Types review: new parameters for audio/mpeg4-generic

[Tom Taylor]

Review is requested for the parameters defined below. These parameters are 
optional additions for media type audio/mpeg4-generic. The quoted IANA 
Considerations section comes from draft-ietf-avt-mps-01.txt.

Tom Taylor
AVT Co-Chair

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5.  IANA Considerations

    This memo defines additional optional format parameters to the Media
    subtype mpeg4-generic.  These parameters SHALL only be used in
    combination with the AAC-lbr or AAC-hbr modes (cf. [RFC3640] section
    3.3).

5.1.  Media Type registration

    This memo defines the following additional optional parameters which
    SHALL be used if MPEG Surround data is present inside the payload of
    an AAC elementary stream.

       MPS-profile-level-id: A decimal representation of the MPEG
       Surround Profile Level indication as defined in [14496-3].  This
       parameter MUST be used in the capability exchange or session
       set-up procedure to indicate the MPEG Surround Profile and Level
       that the decoder must be capable in order to decode the stream.

       MPS-config: A hexadecimal representation of an octet string that
       expresses the AudioSpecificConfig (ASC) as defined in [14496-3]
       for MPEG Surround.  The ASC is mapped onto the hexadecimal octet
       string in an MSB-first basis.  The AOT in this ASC SHALL have the
       value 30.  The SSC inside the ASC MUST have the
       sacPayloadEmbedding flag set to 1.

5.2.  Registration of Mode Definitions with IANA

    This memo defines the modes MPS-hbr and MPS-lbr.