Review requested: audio/atrac3 media type registration

[Tom Taylor]

Please review the following media type registration. The source document is 
http://www.ietf.org/internet-drafts/draft-ietf-avt-rtp-atrac-family-13.txt, 
which is currently undergoing Working Group Last Call in the AVT Working Group.

Tom Taylor
AVT co-Chair

    The media subtype for the Adaptive TRansform Codec version 3 (ATRAC3)
    uses the template defined in RFC 4855 [6].

    Note, any unknown parameter MUST be ignored by the receiver.

    Type name:  audio

    Subtype name:  atrac3

    Required parameters:
    rate:  Represents the sampling frequency in Hz of the original
    audio data.  Permissible value is 44100 only.

    baseLayer:  Indicates the encoded bit-rate in kbps for the audio
    data to be streamed.  Permissible values are 66, 105 and 132.

    Optional parameters:

    ptime: see RFC4566[2]

    maxptime: see RFC4566[2]
    The value of the parameter MUST be a multiple of 23.2(ms).
    If this parameter is not present, the sender MAY encapsulate
    a maximum of 6 encoded frames into one RTP packet, in streaming
    of ATRAC3.

    maxRedundantFrames:  The maximum number of redundant frames that may
    be sent during a session in any given packet under the redundant
    framing mechanism detailed in the draft.  Allowed values are integers
    in the range of 0 to 15, inclusive.  If this parameter is not used, a
    default of 15 MUST be assumed.

    Encoding considerations:  This media type is framed and contains
    binary data.

    Security considerations:  See Section 9 of this document.

    Interoperability considerations: none

    Published specification: none

    Applications that use this media type:
         Audio and video streaming and conferencing tools.

    Additional information: none

    Magic number(s): none
    File extension(s): 'at3', 'aa3', and 'omg'
    Macintosh file type code(s): none

    Person & email address to contact for further information:
    Mitsuyuki Hatanaka
    actech at jp.sony.com

    Intended usage: COMMON

    Restrictions on usage:  This media type depends on RTP framing,
                    and hence is only defined for transfer via RTP.

    Author/Change controller:
    Mitsuyuki Hatanaka
    actech at jp.sony.com