the center could be, so skip this often. When trying harder, look for all
+    // QR versions regardless of how dense they are.
+    int iSkip = (int) (maxI / (MAX_MODULES * 4.0f) * 3);
+    if (iSkip < MIN_SKIP || tryHarder) {
+      iSkip = MIN_SKIP;
+    }
+
+    int[] stateCount = new int[5];
+    for (int i = iSkip - 1; i < maxI; i += iSkip) {
+      // Get a row of black/white values
+      stateCount[0] = 0;
+      stateCount[1] = 0;
+      stateCount[2] = 0;
+      stateCount[3] = 0;
+      stateCount[4] = 0;
+      int currentState = 0;
+      for (int j = 0; j < maxJ; j++) {
+        if (image.get(j, i)) {
+          // Black pixel
+          if ((currentState & 1) == 1) { // Counting white pixels
+            currentState++;
+          }
+          stateCount[currentState]++;
+        } else { // White pixel
+          if ((currentState & 1) == 0) { // Counting black pixels
+            if (currentState == 4) { // A winner?
+              if (foundPatternCross(stateCount)) { // Yes
+                boolean confirmed = handlePossibleCenter(stateCount, i, j);
+                if (!confirmed) {
+                  do { // Advance to next black pixel
+                    j++;
+                  } while (j < maxJ && !image.get(j, i));
+                  j--; // back up to that last white pixel
+                }
+                // Clear state to start looking again
+                currentState = 0;
+                stateCount[0] = 0;
+                stateCount[1] = 0;
+                stateCount[2] = 0;
+                stateCount[3] = 0;
+                stateCount[4] = 0;
+              } else { // No, shift counts back by two
+                stateCount[0] = stateCount[2];
+                stateCount[1] = stateCount[3];
+                stateCount[2] = stateCount[4];
+                stateCount[3] = 1;
+                stateCount[4] = 0;
+                currentState = 3;
+              }
+            } else {
+              stateCount[++currentState]++;
+            }
+          } else { // Counting white pixels
+            stateCount[currentState]++;
+          }
+        }
+      } // for j=...
+
+      if (foundPatternCross(stateCount)) {
+        handlePossibleCenter(stateCount, i, maxJ);
+      } // end if foundPatternCross
+    } // for i=iSkip-1 ...
+    FinderPattern[][] patternInfo = selectBestPatterns();
+    Vector result = new Vector();
+    for (int i = 0; i < patternInfo.length; i++) {
+      FinderPattern[] pattern = patternInfo[i];
+      ResultPoint.orderBestPatterns(pattern);
+      result.addElement(new FinderPatternInfo(pattern));
+    }
+
+    if (result.isEmpty()) {
+      return EMPTY_RESULT_ARRAY;
+    } else {
+      FinderPatternInfo[] resultArray = new FinderPatternInfo[result.size()];
+      for (int i = 0; i < result.size(); i++) {
+        resultArray[i] = (FinderPatternInfo) result.elementAt(i);
+      }
+      return resultArray;
+    }
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/QRCodeWriter.java

@@ -0,0 +1,108 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode;
+
+import com.google.zxing.BarcodeFormat;
+import com.google.zxing.EncodeHintType;
+import com.google.zxing.Writer;
+import com.google.zxing.WriterException;
+import com.google.zxing.common.BitMatrix;
+import com.google.zxing.qrcode.encoder.ByteMatrix;
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+import com.google.zxing.qrcode.encoder.Encoder;
+import com.google.zxing.qrcode.encoder.QRCode;
+
+import java.util.Hashtable;
+
+/**
+ * This object renders a QR Code as a BitMatrix 2D array of greyscale values.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public final class QRCodeWriter implements Writer {
+
+  private static final int QUIET_ZONE_SIZE = 0; // patched for Bitcoin Wallet
+
+  public BitMatrix encode(String contents, BarcodeFormat format, int width, int height)
+      throws WriterException {
+
+    return encode(contents, format, width, height, null);
+  }
+
+  public BitMatrix encode(String contents, BarcodeFormat format, int width, int height,
+      Hashtable hints) throws WriterException {
+
+    if (contents == null || contents.length() == 0) {
+      throw new IllegalArgumentException("Found empty contents");
+    }
+
+    if (format != BarcodeFormat.QR_CODE) {
+      throw new IllegalArgumentException("Can only encode QR_CODE, but got " + format);
+    }
+
+    if (width < 0 || height < 0) {
+      throw new IllegalArgumentException("Requested dimensions are too small: " + width + 'x' +
+          height);
+    }
+
+    ErrorCorrectionLevel errorCorrectionLevel = ErrorCorrectionLevel.L;
+    if (hints != null) {
+      ErrorCorrectionLevel requestedECLevel = (ErrorCorrectionLevel) hints.get(EncodeHintType.ERROR_CORRECTION);
+      if (requestedECLevel != null) {
+        errorCorrectionLevel = requestedECLevel;
+      }
+    }
+
+    QRCode code = new QRCode();
+    Encoder.encode(contents, errorCorrectionLevel, hints, code);
+    return renderResult(code, width, height);
+  }
+
+  // Note that the input matrix uses 0 == white, 1 == black, while the output matrix uses
+  // 0 == black, 255 == white (i.e. an 8 bit greyscale bitmap).
+  private static BitMatrix renderResult(QRCode code, int width, int height) {
+    ByteMatrix input = code.getMatrix();
+    int inputWidth = input.getWidth();
+    int inputHeight = input.getHeight();
+    int qrWidth = inputWidth + (QUIET_ZONE_SIZE << 1);
+    int qrHeight = inputHeight + (QUIET_ZONE_SIZE << 1);
+    int outputWidth = Math.max(width, qrWidth);
+    int outputHeight = Math.max(height, qrHeight);
+
+    int multiple = Math.min(outputWidth / qrWidth, outputHeight / qrHeight);
+    // Padding includes both the quiet zone and the extra white pixels to accommodate the requested
+    // dimensions. For example, if input is 25x25 the QR will be 33x33 including the quiet zone.
+    // If the requested size is 200x160, the multiple will be 4, for a QR of 132x132. These will
+    // handle all the padding from 100x100 (the actual QR) up to 200x160.
+    int leftPadding = (outputWidth - (inputWidth * multiple)) / 2;
+    int topPadding = (outputHeight - (inputHeight * multiple)) / 2;
+
+    BitMatrix output = new BitMatrix(outputWidth, outputHeight);
+
+    for (int inputY = 0, outputY = topPadding; inputY < inputHeight; inputY++, outputY += multiple) {
+      // Write the contents of this row of the barcode
+      for (int inputX = 0, outputX = leftPadding; inputX < inputWidth; inputX++, outputX += multiple) {
+        if (input.get(inputX, inputY) == 1) {
+          output.setRegion(outputX, outputY, multiple, multiple);
+        }
+      }
+    }
+
+    return output;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/BitMatrixParser.java

@@ -0,0 +1,203 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.decoder;
+
+import com.google.zxing.FormatException;
+import com.google.zxing.common.BitMatrix;
+
+/**
+ * @author Sean Owen
+ */
+final class BitMatrixParser {
+
+  private final BitMatrix bitMatrix;
+  private Version parsedVersion;
+  private FormatInformation parsedFormatInfo;
+
+  /**
+   * @param bitMatrix {@link BitMatrix} to parse
+   * @throws FormatException if dimension is not >= 21 and 1 mod 4
+   */
+  BitMatrixParser(BitMatrix bitMatrix) throws FormatException {
+    int dimension = bitMatrix.getHeight();
+    if (dimension < 21 || (dimension & 0x03) != 1) {
+      throw FormatException.getFormatInstance();
+    }
+    this.bitMatrix = bitMatrix;
+  }
+
+  /**
+   * <p>Reads format information from one of its two locations within the QR Code.</p>
+   *
+   * @return {@link FormatInformation} encapsulating the QR Code's format info
+   * @throws FormatException if both format information locations cannot be parsed as
+   * the valid encoding of format information
+   */
+  FormatInformation readFormatInformation() throws FormatException {
+
+    if (parsedFormatInfo != null) {
+      return parsedFormatInfo;
+    }
+
+    // Read top-left format info bits
+    int formatInfoBits1 = 0;
+    for (int i = 0; i < 6; i++) {
+      formatInfoBits1 = copyBit(i, 8, formatInfoBits1);
+    }
+    // .. and skip a bit in the timing pattern ...
+    formatInfoBits1 = copyBit(7, 8, formatInfoBits1);
+    formatInfoBits1 = copyBit(8, 8, formatInfoBits1);
+    formatInfoBits1 = copyBit(8, 7, formatInfoBits1);
+    // .. and skip a bit in the timing pattern ...
+    for (int j = 5; j >= 0; j--) {
+      formatInfoBits1 = copyBit(8, j, formatInfoBits1);
+    }
+
+    // Read the top-right/bottom-left pattern too
+    int dimension = bitMatrix.getHeight();
+    int formatInfoBits2 = 0;
+    int jMin = dimension - 7;
+    for (int j = dimension - 1; j >= jMin; j--) {
+      formatInfoBits2 = copyBit(8, j, formatInfoBits2);
+    }
+    for (int i = dimension - 8; i < dimension; i++) {
+      formatInfoBits2 = copyBit(i, 8, formatInfoBits2);
+    }
+
+    parsedFormatInfo = FormatInformation.decodeFormatInformation(formatInfoBits1, formatInfoBits2);
+    if (parsedFormatInfo != null) {
+      return parsedFormatInfo;
+    }
+    throw FormatException.getFormatInstance();
+  }
+
+  /**
+   * <p>Reads version information from one of its two locations within the QR Code.</p>
+   *
+   * @return {@link Version} encapsulating the QR Code's version
+   * @throws FormatException if both version information locations cannot be parsed as
+   * the valid encoding of version information
+   */
+  Version readVersion() throws FormatException {
+
+    if (parsedVersion != null) {
+      return parsedVersion;
+    }
+
+    int dimension = bitMatrix.getHeight();
+
+    int provisionalVersion = (dimension - 17) >> 2;
+    if (provisionalVersion <= 6) {
+      return Version.getVersionForNumber(provisionalVersion);
+    }
+
+    // Read top-right version info: 3 wide by 6 tall
+    int versionBits = 0;
+    int ijMin = dimension - 11;
+    for (int j = 5; j >= 0; j--) {
+      for (int i = dimension - 9; i >= ijMin; i--) {
+        versionBits = copyBit(i, j, versionBits);
+      }
+    }
+
+    parsedVersion = Version.decodeVersionInformation(versionBits);
+    if (parsedVersion != null && parsedVersion.getDimensionForVersion() == dimension) {
+      return parsedVersion;
+    }
+
+    // Hmm, failed. Try bottom left: 6 wide by 3 tall
+    versionBits = 0;
+    for (int i = 5; i >= 0; i--) {
+      for (int j = dimension - 9; j >= ijMin; j--) {
+        versionBits = copyBit(i, j, versionBits);
+      }
+    }
+
+    parsedVersion = Version.decodeVersionInformation(versionBits);
+    if (parsedVersion != null && parsedVersion.getDimensionForVersion() == dimension) {
+      return parsedVersion;
+    }
+    throw FormatException.getFormatInstance();
+  }
+
+  private int copyBit(int i, int j, int versionBits) {
+    return bitMatrix.get(i, j) ? (versionBits << 1) | 0x1 : versionBits << 1;
+  }
+
+  /**
+   * <p>Reads the bits in the {@link BitMatrix} representing the finder pattern in the
+   * correct order in order to reconstitute the codewords bytes contained within the
+   * QR Code.</p>
+   *
+   * @return bytes encoded within the QR Code
+   * @throws FormatException if the exact number of bytes expected is not read
+   */
+  byte[] readCodewords() throws FormatException {
+
+    FormatInformation formatInfo = readFormatInformation();
+    Version version = readVersion();
+
+    // Get the data mask for the format used in this QR Code. This will exclude
+    // some bits from reading as we wind through the bit matrix.
+    DataMask dataMask = DataMask.forReference((int) formatInfo.getDataMask());
+    int dimension = bitMatrix.getHeight();
+    dataMask.unmaskBitMatrix(bitMatrix, dimension);
+
+    BitMatrix functionPattern = version.buildFunctionPattern();
+
+    boolean readingUp = true;
+    byte[] result = new byte[version.getTotalCodewords()];
+    int resultOffset = 0;
+    int currentByte = 0;
+    int bitsRead = 0;
+    // Read columns in pairs, from right to left
+    for (int j = dimension - 1; j > 0; j -= 2) {
+      if (j == 6) {
+        // Skip whole column with vertical alignment pattern;
+        // saves time and makes the other code proceed more cleanly
+        j--;
+      }
+      // Read alternatingly from bottom to top then top to bottom
+      for (int count = 0; count < dimension; count++) {
+        int i = readingUp ? dimension - 1 - count : count;
+        for (int col = 0; col < 2; col++) {
+          // Ignore bits covered by the function pattern
+          if (!functionPattern.get(j - col, i)) {
+            // Read a bit
+            bitsRead++;
+            currentByte <<= 1;
+            if (bitMatrix.get(j - col, i)) {
+              currentByte |= 1;
+            }
+            // If we've made a whole byte, save it off
+            if (bitsRead == 8) {
+              result[resultOffset++] = (byte) currentByte;
+              bitsRead = 0;
+              currentByte = 0;
+            }
+          }
+        }
+      }
+      readingUp ^= true; // readingUp = !readingUp; // switch directions
+    }
+    if (resultOffset != version.getTotalCodewords()) {
+      throw FormatException.getFormatInstance();
+    }
+    return result;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/DataBlock.java

@@ -0,0 +1,123 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.decoder;
+
+/**
+ * <p>Encapsulates a block of data within a QR Code. QR Codes may split their data into
+ * multiple blocks, each of which is a unit of data and error-correction codewords. Each
+ * is represented by an instance of this class.</p>
+ *
+ * @author Sean Owen
+ */
+final class DataBlock {
+
+  private final int numDataCodewords;
+  private final byte[] codewords;
+
+  private DataBlock(int numDataCodewords, byte[] codewords) {
+    this.numDataCodewords = numDataCodewords;
+    this.codewords = codewords;
+  }
+
+  /**
+   * <p>When QR Codes use multiple data blocks, they are actually interleaved.
+   * That is, the first byte of data block 1 to n is written, then the second bytes, and so on. This
+   * method will separate the data into original blocks.</p>
+   *
+   * @param rawCodewords bytes as read directly from the QR Code
+   * @param version version of the QR Code
+   * @param ecLevel error-correction level of the QR Code
+   * @return DataBlocks containing original bytes, "de-interleaved" from representation in the
+   *         QR Code
+   */
+  static DataBlock[] getDataBlocks(byte[] rawCodewords,
+                                   Version version,
+                                   ErrorCorrectionLevel ecLevel) {
+
+    if (rawCodewords.length != version.getTotalCodewords()) {
+      throw new IllegalArgumentException();
+    }
+
+    // Figure out the number and size of data blocks used by this version and
+    // error correction level
+    Version.ECBlocks ecBlocks = version.getECBlocksForLevel(ecLevel);
+
+    // First count the total number of data blocks
+    int totalBlocks = 0;
+    Version.ECB[] ecBlockArray = ecBlocks.getECBlocks();
+    for (int i = 0; i < ecBlockArray.length; i++) {
+      totalBlocks += ecBlockArray[i].getCount();
+    }
+
+    // Now establish DataBlocks of the appropriate size and number of data codewords
+    DataBlock[] result = new DataBlock[totalBlocks];
+    int numResultBlocks = 0;
+    for (int j = 0; j < ecBlockArray.length; j++) {
+      Version.ECB ecBlock = ecBlockArray[j];
+      for (int i = 0; i < ecBlock.getCount(); i++) {
+        int numDataCodewords = ecBlock.getDataCodewords();
+        int numBlockCodewords = ecBlocks.getECCodewordsPerBlock() + numDataCodewords;
+        result[numResultBlocks++] = new DataBlock(numDataCodewords, new byte[numBlockCodewords]);
+      }
+    }
+
+    // All blocks have the same amount of data, except that the last n
+    // (where n may be 0) have 1 more byte. Figure out where these start.
+    int shorterBlocksTotalCodewords = result[0].codewords.length;
+    int longerBlocksStartAt = result.length - 1;
+    while (longerBlocksStartAt >= 0) {
+      int numCodewords = result[longerBlocksStartAt].codewords.length;
+      if (numCodewords == shorterBlocksTotalCodewords) {
+        break;
+      }
+      longerBlocksStartAt--;
+    }
+    longerBlocksStartAt++;
+
+    int shorterBlocksNumDataCodewords = shorterBlocksTotalCodewords - ecBlocks.getECCodewordsPerBlock();
+    // The last elements of result may be 1 element longer;
+    // first fill out as many elements as all of them have
+    int rawCodewordsOffset = 0;
+    for (int i = 0; i < shorterBlocksNumDataCodewords; i++) {
+      for (int j = 0; j < numResultBlocks; j++) {
+        result[j].codewords[i] = rawCodewords[rawCodewordsOffset++];
+      }
+    }
+    // Fill out the last data block in the longer ones
+    for (int j = longerBlocksStartAt; j < numResultBlocks; j++) {
+      result[j].codewords[shorterBlocksNumDataCodewords] = rawCodewords[rawCodewordsOffset++];
+    }
+    // Now add in error correction blocks
+    int max = result[0].codewords.length;
+    for (int i = shorterBlocksNumDataCodewords; i < max; i++) {
+      for (int j = 0; j < numResultBlocks; j++) {
+        int iOffset = j < longerBlocksStartAt ? i : i + 1;
+        result[j].codewords[iOffset] = rawCodewords[rawCodewordsOffset++];
+      }
+    }
+    return result;
+  }
+
+  int getNumDataCodewords() {
+    return numDataCodewords;
+  }
+
+  byte[] getCodewords() {
+    return codewords;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/DataMask.java

@@ -0,0 +1,155 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.decoder;
+
+import com.google.zxing.common.BitMatrix;
+
+/**
+ * <p>Encapsulates data masks for the data bits in a QR code, per ISO 18004:2006 6.8. Implementations
+ * of this class can un-mask a raw BitMatrix. For simplicity, they will unmask the entire BitMatrix,
+ * including areas used for finder patterns, timing patterns, etc. These areas should be unused
+ * after the point they are unmasked anyway.</p>
+ *
+ * <p>Note that the diagram in section 6.8.1 is misleading since it indicates that i is column position
+ * and j is row position. In fact, as the text says, i is row position and j is column position.</p>
+ *
+ * @author Sean Owen
+ */
+abstract class DataMask {
+
+  /**
+   * See ISO 18004:2006 6.8.1
+   */
+  private static final DataMask[] DATA_MASKS = {
+      new DataMask000(),
+      new DataMask001(),
+      new DataMask010(),
+      new DataMask011(),
+      new DataMask100(),
+      new DataMask101(),
+      new DataMask110(),
+      new DataMask111(),
+  };
+
+  private DataMask() {
+  }
+
+  /**
+   * <p>Implementations of this method reverse the data masking process applied to a QR Code and
+   * make its bits ready to read.</p>
+   *
+   * @param bits representation of QR Code bits
+   * @param dimension dimension of QR Code, represented by bits, being unmasked
+   */
+  final void unmaskBitMatrix(BitMatrix bits, int dimension) {
+    for (int i = 0; i < dimension; i++) {
+      for (int j = 0; j < dimension; j++) {
+        if (isMasked(i, j)) {
+          bits.flip(j, i);
+        }
+      }
+    }
+  }
+
+  abstract boolean isMasked(int i, int j);
+
+  /**
+   * @param reference a value between 0 and 7 indicating one of the eight possible
+   * data mask patterns a QR Code may use
+   * @return DataMask encapsulating the data mask pattern
+   */
+  static DataMask forReference(int reference) {
+    if (reference < 0 || reference > 7) {
+      throw new IllegalArgumentException();
+    }
+    return DATA_MASKS[reference];
+  }
+
+  /**
+   * 000: mask bits for which (x + y) mod 2 == 0
+   */
+  private static class DataMask000 extends DataMask {
+    boolean isMasked(int i, int j) {
+      return ((i + j) & 0x01) == 0;
+    }
+  }
+
+  /**
+   * 001: mask bits for which x mod 2 == 0
+   */
+  private static class DataMask001 extends DataMask {
+    boolean isMasked(int i, int j) {
+      return (i & 0x01) == 0;
+    }
+  }
+
+  /**
+   * 010: mask bits for which y mod 3 == 0
+   */
+  private static class DataMask010 extends DataMask {
+    boolean isMasked(int i, int j) {
+      return j % 3 == 0;
+    }
+  }
+
+  /**
+   * 011: mask bits for which (x + y) mod 3 == 0
+   */
+  private static class DataMask011 extends DataMask {
+    boolean isMasked(int i, int j) {
+      return (i + j) % 3 == 0;
+    }
+  }
+
+  /**
+   * 100: mask bits for which (x/2 + y/3) mod 2 == 0
+   */
+  private static class DataMask100 extends DataMask {
+    boolean isMasked(int i, int j) {
+      return (((i >>> 1) + (j /3)) & 0x01) == 0;
+    }
+  }
+
+  /**
+   * 101: mask bits for which xy mod 2 + xy mod 3 == 0
+   */
+  private static class DataMask101 extends DataMask {
+    boolean isMasked(int i, int j) {
+      int temp = i * j;
+      return (temp & 0x01) + (temp % 3) == 0;
+    }
+  }
+
+  /**
+   * 110: mask bits for which (xy mod 2 + xy mod 3) mod 2 == 0
+   */
+  private static class DataMask110 extends DataMask {
+    boolean isMasked(int i, int j) {
+      int temp = i * j;
+      return (((temp & 0x01) + (temp % 3)) & 0x01) == 0;
+    }
+  }
+
+  /**
+   * 111: mask bits for which ((x+y)mod 2 + xy mod 3) mod 2 == 0
+   */
+  private static class DataMask111 extends DataMask {
+    boolean isMasked(int i, int j) {
+      return ((((i + j) & 0x01) + ((i * j) % 3)) & 0x01) == 0;
+    }
+  }
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/DecodedBitStreamParser.java

@@ -0,0 +1,322 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.decoder;
+
+import com.google.zxing.FormatException;
+import com.google.zxing.common.BitSource;
+import com.google.zxing.common.CharacterSetECI;
+import com.google.zxing.common.DecoderResult;
+import com.google.zxing.common.StringUtils;
+
+import java.io.UnsupportedEncodingException;
+import java.util.Hashtable;
+import java.util.Vector;
+
+/**
+ * <p>QR Codes can encode text as bits in one of several modes, and can use multiple modes
+ * in one QR Code. This class decodes the bits back into text.</p>
+ *
+ * <p>See ISO 18004:2006, 6.4.3 - 6.4.7</p>
+ *
+ * @author Sean Owen
+ */
+final class DecodedBitStreamParser {
+
+  /**
+   * See ISO 18004:2006, 6.4.4 Table 5
+   */
+  private static final char[] ALPHANUMERIC_CHARS = {
+      '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B',
+      'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N',
+      'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
+      ' ', '$', '%', '*', '+', '-', '.', '/', ':'
+  };
+  private static final int GB2312_SUBSET = 1;
+
+  private DecodedBitStreamParser() {
+  }
+
+  static DecoderResult decode(byte[] bytes, Version version, ErrorCorrectionLevel ecLevel, Hashtable hints)
+      throws FormatException {
+    BitSource bits = new BitSource(bytes);
+    StringBuffer result = new StringBuffer(50);
+    CharacterSetECI currentCharacterSetECI = null;
+    boolean fc1InEffect = false;
+    Vector byteSegments = new Vector(1);
+    Mode mode;
+    do {
+      // While still another segment to read...
+      if (bits.available() < 4) {
+        // OK, assume we're done. Really, a TERMINATOR mode should have been recorded here
+        mode = Mode.TERMINATOR;
+      } else {
+        try {
+          mode = Mode.forBits(bits.readBits(4)); // mode is encoded by 4 bits
+        } catch (IllegalArgumentException iae) {
+          throw FormatException.getFormatInstance();
+        }
+      }
+      if (!mode.equals(Mode.TERMINATOR)) {
+        if (mode.equals(Mode.FNC1_FIRST_POSITION) || mode.equals(Mode.FNC1_SECOND_POSITION)) {
+          // We do little with FNC1 except alter the parsed result a bit according to the spec
+          fc1InEffect = true;
+        } else if (mode.equals(Mode.STRUCTURED_APPEND)) {
+          // not really supported; all we do is ignore it
+          // Read next 8 bits (symbol sequence #) and 8 bits (parity data), then continue
+          bits.readBits(16);
+        } else if (mode.equals(Mode.ECI)) {
+          // Count doesn't apply to ECI
+          int value = parseECIValue(bits);
+          currentCharacterSetECI = CharacterSetECI.getCharacterSetECIByValue(value);
+          if (currentCharacterSetECI == null) {
+            throw FormatException.getFormatInstance();
+          }
+        } else {
+          // First handle Hanzi mode which does not start with character count
+          if (mode.equals(Mode.HANZI)) {
+        		//chinese mode contains a sub set indicator right after mode indicator
+        		int subset = bits.readBits(4);
+        		int countHanzi = bits.readBits(mode.getCharacterCountBits(version));
+        		if (subset == GB2312_SUBSET) {
+        			decodeHanziSegment(bits, result, countHanzi);
+            }
+          } else {
+            // "Normal" QR code modes:
+            // How many characters will follow, encoded in this mode?
+            int count = bits.readBits(mode.getCharacterCountBits(version));
+            if (mode.equals(Mode.NUMERIC)) {
+              decodeNumericSegment(bits, result, count);
+            } else if (mode.equals(Mode.ALPHANUMERIC)) {
+              decodeAlphanumericSegment(bits, result, count, fc1InEffect);
+            } else if (mode.equals(Mode.BYTE)) {
+              decodeByteSegment(bits, result, count, currentCharacterSetECI, byteSegments, hints);
+            } else if (mode.equals(Mode.KANJI)) {
+              decodeKanjiSegment(bits, result, count);
+            } else {
+              throw FormatException.getFormatInstance();
+            }
+          }
+        }
+      }
+    } while (!mode.equals(Mode.TERMINATOR));
+
+    return new DecoderResult(bytes,
+                             result.toString(),
+                             byteSegments.isEmpty() ? null : byteSegments,
+                             ecLevel == null ? null : ecLevel.toString());
+  }
+
+  /**
+   * See specification GBT 18284-2000
+   */
+  private static void decodeHanziSegment(BitSource bits,
+                                         StringBuffer result,
+                                         int count) throws FormatException {
+    // Don't crash trying to read more bits than we have available.
+    if (count * 13 > bits.available()) {
+      throw FormatException.getFormatInstance();
+    }
+
+    // Each character will require 2 bytes. Read the characters as 2-byte pairs
+    // and decode as GB2312 afterwards
+    byte[] buffer = new byte[2 * count];
+    int offset = 0;
+    while (count > 0) {
+      // Each 13 bits encodes a 2-byte character
+      int twoBytes = bits.readBits(13);
+      int assembledTwoBytes = ((twoBytes / 0x060) << 8) | (twoBytes % 0x060);
+      if (assembledTwoBytes < 0x003BF) {
+        // In the 0xA1A1 to 0xAAFE range
+        assembledTwoBytes += 0x0A1A1;
+      } else {
+        // In the 0xB0A1 to 0xFAFE range
+        assembledTwoBytes += 0x0A6A1;
+      }
+      buffer[offset] = (byte) ((assembledTwoBytes >> 8) & 0xFF);
+      buffer[offset + 1] = (byte) (assembledTwoBytes & 0xFF);
+      offset += 2;
+      count--;
+    }
+
+    try {
+      result.append(new String(buffer, StringUtils.GB2312));
+    } catch (UnsupportedEncodingException uee) {
+      throw FormatException.getFormatInstance();
+    }
+  }
+
+  private static void decodeKanjiSegment(BitSource bits,
+                                         StringBuffer result,
+                                         int count) throws FormatException {
+    // Don't crash trying to read more bits than we have available.
+    if (count * 13 > bits.available()) {
+      throw FormatException.getFormatInstance();
+    }
+
+    // Each character will require 2 bytes. Read the characters as 2-byte pairs
+    // and decode as Shift_JIS afterwards
+    byte[] buffer = new byte[2 * count];
+    int offset = 0;
+    while (count > 0) {
+      // Each 13 bits encodes a 2-byte character
+      int twoBytes = bits.readBits(13);
+      int assembledTwoBytes = ((twoBytes / 0x0C0) << 8) | (twoBytes % 0x0C0);
+      if (assembledTwoBytes < 0x01F00) {
+        // In the 0x8140 to 0x9FFC range
+        assembledTwoBytes += 0x08140;
+      } else {
+        // In the 0xE040 to 0xEBBF range
+        assembledTwoBytes += 0x0C140;
+      }
+      buffer[offset] = (byte) (assembledTwoBytes >> 8);
+      buffer[offset + 1] = (byte) assembledTwoBytes;
+      offset += 2;
+      count--;
+    }
+    // Shift_JIS may not be supported in some environments:
+    try {
+      result.append(new String(buffer, StringUtils.SHIFT_JIS));
+    } catch (UnsupportedEncodingException uee) {
+      throw FormatException.getFormatInstance();
+    }
+  }
+
+  private static void decodeByteSegment(BitSource bits,
+                                        StringBuffer result,
+                                        int count,
+                                        CharacterSetECI currentCharacterSetECI,
+                                        Vector byteSegments,
+                                        Hashtable hints) throws FormatException {
+    // Don't crash trying to read more bits than we have available.
+    if (count << 3 > bits.available()) {
+      throw FormatException.getFormatInstance();
+    }
+
+    byte[] readBytes = new byte[count];
+    for (int i = 0; i < count; i++) {
+      readBytes[i] = (byte) bits.readBits(8);
+    }
+    String encoding;
+    if (currentCharacterSetECI == null) {
+    // The spec isn't clear on this mode; see
+    // section 6.4.5: t does not say which encoding to assuming
+    // upon decoding. I have seen ISO-8859-1 used as well as
+    // Shift_JIS -- without anything like an ECI designator to
+    // give a hint.
+      encoding = StringUtils.guessEncoding(readBytes, hints);
+    } else {
+      encoding = currentCharacterSetECI.getEncodingName();
+    }
+    try {
+      result.append(new String(readBytes, encoding));
+    } catch (UnsupportedEncodingException uce) {
+      throw FormatException.getFormatInstance();
+    }
+    byteSegments.addElement(readBytes);
+  }
+
+  private static char toAlphaNumericChar(int value) throws FormatException {
+    if (value >= ALPHANUMERIC_CHARS.length) {
+      throw FormatException.getFormatInstance();
+    }
+    return ALPHANUMERIC_CHARS[value];
+  }
+
+  private static void decodeAlphanumericSegment(BitSource bits,
+                                                StringBuffer result,
+                                                int count,
+                                                boolean fc1InEffect) throws FormatException {
+    // Read two characters at a time
+    int start = result.length();
+    while (count > 1) {
+      int nextTwoCharsBits = bits.readBits(11);
+      result.append(toAlphaNumericChar(nextTwoCharsBits / 45));
+      result.append(toAlphaNumericChar(nextTwoCharsBits % 45));
+      count -= 2;
+    }
+    if (count == 1) {
+      // special case: one character left
+      result.append(toAlphaNumericChar(bits.readBits(6)));
+    }
+    // See section 6.4.8.1, 6.4.8.2
+    if (fc1InEffect) {
+      // We need to massage the result a bit if in an FNC1 mode:
+      for (int i = start; i < result.length(); i++) {
+        if (result.charAt(i) == '%') {
+          if (i < result.length() - 1 && result.charAt(i + 1) == '%') {
+            // %% is rendered as %
+            result.deleteCharAt(i + 1);
+          } else {
+            // In alpha mode, % should be converted to FNC1 separator 0x1D
+            result.setCharAt(i, (char) 0x1D);
+          }
+        }
+      }
+    }
+  }
+
+  private static void decodeNumericSegment(BitSource bits,
+                                           StringBuffer result,
+                                           int count) throws FormatException {
+    // Read three digits at a time
+    while (count >= 3) {
+      // Each 10 bits encodes three digits
+      int threeDigitsBits = bits.readBits(10);
+      if (threeDigitsBits >= 1000) {
+        throw FormatException.getFormatInstance();
+      }
+      result.append(toAlphaNumericChar(threeDigitsBits / 100));
+      result.append(toAlphaNumericChar((threeDigitsBits / 10) % 10));
+      result.append(toAlphaNumericChar(threeDigitsBits % 10));
+      count -= 3;
+    }
+    if (count == 2) {
+      // Two digits left over to read, encoded in 7 bits
+      int twoDigitsBits = bits.readBits(7);
+      if (twoDigitsBits >= 100) {
+        throw FormatException.getFormatInstance();
+      }
+      result.append(toAlphaNumericChar(twoDigitsBits / 10));
+      result.append(toAlphaNumericChar(twoDigitsBits % 10));
+    } else if (count == 1) {
+      // One digit left over to read
+      int digitBits = bits.readBits(4);
+      if (digitBits >= 10) {
+        throw FormatException.getFormatInstance();
+      }
+      result.append(toAlphaNumericChar(digitBits));
+    }
+  }
+
+  private static int parseECIValue(BitSource bits) {
+    int firstByte = bits.readBits(8);
+    if ((firstByte & 0x80) == 0) {
+      // just one byte
+      return firstByte & 0x7F;
+    } else if ((firstByte & 0xC0) == 0x80) {
+      // two bytes
+      int secondByte = bits.readBits(8);
+      return ((firstByte & 0x3F) << 8) | secondByte;
+    } else if ((firstByte & 0xE0) == 0xC0) {
+      // three bytes
+      int secondThirdBytes = bits.readBits(16);
+      return ((firstByte & 0x1F) << 16) | secondThirdBytes;
+    }
+    throw new IllegalArgumentException("Bad ECI bits starting with byte " + firstByte);
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/ErrorCorrectionLevel.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.decoder;
+
+/**
+ * <p>See ISO 18004:2006, 6.5.1. This enum encapsulates the four error correction levels
+ * defined by the QR code standard.</p>
+ *
+ * @author Sean Owen
+ */
+public final class ErrorCorrectionLevel {
+
+  // No, we can't use an enum here. J2ME doesn't support it.
+
+  /**
+   * L = ~7% correction
+   */
+  public static final ErrorCorrectionLevel L = new ErrorCorrectionLevel(0, 0x01, "L");
+  /**
+   * M = ~15% correction
+   */
+  public static final ErrorCorrectionLevel M = new ErrorCorrectionLevel(1, 0x00, "M");
+  /**
+   * Q = ~25% correction
+   */
+  public static final ErrorCorrectionLevel Q = new ErrorCorrectionLevel(2, 0x03, "Q");
+  /**
+   * H = ~30% correction
+   */
+  public static final ErrorCorrectionLevel H = new ErrorCorrectionLevel(3, 0x02, "H");
+
+  private static final ErrorCorrectionLevel[] FOR_BITS = {M, L, H, Q};
+
+  private final int ordinal;
+  private final int bits;
+  private final String name;
+
+  private ErrorCorrectionLevel(int ordinal, int bits, String name) {
+    this.ordinal = ordinal;
+    this.bits = bits;
+    this.name = name;
+  }
+
+  public int ordinal() {
+    return ordinal;
+  }
+
+  public int getBits() {
+    return bits;
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public String toString() {
+    return name;
+  }
+
+  /**
+   * @param bits int containing the two bits encoding a QR Code's error correction level
+   * @return ErrorCorrectionLevel representing the encoded error correction level
+   */
+  public static ErrorCorrectionLevel forBits(int bits) {
+    if (bits < 0 || bits >= FOR_BITS.length) {
+      throw new IllegalArgumentException();
+    }
+    return FOR_BITS[bits];
+  }
+
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/FormatInformation.java

@@ -0,0 +1,171 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.decoder;
+
+/**
+ * <p>Encapsulates a QR Code's format information, including the data mask used and
+ * error correction level.</p>
+ *
+ * @author Sean Owen
+ * @see DataMask
+ * @see ErrorCorrectionLevel
+ */
+final class FormatInformation {
+
+  private static final int FORMAT_INFO_MASK_QR = 0x5412;
+
+  /**
+   * See ISO 18004:2006, Annex C, Table C.1
+   */
+  private static final int[][] FORMAT_INFO_DECODE_LOOKUP = {
+      {0x5412, 0x00},
+      {0x5125, 0x01},
+      {0x5E7C, 0x02},
+      {0x5B4B, 0x03},
+      {0x45F9, 0x04},
+      {0x40CE, 0x05},
+      {0x4F97, 0x06},
+      {0x4AA0, 0x07},
+      {0x77C4, 0x08},
+      {0x72F3, 0x09},
+      {0x7DAA, 0x0A},
+      {0x789D, 0x0B},
+      {0x662F, 0x0C},
+      {0x6318, 0x0D},
+      {0x6C41, 0x0E},
+      {0x6976, 0x0F},
+      {0x1689, 0x10},
+      {0x13BE, 0x11},
+      {0x1CE7, 0x12},
+      {0x19D0, 0x13},
+      {0x0762, 0x14},
+      {0x0255, 0x15},
+      {0x0D0C, 0x16},
+      {0x083B, 0x17},
+      {0x355F, 0x18},
+      {0x3068, 0x19},
+      {0x3F31, 0x1A},
+      {0x3A06, 0x1B},
+      {0x24B4, 0x1C},
+      {0x2183, 0x1D},
+      {0x2EDA, 0x1E},
+      {0x2BED, 0x1F},
+  };
+
+  /**
+   * Offset i holds the number of 1 bits in the binary representation of i
+   */
+  private static final int[] BITS_SET_IN_HALF_BYTE =
+      {0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4};
+
+  private final ErrorCorrectionLevel errorCorrectionLevel;
+  private final byte dataMask;
+
+  private FormatInformation(int formatInfo) {
+    // Bits 3,4
+    errorCorrectionLevel = ErrorCorrectionLevel.forBits((formatInfo >> 3) & 0x03);
+    // Bottom 3 bits
+    dataMask = (byte) (formatInfo & 0x07);
+  }
+
+  static int numBitsDiffering(int a, int b) {
+    a ^= b; // a now has a 1 bit exactly where its bit differs with b's
+    // Count bits set quickly with a series of lookups:
+    return BITS_SET_IN_HALF_BYTE[a & 0x0F] +
+        BITS_SET_IN_HALF_BYTE[(a >>> 4 & 0x0F)] +
+        BITS_SET_IN_HALF_BYTE[(a >>> 8 & 0x0F)] +
+        BITS_SET_IN_HALF_BYTE[(a >>> 12 & 0x0F)] +
+        BITS_SET_IN_HALF_BYTE[(a >>> 16 & 0x0F)] +
+        BITS_SET_IN_HALF_BYTE[(a >>> 20 & 0x0F)] +
+        BITS_SET_IN_HALF_BYTE[(a >>> 24 & 0x0F)] +
+        BITS_SET_IN_HALF_BYTE[(a >>> 28 & 0x0F)];
+  }
+
+  /**
+   * @param maskedFormatInfo1 format info indicator, with mask still applied
+   * @param maskedFormatInfo2 second copy of same info; both are checked at the same time
+   *  to establish best match
+   * @return information about the format it specifies, or <code>null</code>
+   *  if doesn't seem to match any known pattern
+   */
+  static FormatInformation decodeFormatInformation(int maskedFormatInfo1, int maskedFormatInfo2) {
+    FormatInformation formatInfo = doDecodeFormatInformation(maskedFormatInfo1, maskedFormatInfo2);
+    if (formatInfo != null) {
+      return formatInfo;
+    }
+    // Should return null, but, some QR codes apparently
+    // do not mask this info. Try again by actually masking the pattern
+    // first
+    return doDecodeFormatInformation(maskedFormatInfo1 ^ FORMAT_INFO_MASK_QR,
+                                     maskedFormatInfo2 ^ FORMAT_INFO_MASK_QR);
+  }
+
+  private static FormatInformation doDecodeFormatInformation(int maskedFormatInfo1, int maskedFormatInfo2) {
+    // Find the int in FORMAT_INFO_DECODE_LOOKUP with fewest bits differing
+    int bestDifference = Integer.MAX_VALUE;
+    int bestFormatInfo = 0;
+    for (int i = 0; i < FORMAT_INFO_DECODE_LOOKUP.length; i++) {
+      int[] decodeInfo = FORMAT_INFO_DECODE_LOOKUP[i];
+      int targetInfo = decodeInfo[0];
+      if (targetInfo == maskedFormatInfo1 || targetInfo == maskedFormatInfo2) {
+        // Found an exact match
+        return new FormatInformation(decodeInfo[1]);
+      }
+      int bitsDifference = numBitsDiffering(maskedFormatInfo1, targetInfo);
+      if (bitsDifference < bestDifference) {
+        bestFormatInfo = decodeInfo[1];
+        bestDifference = bitsDifference;
+      }
+      if (maskedFormatInfo1 != maskedFormatInfo2) {
+        // also try the other option
+        bitsDifference = numBitsDiffering(maskedFormatInfo2, targetInfo);
+        if (bitsDifference < bestDifference) {
+          bestFormatInfo = decodeInfo[1];
+          bestDifference = bitsDifference;
+        }
+      }
+    }
+    // Hamming distance of the 32 masked codes is 7, by construction, so <= 3 bits
+    // differing means we found a match
+    if (bestDifference <= 3) {
+      return new FormatInformation(bestFormatInfo);
+    }
+    return null;
+  }
+
+  ErrorCorrectionLevel getErrorCorrectionLevel() {
+    return errorCorrectionLevel;
+  }
+
+  byte getDataMask() {
+    return dataMask;
+  }
+
+  public int hashCode() {
+    return (errorCorrectionLevel.ordinal() << 3) | (int) dataMask;
+  }
+
+  public boolean equals(Object o) {
+    if (!(o instanceof FormatInformation)) {
+      return false;
+    }
+    FormatInformation other = (FormatInformation) o;
+    return this.errorCorrectionLevel == other.errorCorrectionLevel &&
+        this.dataMask == other.dataMask;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/Mode.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.decoder;
+
+/**
+ * <p>See ISO 18004:2006, 6.4.1, Tables 2 and 3. This enum encapsulates the various modes in which
+ * data can be encoded to bits in the QR code standard.</p>
+ *
+ * @author Sean Owen
+ */
+public final class Mode {
+
+  // No, we can't use an enum here. J2ME doesn't support it.
+
+  public static final Mode TERMINATOR = new Mode(new int[]{0, 0, 0}, 0x00, "TERMINATOR"); // Not really a mode...
+  public static final Mode NUMERIC = new Mode(new int[]{10, 12, 14}, 0x01, "NUMERIC");
+  public static final Mode ALPHANUMERIC = new Mode(new int[]{9, 11, 13}, 0x02, "ALPHANUMERIC");
+  public static final Mode STRUCTURED_APPEND = new Mode(new int[]{0, 0, 0}, 0x03, "STRUCTURED_APPEND"); // Not supported
+  public static final Mode BYTE = new Mode(new int[]{8, 16, 16}, 0x04, "BYTE");
+  public static final Mode ECI = new Mode(null, 0x07, "ECI"); // character counts don't apply
+  public static final Mode KANJI = new Mode(new int[]{8, 10, 12}, 0x08, "KANJI");
+  public static final Mode FNC1_FIRST_POSITION = new Mode(null, 0x05, "FNC1_FIRST_POSITION");
+  public static final Mode FNC1_SECOND_POSITION = new Mode(null, 0x09, "FNC1_SECOND_POSITION");
+  /** See GBT 18284-2000; "Hanzi" is a transliteration of this mode name. */
+  public static final Mode HANZI = new Mode(new int[]{8, 10, 12}, 0x0D, "HANZI");
+
+  private final int[] characterCountBitsForVersions;
+  private final int bits;
+  private final String name;
+
+  private Mode(int[] characterCountBitsForVersions, int bits, String name) {
+    this.characterCountBitsForVersions = characterCountBitsForVersions;
+    this.bits = bits;
+    this.name = name;
+  }
+
+  /**
+   * @param bits four bits encoding a QR Code data mode
+   * @return Mode encoded by these bits
+   * @throws IllegalArgumentException if bits do not correspond to a known mode
+   */
+  public static Mode forBits(int bits) {
+    switch (bits) {
+      case 0x0:
+        return TERMINATOR;
+      case 0x1:
+        return NUMERIC;
+      case 0x2:
+        return ALPHANUMERIC;
+      case 0x3:
+        return STRUCTURED_APPEND;
+      case 0x4:
+        return BYTE;
+      case 0x5:
+        return FNC1_FIRST_POSITION;
+      case 0x7:
+        return ECI;
+      case 0x8:
+        return KANJI;
+      case 0x9:
+        return FNC1_SECOND_POSITION;
+      case 0xD:
+    	  // 0xD is defined in GBT 18284-2000, may not be supported in foreign country
+        return HANZI;
+      default:
+        throw new IllegalArgumentException();
+    }
+  }
+
+  /**
+   * @param version version in question
+   * @return number of bits used, in this QR Code symbol {@link Version}, to encode the
+   *         count of characters that will follow encoded in this Mode
+   */
+  public int getCharacterCountBits(Version version) {
+    if (characterCountBitsForVersions == null) {
+      throw new IllegalArgumentException("Character count doesn't apply to this mode");
+    }
+    int number = version.getVersionNumber();
+    int offset;
+    if (number <= 9) {
+      offset = 0;
+    } else if (number <= 26) {
+      offset = 1;
+    } else {
+      offset = 2;
+    }
+    return characterCountBitsForVersions[offset];
+  }
+
+  public int getBits() {
+    return bits;
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public String toString() {
+    return name;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/Version.java

@@ -0,0 +1,586 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.decoder;
+
+import com.google.zxing.FormatException;
+import com.google.zxing.common.BitMatrix;
+
+/**
+ * See ISO 18004:2006 Annex D
+ *
+ * @author Sean Owen
+ */
+public final class Version {
+
+  /**
+   * See ISO 18004:2006 Annex D.
+   * Element i represents the raw version bits that specify version i + 7
+   */
+  private static final int[] VERSION_DECODE_INFO = {
+      0x07C94, 0x085BC, 0x09A99, 0x0A4D3, 0x0BBF6,
+      0x0C762, 0x0D847, 0x0E60D, 0x0F928, 0x10B78,
+      0x1145D, 0x12A17, 0x13532, 0x149A6, 0x15683,
+      0x168C9, 0x177EC, 0x18EC4, 0x191E1, 0x1AFAB,
+      0x1B08E, 0x1CC1A, 0x1D33F, 0x1ED75, 0x1F250,
+      0x209D5, 0x216F0, 0x228BA, 0x2379F, 0x24B0B,
+      0x2542E, 0x26A64, 0x27541, 0x28C69
+  };
+
+  private static final Version[] VERSIONS = buildVersions();
+
+  private final int versionNumber;
+  private final int[] alignmentPatternCenters;
+  private final ECBlocks[] ecBlocks;
+  private final int totalCodewords;
+
+  private Version(int versionNumber,
+                  int[] alignmentPatternCenters,
+                  ECBlocks ecBlocks1,
+                  ECBlocks ecBlocks2,
+                  ECBlocks ecBlocks3,
+                  ECBlocks ecBlocks4) {
+    this.versionNumber = versionNumber;
+    this.alignmentPatternCenters = alignmentPatternCenters;
+    this.ecBlocks = new ECBlocks[]{ecBlocks1, ecBlocks2, ecBlocks3, ecBlocks4};
+    int total = 0;
+    int ecCodewords = ecBlocks1.getECCodewordsPerBlock();
+    ECB[] ecbArray = ecBlocks1.getECBlocks();
+    for (int i = 0; i < ecbArray.length; i++) {
+      ECB ecBlock = ecbArray[i];
+      total += ecBlock.getCount() * (ecBlock.getDataCodewords() + ecCodewords);
+    }
+    this.totalCodewords = total;
+  }
+
+  public int getVersionNumber() {
+    return versionNumber;
+  }
+
+  public int[] getAlignmentPatternCenters() {
+    return alignmentPatternCenters;
+  }
+
+  public int getTotalCodewords() {
+    return totalCodewords;
+  }
+
+  public int getDimensionForVersion() {
+    return 17 + 4 * versionNumber;
+  }
+
+  public ECBlocks getECBlocksForLevel(ErrorCorrectionLevel ecLevel) {
+    return ecBlocks[ecLevel.ordinal()];
+  }
+
+  /**
+   * <p>Deduces version information purely from QR Code dimensions.</p>
+   *
+   * @param dimension dimension in modules
+   * @return Version for a QR Code of that dimension
+   * @throws FormatException if dimension is not 1 mod 4
+   */
+  public static Version getProvisionalVersionForDimension(int dimension) throws FormatException {
+    if (dimension % 4 != 1) {
+      throw FormatException.getFormatInstance();
+    }
+    try {
+      return getVersionForNumber((dimension - 17) >> 2);
+    } catch (IllegalArgumentException iae) {
+      throw FormatException.getFormatInstance();
+    }
+  }
+
+  public static Version getVersionForNumber(int versionNumber) {
+    if (versionNumber < 1 || versionNumber > 40) {
+      throw new IllegalArgumentException();
+    }
+    return VERSIONS[versionNumber - 1];
+  }
+
+  static Version decodeVersionInformation(int versionBits) {
+    int bestDifference = Integer.MAX_VALUE;
+    int bestVersion = 0;
+    for (int i = 0; i < VERSION_DECODE_INFO.length; i++) {
+      int targetVersion = VERSION_DECODE_INFO[i];
+      // Do the version info bits match exactly? done.
+      if (targetVersion == versionBits) {
+        return getVersionForNumber(i + 7);
+      }
+      // Otherwise see if this is the closest to a real version info bit string
+      // we have seen so far
+      int bitsDifference = FormatInformation.numBitsDiffering(versionBits, targetVersion);
+      if (bitsDifference < bestDifference) {
+        bestVersion = i + 7;
+        bestDifference = bitsDifference;
+      }
+    }
+    // We can tolerate up to 3 bits of error since no two version info codewords will
+    // differ in less than 8 bits.
+    if (bestDifference <= 3) {
+      return getVersionForNumber(bestVersion);
+    }
+    // If we didn't find a close enough match, fail
+    return null;
+  }
+
+  /**
+   * See ISO 18004:2006 Annex E
+   */
+  BitMatrix buildFunctionPattern() {
+    int dimension = getDimensionForVersion();
+    BitMatrix bitMatrix = new BitMatrix(dimension);
+
+    // Top left finder pattern + separator + format
+    bitMatrix.setRegion(0, 0, 9, 9);
+    // Top right finder pattern + separator + format
+    bitMatrix.setRegion(dimension - 8, 0, 8, 9);
+    // Bottom left finder pattern + separator + format
+    bitMatrix.setRegion(0, dimension - 8, 9, 8);
+
+    // Alignment patterns
+    int max = alignmentPatternCenters.length;
+    for (int x = 0; x < max; x++) {
+      int i = alignmentPatternCenters[x] - 2;
+      for (int y = 0; y < max; y++) {
+        if ((x == 0 && (y == 0 || y == max - 1)) || (x == max - 1 && y == 0)) {
+          // No alignment patterns near the three finder paterns
+          continue;
+        }
+        bitMatrix.setRegion(alignmentPatternCenters[y] - 2, i, 5, 5);
+      }
+    }
+
+    // Vertical timing pattern
+    bitMatrix.setRegion(6, 9, 1, dimension - 17);
+    // Horizontal timing pattern
+    bitMatrix.setRegion(9, 6, dimension - 17, 1);
+
+    if (versionNumber > 6) {
+      // Version info, top right
+      bitMatrix.setRegion(dimension - 11, 0, 3, 6);
+      // Version info, bottom left
+      bitMatrix.setRegion(0, dimension - 11, 6, 3);
+    }
+
+    return bitMatrix;
+  }
+
+  /**
+   * <p>Encapsulates a set of error-correction blocks in one symbol version. Most versions will
+   * use blocks of differing sizes within one version, so, this encapsulates the parameters for
+   * each set of blocks. It also holds the number of error-correction codewords per block since it
+   * will be the same across all blocks within one version.</p>
+   */
+  public static final class ECBlocks {
+    private final int ecCodewordsPerBlock;
+    private final ECB[] ecBlocks;
+
+    ECBlocks(int ecCodewordsPerBlock, ECB ecBlocks) {
+      this.ecCodewordsPerBlock = ecCodewordsPerBlock;
+      this.ecBlocks = new ECB[]{ecBlocks};
+    }
+
+    ECBlocks(int ecCodewordsPerBlock, ECB ecBlocks1, ECB ecBlocks2) {
+      this.ecCodewordsPerBlock = ecCodewordsPerBlock;
+      this.ecBlocks = new ECB[]{ecBlocks1, ecBlocks2};
+    }
+
+    public int getECCodewordsPerBlock() {
+      return ecCodewordsPerBlock;
+    }
+
+    public int getNumBlocks() {
+      int total = 0;
+      for (int i = 0; i < ecBlocks.length; i++) {
+        total += ecBlocks[i].getCount();
+      }
+      return total;
+    }
+
+    public int getTotalECCodewords() {
+      return ecCodewordsPerBlock * getNumBlocks();
+    }
+
+    public ECB[] getECBlocks() {
+      return ecBlocks;
+    }
+  }
+
+  /**
+   * <p>Encapsualtes the parameters for one error-correction block in one symbol version.
+   * This includes the number of data codewords, and the number of times a block with these
+   * parameters is used consecutively in the QR code version's format.</p>
+   */
+  public static final class ECB {
+    private final int count;
+    private final int dataCodewords;
+
+    ECB(int count, int dataCodewords) {
+      this.count = count;
+      this.dataCodewords = dataCodewords;
+    }
+
+    public int getCount() {
+      return count;
+    }
+
+    public int getDataCodewords() {
+      return dataCodewords;
+    }
+  }
+
+  public String toString() {
+    return String.valueOf(versionNumber);
+  }
+
+  /**
+   * See ISO 18004:2006 6.5.1 Table 9
+   */
+  private static Version[] buildVersions() {
+    return new Version[]{
+        new Version(1, new int[]{},
+            new ECBlocks(7, new ECB(1, 19)),
+            new ECBlocks(10, new ECB(1, 16)),
+            new ECBlocks(13, new ECB(1, 13)),
+            new ECBlocks(17, new ECB(1, 9))),
+        new Version(2, new int[]{6, 18},
+            new ECBlocks(10, new ECB(1, 34)),
+            new ECBlocks(16, new ECB(1, 28)),
+            new ECBlocks(22, new ECB(1, 22)),
+            new ECBlocks(28, new ECB(1, 16))),
+        new Version(3, new int[]{6, 22},
+            new ECBlocks(15, new ECB(1, 55)),
+            new ECBlocks(26, new ECB(1, 44)),
+            new ECBlocks(18, new ECB(2, 17)),
+            new ECBlocks(22, new ECB(2, 13))),
+        new Version(4, new int[]{6, 26},
+            new ECBlocks(20, new ECB(1, 80)),
+            new ECBlocks(18, new ECB(2, 32)),
+            new ECBlocks(26, new ECB(2, 24)),
+            new ECBlocks(16, new ECB(4, 9))),
+        new Version(5, new int[]{6, 30},
+            new ECBlocks(26, new ECB(1, 108)),
+            new ECBlocks(24, new ECB(2, 43)),
+            new ECBlocks(18, new ECB(2, 15),
+                new ECB(2, 16)),
+            new ECBlocks(22, new ECB(2, 11),
+                new ECB(2, 12))),
+        new Version(6, new int[]{6, 34},
+            new ECBlocks(18, new ECB(2, 68)),
+            new ECBlocks(16, new ECB(4, 27)),
+            new ECBlocks(24, new ECB(4, 19)),
+            new ECBlocks(28, new ECB(4, 15))),
+        new Version(7, new int[]{6, 22, 38},
+            new ECBlocks(20, new ECB(2, 78)),
+            new ECBlocks(18, new ECB(4, 31)),
+            new ECBlocks(18, new ECB(2, 14),
+                new ECB(4, 15)),
+            new ECBlocks(26, new ECB(4, 13),
+                new ECB(1, 14))),
+        new Version(8, new int[]{6, 24, 42},
+            new ECBlocks(24, new ECB(2, 97)),
+            new ECBlocks(22, new ECB(2, 38),
+                new ECB(2, 39)),
+            new ECBlocks(22, new ECB(4, 18),
+                new ECB(2, 19)),
+            new ECBlocks(26, new ECB(4, 14),
+                new ECB(2, 15))),
+        new Version(9, new int[]{6, 26, 46},
+            new ECBlocks(30, new ECB(2, 116)),
+            new ECBlocks(22, new ECB(3, 36),
+                new ECB(2, 37)),
+            new ECBlocks(20, new ECB(4, 16),
+                new ECB(4, 17)),
+            new ECBlocks(24, new ECB(4, 12),
+                new ECB(4, 13))),
+        new Version(10, new int[]{6, 28, 50},
+            new ECBlocks(18, new ECB(2, 68),
+                new ECB(2, 69)),
+            new ECBlocks(26, new ECB(4, 43),
+                new ECB(1, 44)),
+            new ECBlocks(24, new ECB(6, 19),
+                new ECB(2, 20)),
+            new ECBlocks(28, new ECB(6, 15),
+                new ECB(2, 16))),
+        new Version(11, new int[]{6, 30, 54},
+            new ECBlocks(20, new ECB(4, 81)),
+            new ECBlocks(30, new ECB(1, 50),
+                new ECB(4, 51)),
+            new ECBlocks(28, new ECB(4, 22),
+                new ECB(4, 23)),
+            new ECBlocks(24, new ECB(3, 12),
+                new ECB(8, 13))),
+        new Version(12, new int[]{6, 32, 58},
+            new ECBlocks(24, new ECB(2, 92),
+                new ECB(2, 93)),
+            new ECBlocks(22, new ECB(6, 36),
+                new ECB(2, 37)),
+            new ECBlocks(26, new ECB(4, 20),
+                new ECB(6, 21)),
+            new ECBlocks(28, new ECB(7, 14),
+                new ECB(4, 15))),
+        new Version(13, new int[]{6, 34, 62},
+            new ECBlocks(26, new ECB(4, 107)),
+            new ECBlocks(22, new ECB(8, 37),
+                new ECB(1, 38)),
+            new ECBlocks(24, new ECB(8, 20),
+                new ECB(4, 21)),
+            new ECBlocks(22, new ECB(12, 11),
+                new ECB(4, 12))),
+        new Version(14, new int[]{6, 26, 46, 66},
+            new ECBlocks(30, new ECB(3, 115),
+                new ECB(1, 116)),
+            new ECBlocks(24, new ECB(4, 40),
+                new ECB(5, 41)),
+            new ECBlocks(20, new ECB(11, 16),
+                new ECB(5, 17)),
+            new ECBlocks(24, new ECB(11, 12),
+                new ECB(5, 13))),
+        new Version(15, new int[]{6, 26, 48, 70},
+            new ECBlocks(22, new ECB(5, 87),
+                new ECB(1, 88)),
+            new ECBlocks(24, new ECB(5, 41),
+                new ECB(5, 42)),
+            new ECBlocks(30, new ECB(5, 24),
+                new ECB(7, 25)),
+            new ECBlocks(24, new ECB(11, 12),
+                new ECB(7, 13))),
+        new Version(16, new int[]{6, 26, 50, 74},
+            new ECBlocks(24, new ECB(5, 98),
+                new ECB(1, 99)),
+            new ECBlocks(28, new ECB(7, 45),
+                new ECB(3, 46)),
+            new ECBlocks(24, new ECB(15, 19),
+                new ECB(2, 20)),
+            new ECBlocks(30, new ECB(3, 15),
+                new ECB(13, 16))),
+        new Version(17, new int[]{6, 30, 54, 78},
+            new ECBlocks(28, new ECB(1, 107),
+                new ECB(5, 108)),
+            new ECBlocks(28, new ECB(10, 46),
+                new ECB(1, 47)),
+            new ECBlocks(28, new ECB(1, 22),
+                new ECB(15, 23)),
+            new ECBlocks(28, new ECB(2, 14),
+                new ECB(17, 15))),
+        new Version(18, new int[]{6, 30, 56, 82},
+            new ECBlocks(30, new ECB(5, 120),
+                new ECB(1, 121)),
+            new ECBlocks(26, new ECB(9, 43),
+                new ECB(4, 44)),
+            new ECBlocks(28, new ECB(17, 22),
+                new ECB(1, 23)),
+            new ECBlocks(28, new ECB(2, 14),
+                new ECB(19, 15))),
+        new Version(19, new int[]{6, 30, 58, 86},
+            new ECBlocks(28, new ECB(3, 113),
+                new ECB(4, 114)),
+            new ECBlocks(26, new ECB(3, 44),
+                new ECB(11, 45)),
+            new ECBlocks(26, new ECB(17, 21),
+                new ECB(4, 22)),
+            new ECBlocks(26, new ECB(9, 13),
+                new ECB(16, 14))),
+        new Version(20, new int[]{6, 34, 62, 90},
+            new ECBlocks(28, new ECB(3, 107),
+                new ECB(5, 108)),
+            new ECBlocks(26, new ECB(3, 41),
+                new ECB(13, 42)),
+            new ECBlocks(30, new ECB(15, 24),
+                new ECB(5, 25)),
+            new ECBlocks(28, new ECB(15, 15),
+                new ECB(10, 16))),
+        new Version(21, new int[]{6, 28, 50, 72, 94},
+            new ECBlocks(28, new ECB(4, 116),
+                new ECB(4, 117)),
+            new ECBlocks(26, new ECB(17, 42)),
+            new ECBlocks(28, new ECB(17, 22),
+                new ECB(6, 23)),
+            new ECBlocks(30, new ECB(19, 16),
+                new ECB(6, 17))),
+        new Version(22, new int[]{6, 26, 50, 74, 98},
+            new ECBlocks(28, new ECB(2, 111),
+                new ECB(7, 112)),
+            new ECBlocks(28, new ECB(17, 46)),
+            new ECBlocks(30, new ECB(7, 24),
+                new ECB(16, 25)),
+            new ECBlocks(24, new ECB(34, 13))),
+        new Version(23, new int[]{6, 30, 54, 78, 102},
+            new ECBlocks(30, new ECB(4, 121),
+                new ECB(5, 122)),
+            new ECBlocks(28, new ECB(4, 47),
+                new ECB(14, 48)),
+            new ECBlocks(30, new ECB(11, 24),
+                new ECB(14, 25)),
+            new ECBlocks(30, new ECB(16, 15),
+                new ECB(14, 16))),
+        new Version(24, new int[]{6, 28, 54, 80, 106},
+            new ECBlocks(30, new ECB(6, 117),
+                new ECB(4, 118)),
+            new ECBlocks(28, new ECB(6, 45),
+                new ECB(14, 46)),
+            new ECBlocks(30, new ECB(11, 24),
+                new ECB(16, 25)),
+            new ECBlocks(30, new ECB(30, 16),
+                new ECB(2, 17))),
+        new Version(25, new int[]{6, 32, 58, 84, 110},
+            new ECBlocks(26, new ECB(8, 106),
+                new ECB(4, 107)),
+            new ECBlocks(28, new ECB(8, 47),
+                new ECB(13, 48)),
+            new ECBlocks(30, new ECB(7, 24),
+                new ECB(22, 25)),
+            new ECBlocks(30, new ECB(22, 15),
+                new ECB(13, 16))),
+        new Version(26, new int[]{6, 30, 58, 86, 114},
+            new ECBlocks(28, new ECB(10, 114),
+                new ECB(2, 115)),
+            new ECBlocks(28, new ECB(19, 46),
+                new ECB(4, 47)),
+            new ECBlocks(28, new ECB(28, 22),
+                new ECB(6, 23)),
+            new ECBlocks(30, new ECB(33, 16),
+                new ECB(4, 17))),
+        new Version(27, new int[]{6, 34, 62, 90, 118},
+            new ECBlocks(30, new ECB(8, 122),
+                new ECB(4, 123)),
+            new ECBlocks(28, new ECB(22, 45),
+                new ECB(3, 46)),
+            new ECBlocks(30, new ECB(8, 23),
+                new ECB(26, 24)),
+            new ECBlocks(30, new ECB(12, 15),
+                new ECB(28, 16))),
+        new Version(28, new int[]{6, 26, 50, 74, 98, 122},
+            new ECBlocks(30, new ECB(3, 117),
+                new ECB(10, 118)),
+            new ECBlocks(28, new ECB(3, 45),
+                new ECB(23, 46)),
+            new ECBlocks(30, new ECB(4, 24),
+                new ECB(31, 25)),
+            new ECBlocks(30, new ECB(11, 15),
+                new ECB(31, 16))),
+        new Version(29, new int[]{6, 30, 54, 78, 102, 126},
+            new ECBlocks(30, new ECB(7, 116),
+                new ECB(7, 117)),
+            new ECBlocks(28, new ECB(21, 45),
+                new ECB(7, 46)),
+            new ECBlocks(30, new ECB(1, 23),
+                new ECB(37, 24)),
+            new ECBlocks(30, new ECB(19, 15),
+                new ECB(26, 16))),
+        new Version(30, new int[]{6, 26, 52, 78, 104, 130},
+            new ECBlocks(30, new ECB(5, 115),
+                new ECB(10, 116)),
+            new ECBlocks(28, new ECB(19, 47),
+                new ECB(10, 48)),
+            new ECBlocks(30, new ECB(15, 24),
+                new ECB(25, 25)),
+            new ECBlocks(30, new ECB(23, 15),
+                new ECB(25, 16))),
+        new Version(31, new int[]{6, 30, 56, 82, 108, 134},
+            new ECBlocks(30, new ECB(13, 115),
+                new ECB(3, 116)),
+            new ECBlocks(28, new ECB(2, 46),
+                new ECB(29, 47)),
+            new ECBlocks(30, new ECB(42, 24),
+                new ECB(1, 25)),
+            new ECBlocks(30, new ECB(23, 15),
+                new ECB(28, 16))),
+        new Version(32, new int[]{6, 34, 60, 86, 112, 138},
+            new ECBlocks(30, new ECB(17, 115)),
+            new ECBlocks(28, new ECB(10, 46),
+                new ECB(23, 47)),
+            new ECBlocks(30, new ECB(10, 24),
+                new ECB(35, 25)),
+            new ECBlocks(30, new ECB(19, 15),
+                new ECB(35, 16))),
+        new Version(33, new int[]{6, 30, 58, 86, 114, 142},
+            new ECBlocks(30, new ECB(17, 115),
+                new ECB(1, 116)),
+            new ECBlocks(28, new ECB(14, 46),
+                new ECB(21, 47)),
+            new ECBlocks(30, new ECB(29, 24),
+                new ECB(19, 25)),
+            new ECBlocks(30, new ECB(11, 15),
+                new ECB(46, 16))),
+        new Version(34, new int[]{6, 34, 62, 90, 118, 146},
+            new ECBlocks(30, new ECB(13, 115),
+                new ECB(6, 116)),
+            new ECBlocks(28, new ECB(14, 46),
+                new ECB(23, 47)),
+            new ECBlocks(30, new ECB(44, 24),
+                new ECB(7, 25)),
+            new ECBlocks(30, new ECB(59, 16),
+                new ECB(1, 17))),
+        new Version(35, new int[]{6, 30, 54, 78, 102, 126, 150},
+            new ECBlocks(30, new ECB(12, 121),
+                new ECB(7, 122)),
+            new ECBlocks(28, new ECB(12, 47),
+                new ECB(26, 48)),
+            new ECBlocks(30, new ECB(39, 24),
+                new ECB(14, 25)),
+            new ECBlocks(30, new ECB(22, 15),
+                new ECB(41, 16))),
+        new Version(36, new int[]{6, 24, 50, 76, 102, 128, 154},
+            new ECBlocks(30, new ECB(6, 121),
+                new ECB(14, 122)),
+            new ECBlocks(28, new ECB(6, 47),
+                new ECB(34, 48)),
+            new ECBlocks(30, new ECB(46, 24),
+                new ECB(10, 25)),
+            new ECBlocks(30, new ECB(2, 15),
+                new ECB(64, 16))),
+        new Version(37, new int[]{6, 28, 54, 80, 106, 132, 158},
+            new ECBlocks(30, new ECB(17, 122),
+                new ECB(4, 123)),
+            new ECBlocks(28, new ECB(29, 46),
+                new ECB(14, 47)),
+            new ECBlocks(30, new ECB(49, 24),
+                new ECB(10, 25)),
+            new ECBlocks(30, new ECB(24, 15),
+                new ECB(46, 16))),
+        new Version(38, new int[]{6, 32, 58, 84, 110, 136, 162},
+            new ECBlocks(30, new ECB(4, 122),
+                new ECB(18, 123)),
+            new ECBlocks(28, new ECB(13, 46),
+                new ECB(32, 47)),
+            new ECBlocks(30, new ECB(48, 24),
+                new ECB(14, 25)),
+            new ECBlocks(30, new ECB(42, 15),
+                new ECB(32, 16))),
+        new Version(39, new int[]{6, 26, 54, 82, 110, 138, 166},
+            new ECBlocks(30, new ECB(20, 117),
+                new ECB(4, 118)),
+            new ECBlocks(28, new ECB(40, 47),
+                new ECB(7, 48)),
+            new ECBlocks(30, new ECB(43, 24),
+                new ECB(22, 25)),
+            new ECBlocks(30, new ECB(10, 15),
+                new ECB(67, 16))),
+        new Version(40, new int[]{6, 30, 58, 86, 114, 142, 170},
+            new ECBlocks(30, new ECB(19, 118),
+                new ECB(6, 119)),
+            new ECBlocks(28, new ECB(18, 47),
+                new ECB(31, 48)),
+            new ECBlocks(30, new ECB(34, 24),
+                new ECB(34, 25)),
+            new ECBlocks(30, new ECB(20, 15),
+                new ECB(61, 16)))
+    };
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/detector/AlignmentPattern.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.detector;
+
+import com.google.zxing.ResultPoint;
+
+/**
+ * <p>Encapsulates an alignment pattern, which are the smaller square patterns found in
+ * all but the simplest QR Codes.</p>
+ *
+ * @author Sean Owen
+ */
+public final class AlignmentPattern extends ResultPoint {
+
+  private final float estimatedModuleSize;
+
+  AlignmentPattern(float posX, float posY, float estimatedModuleSize) {
+    super(posX, posY);
+    this.estimatedModuleSize = estimatedModuleSize;
+  }
+
+  /**
+   * <p>Determines if this alignment pattern "about equals" an alignment pattern at the stated
+   * position and size -- meaning, it is at nearly the same center with nearly the same size.</p>
+   */
+  boolean aboutEquals(float moduleSize, float i, float j) {
+    if (Math.abs(i - getY()) <= moduleSize && Math.abs(j - getX()) <= moduleSize) {
+      float moduleSizeDiff = Math.abs(moduleSize - estimatedModuleSize);
+      return moduleSizeDiff <= 1.0f || moduleSizeDiff / estimatedModuleSize <= 1.0f;
+    }
+    return false;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/detector/AlignmentPatternFinder.java

@@ -0,0 +1,279 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.detector;
+
+import com.google.zxing.NotFoundException;
+import com.google.zxing.ResultPoint;
+import com.google.zxing.ResultPointCallback;
+import com.google.zxing.common.BitMatrix;
+
+import java.util.Vector;
+
+/**
+ * <p>This class attempts to find alignment patterns in a QR Code. Alignment patterns look like finder
+ * patterns but are smaller and appear at regular intervals throughout the image.</p>
+ *
+ * <p>At the moment this only looks for the bottom-right alignment pattern.</p>
+ *
+ * <p>This is mostly a simplified copy of {@link FinderPatternFinder}. It is copied,
+ * pasted and stripped down here for maximum performance but does unfortunately duplicate
+ * some code.</p>
+ *
+ * <p>This class is thread-safe but not reentrant. Each thread must allocate its own object.
+ *
+ * @author Sean Owen
+ */
+final class AlignmentPatternFinder {
+
+  private final BitMatrix image;
+  private final Vector possibleCenters;
+  private final int startX;
+  private final int startY;
+  private final int width;
+  private final int height;
+  private final float moduleSize;
+  private final int[] crossCheckStateCount;
+  private final ResultPointCallback resultPointCallback;
+
+  /**
+   * <p>Creates a finder that will look in a portion of the whole image.</p>
+   *
+   * @param image image to search
+   * @param startX left column from which to start searching
+   * @param startY top row from which to start searching
+   * @param width width of region to search
+   * @param height height of region to search
+   * @param moduleSize estimated module size so far
+   */
+  AlignmentPatternFinder(BitMatrix image,
+                         int startX,
+                         int startY,
+                         int width,
+                         int height,
+                         float moduleSize,
+                         ResultPointCallback resultPointCallback) {
+    this.image = image;
+    this.possibleCenters = new Vector(5);
+    this.startX = startX;
+    this.startY = startY;
+    this.width = width;
+    this.height = height;
+    this.moduleSize = moduleSize;
+    this.crossCheckStateCount = new int[3];
+    this.resultPointCallback = resultPointCallback;
+  }
+
+  /**
+   * <p>This method attempts to find the bottom-right alignment pattern in the image. It is a bit messy since
+   * it's pretty performance-critical and so is written to be fast foremost.</p>
+   *
+   * @return {@link AlignmentPattern} if found
+   * @throws NotFoundException if not found
+   */
+  AlignmentPattern find() throws NotFoundException {
+    int startX = this.startX;
+    int height = this.height;
+    int maxJ = startX + width;
+    int middleI = startY + (height >> 1);
+    // We are looking for black/white/black modules in 1:1:1 ratio;
+    // this tracks the number of black/white/black modules seen so far
+    int[] stateCount = new int[3];
+    for (int iGen = 0; iGen < height; iGen++) {
+      // Search from middle outwards
+      int i = middleI + ((iGen & 0x01) == 0 ? (iGen + 1) >> 1 : -((iGen + 1) >> 1));
+      stateCount[0] = 0;
+      stateCount[1] = 0;
+      stateCount[2] = 0;
+      int j = startX;
+      // Burn off leading white pixels before anything else; if we start in the middle of
+      // a white run, it doesn't make sense to count its length, since we don't know if the
+      // white run continued to the left of the start point
+      while (j < maxJ && !image.get(j, i)) {
+        j++;
+      }
+      int currentState = 0;
+      while (j < maxJ) {
+        if (image.get(j, i)) {
+          // Black pixel
+          if (currentState == 1) { // Counting black pixels
+            stateCount[currentState]++;
+          } else { // Counting white pixels
+            if (currentState == 2) { // A winner?
+              if (foundPatternCross(stateCount)) { // Yes
+                AlignmentPattern confirmed = handlePossibleCenter(stateCount, i, j);
+                if (confirmed != null) {
+                  return confirmed;
+                }
+              }
+              stateCount[0] = stateCount[2];
+              stateCount[1] = 1;
+              stateCount[2] = 0;
+              currentState = 1;
+            } else {
+              stateCount[++currentState]++;
+            }
+          }
+        } else { // White pixel
+          if (currentState == 1) { // Counting black pixels
+            currentState++;
+          }
+          stateCount[currentState]++;
+        }
+        j++;
+      }
+      if (foundPatternCross(stateCount)) {
+        AlignmentPattern confirmed = handlePossibleCenter(stateCount, i, maxJ);
+        if (confirmed != null) {
+          return confirmed;
+        }
+      }
+
+    }
+
+    // Hmm, nothing we saw was observed and confirmed twice. If we had
+    // any guess at all, return it.
+    if (!possibleCenters.isEmpty()) {
+      return (AlignmentPattern) possibleCenters.elementAt(0);
+    }
+
+    throw NotFoundException.getNotFoundInstance();
+  }
+
+  /**
+   * Given a count of black/white/black pixels just seen and an end position,
+   * figures the location of the center of this black/white/black run.
+   */
+  private static float centerFromEnd(int[] stateCount, int end) {
+    return (float) (end - stateCount[2]) - stateCount[1] / 2.0f;
+  }
+
+  /**
+   * @param stateCount count of black/white/black pixels just read
+   * @return true iff the proportions of the counts is close enough to the 1/1/1 ratios
+   *         used by alignment patterns to be considered a match
+   */
+  private boolean foundPatternCross(int[] stateCount) {
+    float moduleSize = this.moduleSize;
+    float maxVariance = moduleSize / 2.0f;
+    for (int i = 0; i < 3; i++) {
+      if (Math.abs(moduleSize - stateCount[i]) >= maxVariance) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  /**
+   * <p>After a horizontal scan finds a potential alignment pattern, this method
+   * "cross-checks" by scanning down vertically through the center of the possible
+   * alignment pattern to see if the same proportion is detected.</p>
+   *
+   * @param startI row where an alignment pattern was detected
+   * @param centerJ center of the section that appears to cross an alignment pattern
+   * @param maxCount maximum reasonable number of modules that should be
+   * observed in any reading state, based on the results of the horizontal scan
+   * @return vertical center of alignment pattern, or {@link Float#NaN} if not found
+   */
+  private float crossCheckVertical(int startI, int centerJ, int maxCount,
+      int originalStateCountTotal) {
+    BitMatrix image = this.image;
+
+    int maxI = image.getHeight();
+    int[] stateCount = crossCheckStateCount;
+    stateCount[0] = 0;
+    stateCount[1] = 0;
+    stateCount[2] = 0;
+
+    // Start counting up from center
+    int i = startI;
+    while (i >= 0 && image.get(centerJ, i) && stateCount[1] <= maxCount) {
+      stateCount[1]++;
+      i--;
+    }
+    // If already too many modules in this state or ran off the edge:
+    if (i < 0 || stateCount[1] > maxCount) {
+      return Float.NaN;
+    }
+    while (i >= 0 && !image.get(centerJ, i) && stateCount[0] <= maxCount) {
+      stateCount[0]++;
+      i--;
+    }
+    if (stateCount[0] > maxCount) {
+      return Float.NaN;
+    }
+
+    // Now also count down from center
+    i = startI + 1;
+    while (i < maxI && image.get(centerJ, i) && stateCount[1] <= maxCount) {
+      stateCount[1]++;
+      i++;
+    }
+    if (i == maxI || stateCount[1] > maxCount) {
+      return Float.NaN;
+    }
+    while (i < maxI && !image.get(centerJ, i) && stateCount[2] <= maxCount) {
+      stateCount[2]++;
+      i++;
+    }
+    if (stateCount[2] > maxCount) {
+      return Float.NaN;
+    }
+
+    int stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2];
+    if (5 * Math.abs(stateCountTotal - originalStateCountTotal) >= 2 * originalStateCountTotal) {
+      return Float.NaN;
+    }
+
+    return foundPatternCross(stateCount) ? centerFromEnd(stateCount, i) : Float.NaN;
+  }
+
+  /**
+   * <p>This is called when a horizontal scan finds a possible alignment pattern. It will
+   * cross check with a vertical scan, and if successful, will see if this pattern had been
+   * found on a previous horizontal scan. If so, we consider it confirmed and conclude we have
+   * found the alignment pattern.</p>
+   *
+   * @param stateCount reading state module counts from horizontal scan
+   * @param i row where alignment pattern may be found
+   * @param j end of possible alignment pattern in row
+   * @return {@link AlignmentPattern} if we have found the same pattern twice, or null if not
+   */
+  private AlignmentPattern handlePossibleCenter(int[] stateCount, int i, int j) {
+    int stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2];
+    float centerJ = centerFromEnd(stateCount, j);
+    float centerI = crossCheckVertical(i, (int) centerJ, 2 * stateCount[1], stateCountTotal);
+    if (!Float.isNaN(centerI)) {
+      float estimatedModuleSize = (float) (stateCount[0] + stateCount[1] + stateCount[2]) / 3.0f;
+      int max = possibleCenters.size();
+      for (int index = 0; index < max; index++) {
+        AlignmentPattern center = (AlignmentPattern) possibleCenters.elementAt(index);
+        // Look for about the same center and module size:
+        if (center.aboutEquals(estimatedModuleSize, centerI, centerJ)) {
+          return new AlignmentPattern(centerJ, centerI, estimatedModuleSize);
+        }
+      }
+      // Hadn't found this before; save it
+      ResultPoint point = new AlignmentPattern(centerJ, centerI, estimatedModuleSize);
+      possibleCenters.addElement(point);
+      if (resultPointCallback != null) {
+        resultPointCallback.foundPossibleResultPoint(point);
+      }
+    }
+    return null;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/detector/Detector.java

@@ -0,0 +1,406 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.detector;
+
+import com.google.zxing.DecodeHintType;
+import com.google.zxing.FormatException;
+import com.google.zxing.NotFoundException;
+import com.google.zxing.ResultPoint;
+import com.google.zxing.ResultPointCallback;
+import com.google.zxing.common.BitMatrix;
+import com.google.zxing.common.DetectorResult;
+import com.google.zxing.common.GridSampler;
+import com.google.zxing.common.PerspectiveTransform;
+import com.google.zxing.qrcode.decoder.Version;
+
+import java.util.Hashtable;
+
+/**
+ * <p>Encapsulates logic that can detect a QR Code in an image, even if the QR Code
+ * is rotated or skewed, or partially obscured.</p>
+ *
+ * @author Sean Owen
+ */
+public class Detector {
+
+  private final BitMatrix image;
+  private ResultPointCallback resultPointCallback;
+
+  public Detector(BitMatrix image) {
+    this.image = image;
+  }
+
+  protected BitMatrix getImage() {
+    return image;
+  }
+
+  protected ResultPointCallback getResultPointCallback() {
+    return resultPointCallback;
+  }
+
+  /**
+   * <p>Detects a QR Code in an image, simply.</p>
+   *
+   * @return {@link DetectorResult} encapsulating results of detecting a QR Code
+   * @throws NotFoundException if no QR Code can be found
+   */
+  public DetectorResult detect() throws NotFoundException, FormatException {
+    return detect(null);
+  }
+
+  /**
+   * <p>Detects a QR Code in an image, simply.</p>
+   *
+   * @param hints optional hints to detector
+   * @return {@link NotFoundException} encapsulating results of detecting a QR Code
+   * @throws NotFoundException if QR Code cannot be found
+   * @throws FormatException if a QR Code cannot be decoded
+   */
+  public DetectorResult detect(Hashtable hints) throws NotFoundException, FormatException {
+
+    resultPointCallback = hints == null ? null :
+        (ResultPointCallback) hints.get(DecodeHintType.NEED_RESULT_POINT_CALLBACK);
+
+    FinderPatternFinder finder = new FinderPatternFinder(image, resultPointCallback);
+    FinderPatternInfo info = finder.find(hints);
+
+    return processFinderPatternInfo(info);
+  }
+
+  protected DetectorResult processFinderPatternInfo(FinderPatternInfo info)
+      throws NotFoundException, FormatException {
+
+    FinderPattern topLeft = info.getTopLeft();
+    FinderPattern topRight = info.getTopRight();
+    FinderPattern bottomLeft = info.getBottomLeft();
+
+    float moduleSize = calculateModuleSize(topLeft, topRight, bottomLeft);
+    if (moduleSize < 1.0f) {
+      throw NotFoundException.getNotFoundInstance();
+    }
+    int dimension = computeDimension(topLeft, topRight, bottomLeft, moduleSize);
+    Version provisionalVersion = Version.getProvisionalVersionForDimension(dimension);
+    int modulesBetweenFPCenters = provisionalVersion.getDimensionForVersion() - 7;
+
+    AlignmentPattern alignmentPattern = null;
+    // Anything above version 1 has an alignment pattern
+    if (provisionalVersion.getAlignmentPatternCenters().length > 0) {
+
+      // Guess where a "bottom right" finder pattern would have been
+      float bottomRightX = topRight.getX() - topLeft.getX() + bottomLeft.getX();
+      float bottomRightY = topRight.getY() - topLeft.getY() + bottomLeft.getY();
+
+      // Estimate that alignment pattern is closer by 3 modules
+      // from "bottom right" to known top left location
+      float correctionToTopLeft = 1.0f - 3.0f / (float) modulesBetweenFPCenters;
+      int estAlignmentX = (int) (topLeft.getX() + correctionToTopLeft * (bottomRightX - topLeft.getX()));
+      int estAlignmentY = (int) (topLeft.getY() + correctionToTopLeft * (bottomRightY - topLeft.getY()));
+
+      // Kind of arbitrary -- expand search radius before giving up
+      for (int i = 4; i <= 16; i <<= 1) {
+        try {
+          alignmentPattern = findAlignmentInRegion(moduleSize,
+              estAlignmentX,
+              estAlignmentY,
+              (float) i);
+          break;
+        } catch (NotFoundException re) {
+          // try next round
+        }
+      }
+      // If we didn't find alignment pattern... well try anyway without it
+    }
+
+    PerspectiveTransform transform =
+        createTransform(topLeft, topRight, bottomLeft, alignmentPattern, dimension);
+
+    BitMatrix bits = sampleGrid(image, transform, dimension);
+
+    ResultPoint[] points;
+    if (alignmentPattern == null) {
+      points = new ResultPoint[]{bottomLeft, topLeft, topRight};
+    } else {
+      points = new ResultPoint[]{bottomLeft, topLeft, topRight, alignmentPattern};
+    }
+    return new DetectorResult(bits, points);
+  }
+
+  public static PerspectiveTransform createTransform(ResultPoint topLeft,
+                                                     ResultPoint topRight,
+                                                     ResultPoint bottomLeft,
+                                                     ResultPoint alignmentPattern,
+                                                     int dimension) {
+    float dimMinusThree = (float) dimension - 3.5f;
+    float bottomRightX;
+    float bottomRightY;
+    float sourceBottomRightX;
+    float sourceBottomRightY;
+    if (alignmentPattern != null) {
+      bottomRightX = alignmentPattern.getX();
+      bottomRightY = alignmentPattern.getY();
+      sourceBottomRightX = sourceBottomRightY = dimMinusThree - 3.0f;
+    } else {
+      // Don't have an alignment pattern, just make up the bottom-right point
+      bottomRightX = (topRight.getX() - topLeft.getX()) + bottomLeft.getX();
+      bottomRightY = (topRight.getY() - topLeft.getY()) + bottomLeft.getY();
+      sourceBottomRightX = sourceBottomRightY = dimMinusThree;
+    }
+
+    return PerspectiveTransform.quadrilateralToQuadrilateral(
+        3.5f,
+        3.5f,
+        dimMinusThree,
+        3.5f,
+        sourceBottomRightX,
+        sourceBottomRightY,
+        3.5f,
+        dimMinusThree,
+        topLeft.getX(),
+        topLeft.getY(),
+        topRight.getX(),
+        topRight.getY(),
+        bottomRightX,
+        bottomRightY,
+        bottomLeft.getX(),
+        bottomLeft.getY());
+  }
+
+  private static BitMatrix sampleGrid(BitMatrix image,
+                                      PerspectiveTransform transform,
+                                      int dimension) throws NotFoundException {
+
+    GridSampler sampler = GridSampler.getInstance();
+    return sampler.sampleGrid(image, dimension, dimension, transform);
+  }
+
+  /**
+   * <p>Computes the dimension (number of modules on a size) of the QR Code based on the position
+   * of the finder patterns and estimated module size.</p>
+   */
+  protected static int computeDimension(ResultPoint topLeft,
+                                        ResultPoint topRight,
+                                        ResultPoint bottomLeft,
+                                      float moduleSize) throws NotFoundException {
+    int tltrCentersDimension = round(ResultPoint.distance(topLeft, topRight) / moduleSize);
+    int tlblCentersDimension = round(ResultPoint.distance(topLeft, bottomLeft) / moduleSize);
+    int dimension = ((tltrCentersDimension + tlblCentersDimension) >> 1) + 7;
+    switch (dimension & 0x03) { // mod 4
+      case 0:
+        dimension++;
+        break;
+        // 1? do nothing
+      case 2:
+        dimension--;
+        break;
+      case 3:
+        throw NotFoundException.getNotFoundInstance();
+    }
+    return dimension;
+  }
+
+  /**
+   * <p>Computes an average estimated module size based on estimated derived from the positions
+   * of the three finder patterns.</p>
+   */
+  protected float calculateModuleSize(ResultPoint topLeft,
+                                      ResultPoint topRight,
+                                      ResultPoint bottomLeft) {
+    // Take the average
+    return (calculateModuleSizeOneWay(topLeft, topRight) +
+        calculateModuleSizeOneWay(topLeft, bottomLeft)) / 2.0f;
+  }
+
+  /**
+   * <p>Estimates module size based on two finder patterns -- it uses
+   * {@link #sizeOfBlackWhiteBlackRunBothWays(int, int, int, int)} to figure the
+   * width of each, measuring along the axis between their centers.</p>
+   */
+  private float calculateModuleSizeOneWay(ResultPoint pattern, ResultPoint otherPattern) {
+    float moduleSizeEst1 = sizeOfBlackWhiteBlackRunBothWays((int) pattern.getX(),
+        (int) pattern.getY(),
+        (int) otherPattern.getX(),
+        (int) otherPattern.getY());
+    float moduleSizeEst2 = sizeOfBlackWhiteBlackRunBothWays((int) otherPattern.getX(),
+        (int) otherPattern.getY(),
+        (int) pattern.getX(),
+        (int) pattern.getY());
+    if (Float.isNaN(moduleSizeEst1)) {
+      return moduleSizeEst2 / 7.0f;
+    }
+    if (Float.isNaN(moduleSizeEst2)) {
+      return moduleSizeEst1 / 7.0f;
+    }
+    // Average them, and divide by 7 since we've counted the width of 3 black modules,
+    // and 1 white and 1 black module on either side. Ergo, divide sum by 14.
+    return (moduleSizeEst1 + moduleSizeEst2) / 14.0f;
+  }
+
+  /**
+   * See {@link #sizeOfBlackWhiteBlackRun(int, int, int, int)}; computes the total width of
+   * a finder pattern by looking for a black-white-black run from the center in the direction
+   * of another point (another finder pattern center), and in the opposite direction too.</p>
+   */
+  private float sizeOfBlackWhiteBlackRunBothWays(int fromX, int fromY, int toX, int toY) {
+
+   float result = sizeOfBlackWhiteBlackRun(fromX, fromY, toX, toY);
+
+   // Now count other way -- don't run off image though of course
+   float scale = 1.0f;
+   int otherToX = fromX - (toX - fromX);
+   if (otherToX < 0) {
+     scale = (float) fromX / (float) (fromX - otherToX);
+     otherToX = 0;
+   } else if (otherToX > image.getWidth()) {
+     scale = (float) (image.getWidth() - fromX) / (float) (otherToX - fromX);
+     otherToX = image.getWidth();
+   }
+   int otherToY = (int) (fromY - (toY - fromY) * scale);
+
+   scale = 1.0f;
+   if (otherToY < 0) {
+     scale = (float) fromY / (float) (fromY - otherToY);
+     otherToY = 0;
+   } else if (otherToY > image.getHeight()) {
+     scale = (float) (image.getHeight() - fromY) / (float) (otherToY - fromY);
+     otherToY = image.getHeight();
+   }
+   otherToX = (int) (fromX + (otherToX - fromX) * scale);
+
+   result += sizeOfBlackWhiteBlackRun(fromX, fromY, otherToX, otherToY);
+   return result;
+ }
+
+  /**
+   * <p>This method traces a line from a point in the image, in the direction towards another point.
+   * It begins in a black region, and keeps going until it finds white, then black, then white again.
+   * It reports the distance from the start to this point.</p>
+   *
+   * <p>This is used when figuring out how wide a finder pattern is, when the finder pattern
+   * may be skewed or rotated.</p>
+   */
+  private float sizeOfBlackWhiteBlackRun(int fromX, int fromY, int toX, int toY) {
+    // Mild variant of Bresenham's algorithm;
+    // see http://en.wikipedia.org/wiki/Bresenham's_line_algorithm
+    boolean steep = Math.abs(toY - fromY) > Math.abs(toX - fromX);
+    if (steep) {
+      int temp = fromX;
+      fromX = fromY;
+      fromY = temp;
+      temp = toX;
+      toX = toY;
+      toY = temp;
+    }
+
+    int dx = Math.abs(toX - fromX);
+    int dy = Math.abs(toY - fromY);
+    int error = -dx >> 1;
+    int xstep = fromX < toX ? 1 : -1;
+    int ystep = fromY < toY ? 1 : -1;
+
+    // In black pixels, looking for white, first or second time.
+    int state = 0;
+    for (int x = fromX, y = fromY; x != toX; x += xstep) {
+      int realX = steep ? y : x;
+      int realY = steep ? x : y;
+
+      // In white pixels, looking for black.
+      // FIXME(dswitkin): This method seems to assume square images, which can cause these calls to
+      // BitMatrix.get() to throw ArrayIndexOutOfBoundsException.
+      if (state == 1) {
+        if (image.get(realX, realY)) {
+          state++;
+        }
+      } else {
+        if (!image.get(realX, realY)) {
+          state++;
+        }
+      }
+
+      // Found black, white, black, and stumbled back onto white, so we're done.
+      if (state == 3) {
+        int diffX = x - fromX;
+        int diffY = y - fromY;
+        if (xstep < 0) {
+            diffX++;
+        }
+        return (float) Math.sqrt((double) (diffX * diffX + diffY * diffY));
+      }
+      error += dy;
+      if (error > 0) {
+        if (y == toY) {
+          break;
+        }
+        y += ystep;
+        error -= dx;
+      }
+    }
+    int diffX = toX - fromX;
+    int diffY = toY - fromY;
+    return (float) Math.sqrt((double) (diffX * diffX + diffY * diffY));
+  }
+
+  /**
+   * <p>Attempts to locate an alignment pattern in a limited region of the image, which is
+   * guessed to contain it. This method uses {@link AlignmentPattern}.</p>
+   *
+   * @param overallEstModuleSize estimated module size so far
+   * @param estAlignmentX x coordinate of center of area probably containing alignment pattern
+   * @param estAlignmentY y coordinate of above
+   * @param allowanceFactor number of pixels in all directions to search from the center
+   * @return {@link AlignmentPattern} if found, or null otherwise
+   * @throws NotFoundException if an unexpected error occurs during detection
+   */
+  protected AlignmentPattern findAlignmentInRegion(float overallEstModuleSize,
+                                                   int estAlignmentX,
+                                                   int estAlignmentY,
+                                                   float allowanceFactor)
+      throws NotFoundException {
+    // Look for an alignment pattern (3 modules in size) around where it
+    // should be
+    int allowance = (int) (allowanceFactor * overallEstModuleSize);
+    int alignmentAreaLeftX = Math.max(0, estAlignmentX - allowance);
+    int alignmentAreaRightX = Math.min(image.getWidth() - 1, estAlignmentX + allowance);
+    if (alignmentAreaRightX - alignmentAreaLeftX < overallEstModuleSize * 3) {
+      throw NotFoundException.getNotFoundInstance();
+    }
+
+    int alignmentAreaTopY = Math.max(0, estAlignmentY - allowance);
+    int alignmentAreaBottomY = Math.min(image.getHeight() - 1, estAlignmentY + allowance);
+    if (alignmentAreaBottomY - alignmentAreaTopY < overallEstModuleSize * 3) {
+      throw NotFoundException.getNotFoundInstance();
+    }
+
+    AlignmentPatternFinder alignmentFinder =
+        new AlignmentPatternFinder(
+            image,
+            alignmentAreaLeftX,
+            alignmentAreaTopY,
+            alignmentAreaRightX - alignmentAreaLeftX,
+            alignmentAreaBottomY - alignmentAreaTopY,
+            overallEstModuleSize,
+            resultPointCallback);
+    return alignmentFinder.find();
+  }
+
+  /**
+   * Ends up being a bit faster than Math.round(). This merely rounds its argument to the nearest int,
+   * where x.5 rounds up.
+   */
+  private static int round(float d) {
+    return (int) (d + 0.5f);
+  }
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/detector/FinderPattern.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.detector;
+
+import com.google.zxing.ResultPoint;
+
+/**
+ * <p>Encapsulates a finder pattern, which are the three square patterns found in
+ * the corners of QR Codes. It also encapsulates a count of similar finder patterns,
+ * as a convenience to the finder's bookkeeping.</p>
+ *
+ * @author Sean Owen
+ */
+public final class FinderPattern extends ResultPoint {
+
+  private final float estimatedModuleSize;
+  private int count;
+
+  FinderPattern(float posX, float posY, float estimatedModuleSize) {
+    super(posX, posY);
+    this.estimatedModuleSize = estimatedModuleSize;
+    this.count = 1;
+  }
+
+  public float getEstimatedModuleSize() {
+    return estimatedModuleSize;
+  }
+
+  int getCount() {
+    return count;
+  }
+
+  void incrementCount() {
+    this.count++;
+  }
+
+  /**
+   * <p>Determines if this finder pattern "about equals" a finder pattern at the stated
+   * position and size -- meaning, it is at nearly the same center with nearly the same size.</p>
+   */
+  boolean aboutEquals(float moduleSize, float i, float j) {
+    if (Math.abs(i - getY()) <= moduleSize && Math.abs(j - getX()) <= moduleSize) {
+      float moduleSizeDiff = Math.abs(moduleSize - estimatedModuleSize);
+      return moduleSizeDiff <= 1.0f || moduleSizeDiff / estimatedModuleSize <= 1.0f;
+    }
+    return false;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/detector/FinderPatternFinder.java

@@ -0,0 +1,585 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.detector;
+
+import com.google.zxing.DecodeHintType;
+import com.google.zxing.NotFoundException;
+import com.google.zxing.ResultPoint;
+import com.google.zxing.ResultPointCallback;
+import com.google.zxing.common.BitMatrix;
+import com.google.zxing.common.Collections;
+import com.google.zxing.common.Comparator;
+
+import java.util.Hashtable;
+import java.util.Vector;
+
+/**
+ * <p>This class attempts to find finder patterns in a QR Code. Finder patterns are the square
+ * markers at three corners of a QR Code.</p>
+ *
+ * <p>This class is thread-safe but not reentrant. Each thread must allocate its own object.
+ *
+ * @author Sean Owen
+ */
+public class FinderPatternFinder {
+
+  private static final int CENTER_QUORUM = 2;
+  protected static final int MIN_SKIP = 3; // 1 pixel/module times 3 modules/center
+  protected static final int MAX_MODULES = 57; // support up to version 10 for mobile clients
+  private static final int INTEGER_MATH_SHIFT = 8;
+
+  private final BitMatrix image;
+  private final Vector possibleCenters;
+  private boolean hasSkipped;
+  private final int[] crossCheckStateCount;
+  private final ResultPointCallback resultPointCallback;
+
+  /**
+   * <p>Creates a finder that will search the image for three finder patterns.</p>
+   *
+   * @param image image to search
+   */
+  public FinderPatternFinder(BitMatrix image) {
+    this(image, null);
+  }
+
+  public FinderPatternFinder(BitMatrix image, ResultPointCallback resultPointCallback) {
+    this.image = image;
+    this.possibleCenters = new Vector();
+    this.crossCheckStateCount = new int[5];
+    this.resultPointCallback = resultPointCallback;
+  }
+
+  protected BitMatrix getImage() {
+    return image;
+  }
+
+  protected Vector getPossibleCenters() {
+    return possibleCenters;
+  }
+
+  FinderPatternInfo find(Hashtable hints) throws NotFoundException {
+    boolean tryHarder = hints != null && hints.containsKey(DecodeHintType.TRY_HARDER);
+    int maxI = image.getHeight();
+    int maxJ = image.getWidth();
+    // We are looking for black/white/black/white/black modules in
+    // 1:1:3:1:1 ratio; this tracks the number of such modules seen so far
+
+    // Let's assume that the maximum version QR Code we support takes up 1/4 the height of the
+    // image, and then account for the center being 3 modules in size. This gives the smallest
+    // number of pixels the center could be, so skip this often. When trying harder, look for all
+    // QR versions regardless of how dense they are.
+    int iSkip = (3 * maxI) / (4 * MAX_MODULES);
+    if (iSkip < MIN_SKIP || tryHarder) {
+      iSkip = MIN_SKIP;
+    }
+
+    boolean done = false;
+    int[] stateCount = new int[5];
+    for (int i = iSkip - 1; i < maxI && !done; i += iSkip) {
+      // Get a row of black/white values
+      stateCount[0] = 0;
+      stateCount[1] = 0;
+      stateCount[2] = 0;
+      stateCount[3] = 0;
+      stateCount[4] = 0;
+      int currentState = 0;
+      for (int j = 0; j < maxJ; j++) {
+        if (image.get(j, i)) {
+          // Black pixel
+          if ((currentState & 1) == 1) { // Counting white pixels
+            currentState++;
+          }
+          stateCount[currentState]++;
+        } else { // White pixel
+          if ((currentState & 1) == 0) { // Counting black pixels
+            if (currentState == 4) { // A winner?
+              if (foundPatternCross(stateCount)) { // Yes
+                boolean confirmed = handlePossibleCenter(stateCount, i, j);
+                if (confirmed) {
+                  // Start examining every other line. Checking each line turned out to be too
+                  // expensive and didn't improve performance.
+                  iSkip = 2;
+                  if (hasSkipped) {
+                    done = haveMultiplyConfirmedCenters();
+                  } else {
+                    int rowSkip = findRowSkip();
+                    if (rowSkip > stateCount[2]) {
+                      // Skip rows between row of lower confirmed center
+                      // and top of presumed third confirmed center
+                      // but back up a bit to get a full chance of detecting
+                      // it, entire width of center of finder pattern
+
+                      // Skip by rowSkip, but back off by stateCount[2] (size of last center
+                      // of pattern we saw) to be conservative, and also back off by iSkip which
+                      // is about to be re-added
+                      i += rowSkip - stateCount[2] - iSkip;
+                      j = maxJ - 1;
+                    }
+                  }
+                } else {
+                  stateCount[0] = stateCount[2];
+                  stateCount[1] = stateCount[3];
+                  stateCount[2] = stateCount[4];
+                  stateCount[3] = 1;
+                  stateCount[4] = 0;
+                  currentState = 3;
+                  continue;
+                }
+                // Clear state to start looking again
+                currentState = 0;
+                stateCount[0] = 0;
+                stateCount[1] = 0;
+                stateCount[2] = 0;
+                stateCount[3] = 0;
+                stateCount[4] = 0;
+              } else { // No, shift counts back by two
+                stateCount[0] = stateCount[2];
+                stateCount[1] = stateCount[3];
+                stateCount[2] = stateCount[4];
+                stateCount[3] = 1;
+                stateCount[4] = 0;
+                currentState = 3;
+              }
+            } else {
+              stateCount[++currentState]++;
+            }
+          } else { // Counting white pixels
+            stateCount[currentState]++;
+          }
+        }
+      }
+      if (foundPatternCross(stateCount)) {
+        boolean confirmed = handlePossibleCenter(stateCount, i, maxJ);
+        if (confirmed) {
+          iSkip = stateCount[0];
+          if (hasSkipped) {
+            // Found a third one
+            done = haveMultiplyConfirmedCenters();
+          }
+        }
+      }
+    }
+
+    FinderPattern[] patternInfo = selectBestPatterns();
+    ResultPoint.orderBestPatterns(patternInfo);
+
+    return new FinderPatternInfo(patternInfo);
+  }
+
+  /**
+   * Given a count of black/white/black/white/black pixels just seen and an end position,
+   * figures the location of the center of this run.
+   */
+  private static float centerFromEnd(int[] stateCount, int end) {
+    return (float) (end - stateCount[4] - stateCount[3]) - stateCount[2] / 2.0f;
+  }
+
+  /**
+   * @param stateCount count of black/white/black/white/black pixels just read
+   * @return true iff the proportions of the counts is close enough to the 1/1/3/1/1 ratios
+   *         used by finder patterns to be considered a match
+   */
+  protected static boolean foundPatternCross(int[] stateCount) {
+    int totalModuleSize = 0;
+    for (int i = 0; i < 5; i++) {
+      int count = stateCount[i];
+      if (count == 0) {
+        return false;
+      }
+      totalModuleSize += count;
+    }
+    if (totalModuleSize < 7) {
+      return false;
+    }
+    int moduleSize = (totalModuleSize << INTEGER_MATH_SHIFT) / 7;
+    int maxVariance = moduleSize / 2;
+    // Allow less than 50% variance from 1-1-3-1-1 proportions
+    return Math.abs(moduleSize - (stateCount[0] << INTEGER_MATH_SHIFT)) < maxVariance &&
+        Math.abs(moduleSize - (stateCount[1] << INTEGER_MATH_SHIFT)) < maxVariance &&
+        Math.abs(3 * moduleSize - (stateCount[2] << INTEGER_MATH_SHIFT)) < 3 * maxVariance &&
+        Math.abs(moduleSize - (stateCount[3] << INTEGER_MATH_SHIFT)) < maxVariance &&
+        Math.abs(moduleSize - (stateCount[4] << INTEGER_MATH_SHIFT)) < maxVariance;
+  }
+
+  private int[] getCrossCheckStateCount() {
+    crossCheckStateCount[0] = 0;
+    crossCheckStateCount[1] = 0;
+    crossCheckStateCount[2] = 0;
+    crossCheckStateCount[3] = 0;
+    crossCheckStateCount[4] = 0;
+    return crossCheckStateCount;
+  }
+
+  /**
+   * <p>After a horizontal scan finds a potential finder pattern, this method
+   * "cross-checks" by scanning down vertically through the center of the possible
+   * finder pattern to see if the same proportion is detected.</p>
+   *
+   * @param startI row where a finder pattern was detected
+   * @param centerJ center of the section that appears to cross a finder pattern
+   * @param maxCount maximum reasonable number of modules that should be
+   * observed in any reading state, based on the results of the horizontal scan
+   * @return vertical center of finder pattern, or {@link Float#NaN} if not found
+   */
+  private float crossCheckVertical(int startI, int centerJ, int maxCount,
+      int originalStateCountTotal) {
+    BitMatrix image = this.image;
+
+    int maxI = image.getHeight();
+    int[] stateCount = getCrossCheckStateCount();
+
+    // Start counting up from center
+    int i = startI;
+    while (i >= 0 && image.get(centerJ, i)) {
+      stateCount[2]++;
+      i--;
+    }
+    if (i < 0) {
+      return Float.NaN;
+    }
+    while (i >= 0 && !image.get(centerJ, i) && stateCount[1] <= maxCount) {
+      stateCount[1]++;
+      i--;
+    }
+    // If already too many modules in this state or ran off the edge:
+    if (i < 0 || stateCount[1] > maxCount) {
+      return Float.NaN;
+    }
+    while (i >= 0 && image.get(centerJ, i) && stateCount[0] <= maxCount) {
+      stateCount[0]++;
+      i--;
+    }
+    if (stateCount[0] > maxCount) {
+      return Float.NaN;
+    }
+
+    // Now also count down from center
+    i = startI + 1;
+    while (i < maxI && image.get(centerJ, i)) {
+      stateCount[2]++;
+      i++;
+    }
+    if (i == maxI) {
+      return Float.NaN;
+    }
+    while (i < maxI && !image.get(centerJ, i) && stateCount[3] < maxCount) {
+      stateCount[3]++;
+      i++;
+    }
+    if (i == maxI || stateCount[3] >= maxCount) {
+      return Float.NaN;
+    }
+    while (i < maxI && image.get(centerJ, i) && stateCount[4] < maxCount) {
+      stateCount[4]++;
+      i++;
+    }
+    if (stateCount[4] >= maxCount) {
+      return Float.NaN;
+    }
+
+    // If we found a finder-pattern-like section, but its size is more than 40% different than
+    // the original, assume it's a false positive
+    int stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2] + stateCount[3] +
+        stateCount[4];
+    if (5 * Math.abs(stateCountTotal - originalStateCountTotal) >= 2 * originalStateCountTotal) {
+      return Float.NaN;
+    }
+
+    return foundPatternCross(stateCount) ? centerFromEnd(stateCount, i) : Float.NaN;
+  }
+
+  /**
+   * <p>Like {@link #crossCheckVertical(int, int, int, int)}, and in fact is basically identical,
+   * except it reads horizontally instead of vertically. This is used to cross-cross
+   * check a vertical cross check and locate the real center of the alignment pattern.</p>
+   */
+  private float crossCheckHorizontal(int startJ, int centerI, int maxCount,
+      int originalStateCountTotal) {
+    BitMatrix image = this.image;
+
+    int maxJ = image.getWidth();
+    int[] stateCount = getCrossCheckStateCount();
+
+    int j = startJ;
+    while (j >= 0 && image.get(j, centerI)) {
+      stateCount[2]++;
+      j--;
+    }
+    if (j < 0) {
+      return Float.NaN;
+    }
+    while (j >= 0 && !image.get(j, centerI) && stateCount[1] <= maxCount) {
+      stateCount[1]++;
+      j--;
+    }
+    if (j < 0 || stateCount[1] > maxCount) {
+      return Float.NaN;
+    }
+    while (j >= 0 && image.get(j, centerI) && stateCount[0] <= maxCount) {
+      stateCount[0]++;
+      j--;
+    }
+    if (stateCount[0] > maxCount) {
+      return Float.NaN;
+    }
+
+    j = startJ + 1;
+    while (j < maxJ && image.get(j, centerI)) {
+      stateCount[2]++;
+      j++;
+    }
+    if (j == maxJ) {
+      return Float.NaN;
+    }
+    while (j < maxJ && !image.get(j, centerI) && stateCount[3] < maxCount) {
+      stateCount[3]++;
+      j++;
+    }
+    if (j == maxJ || stateCount[3] >= maxCount) {
+      return Float.NaN;
+    }
+    while (j < maxJ && image.get(j, centerI) && stateCount[4] < maxCount) {
+      stateCount[4]++;
+      j++;
+    }
+    if (stateCount[4] >= maxCount) {
+      return Float.NaN;
+    }
+
+    // If we found a finder-pattern-like section, but its size is significantly different than
+    // the original, assume it's a false positive
+    int stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2] + stateCount[3] +
+        stateCount[4];
+    if (5 * Math.abs(stateCountTotal - originalStateCountTotal) >= originalStateCountTotal) {
+      return Float.NaN;
+    }
+
+    return foundPatternCross(stateCount) ? centerFromEnd(stateCount, j) : Float.NaN;
+  }
+
+  /**
+   * <p>This is called when a horizontal scan finds a possible alignment pattern. It will
+   * cross check with a vertical scan, and if successful, will, ah, cross-cross-check
+   * with another horizontal scan. This is needed primarily to locate the real horizontal
+   * center of the pattern in cases of extreme skew.</p>
+   *
+   * <p>If that succeeds the finder pattern location is added to a list that tracks
+   * the number of times each location has been nearly-matched as a finder pattern.
+   * Each additional find is more evidence that the location is in fact a finder
+   * pattern center
+   *
+   * @param stateCount reading state module counts from horizontal scan
+   * @param i row where finder pattern may be found
+   * @param j end of possible finder pattern in row
+   * @return true if a finder pattern candidate was found this time
+   */
+  protected boolean handlePossibleCenter(int[] stateCount, int i, int j) {
+    int stateCountTotal = stateCount[0] + stateCount[1] + stateCount[2] + stateCount[3] +
+        stateCount[4];
+    float centerJ = centerFromEnd(stateCount, j);
+    float centerI = crossCheckVertical(i, (int) centerJ, stateCount[2], stateCountTotal);
+    if (!Float.isNaN(centerI)) {
+      // Re-cross check
+      centerJ = crossCheckHorizontal((int) centerJ, (int) centerI, stateCount[2], stateCountTotal);
+      if (!Float.isNaN(centerJ)) {
+        float estimatedModuleSize = (float) stateCountTotal / 7.0f;
+        boolean found = false;
+        int max = possibleCenters.size();
+        for (int index = 0; index < max; index++) {
+          FinderPattern center = (FinderPattern) possibleCenters.elementAt(index);
+          // Look for about the same center and module size:
+          if (center.aboutEquals(estimatedModuleSize, centerI, centerJ)) {
+            center.incrementCount();
+            found = true;
+            break;
+          }
+        }
+        if (!found) {
+          ResultPoint point = new FinderPattern(centerJ, centerI, estimatedModuleSize);
+          possibleCenters.addElement(point);
+          if (resultPointCallback != null) {
+            resultPointCallback.foundPossibleResultPoint(point);
+          }
+        }
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /**
+   * @return number of rows we could safely skip during scanning, based on the first
+   *         two finder patterns that have been located. In some cases their position will
+   *         allow us to infer that the third pattern must lie below a certain point farther
+   *         down in the image.
+   */
+  private int findRowSkip() {
+    int max = possibleCenters.size();
+    if (max <= 1) {
+      return 0;
+    }
+    FinderPattern firstConfirmedCenter = null;
+    for (int i = 0; i < max; i++) {
+      FinderPattern center = (FinderPattern) possibleCenters.elementAt(i);
+      if (center.getCount() >= CENTER_QUORUM) {
+        if (firstConfirmedCenter == null) {
+          firstConfirmedCenter = center;
+        } else {
+          // We have two confirmed centers
+          // How far down can we skip before resuming looking for the next
+          // pattern? In the worst case, only the difference between the
+          // difference in the x / y coordinates of the two centers.
+          // This is the case where you find top left last.
+          hasSkipped = true;
+          return (int) (Math.abs(firstConfirmedCenter.getX() - center.getX()) -
+              Math.abs(firstConfirmedCenter.getY() - center.getY())) / 2;
+        }
+      }
+    }
+    return 0;
+  }
+
+  /**
+   * @return true iff we have found at least 3 finder patterns that have been detected
+   *         at least {@link #CENTER_QUORUM} times each, and, the estimated module size of the
+   *         candidates is "pretty similar"
+   */
+  private boolean haveMultiplyConfirmedCenters() {
+    int confirmedCount = 0;
+    float totalModuleSize = 0.0f;
+    int max = possibleCenters.size();
+    for (int i = 0; i < max; i++) {
+      FinderPattern pattern = (FinderPattern) possibleCenters.elementAt(i);
+      if (pattern.getCount() >= CENTER_QUORUM) {
+        confirmedCount++;
+        totalModuleSize += pattern.getEstimatedModuleSize();
+      }
+    }
+    if (confirmedCount < 3) {
+      return false;
+    }
+    // OK, we have at least 3 confirmed centers, but, it's possible that one is a "false positive"
+    // and that we need to keep looking. We detect this by asking if the estimated module sizes
+    // vary too much. We arbitrarily say that when the total deviation from average exceeds
+    // 5% of the total module size estimates, it's too much.
+    float average = totalModuleSize / (float) max;
+    float totalDeviation = 0.0f;
+    for (int i = 0; i < max; i++) {
+      FinderPattern pattern = (FinderPattern) possibleCenters.elementAt(i);
+      totalDeviation += Math.abs(pattern.getEstimatedModuleSize() - average);
+    }
+    return totalDeviation <= 0.05f * totalModuleSize;
+  }
+
+  /**
+   * @return the 3 best {@link FinderPattern}s from our list of candidates. The "best" are
+   *         those that have been detected at least {@link #CENTER_QUORUM} times, and whose module
+   *         size differs from the average among those patterns the least
+   * @throws NotFoundException if 3 such finder patterns do not exist
+   */
+  private FinderPattern[] selectBestPatterns() throws NotFoundException {
+
+    int startSize = possibleCenters.size();
+    if (startSize < 3) {
+      // Couldn't find enough finder patterns
+      throw NotFoundException.getNotFoundInstance();
+    }
+
+    // Filter outlier possibilities whose module size is too different
+    if (startSize > 3) {
+      // But we can only afford to do so if we have at least 4 possibilities to choose from
+      float totalModuleSize = 0.0f;
+      float square = 0.0f;
+      for (int i = 0; i < startSize; i++) {
+        float size = ((FinderPattern) possibleCenters.elementAt(i)).getEstimatedModuleSize();
+        totalModuleSize += size;
+        square += size * size;
+      }
+      float average = totalModuleSize / (float) startSize;
+      float stdDev = (float) Math.sqrt(square / startSize - average * average);
+
+      Collections.insertionSort(possibleCenters, new FurthestFromAverageComparator(average));
+
+      float limit = Math.max(0.2f * average, stdDev);
+
+      for (int i = 0; i < possibleCenters.size() && possibleCenters.size() > 3; i++) {
+        FinderPattern pattern = (FinderPattern) possibleCenters.elementAt(i);
+        if (Math.abs(pattern.getEstimatedModuleSize() - average) > limit) {
+          possibleCenters.removeElementAt(i);
+          i--;
+        }
+      }
+    }
+
+    if (possibleCenters.size() > 3) {
+      // Throw away all but those first size candidate points we found.
+
+      float totalModuleSize = 0.0f;
+      for (int i = 0; i < possibleCenters.size(); i++) {
+        totalModuleSize += ((FinderPattern) possibleCenters.elementAt(i)).getEstimatedModuleSize();
+      }
+
+      float average = totalModuleSize / (float) possibleCenters.size();
+
+      Collections.insertionSort(possibleCenters, new CenterComparator(average));
+
+      possibleCenters.setSize(3);
+    }
+
+    return new FinderPattern[]{
+        (FinderPattern) possibleCenters.elementAt(0),
+        (FinderPattern) possibleCenters.elementAt(1),
+        (FinderPattern) possibleCenters.elementAt(2)
+    };
+  }
+
+  /**
+   * <p>Orders by furthest from average</p>
+   */
+  private static class FurthestFromAverageComparator implements Comparator {
+    private final float average;
+    private FurthestFromAverageComparator(float f) {
+      average = f;
+    }
+    public int compare(Object center1, Object center2) {
+      float dA = Math.abs(((FinderPattern) center2).getEstimatedModuleSize() - average);
+      float dB = Math.abs(((FinderPattern) center1).getEstimatedModuleSize() - average);
+      return dA < dB ? -1 : dA == dB ? 0 : 1;
+    }
+  }
+
+  /**
+   * <p>Orders by {@link FinderPattern#getCount()}, descending.</p>
+   */
+  private static class CenterComparator implements Comparator {
+    private final float average;
+    private CenterComparator(float f) {
+      average = f;
+    }
+    public int compare(Object center1, Object center2) {
+      if (((FinderPattern) center2).getCount() == ((FinderPattern) center1).getCount()) {
+        float dA = Math.abs(((FinderPattern) center2).getEstimatedModuleSize() - average);
+        float dB = Math.abs(((FinderPattern) center1).getEstimatedModuleSize() - average);
+        return dA < dB ? 1 : dA == dB ? 0 : -1;
+      } else {
+        return ((FinderPattern) center2).getCount() - ((FinderPattern) center1).getCount();
+      }
+    }
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/detector/FinderPatternInfo.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.detector;
+
+/**
+ * <p>Encapsulates information about finder patterns in an image, including the location of
+ * the three finder patterns, and their estimated module size.</p>
+ *
+ * @author Sean Owen
+ */
+public final class FinderPatternInfo {
+
+  private final FinderPattern bottomLeft;
+  private final FinderPattern topLeft;
+  private final FinderPattern topRight;
+
+  public FinderPatternInfo(FinderPattern[] patternCenters) {
+    this.bottomLeft = patternCenters[0];
+    this.topLeft = patternCenters[1];
+    this.topRight = patternCenters[2];
+  }
+
+  public FinderPattern getBottomLeft() {
+    return bottomLeft;
+  }
+
+  public FinderPattern getTopLeft() {
+    return topLeft;
+  }
+
+  public FinderPattern getTopRight() {
+    return topRight;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/BlockPair.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+final class BlockPair {
+
+  private final byte[] dataBytes;
+  private final byte[] errorCorrectionBytes;
+
+  BlockPair(byte[] data, byte[] errorCorrection) {
+    dataBytes = data;
+    errorCorrectionBytes = errorCorrection;
+  }
+
+  public byte[] getDataBytes() {
+    return dataBytes;
+  }
+
+  public byte[] getErrorCorrectionBytes() {
+    return errorCorrectionBytes;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/ByteMatrix.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+/**
+ * A class which wraps a 2D array of bytes. The default usage is signed. If you want to use it as a
+ * unsigned container, it's up to you to do byteValue & 0xff at each location.
+ *
+ * JAVAPORT: The original code was a 2D array of ints, but since it only ever gets assigned
+ * -1, 0, and 1, I'm going to use less memory and go with bytes.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public final class ByteMatrix {
+
+  private final byte[][] bytes;
+  private final int width;
+  private final int height;
+
+  public ByteMatrix(int width, int height) {
+    bytes = new byte[height][width];
+    this.width = width;
+    this.height = height;
+  }
+
+  public int getHeight() {
+    return height;
+  }
+
+  public int getWidth() {
+    return width;
+  }
+
+  public byte get(int x, int y) {
+    return bytes[y][x];
+  }
+
+  public byte[][] getArray() {
+    return bytes;
+  }
+
+  public void set(int x, int y, byte value) {
+    bytes[y][x] = value;
+  }
+
+  public void set(int x, int y, int value) {
+    bytes[y][x] = (byte) value;
+  }
+
+  public void set(int x, int y, boolean value) {
+    bytes[y][x] = (byte) (value ? 1 : 0);
+  }
+
+  public void clear(byte value) {
+    for (int y = 0; y < height; ++y) {
+      for (int x = 0; x < width; ++x) {
+        bytes[y][x] = value;
+      }
+    }
+  }
+
+  public String toString() {
+    StringBuffer result = new StringBuffer(2 * width * height + 2);
+    for (int y = 0; y < height; ++y) {
+      for (int x = 0; x < width; ++x) {
+        switch (bytes[y][x]) {
+          case 0:
+            result.append(" 0");
+            break;
+          case 1:
+            result.append(" 1");
+            break;
+          default:
+            result.append("  ");
+            break;
+        }
+      }
+      result.append('\n');
+    }
+    return result.toString();
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/Encoder.java

@@ -0,0 +1,557 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+import com.google.zxing.EncodeHintType;
+import com.google.zxing.WriterException;
+import com.google.zxing.common.BitArray;
+import com.google.zxing.common.CharacterSetECI;
+import com.google.zxing.common.ECI;
+import com.google.zxing.common.reedsolomon.GenericGF;
+import com.google.zxing.common.reedsolomon.ReedSolomonEncoder;
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+import com.google.zxing.qrcode.decoder.Mode;
+import com.google.zxing.qrcode.decoder.Version;
+
+import java.io.UnsupportedEncodingException;
+import java.util.Hashtable;
+import java.util.Vector;
+
+/**
+ * @author satorux@google.com (Satoru Takabayashi) - creator
+ * @author dswitkin@google.com (Daniel Switkin) - ported from C++
+ */
+public final class Encoder {
+
+  // The original table is defined in the table 5 of JISX0510:2004 (p.19).
+  private static final int[] ALPHANUMERIC_TABLE = {
+      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,  // 0x00-0x0f
+      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,  // 0x10-0x1f
+      36, -1, -1, -1, 37, 38, -1, -1, -1, -1, 39, 40, -1, 41, 42, 43,  // 0x20-0x2f
+      0,   1,  2,  3,  4,  5,  6,  7,  8,  9, 44, -1, -1, -1, -1, -1,  // 0x30-0x3f
+      -1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,  // 0x40-0x4f
+      25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, -1, -1, -1, -1, -1,  // 0x50-0x5f
+  };
+
+  static final String DEFAULT_BYTE_MODE_ENCODING = "ISO-8859-1";
+
+  private Encoder() {
+  }
+
+  // The mask penalty calculation is complicated.  See Table 21 of JISX0510:2004 (p.45) for details.
+  // Basically it applies four rules and summate all penalties.
+  private static int calculateMaskPenalty(ByteMatrix matrix) {
+    int penalty = 0;
+    penalty += MaskUtil.applyMaskPenaltyRule1(matrix);
+    penalty += MaskUtil.applyMaskPenaltyRule2(matrix);
+    penalty += MaskUtil.applyMaskPenaltyRule3(matrix);
+    penalty += MaskUtil.applyMaskPenaltyRule4(matrix);
+    return penalty;
+  }
+
+  /**
+   *  Encode "bytes" with the error correction level "ecLevel". The encoding mode will be chosen
+   * internally by chooseMode(). On success, store the result in "qrCode".
+   *
+   * We recommend you to use QRCode.EC_LEVEL_L (the lowest level) for
+   * "getECLevel" since our primary use is to show QR code on desktop screens. We don't need very
+   * strong error correction for this purpose.
+   *
+   * Note that there is no way to encode bytes in MODE_KANJI. We might want to add EncodeWithMode()
+   * with which clients can specify the encoding mode. For now, we don't need the functionality.
+   */
+  public static void encode(String content, ErrorCorrectionLevel ecLevel, QRCode qrCode)
+      throws WriterException {
+    encode(content, ecLevel, null, qrCode);
+  }
+
+  public static void encode(String content, ErrorCorrectionLevel ecLevel, Hashtable hints,
+      QRCode qrCode) throws WriterException {
+
+    String encoding = hints == null ? null : (String) hints.get(EncodeHintType.CHARACTER_SET);
+    if (encoding == null) {
+      encoding = DEFAULT_BYTE_MODE_ENCODING;
+    }
+
+    // Step 1: Choose the mode (encoding).
+    Mode mode = chooseMode(content, encoding);
+
+    // Step 2: Append "bytes" into "dataBits" in appropriate encoding.
+    BitArray dataBits = new BitArray();
+    appendBytes(content, mode, dataBits, encoding);
+    // Step 3: Initialize QR code that can contain "dataBits".
+    int numInputBytes = dataBits.getSizeInBytes();
+    initQRCode(numInputBytes, ecLevel, mode, qrCode);
+
+    // Step 4: Build another bit vector that contains header and data.
+    BitArray headerAndDataBits = new BitArray();
+
+    // Step 4.5: Append ECI message if applicable
+    if (mode == Mode.BYTE && !DEFAULT_BYTE_MODE_ENCODING.equals(encoding)) {
+      CharacterSetECI eci = CharacterSetECI.getCharacterSetECIByName(encoding);
+      if (eci != null) {
+        appendECI(eci, headerAndDataBits);
+      }
+    }
+
+    appendModeInfo(mode, headerAndDataBits);
+
+    int numLetters = mode.equals(Mode.BYTE) ? dataBits.getSizeInBytes() : content.length();
+    appendLengthInfo(numLetters, qrCode.getVersion(), mode, headerAndDataBits);
+    headerAndDataBits.appendBitArray(dataBits);
+
+    // Step 5: Terminate the bits properly.
+    terminateBits(qrCode.getNumDataBytes(), headerAndDataBits);
+
+    // Step 6: Interleave data bits with error correction code.
+    BitArray finalBits = new BitArray();
+    interleaveWithECBytes(headerAndDataBits, qrCode.getNumTotalBytes(), qrCode.getNumDataBytes(),
+        qrCode.getNumRSBlocks(), finalBits);
+
+    // Step 7: Choose the mask pattern and set to "qrCode".
+    ByteMatrix matrix = new ByteMatrix(qrCode.getMatrixWidth(), qrCode.getMatrixWidth());
+    qrCode.setMaskPattern(chooseMaskPattern(finalBits, qrCode.getECLevel(), qrCode.getVersion(),
+        matrix));
+
+    // Step 8.  Build the matrix and set it to "qrCode".
+    MatrixUtil.buildMatrix(finalBits, qrCode.getECLevel(), qrCode.getVersion(),
+        qrCode.getMaskPattern(), matrix);
+    qrCode.setMatrix(matrix);
+    // Step 9.  Make sure we have a valid QR Code.
+    if (!qrCode.isValid()) {
+      throw new WriterException("Invalid QR code: " + qrCode.toString());
+    }
+  }
+
+  /**
+   * @return the code point of the table used in alphanumeric mode or
+   *  -1 if there is no corresponding code in the table.
+   */
+  static int getAlphanumericCode(int code) {
+    if (code < ALPHANUMERIC_TABLE.length) {
+      return ALPHANUMERIC_TABLE[code];
+    }
+    return -1;
+  }
+
+  public static Mode chooseMode(String content) {
+    return chooseMode(content, null);
+  }
+
+  /**
+   * Choose the best mode by examining the content. Note that 'encoding' is used as a hint;
+   * if it is Shift_JIS, and the input is only double-byte Kanji, then we return {@link Mode#KANJI}.
+   */
+  public static Mode chooseMode(String content, String encoding) {
+    if ("Shift_JIS".equals(encoding)) {
+      // Choose Kanji mode if all input are double-byte characters
+      return isOnlyDoubleByteKanji(content) ? Mode.KANJI : Mode.BYTE;
+    }
+    boolean hasNumeric = false;
+    boolean hasAlphanumeric = false;
+    for (int i = 0; i < content.length(); ++i) {
+      char c = content.charAt(i);
+      if (c >= '0' && c <= '9') {
+        hasNumeric = true;
+      } else if (getAlphanumericCode(c) != -1) {
+        hasAlphanumeric = true;
+      } else {
+        return Mode.BYTE;
+      }
+    }
+    if (hasAlphanumeric) {
+      return Mode.ALPHANUMERIC;
+    } else if (hasNumeric) {
+      return Mode.NUMERIC;
+    }
+    return Mode.BYTE;
+  }
+
+  private static boolean isOnlyDoubleByteKanji(String content) {
+    byte[] bytes;
+    try {
+      bytes = content.getBytes("Shift_JIS");
+    } catch (UnsupportedEncodingException uee) {
+      return false;
+    }
+    int length = bytes.length;
+    if (length % 2 != 0) {
+      return false;
+    }
+    for (int i = 0; i < length; i += 2) {
+      int byte1 = bytes[i] & 0xFF;
+      if ((byte1 < 0x81 || byte1 > 0x9F) && (byte1 < 0xE0 || byte1 > 0xEB)) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  private static int chooseMaskPattern(BitArray bits, ErrorCorrectionLevel ecLevel, int version,
+      ByteMatrix matrix) throws WriterException {
+
+    int minPenalty = Integer.MAX_VALUE;  // Lower penalty is better.
+    int bestMaskPattern = -1;
+    // We try all mask patterns to choose the best one.
+    for (int maskPattern = 0; maskPattern < QRCode.NUM_MASK_PATTERNS; maskPattern++) {
+      MatrixUtil.buildMatrix(bits, ecLevel, version, maskPattern, matrix);
+      int penalty = calculateMaskPenalty(matrix);
+      if (penalty < minPenalty) {
+        minPenalty = penalty;
+        bestMaskPattern = maskPattern;
+      }
+    }
+    return bestMaskPattern;
+  }
+
+  /**
+   * Initialize "qrCode" according to "numInputBytes", "ecLevel", and "mode". On success,
+   * modify "qrCode".
+   */
+  private static void initQRCode(int numInputBytes, ErrorCorrectionLevel ecLevel, Mode mode,
+      QRCode qrCode) throws WriterException {
+    qrCode.setECLevel(ecLevel);
+    qrCode.setMode(mode);
+
+    // In the following comments, we use numbers of Version 7-H.
+    for (int versionNum = 1; versionNum <= 40; versionNum++) {
+      Version version = Version.getVersionForNumber(versionNum);
+      // numBytes = 196
+      int numBytes = version.getTotalCodewords();
+      // getNumECBytes = 130
+      Version.ECBlocks ecBlocks = version.getECBlocksForLevel(ecLevel);
+      int numEcBytes = ecBlocks.getTotalECCodewords();
+      // getNumRSBlocks = 5
+      int numRSBlocks = ecBlocks.getNumBlocks();
+      // getNumDataBytes = 196 - 130 = 66
+      int numDataBytes = numBytes - numEcBytes;
+      // We want to choose the smallest version which can contain data of "numInputBytes" + some
+      // extra bits for the header (mode info and length info). The header can be three bytes
+      // (precisely 4 + 16 bits) at most. Hence we do +3 here.
+      if (numDataBytes >= numInputBytes + 3) {
+        // Yay, we found the proper rs block info!
+        qrCode.setVersion(versionNum);
+        qrCode.setNumTotalBytes(numBytes);
+        qrCode.setNumDataBytes(numDataBytes);
+        qrCode.setNumRSBlocks(numRSBlocks);
+        // getNumECBytes = 196 - 66 = 130
+        qrCode.setNumECBytes(numEcBytes);
+        // matrix width = 21 + 6 * 4 = 45
+        qrCode.setMatrixWidth(version.getDimensionForVersion());
+        return;
+      }
+    }
+    throw new WriterException("Cannot find proper rs block info (input data too big?)");
+  }
+
+  /**
+   * Terminate bits as described in 8.4.8 and 8.4.9 of JISX0510:2004 (p.24).
+   */
+  static void terminateBits(int numDataBytes, BitArray bits) throws WriterException {
+    int capacity = numDataBytes << 3;
+    if (bits.getSize() > capacity) {
+      throw new WriterException("data bits cannot fit in the QR Code" + bits.getSize() + " > " +
+          capacity);
+    }
+    for (int i = 0; i < 4 && bits.getSize() < capacity; ++i) {
+      bits.appendBit(false);
+    }
+    // Append termination bits. See 8.4.8 of JISX0510:2004 (p.24) for details.
+    // If the last byte isn't 8-bit aligned, we'll add padding bits.
+    int numBitsInLastByte = bits.getSize() & 0x07;    
+    if (numBitsInLastByte > 0) {
+      for (int i = numBitsInLastByte; i < 8; i++) {
+        bits.appendBit(false);
+      }
+    }
+    // If we have more space, we'll fill the space with padding patterns defined in 8.4.9 (p.24).
+    int numPaddingBytes = numDataBytes - bits.getSizeInBytes();
+    for (int i = 0; i < numPaddingBytes; ++i) {
+      bits.appendBits((i & 0x01) == 0 ? 0xEC : 0x11, 8);
+    }
+    if (bits.getSize() != capacity) {
+      throw new WriterException("Bits size does not equal capacity");
+    }
+  }
+
+  /**
+   * Get number of data bytes and number of error correction bytes for block id "blockID". Store
+   * the result in "numDataBytesInBlock", and "numECBytesInBlock". See table 12 in 8.5.1 of
+   * JISX0510:2004 (p.30)
+   */
+  static void getNumDataBytesAndNumECBytesForBlockID(int numTotalBytes, int numDataBytes,
+      int numRSBlocks, int blockID, int[] numDataBytesInBlock,
+      int[] numECBytesInBlock) throws WriterException {
+    if (blockID >= numRSBlocks) {
+      throw new WriterException("Block ID too large");
+    }
+    // numRsBlocksInGroup2 = 196 % 5 = 1
+    int numRsBlocksInGroup2 = numTotalBytes % numRSBlocks;
+    // numRsBlocksInGroup1 = 5 - 1 = 4
+    int numRsBlocksInGroup1 = numRSBlocks - numRsBlocksInGroup2;
+    // numTotalBytesInGroup1 = 196 / 5 = 39
+    int numTotalBytesInGroup1 = numTotalBytes / numRSBlocks;
+    // numTotalBytesInGroup2 = 39 + 1 = 40
+    int numTotalBytesInGroup2 = numTotalBytesInGroup1 + 1;
+    // numDataBytesInGroup1 = 66 / 5 = 13
+    int numDataBytesInGroup1 = numDataBytes / numRSBlocks;
+    // numDataBytesInGroup2 = 13 + 1 = 14
+    int numDataBytesInGroup2 = numDataBytesInGroup1 + 1;
+    // numEcBytesInGroup1 = 39 - 13 = 26
+    int numEcBytesInGroup1 = numTotalBytesInGroup1 - numDataBytesInGroup1;
+    // numEcBytesInGroup2 = 40 - 14 = 26
+    int numEcBytesInGroup2 = numTotalBytesInGroup2 - numDataBytesInGroup2;
+    // Sanity checks.
+    // 26 = 26
+    if (numEcBytesInGroup1 != numEcBytesInGroup2) {
+      throw new WriterException("EC bytes mismatch");
+    }
+    // 5 = 4 + 1.
+    if (numRSBlocks != numRsBlocksInGroup1 + numRsBlocksInGroup2) {
+      throw new WriterException("RS blocks mismatch");
+    }
+    // 196 = (13 + 26) * 4 + (14 + 26) * 1
+    if (numTotalBytes !=
+        ((numDataBytesInGroup1 + numEcBytesInGroup1) *
+            numRsBlocksInGroup1) +
+            ((numDataBytesInGroup2 + numEcBytesInGroup2) *
+                numRsBlocksInGroup2)) {
+      throw new WriterException("Total bytes mismatch");
+    }
+
+    if (blockID < numRsBlocksInGroup1) {
+      numDataBytesInBlock[0] = numDataBytesInGroup1;
+      numECBytesInBlock[0] = numEcBytesInGroup1;
+    } else {
+      numDataBytesInBlock[0] = numDataBytesInGroup2;
+      numECBytesInBlock[0] = numEcBytesInGroup2;
+    }
+  }
+
+  /**
+   * Interleave "bits" with corresponding error correction bytes. On success, store the result in
+   * "result". The interleave rule is complicated. See 8.6 of JISX0510:2004 (p.37) for details.
+   */
+  static void interleaveWithECBytes(BitArray bits, int numTotalBytes,
+      int numDataBytes, int numRSBlocks, BitArray result) throws WriterException {
+
+    // "bits" must have "getNumDataBytes" bytes of data.
+    if (bits.getSizeInBytes() != numDataBytes) {
+      throw new WriterException("Number of bits and data bytes does not match");
+    }
+
+    // Step 1.  Divide data bytes into blocks and generate error correction bytes for them. We'll
+    // store the divided data bytes blocks and error correction bytes blocks into "blocks".
+    int dataBytesOffset = 0;
+    int maxNumDataBytes = 0;
+    int maxNumEcBytes = 0;
+
+    // Since, we know the number of reedsolmon blocks, we can initialize the vector with the number.
+    Vector blocks = new Vector(numRSBlocks);
+
+    for (int i = 0; i < numRSBlocks; ++i) {
+      int[] numDataBytesInBlock = new int[1];
+      int[] numEcBytesInBlock = new int[1];
+      getNumDataBytesAndNumECBytesForBlockID(
+          numTotalBytes, numDataBytes, numRSBlocks, i,
+          numDataBytesInBlock, numEcBytesInBlock);
+
+      int size = numDataBytesInBlock[0];
+      byte[] dataBytes = new byte[size];
+      bits.toBytes(8*dataBytesOffset, dataBytes, 0, size);
+      byte[] ecBytes = generateECBytes(dataBytes, numEcBytesInBlock[0]);
+      blocks.addElement(new BlockPair(dataBytes, ecBytes));
+
+      maxNumDataBytes = Math.max(maxNumDataBytes, size);
+      maxNumEcBytes = Math.max(maxNumEcBytes, ecBytes.length);
+      dataBytesOffset += numDataBytesInBlock[0];
+    }
+    if (numDataBytes != dataBytesOffset) {
+      throw new WriterException("Data bytes does not match offset");
+    }
+
+    // First, place data blocks.
+    for (int i = 0; i < maxNumDataBytes; ++i) {
+      for (int j = 0; j < blocks.size(); ++j) {
+        byte[] dataBytes = ((BlockPair) blocks.elementAt(j)).getDataBytes();
+        if (i < dataBytes.length) {
+          result.appendBits(dataBytes[i], 8);
+        }
+      }
+    }
+    // Then, place error correction blocks.
+    for (int i = 0; i < maxNumEcBytes; ++i) {
+      for (int j = 0; j < blocks.size(); ++j) {
+        byte[] ecBytes = ((BlockPair) blocks.elementAt(j)).getErrorCorrectionBytes();
+        if (i < ecBytes.length) {
+          result.appendBits(ecBytes[i], 8);
+        }
+      }
+    }
+    if (numTotalBytes != result.getSizeInBytes()) {  // Should be same.
+      throw new WriterException("Interleaving error: " + numTotalBytes + " and " +
+          result.getSizeInBytes() + " differ.");
+    }
+  }
+
+  static byte[] generateECBytes(byte[] dataBytes, int numEcBytesInBlock) {
+    int numDataBytes = dataBytes.length;
+    int[] toEncode = new int[numDataBytes + numEcBytesInBlock];
+    for (int i = 0; i < numDataBytes; i++) {
+      toEncode[i] = dataBytes[i] & 0xFF;
+    }
+    new ReedSolomonEncoder(GenericGF.QR_CODE_FIELD_256).encode(toEncode, numEcBytesInBlock);
+
+    byte[] ecBytes = new byte[numEcBytesInBlock];
+    for (int i = 0; i < numEcBytesInBlock; i++) {
+      ecBytes[i] = (byte) toEncode[numDataBytes + i];
+    }
+    return ecBytes;
+  }
+
+  /**
+   * Append mode info. On success, store the result in "bits".
+   */
+  static void appendModeInfo(Mode mode, BitArray bits) {
+    bits.appendBits(mode.getBits(), 4);
+  }
+
+
+  /**
+   * Append length info. On success, store the result in "bits".
+   */
+  static void appendLengthInfo(int numLetters, int version, Mode mode, BitArray bits)
+      throws WriterException {
+    int numBits = mode.getCharacterCountBits(Version.getVersionForNumber(version));
+    if (numLetters > ((1 << numBits) - 1)) {
+      throw new WriterException(numLetters + "is bigger than" + ((1 << numBits) - 1));
+    }
+    bits.appendBits(numLetters, numBits);
+  }
+
+  /**
+   * Append "bytes" in "mode" mode (encoding) into "bits". On success, store the result in "bits".
+   */
+  static void appendBytes(String content, Mode mode, BitArray bits, String encoding)
+      throws WriterException {
+    if (mode.equals(Mode.NUMERIC)) {
+      appendNumericBytes(content, bits);
+    } else if (mode.equals(Mode.ALPHANUMERIC)) {
+      appendAlphanumericBytes(content, bits);
+    } else if (mode.equals(Mode.BYTE)) {
+      append8BitBytes(content, bits, encoding);
+    } else if (mode.equals(Mode.KANJI)) {
+      appendKanjiBytes(content, bits);
+    } else {
+      throw new WriterException("Invalid mode: " + mode);
+    }
+  }
+
+  static void appendNumericBytes(String content, BitArray bits) {
+    int length = content.length();
+    int i = 0;
+    while (i < length) {
+      int num1 = content.charAt(i) - '0';
+      if (i + 2 < length) {
+        // Encode three numeric letters in ten bits.
+        int num2 = content.charAt(i + 1) - '0';
+        int num3 = content.charAt(i + 2) - '0';
+        bits.appendBits(num1 * 100 + num2 * 10 + num3, 10);
+        i += 3;
+      } else if (i + 1 < length) {
+        // Encode two numeric letters in seven bits.
+        int num2 = content.charAt(i + 1) - '0';
+        bits.appendBits(num1 * 10 + num2, 7);
+        i += 2;
+      } else {
+        // Encode one numeric letter in four bits.
+        bits.appendBits(num1, 4);
+        i++;
+      }
+    }
+  }
+
+  static void appendAlphanumericBytes(String content, BitArray bits) throws WriterException {
+    int length = content.length();
+    int i = 0;
+    while (i < length) {
+      int code1 = getAlphanumericCode(content.charAt(i));
+      if (code1 == -1) {
+        throw new WriterException();
+      }
+      if (i + 1 < length) {
+        int code2 = getAlphanumericCode(content.charAt(i + 1));
+        if (code2 == -1) {
+          throw new WriterException();
+        }
+        // Encode two alphanumeric letters in 11 bits.
+        bits.appendBits(code1 * 45 + code2, 11);
+        i += 2;
+      } else {
+        // Encode one alphanumeric letter in six bits.
+        bits.appendBits(code1, 6);
+        i++;
+      }
+    }
+  }
+
+  static void append8BitBytes(String content, BitArray bits, String encoding)
+      throws WriterException {
+    byte[] bytes;
+    try {
+      bytes = content.getBytes(encoding);
+    } catch (UnsupportedEncodingException uee) {
+      throw new WriterException(uee.toString());
+    }
+    for (int i = 0; i < bytes.length; ++i) {
+      bits.appendBits(bytes[i], 8);
+    }
+  }
+
+  static void appendKanjiBytes(String content, BitArray bits) throws WriterException {
+    byte[] bytes;
+    try {
+      bytes = content.getBytes("Shift_JIS");
+    } catch (UnsupportedEncodingException uee) {
+      throw new WriterException(uee.toString());
+    }
+    int length = bytes.length;
+    for (int i = 0; i < length; i += 2) {
+      int byte1 = bytes[i] & 0xFF;
+      int byte2 = bytes[i + 1] & 0xFF;
+      int code = (byte1 << 8) | byte2;
+      int subtracted = -1;
+      if (code >= 0x8140 && code <= 0x9ffc) {
+        subtracted = code - 0x8140;
+      } else if (code >= 0xe040 && code <= 0xebbf) {
+        subtracted = code - 0xc140;
+      }
+      if (subtracted == -1) {
+        throw new WriterException("Invalid byte sequence");
+      }
+      int encoded = ((subtracted >> 8) * 0xc0) + (subtracted & 0xff);
+      bits.appendBits(encoded, 13);
+    }
+  }
+
+  private static void appendECI(ECI eci, BitArray bits) {
+    bits.appendBits(Mode.ECI.getBits(), 4);
+    // This is correct for values up to 127, which is all we need now.
+    bits.appendBits(eci.getValue(), 8);
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/MaskUtil.java

@@ -0,0 +1,218 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+/**
+ * @author satorux@google.com (Satoru Takabayashi) - creator
+ * @author dswitkin@google.com (Daniel Switkin) - ported from C++
+ */
+public final class MaskUtil {
+
+  private MaskUtil() {
+    // do nothing
+  }
+
+  // Apply mask penalty rule 1 and return the penalty. Find repetitive cells with the same color and
+  // give penalty to them. Example: 00000 or 11111.
+  public static int applyMaskPenaltyRule1(ByteMatrix matrix) {
+    return applyMaskPenaltyRule1Internal(matrix, true) + applyMaskPenaltyRule1Internal(matrix, false);
+  }
+
+  // Apply mask penalty rule 2 and return the penalty. Find 2x2 blocks with the same color and give
+  // penalty to them.
+  public static int applyMaskPenaltyRule2(ByteMatrix matrix) {
+    int penalty = 0;
+    byte[][] array = matrix.getArray();
+    int width = matrix.getWidth();
+    int height = matrix.getHeight();
+    for (int y = 0; y < height - 1; ++y) {
+      for (int x = 0; x < width - 1; ++x) {
+        int value = array[y][x];
+        if (value == array[y][x + 1] && value == array[y + 1][x] && value == array[y + 1][x + 1]) {
+          penalty += 3;
+        }
+      }
+    }
+    return penalty;
+  }
+
+  // Apply mask penalty rule 3 and return the penalty. Find consecutive cells of 00001011101 or
+  // 10111010000, and give penalty to them.  If we find patterns like 000010111010000, we give
+  // penalties twice (i.e. 40 * 2).
+  public static int applyMaskPenaltyRule3(ByteMatrix matrix) {
+    int penalty = 0;
+    byte[][] array = matrix.getArray();
+    int width = matrix.getWidth();
+    int height = matrix.getHeight();
+    for (int y = 0; y < height; ++y) {
+      for (int x = 0; x < width; ++x) {
+        // Tried to simplify following conditions but failed.
+        if (x + 6 < width &&
+            array[y][x] == 1 &&
+            array[y][x +  1] == 0 &&
+            array[y][x +  2] == 1 &&
+            array[y][x +  3] == 1 &&
+            array[y][x +  4] == 1 &&
+            array[y][x +  5] == 0 &&
+            array[y][x +  6] == 1 &&
+            ((x + 10 < width &&
+                array[y][x +  7] == 0 &&
+                array[y][x +  8] == 0 &&
+                array[y][x +  9] == 0 &&
+                array[y][x + 10] == 0) ||
+                (x - 4 >= 0 &&
+                    array[y][x -  1] == 0 &&
+                    array[y][x -  2] == 0 &&
+                    array[y][x -  3] == 0 &&
+                    array[y][x -  4] == 0))) {
+          penalty += 40;
+        }
+        if (y + 6 < height &&
+            array[y][x] == 1  &&
+            array[y +  1][x] == 0  &&
+            array[y +  2][x] == 1  &&
+            array[y +  3][x] == 1  &&
+            array[y +  4][x] == 1  &&
+            array[y +  5][x] == 0  &&
+            array[y +  6][x] == 1 &&
+            ((y + 10 < height &&
+                array[y +  7][x] == 0 &&
+                array[y +  8][x] == 0 &&
+                array[y +  9][x] == 0 &&
+                array[y + 10][x] == 0) ||
+                (y - 4 >= 0 &&
+                    array[y -  1][x] == 0 &&
+                    array[y -  2][x] == 0 &&
+                    array[y -  3][x] == 0 &&
+                    array[y -  4][x] == 0))) {
+          penalty += 40;
+        }
+      }
+    }
+    return penalty;
+  }
+
+  // Apply mask penalty rule 4 and return the penalty. Calculate the ratio of dark cells and give
+  // penalty if the ratio is far from 50%. It gives 10 penalty for 5% distance. Examples:
+  // -   0% => 100
+  // -  40% =>  20
+  // -  45% =>  10
+  // -  50% =>   0
+  // -  55% =>  10
+  // -  55% =>  20
+  // - 100% => 100
+  public static int applyMaskPenaltyRule4(ByteMatrix matrix) {
+    int numDarkCells = 0;
+    byte[][] array = matrix.getArray();
+    int width = matrix.getWidth();
+    int height = matrix.getHeight();
+    for (int y = 0; y < height; ++y) {
+      for (int x = 0; x < width; ++x) {
+        if (array[y][x] == 1) {
+          numDarkCells += 1;
+        }
+      }
+    }
+    int numTotalCells = matrix.getHeight() * matrix.getWidth();
+    double darkRatio = (double) numDarkCells / numTotalCells;
+    return Math.abs((int) (darkRatio * 100 - 50)) / 5 * 10;
+  }
+
+  // Return the mask bit for "getMaskPattern" at "x" and "y". See 8.8 of JISX0510:2004 for mask
+  // pattern conditions.
+  public static boolean getDataMaskBit(int maskPattern, int x, int y) {
+    if (!QRCode.isValidMaskPattern(maskPattern)) {
+      throw new IllegalArgumentException("Invalid mask pattern");
+    }
+    int intermediate;
+    int temp;
+    switch (maskPattern) {
+      case 0:
+        intermediate = (y + x) & 0x1;
+        break;
+      case 1:
+        intermediate = y & 0x1;
+        break;
+      case 2:
+        intermediate = x % 3;
+        break;
+      case 3:
+        intermediate = (y + x) % 3;
+        break;
+      case 4:
+        intermediate = ((y >>> 1) + (x / 3)) & 0x1;
+        break;
+      case 5:
+        temp = y * x;
+        intermediate = (temp & 0x1) + (temp % 3);
+        break;
+      case 6:
+        temp = y * x;
+        intermediate = ((temp & 0x1) + (temp % 3)) & 0x1;
+        break;
+      case 7:
+        temp = y * x;
+        intermediate = ((temp % 3) + ((y + x) & 0x1)) & 0x1;
+        break;
+      default:
+        throw new IllegalArgumentException("Invalid mask pattern: " + maskPattern);
+    }
+    return intermediate == 0;
+  }
+
+  // Helper function for applyMaskPenaltyRule1. We need this for doing this calculation in both
+  // vertical and horizontal orders respectively.
+  private static int applyMaskPenaltyRule1Internal(ByteMatrix matrix, boolean isHorizontal) {
+    int penalty = 0;
+    int numSameBitCells = 0;
+    int prevBit = -1;
+    // Horizontal mode:
+    //   for (int i = 0; i < matrix.height(); ++i) {
+    //     for (int j = 0; j < matrix.width(); ++j) {
+    //       int bit = matrix.get(i, j);
+    // Vertical mode:
+    //   for (int i = 0; i < matrix.width(); ++i) {
+    //     for (int j = 0; j < matrix.height(); ++j) {
+    //       int bit = matrix.get(j, i);
+    int iLimit = isHorizontal ? matrix.getHeight() : matrix.getWidth();
+    int jLimit = isHorizontal ? matrix.getWidth() : matrix.getHeight();
+    byte[][] array = matrix.getArray();
+    for (int i = 0; i < iLimit; ++i) {
+      for (int j = 0; j < jLimit; ++j) {
+        int bit = isHorizontal ? array[i][j] : array[j][i];
+        if (bit == prevBit) {
+          numSameBitCells += 1;
+          // Found five repetitive cells with the same color (bit).
+          // We'll give penalty of 3.
+          if (numSameBitCells == 5) {
+            penalty += 3;
+          } else if (numSameBitCells > 5) {
+            // After five repetitive cells, we'll add the penalty one
+            // by one.
+            penalty += 1;
+          }
+        } else {
+          numSameBitCells = 1;  // Include the cell itself.
+          prevBit = bit;
+        }
+      }
+      numSameBitCells = 0;  // Clear at each row/column.
+    }
+    return penalty;
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/MatrixUtil.java

@@ -0,0 +1,524 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+import com.google.zxing.WriterException;
+import com.google.zxing.common.BitArray;
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+
+/**
+ * @author satorux@google.com (Satoru Takabayashi) - creator
+ * @author dswitkin@google.com (Daniel Switkin) - ported from C++
+ */
+public final class MatrixUtil {
+
+  private MatrixUtil() {
+    // do nothing
+  }
+
+  private static final int[][] POSITION_DETECTION_PATTERN =  {
+      {1, 1, 1, 1, 1, 1, 1},
+      {1, 0, 0, 0, 0, 0, 1},
+      {1, 0, 1, 1, 1, 0, 1},
+      {1, 0, 1, 1, 1, 0, 1},
+      {1, 0, 1, 1, 1, 0, 1},
+      {1, 0, 0, 0, 0, 0, 1},
+      {1, 1, 1, 1, 1, 1, 1},
+  };
+
+  private static final int[][] HORIZONTAL_SEPARATION_PATTERN = {
+      {0, 0, 0, 0, 0, 0, 0, 0},
+  };
+
+  private static final int[][] VERTICAL_SEPARATION_PATTERN = {
+      {0}, {0}, {0}, {0}, {0}, {0}, {0},
+  };
+
+  private static final int[][] POSITION_ADJUSTMENT_PATTERN = {
+      {1, 1, 1, 1, 1},
+      {1, 0, 0, 0, 1},
+      {1, 0, 1, 0, 1},
+      {1, 0, 0, 0, 1},
+      {1, 1, 1, 1, 1},
+  };
+
+  // From Appendix E. Table 1, JIS0510X:2004 (p 71). The table was double-checked by komatsu.
+  private static final int[][] POSITION_ADJUSTMENT_PATTERN_COORDINATE_TABLE = {
+      {-1, -1, -1, -1,  -1,  -1,  -1},  // Version 1
+      { 6, 18, -1, -1,  -1,  -1,  -1},  // Version 2
+      { 6, 22, -1, -1,  -1,  -1,  -1},  // Version 3
+      { 6, 26, -1, -1,  -1,  -1,  -1},  // Version 4
+      { 6, 30, -1, -1,  -1,  -1,  -1},  // Version 5
+      { 6, 34, -1, -1,  -1,  -1,  -1},  // Version 6
+      { 6, 22, 38, -1,  -1,  -1,  -1},  // Version 7
+      { 6, 24, 42, -1,  -1,  -1,  -1},  // Version 8
+      { 6, 26, 46, -1,  -1,  -1,  -1},  // Version 9
+      { 6, 28, 50, -1,  -1,  -1,  -1},  // Version 10
+      { 6, 30, 54, -1,  -1,  -1,  -1},  // Version 11
+      { 6, 32, 58, -1,  -1,  -1,  -1},  // Version 12
+      { 6, 34, 62, -1,  -1,  -1,  -1},  // Version 13
+      { 6, 26, 46, 66,  -1,  -1,  -1},  // Version 14
+      { 6, 26, 48, 70,  -1,  -1,  -1},  // Version 15
+      { 6, 26, 50, 74,  -1,  -1,  -1},  // Version 16
+      { 6, 30, 54, 78,  -1,  -1,  -1},  // Version 17
+      { 6, 30, 56, 82,  -1,  -1,  -1},  // Version 18
+      { 6, 30, 58, 86,  -1,  -1,  -1},  // Version 19
+      { 6, 34, 62, 90,  -1,  -1,  -1},  // Version 20
+      { 6, 28, 50, 72,  94,  -1,  -1},  // Version 21
+      { 6, 26, 50, 74,  98,  -1,  -1},  // Version 22
+      { 6, 30, 54, 78, 102,  -1,  -1},  // Version 23
+      { 6, 28, 54, 80, 106,  -1,  -1},  // Version 24
+      { 6, 32, 58, 84, 110,  -1,  -1},  // Version 25
+      { 6, 30, 58, 86, 114,  -1,  -1},  // Version 26
+      { 6, 34, 62, 90, 118,  -1,  -1},  // Version 27
+      { 6, 26, 50, 74,  98, 122,  -1},  // Version 28
+      { 6, 30, 54, 78, 102, 126,  -1},  // Version 29
+      { 6, 26, 52, 78, 104, 130,  -1},  // Version 30
+      { 6, 30, 56, 82, 108, 134,  -1},  // Version 31
+      { 6, 34, 60, 86, 112, 138,  -1},  // Version 32
+      { 6, 30, 58, 86, 114, 142,  -1},  // Version 33
+      { 6, 34, 62, 90, 118, 146,  -1},  // Version 34
+      { 6, 30, 54, 78, 102, 126, 150},  // Version 35
+      { 6, 24, 50, 76, 102, 128, 154},  // Version 36
+      { 6, 28, 54, 80, 106, 132, 158},  // Version 37
+      { 6, 32, 58, 84, 110, 136, 162},  // Version 38
+      { 6, 26, 54, 82, 110, 138, 166},  // Version 39
+      { 6, 30, 58, 86, 114, 142, 170},  // Version 40
+  };
+
+  // Type info cells at the left top corner.
+  private static final int[][] TYPE_INFO_COORDINATES = {
+      {8, 0},
+      {8, 1},
+      {8, 2},
+      {8, 3},
+      {8, 4},
+      {8, 5},
+      {8, 7},
+      {8, 8},
+      {7, 8},
+      {5, 8},
+      {4, 8},
+      {3, 8},
+      {2, 8},
+      {1, 8},
+      {0, 8},
+  };
+
+  // From Appendix D in JISX0510:2004 (p. 67)
+  private static final int VERSION_INFO_POLY = 0x1f25;  // 1 1111 0010 0101
+
+  // From Appendix C in JISX0510:2004 (p.65).
+  private static final int TYPE_INFO_POLY = 0x537;
+  private static final int TYPE_INFO_MASK_PATTERN = 0x5412;
+
+  // Set all cells to -1.  -1 means that the cell is empty (not set yet).
+  //
+  // JAVAPORT: We shouldn't need to do this at all. The code should be rewritten to begin encoding
+  // with the ByteMatrix initialized all to zero.
+  public static void clearMatrix(ByteMatrix matrix) {
+    matrix.clear((byte) -1);
+  }
+
+  // Build 2D matrix of QR Code from "dataBits" with "ecLevel", "version" and "getMaskPattern". On
+  // success, store the result in "matrix" and return true.
+  public static void buildMatrix(BitArray dataBits, ErrorCorrectionLevel ecLevel, int version,
+      int maskPattern, ByteMatrix matrix) throws WriterException {
+    clearMatrix(matrix);
+    embedBasicPatterns(version, matrix);
+    // Type information appear with any version.
+    embedTypeInfo(ecLevel, maskPattern, matrix);
+    // Version info appear if version >= 7.
+    maybeEmbedVersionInfo(version, matrix);
+    // Data should be embedded at end.
+    embedDataBits(dataBits, maskPattern, matrix);
+  }
+
+  // Embed basic patterns. On success, modify the matrix and return true.
+  // The basic patterns are:
+  // - Position detection patterns
+  // - Timing patterns
+  // - Dark dot at the left bottom corner
+  // - Position adjustment patterns, if need be
+  public static void embedBasicPatterns(int version, ByteMatrix matrix) throws WriterException {
+    // Let's get started with embedding big squares at corners.
+    embedPositionDetectionPatternsAndSeparators(matrix);
+    // Then, embed the dark dot at the left bottom corner.
+    embedDarkDotAtLeftBottomCorner(matrix);
+
+    // Position adjustment patterns appear if version >= 2.
+    maybeEmbedPositionAdjustmentPatterns(version, matrix);
+    // Timing patterns should be embedded after position adj. patterns.
+    embedTimingPatterns(matrix);
+  }
+
+  // Embed type information. On success, modify the matrix.
+  public static void embedTypeInfo(ErrorCorrectionLevel ecLevel, int maskPattern, ByteMatrix matrix)
+      throws WriterException {
+    BitArray typeInfoBits = new BitArray();
+    makeTypeInfoBits(ecLevel, maskPattern, typeInfoBits);
+
+    for (int i = 0; i < typeInfoBits.getSize(); ++i) {
+      // Place bits in LSB to MSB order.  LSB (least significant bit) is the last value in
+      // "typeInfoBits".
+      boolean bit = typeInfoBits.get(typeInfoBits.getSize() - 1 - i);
+
+      // Type info bits at the left top corner. See 8.9 of JISX0510:2004 (p.46).
+      int x1 = TYPE_INFO_COORDINATES[i][0];
+      int y1 = TYPE_INFO_COORDINATES[i][1];
+      matrix.set(x1, y1, bit);
+
+      if (i < 8) {
+        // Right top corner.
+        int x2 = matrix.getWidth() - i - 1;
+        int y2 = 8;
+        matrix.set(x2, y2, bit);
+      } else {
+        // Left bottom corner.
+        int x2 = 8;
+        int y2 = matrix.getHeight() - 7 + (i - 8);
+        matrix.set(x2, y2, bit);
+      }
+    }
+  }
+
+  // Embed version information if need be. On success, modify the matrix and return true.
+  // See 8.10 of JISX0510:2004 (p.47) for how to embed version information.
+  public static void maybeEmbedVersionInfo(int version, ByteMatrix matrix) throws WriterException {
+    if (version < 7) {  // Version info is necessary if version >= 7.
+      return;  // Don't need version info.
+    }
+    BitArray versionInfoBits = new BitArray();
+    makeVersionInfoBits(version, versionInfoBits);
+
+    int bitIndex = 6 * 3 - 1;  // It will decrease from 17 to 0.
+    for (int i = 0; i < 6; ++i) {
+      for (int j = 0; j < 3; ++j) {
+        // Place bits in LSB (least significant bit) to MSB order.
+        boolean bit = versionInfoBits.get(bitIndex);
+        bitIndex--;
+        // Left bottom corner.
+        matrix.set(i, matrix.getHeight() - 11 + j, bit);
+        // Right bottom corner.
+        matrix.set(matrix.getHeight() - 11 + j, i, bit);
+      }
+    }
+  }
+
+  // Embed "dataBits" using "getMaskPattern". On success, modify the matrix and return true.
+  // For debugging purposes, it skips masking process if "getMaskPattern" is -1.
+  // See 8.7 of JISX0510:2004 (p.38) for how to embed data bits.
+  public static void embedDataBits(BitArray dataBits, int maskPattern, ByteMatrix matrix)
+      throws WriterException {
+    int bitIndex = 0;
+    int direction = -1;
+    // Start from the right bottom cell.
+    int x = matrix.getWidth() - 1;
+    int y = matrix.getHeight() - 1;
+    while (x > 0) {
+      // Skip the vertical timing pattern.
+      if (x == 6) {
+        x -= 1;
+      }
+      while (y >= 0 && y < matrix.getHeight()) {
+        for (int i = 0; i < 2; ++i) {
+          int xx = x - i;
+          // Skip the cell if it's not empty.
+          if (!isEmpty(matrix.get(xx, y))) {
+            continue;
+          }
+          boolean bit;
+          if (bitIndex < dataBits.getSize()) {
+            bit = dataBits.get(bitIndex);
+            ++bitIndex;
+          } else {
+            // Padding bit. If there is no bit left, we'll fill the left cells with 0, as described
+            // in 8.4.9 of JISX0510:2004 (p. 24).
+            bit = false;
+          }
+
+          // Skip masking if mask_pattern is -1.
+          if (maskPattern != -1) {
+            if (MaskUtil.getDataMaskBit(maskPattern, xx, y)) {
+              bit = !bit;
+            }
+          }
+          matrix.set(xx, y, bit);
+        }
+        y += direction;
+      }
+      direction = -direction;  // Reverse the direction.
+      y += direction;
+      x -= 2;  // Move to the left.
+    }
+    // All bits should be consumed.
+    if (bitIndex != dataBits.getSize()) {
+      throw new WriterException("Not all bits consumed: " + bitIndex + '/' + dataBits.getSize());
+    }
+  }
+
+  // Return the position of the most significant bit set (to one) in the "value". The most
+  // significant bit is position 32. If there is no bit set, return 0. Examples:
+  // - findMSBSet(0) => 0
+  // - findMSBSet(1) => 1
+  // - findMSBSet(255) => 8
+  public static int findMSBSet(int value) {
+    int numDigits = 0;
+    while (value != 0) {
+      value >>>= 1;
+      ++numDigits;
+    }
+    return numDigits;
+  }
+
+  // Calculate BCH (Bose-Chaudhuri-Hocquenghem) code for "value" using polynomial "poly". The BCH
+  // code is used for encoding type information and version information.
+  // Example: Calculation of version information of 7.
+  // f(x) is created from 7.
+  //   - 7 = 000111 in 6 bits
+  //   - f(x) = x^2 + x^1 + x^0
+  // g(x) is given by the standard (p. 67)
+  //   - g(x) = x^12 + x^11 + x^10 + x^9 + x^8 + x^5 + x^2 + 1
+  // Multiply f(x) by x^(18 - 6)
+  //   - f'(x) = f(x) * x^(18 - 6)
+  //   - f'(x) = x^14 + x^13 + x^12
+  // Calculate the remainder of f'(x) / g(x)
+  //         x^2
+  //         __________________________________________________
+  //   g(x) )x^14 + x^13 + x^12
+  //         x^14 + x^13 + x^12 + x^11 + x^10 + x^7 + x^4 + x^2
+  //         --------------------------------------------------
+  //                              x^11 + x^10 + x^7 + x^4 + x^2
+  //
+  // The remainder is x^11 + x^10 + x^7 + x^4 + x^2
+  // Encode it in binary: 110010010100
+  // The return value is 0xc94 (1100 1001 0100)
+  //
+  // Since all coefficients in the polynomials are 1 or 0, we can do the calculation by bit
+  // operations. We don't care if cofficients are positive or negative.
+  public static int calculateBCHCode(int value, int poly) {
+    // If poly is "1 1111 0010 0101" (version info poly), msbSetInPoly is 13. We'll subtract 1
+    // from 13 to make it 12.
+    int msbSetInPoly = findMSBSet(poly);
+    value <<= msbSetInPoly - 1;
+    // Do the division business using exclusive-or operations.
+    while (findMSBSet(value) >= msbSetInPoly) {
+      value ^= poly << (findMSBSet(value) - msbSetInPoly);
+    }
+    // Now the "value" is the remainder (i.e. the BCH code)
+    return value;
+  }
+
+  // Make bit vector of type information. On success, store the result in "bits" and return true.
+  // Encode error correction level and mask pattern. See 8.9 of
+  // JISX0510:2004 (p.45) for details.
+  public static void makeTypeInfoBits(ErrorCorrectionLevel ecLevel, int maskPattern, BitArray bits)
+      throws WriterException {
+    if (!QRCode.isValidMaskPattern(maskPattern)) {
+      throw new WriterException("Invalid mask pattern");
+    }
+    int typeInfo = (ecLevel.getBits() << 3) | maskPattern;
+    bits.appendBits(typeInfo, 5);
+
+    int bchCode = calculateBCHCode(typeInfo, TYPE_INFO_POLY);
+    bits.appendBits(bchCode, 10);
+
+    BitArray maskBits = new BitArray();
+    maskBits.appendBits(TYPE_INFO_MASK_PATTERN, 15);
+    bits.xor(maskBits);
+
+    if (bits.getSize() != 15) {  // Just in case.
+      throw new WriterException("should not happen but we got: " + bits.getSize());
+    }
+  }
+
+  // Make bit vector of version information. On success, store the result in "bits" and return true.
+  // See 8.10 of JISX0510:2004 (p.45) for details.
+  public static void makeVersionInfoBits(int version, BitArray bits) throws WriterException {
+    bits.appendBits(version, 6);
+    int bchCode = calculateBCHCode(version, VERSION_INFO_POLY);
+    bits.appendBits(bchCode, 12);
+
+    if (bits.getSize() != 18) {  // Just in case.
+      throw new WriterException("should not happen but we got: " + bits.getSize());
+    }
+  }
+
+  // Check if "value" is empty.
+  private static boolean isEmpty(int value) {
+    return value == -1;
+  }
+
+  // Check if "value" is valid.
+  private static boolean isValidValue(int value) {
+    return value == -1 ||  // Empty.
+        value == 0 ||  // Light (white).
+        value == 1;  // Dark (black).
+  }
+
+  private static void embedTimingPatterns(ByteMatrix matrix) throws WriterException {
+    // -8 is for skipping position detection patterns (size 7), and two horizontal/vertical
+    // separation patterns (size 1). Thus, 8 = 7 + 1.
+    for (int i = 8; i < matrix.getWidth() - 8; ++i) {
+      int bit = (i + 1) % 2;
+      // Horizontal line.
+      if (!isValidValue(matrix.get(i, 6))) {
+        throw new WriterException();
+      }
+      if (isEmpty(matrix.get(i, 6))) {
+        matrix.set(i, 6, bit);
+      }
+      // Vertical line.
+      if (!isValidValue(matrix.get(6, i))) {
+        throw new WriterException();
+      }
+      if (isEmpty(matrix.get(6, i))) {
+        matrix.set(6, i, bit);
+      }
+    }
+  }
+
+  // Embed the lonely dark dot at left bottom corner. JISX0510:2004 (p.46)
+  private static void embedDarkDotAtLeftBottomCorner(ByteMatrix matrix) throws WriterException {
+    if (matrix.get(8, matrix.getHeight() - 8) == 0) {
+      throw new WriterException();
+    }
+    matrix.set(8, matrix.getHeight() - 8, 1);
+  }
+
+  private static void embedHorizontalSeparationPattern(int xStart, int yStart,
+      ByteMatrix matrix) throws WriterException {
+    // We know the width and height.
+    if (HORIZONTAL_SEPARATION_PATTERN[0].length != 8 || HORIZONTAL_SEPARATION_PATTERN.length != 1) {
+      throw new WriterException("Bad horizontal separation pattern");
+    }
+    for (int x = 0; x < 8; ++x) {
+      if (!isEmpty(matrix.get(xStart + x, yStart))) {
+        throw new WriterException();
+      }
+      matrix.set(xStart + x, yStart, HORIZONTAL_SEPARATION_PATTERN[0][x]);
+    }
+  }
+
+  private static void embedVerticalSeparationPattern(int xStart, int yStart,
+      ByteMatrix matrix) throws WriterException {
+    // We know the width and height.
+    if (VERTICAL_SEPARATION_PATTERN[0].length != 1 || VERTICAL_SEPARATION_PATTERN.length != 7) {
+      throw new WriterException("Bad vertical separation pattern");
+    }
+    for (int y = 0; y < 7; ++y) {
+      if (!isEmpty(matrix.get(xStart, yStart + y))) {
+        throw new WriterException();
+      }
+      matrix.set(xStart, yStart + y, VERTICAL_SEPARATION_PATTERN[y][0]);
+    }
+  }
+
+  // Note that we cannot unify the function with embedPositionDetectionPattern() despite they are
+  // almost identical, since we cannot write a function that takes 2D arrays in different sizes in
+  // C/C++. We should live with the fact.
+  private static void embedPositionAdjustmentPattern(int xStart, int yStart,
+      ByteMatrix matrix) throws WriterException {
+    // We know the width and height.
+    if (POSITION_ADJUSTMENT_PATTERN[0].length != 5 || POSITION_ADJUSTMENT_PATTERN.length != 5) {
+      throw new WriterException("Bad position adjustment");
+    }
+    for (int y = 0; y < 5; ++y) {
+      for (int x = 0; x < 5; ++x) {
+        if (!isEmpty(matrix.get(xStart + x, yStart + y))) {
+          throw new WriterException();
+        }
+        matrix.set(xStart + x, yStart + y, POSITION_ADJUSTMENT_PATTERN[y][x]);
+      }
+    }
+  }
+
+  private static void embedPositionDetectionPattern(int xStart, int yStart,
+      ByteMatrix matrix) throws WriterException {
+    // We know the width and height.
+    if (POSITION_DETECTION_PATTERN[0].length != 7 || POSITION_DETECTION_PATTERN.length != 7) {
+      throw new WriterException("Bad position detection pattern");
+    }
+    for (int y = 0; y < 7; ++y) {
+      for (int x = 0; x < 7; ++x) {
+        if (!isEmpty(matrix.get(xStart + x, yStart + y))) {
+          throw new WriterException();
+        }
+        matrix.set(xStart + x, yStart + y, POSITION_DETECTION_PATTERN[y][x]);
+      }
+    }
+  }
+
+  // Embed position detection patterns and surrounding vertical/horizontal separators.
+  private static void embedPositionDetectionPatternsAndSeparators(ByteMatrix matrix) throws WriterException {
+    // Embed three big squares at corners.
+    int pdpWidth = POSITION_DETECTION_PATTERN[0].length;
+    // Left top corner.
+    embedPositionDetectionPattern(0, 0, matrix);
+    // Right top corner.
+    embedPositionDetectionPattern(matrix.getWidth() - pdpWidth, 0, matrix);
+    // Left bottom corner.
+    embedPositionDetectionPattern(0, matrix.getWidth() - pdpWidth, matrix);
+
+    // Embed horizontal separation patterns around the squares.
+    int hspWidth = HORIZONTAL_SEPARATION_PATTERN[0].length;
+    // Left top corner.
+    embedHorizontalSeparationPattern(0, hspWidth - 1, matrix);
+    // Right top corner.
+    embedHorizontalSeparationPattern(matrix.getWidth() - hspWidth,
+        hspWidth - 1, matrix);
+    // Left bottom corner.
+    embedHorizontalSeparationPattern(0, matrix.getWidth() - hspWidth, matrix);
+
+    // Embed vertical separation patterns around the squares.
+    int vspSize = VERTICAL_SEPARATION_PATTERN.length;
+    // Left top corner.
+    embedVerticalSeparationPattern(vspSize, 0, matrix);
+    // Right top corner.
+    embedVerticalSeparationPattern(matrix.getHeight() - vspSize - 1, 0, matrix);
+    // Left bottom corner.
+    embedVerticalSeparationPattern(vspSize, matrix.getHeight() - vspSize,
+        matrix);
+  }
+
+  // Embed position adjustment patterns if need be.
+  private static void maybeEmbedPositionAdjustmentPatterns(int version, ByteMatrix matrix)
+      throws WriterException {
+    if (version < 2) {  // The patterns appear if version >= 2
+      return;
+    }
+    int index = version - 1;
+    int[] coordinates = POSITION_ADJUSTMENT_PATTERN_COORDINATE_TABLE[index];
+    int numCoordinates = POSITION_ADJUSTMENT_PATTERN_COORDINATE_TABLE[index].length;
+    for (int i = 0; i < numCoordinates; ++i) {
+      for (int j = 0; j < numCoordinates; ++j) {
+        int y = coordinates[i];
+        int x = coordinates[j];
+        if (x == -1 || y == -1) {
+          continue;
+        }
+        // If the cell is unset, we embed the position adjustment pattern here.
+        if (isEmpty(matrix.get(x, y))) {
+          // -2 is necessary since the x/y coordinates point to the center of the pattern, not the
+          // left top corner.
+          embedPositionAdjustmentPattern(x - 2, y - 2, matrix);
+        }
+      }
+    }
+  }
+
+}

OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/QRCode.java

@@ -0,0 +1,239 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+import com.google.zxing.qrcode.decoder.Mode;
+
+/**
+ * @author satorux@google.com (Satoru Takabayashi) - creator
+ * @author dswitkin@google.com (Daniel Switkin) - ported from C++
+ */
+public final class QRCode {
+
+  public static final int NUM_MASK_PATTERNS = 8;
+
+  private Mode mode;
+  private ErrorCorrectionLevel ecLevel;
+  private int version;
+  private int matrixWidth;
+  private int maskPattern;
+  private int numTotalBytes;
+  private int numDataBytes;
+  private int numECBytes;
+  private int numRSBlocks;
+  private ByteMatrix matrix;
+
+  public QRCode() {
+    mode = null;
+    ecLevel = null;
+    version = -1;
+    matrixWidth = -1;
+    maskPattern = -1;
+    numTotalBytes = -1;
+    numDataBytes = -1;
+    numECBytes = -1;
+    numRSBlocks = -1;
+    matrix = null;
+  }
+
+  // Mode of the QR Code.
+  public Mode getMode() {
+    return mode;
+  }
+
+  // Error correction level of the QR Code.
+  public ErrorCorrectionLevel getECLevel() {
+    return ecLevel;
+  }
+
+  // Version of the QR Code.  The bigger size, the bigger version.
+  public int getVersion() {
+    return version;
+  }
+
+  // ByteMatrix width of the QR Code.
+  public int getMatrixWidth() {
+    return matrixWidth;
+  }
+
+  // Mask pattern of the QR Code.
+  public int getMaskPattern() {
+    return maskPattern;
+  }
+
+  // Number of total bytes in the QR Code.
+  public int getNumTotalBytes() {
+    return numTotalBytes;
+  }
+
+  // Number of data bytes in the QR Code.
+  public int getNumDataBytes() {
+    return numDataBytes;
+  }
+
+  // Number of error correction bytes in the QR Code.
+  public int getNumECBytes() {
+    return numECBytes;
+  }
+
+  // Number of Reedsolomon blocks in the QR Code.
+  public int getNumRSBlocks() {
+    return numRSBlocks;
+  }
+
+  // ByteMatrix data of the QR Code.
+  public ByteMatrix getMatrix() {
+    return matrix;
+  }
+  
+
+  // Return the value of the module (cell) pointed by "x" and "y" in the matrix of the QR Code. They
+  // call cells in the matrix "modules". 1 represents a black cell, and 0 represents a white cell.
+  public int at(int x, int y) {
+    // The value must be zero or one.
+    int value = matrix.get(x, y);
+    if (!(value == 0 || value == 1)) {
+      // this is really like an assert... not sure what better exception to use?
+      throw new RuntimeException("Bad value");
+    }
+    return value;
+  }
+
+  // Checks all the member variables are set properly. Returns true on success. Otherwise, returns
+  // false.
+  public boolean isValid() {
+    return
+        // First check if all version are not uninitialized.
+        mode != null &&
+        ecLevel != null &&
+        version != -1 &&
+        matrixWidth != -1 &&
+        maskPattern != -1 &&
+        numTotalBytes != -1 &&
+        numDataBytes != -1 &&
+        numECBytes != -1 &&
+        numRSBlocks != -1 &&
+        // Then check them in other ways..
+        isValidMaskPattern(maskPattern) &&
+        numTotalBytes == numDataBytes + numECBytes &&
+        // ByteMatrix stuff.
+        matrix != null &&
+        matrixWidth == matrix.getWidth() &&
+        // See 7.3.1 of JISX0510:2004 (p.5).
+        matrix.getWidth() == matrix.getHeight(); // Must be square.
+  }
+
+  // Return debug String.
+  public String toString() {
+    StringBuffer result = new StringBuffer(200);
+    result.append("<<\n");
+    result.append(" mode: ");
+    result.append(mode);
+    result.append("\n ecLevel: ");
+    result.append(ecLevel);
+    result.append("\n version: ");
+    result.append(version);
+    result.append("\n matrixWidth: ");
+    result.append(matrixWidth);
+    result.append("\n maskPattern: ");
+    result.append(maskPattern);
+    result.append("\n numTotalBytes: ");
+    result.append(numTotalBytes);
+    result.append("\n numDataBytes: ");
+    result.append(numDataBytes);
+    result.append("\n numECBytes: ");
+    result.append(numECBytes);
+    result.append("\n numRSBlocks: ");
+    result.append(numRSBlocks);
+    if (matrix == null) {
+      result.append("\n matrix: null\n");
+    } else {
+      result.append("\n matrix:\n");
+      result.append(matrix.toString());
+    }
+    result.append(">>\n");
+    return result.toString();
+  }
+
+  public void setMode(Mode value) {
+    mode = value;
+  }
+
+  public void setECLevel(ErrorCorrectionLevel value) {
+    ecLevel = value;
+  }
+
+  public void setVersion(int value) {
+    version = value;
+  }
+
+  public void setMatrixWidth(int value) {
+    matrixWidth = value;
+  }
+
+  public void setMaskPattern(int value) {
+    maskPattern = value;
+  }
+
+  public void setNumTotalBytes(int value) {
+    numTotalBytes = value;
+  }
+
+  public void setNumDataBytes(int value) {
+    numDataBytes = value;
+  }
+
+  public void setNumECBytes(int value) {
+    numECBytes = value;
+  }
+
+  public void setNumRSBlocks(int value) {
+    numRSBlocks = value;
+  }
+
+  // This takes ownership of the 2D array.
+  public void setMatrix(ByteMatrix value) {
+    matrix = value;
+  }
+
+  // Check if "mask_pattern" is valid.
+  public static boolean isValidMaskPattern(int maskPattern) {
+    return maskPattern >= 0 && maskPattern < NUM_MASK_PATTERNS;
+  }
+
+  // Return true if the all values in the matrix are binary numbers.
+  //
+  // JAVAPORT: This is going to be super expensive and unnecessary, we should not call this in
+  // production. I'm leaving it because it may be useful for testing. It should be removed entirely
+  // if ByteMatrix is changed never to contain a -1.
+  /*
+  private static boolean EverythingIsBinary(final ByteMatrix matrix) {
+    for (int y = 0; y < matrix.height(); ++y) {
+      for (int x = 0; x < matrix.width(); ++x) {
+        int value = matrix.get(y, x);
+        if (!(value == 0 || value == 1)) {
+          // Found non zero/one value.
+          return false;
+        }
+      }
+    }
+    return true;
+  }
+   */
+
+}

OpenPGP-Keychain/src/org/sufficientlysecure/keychain/ui/ShareActivity.java

@@ -25,6 +25,7 @@ import org.sufficientlysecure.keychain.R;
 
 import com.actionbarsherlock.app.SherlockFragmentActivity;
 import com.google.zxing.integration.android.IntentIntegrator;
+import com.google.zxing.integration.android.IntentIntegratorSupportV4;
 
 import android.content.Intent;
 import android.os.Bundle;
@@ -70,7 +71,8 @@ public class ShareActivity extends SherlockFragmentActivity {
                     getResources().getText(R.string.shareKeyringWith)));
         } else if (ACTION_SHARE_KEYRING_WITH_QR_CODE.equals(action)) {
             // use barcode scanner integration library
-            new IntentIntegrator(this).shareText(keyringArmored.get(0));
+//            new IntentIntegrator(this).shareText(keyringArmored.get(0));
+//            new IntentIntegratorSupportV4(this).shareText(activity, text);
         }
     }
 }

OpenPGP-Keychain/src/org/sufficientlysecure/keychain/util/QrCodeUtils.java

@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2013 Dominik Schürmann <dominik@dominikschuermann.de>
+ * Copyright (C) 2011 Andreas Schildbach
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.sufficientlysecure.keychain.util;
+
+import java.util.Hashtable;
+
+import org.sufficientlysecure.keychain.Constants;
+
+import android.graphics.Bitmap;
+import android.graphics.Color;
+
+import com.google.zxing.BarcodeFormat;
+import com.google.zxing.EncodeHintType;
+import com.google.zxing.WriterException;
+import com.google.zxing.common.BitMatrix;
+import com.google.zxing.qrcode.QRCodeWriter;
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+
+public class QrCodeUtils {
+    public final static QRCodeWriter QR_CODE_WRITER = new QRCodeWriter();
+
+    /**
+     * Generate Bitmap with QR Code based on input.
+     * 
+     * @param input
+     * @param size
+     * @return QR Code as Bitmap
+     */
+    public static Bitmap getQRCodeBitmap(final String input, final int size) {
+        try {
+            final Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
+            hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
+            final BitMatrix result = QR_CODE_WRITER.encode(input, BarcodeFormat.QR_CODE, size,
+                    size, hints);
+
+            final int width = result.getWidth();
+            final int height = result.getHeight();
+            final int[] pixels = new int[width * height];
+
+            for (int y = 0; y < height; y++) {
+                final int offset = y * width;
+                for (int x = 0; x < width; x++) {
+                    pixels[offset + x] = result.get(x, y) ? Color.BLACK : Color.TRANSPARENT;
+                }
+            }
+
+            final Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
+            bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
+            return bitmap;
+        } catch (final WriterException e) {
+            Log.e(Constants.TAG, "QrCodeUtils", e);
+            return null;
+        }
+    }
+
+    /**
+     * Displays QrCode in Dialog
+     */
+    // public static void showQrCode(Activity activity, Bitmap qrCodeBitmap) {
+    // final Dialog dialog = new Dialog(activity);
+    // dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
+    // dialog.setContentView(R.layout.qr_code_dialog);
+    // final ImageView imageView = (ImageView) dialog.findViewById(R.id.qr_dialog_view);
+    // imageView.setImageBitmap(qrCodeBitmap);
+    // dialog.setCanceledOnTouchOutside(true);
+    // dialog.show();
+    // imageView.setOnClickListener(new OnClickListener() {
+    // public void onClick(final View v) {
+    // dialog.dismiss();
+    // }
+    // });
+    // }
+
+    /**
+     * Starts Scanning of Barcode with Barcode Scanner App, if Barcode Scanner is not installed
+     * requests install of it, done by using IntentIntegrator from Barcode Scanner
+     * 
+     * @param activity
+     */
+    // public static void scanQrCode(Activity activity) {
+    // IntentIntegrator.initiateScan(activity, R.string.no_barcode_scanner_title,
+    // R.string.no_barcode_scanner, R.string.button_yes, R.string.button_no);
+    // }
+    //
+    // /**
+    // * Return scanned QR Code as String, must be used in Activities onActivityResult(), done by
+    // * using IntentIntegrator from Barcode Scanner
+    // *
+    // * @param requestCode
+    // * @param resultCode
+    // * @param intent
+    // * @return QR Code content as String
+    // */
+    // public static String returnQrCodeOnActivityResult(int requestCode, int resultCode, Intent
+    // intent) {
+    // IntentResult scanResult = IntentIntegrator.parseActivityResult(requestCode, resultCode,
+    // intent);
+    //
+    // if (scanResult != null) {
+    // return scanResult.getContents();
+    // } else {
+    // return null;
+    // }
+    // }
+}