2.2.7 RTCP Profile-Specific Extension

The profile-specific extension is appended to the SR or RR reports and is used to carry additional information not contained in the SR or RR reports. It is a block of data that immediately follows the SR or RR report packets. As with the rest of the RTP and RTCP fields, all integer fields on profile-specific extensions are in network order (most significant byte first). If a profile-specific extension is not used, it still MUST be parsed correctly by the receiver, even if it is ignored.

The common header for such extensions is defined as follows.


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1
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9

2
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1

Type

Length

ExtensionInfo (variable)

...

Type (2 bytes): The extension type.

Length (2 bytes): The extension length in bytes, including this header.

ExtensionInfo (variable): This field depends on the extension type.