Review requested: audio/atrac3 media type registration

[actech]

Hi Mark,

We think it is very useful that the all of decoding parameters
are available before decoding, without any parsing of payload data.
For example, if the receiver has only 48000Hz D/A clock, the
receiver can activate sampling rate converter before 44100Hz decoding,
or send back decoder capability(refusal of 44100Hz streaming) to
sender side in SDP offer-answer exchange.

In addition, we made a discuss with AVT chair that also ATRAC3
media type registration should have a bit-rate parameter
even if it can be only 44100, considering the consistency
that ATRAC-X and ATRAC Advanced Lossless media type have
bit-rate parameter.

Best Regards,

Jun


> On 2/26/08, actech <actech at jp.sony.com> wrote:
>> Hi Mark,
>>
>>  In ATRAC receiver side, it is required to know sampling frequency, bit-rate and
>>  channel configuration in order to switch and initialize the decoder and
>>  associated hardware for immediate starting of ATRAC3, ATRAC-X or ATRAC Advanced
>>  Lossless decoding.
>>
>>  We think it is the best way to signal above parameters in SDP session with
>>  media type registarion procedure.
> 
> Hi Jun.  I suppose that answers my question about a recipient being
> able to determine those parameters from the data itself, but I'm still
> not clear why a parameter is marked as required when it can only have
> a single value.  Is it perhaps because other values may be supported
> in the future?  Some other reason?
> 
> Mark.
> 
> 
>