
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@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.