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[AVT] Interop issue with H263-1998

Dear all,

I have an issue with the definition of the H263-1998 media type.
In the RFC 2429, no optional parameters are defined, implying that any valid H263+ stream could be streamed.
In the RFC 4629, that obsoletes 2429, various optional parameters are specified, which allow specifying the (decoder) support to the various annexes.

What confuses me is the following statement in RFC 4629, concerning H263-1998

   Interoperability considerations:

      These are receiver options; current implementations will not send
      any optional parameters in their SDP.  They will ignore the
      optional parameters and will *** encode the H.263 stream without any ***
      of the annexes.  Most decoders support at least QCIF and CIF fixed
      resolutions, and they are expected to be available almost in every
      H.263-based video application.

Indeed my understanding would be quite different, and I would have written instead:

      These are receiver options; current implementations will not send
      any optional parameters in their SDP.  They will ignore the
      optional parameters and will *** encode the H.263+ stream with possibly all ***
      of the annexes.  Most decoders support at least QCIF and CIF fixed
      resolutions, and they are expected to be available almost in every
      H.263-based video application.


Any clarification would be welcomed

Best regards
Guido Franceschini
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