diff --git a/xep-0180.xml b/xep-0180.xml index ee0b4611..71ea710e 100644 --- a/xep-0180.xml +++ b/xep-0180.xml @@ -27,6 +27,12 @@ Chen Milton.Chen@vseelab.com + + 0.8 + 2007-05-23 + psa +

Corrected examples to use video codecs; added clockrate attribute.

 + 0.7 2007-05-23 @@ -109,15 +115,14 @@

A Jingle video session is described by one or more encodings contained within a wrapper &DESCRIPTION; element. In the language of RFC 4566 these encodings are payload-types; therefore, each <payload-type/> child element specifies an encoding that can be used for the video stream. Such encodings are often used in the context of the Real-time Transfer Protocol (RTP; see RFC 3550) but may be used in other contexts as well. The most common encodings for the Audio/Video Profile (AVP) of RTP are listed in &rfc3551; (these "static" types are reserved from payload ID 0 through payload ID 95), although other encodings are allowed (these "dynamic" types use payload IDs 96 to 127) in accordance with the dynamic assignment rules described in Section 3 of RFC 3551. The &PAYLOADTYPE; element's 'id' attribute is REQUIRED and its 'name' attribute is RECOMMENDED. The encodings SHOULD be provided in order of preference.

- + - - - - + + + ]]>

The &DESCRIPTION; element is intended to be a child of a &CONTENT; element as specified in XEP-0166.

@@ -127,51 +132,67 @@ Attribute Description Datatype/Units + Inclusion channels The number of channels (e.g., 2 for stereoscopic video) positiveInteger (defaults to 1) + OPTIONAL + + + clockrate + The sampling frequency in Hertz + positiveInteger + RECOMMENDED height The vertical extent of the displayed video, in pixels positiveInteger + RECOMMENDED id A unique identifier for the payload type positiveInteger + REQUIRED layer The relationship of a layer to the "bottom" of the stack, where 0 = bottom (the first layer) nonNegativeInteger + OPTIONAL name A name for the payload type string + RECOMMENDED for static payload types, REQUIRED for dynamic payload types transparent Whether or not a layer is transparent boolean + OPTIONAL width The horizontal extent of the displayed video, in pixels positiveInteger + RECOMMENDED x The horizontal starting point of a tile, in pixels from the origin point positiveInteger + OPTIONAL y The vertical starting point of a tile, in pixels from the origin point positiveInteger + OPTIONAL

Each <payload-type/> element MAY contain one or more child elements that specify particular parameters related to the payload. For example, as described in draft-ietf-avt-rtp-theora This Internet-Draft has expired; see <http://svn.xiph.org/trunk/theora/doc/draft-ietf-avt-rtp-theora-00.txt> for an archived version., the "configuration", "configuration-uri", "delivery-method", and "sampling", parameters may be specified in relation to usage of the Theora See <http://www.theora.org/>. codec. Where such parameters are encoded via the "fmtp" SDP attribute, they shall be represented in Jingle via the following format:

@@ -194,14 +215,14 @@ sid='v1d30k1ll3dth3r4d10st4r'> - + - - - + + + @@ -244,12 +265,8 @@ - - - - - - + + @@ -310,10 +327,10 @@ m=

In the context of Jingle video sessions, the <media> is "video", the <port> is the preferred port for such communications (which may be determined dynamically), the <transport> is whatever transport method is negotiated via the Jingle negotiation (e.g., "RTP/AVT"), and the <fmt list> is the payload-type ID.

For example, consider the following static payload-type:

+ ]]>

If the payload type is dynamic (payload-type IDs 96 through 127 inclusive), it SHOULD be mapped to an SDP media field plus an SDP attribute field named "rtpmap".

For example, consider a VC-1 payload such as that described in &rfc4425;: