[CELT-dev] Variable frame size and API changes

Pascal Charest c.lacsap at gmail.com
Wed May 19 07:54:59 PDT 2010


Hi Jean-Marc,

The current CELT over DAB framing allows to user to select between 24,
12, 8 and 6 ms frame size. Although it is not necessary, it would be
easy to add support for 4, 3, 2 and 1 ms.

By the way, it was really easy to create a protocol for CELT over DAB
because this codec offers great choices for the frame size and
bitrate. Moreover, the availability of CBR was the most useful
property because the underlying channel is constant bitrate.

Pascal

2010/5/18 Jean-Marc Valin <Jean-Marc.Valin at usherbrooke.ca>:
> Hi,
>
> What frame size are you using to get 24 ms "chunks"? I assume that's not 9*2.5
> ms, right?
>
>   Jean-Marc
>
> Quoting Pascal Charest <c.lacsap at gmail.com>:
>
>> Hi Jean-Marc,
>>
>> DAB frame size is based on MPEG1/2 audio, which is 24ms. As such, any
>> 24ms compatible frame size would keep the CELT over DAB framing easier
>> (e.g. 24, 12, 8, 6, ... ms).



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