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+# ImageDownloader
+When [Conversations](https://conversations.im) uploads an encrypted image with [XEP-0363: HTTP Upload](http://xmpp.org/extensions/xep-0363.html) it appends the encryption key as an anchor to the URL.
+
+The anchor is made of 96 characters which represent 48 bytes in HEX. The first 16 bytes are the IV the last 32 bytes are the key.
+
+The encryption mode is ```aes-gcm```. The authentcation tag of 16 bytes is appended to the file.
+
+This Java project provides sample code on how to download and dercypt a file. Output is to stdout. Redirect to file or pipe to image viewer.
+
+Usage: ```java -jar ImageDownloader.jar http://host.tld/path/to/file.jpg#theivandkey```