[FFmpeg-devel] [PATCH] QCELP decoder

Kenan Gillet kenan.gillet
Sat Oct 4 04:31:39 CEST 2008


On Fri, Oct 3, 2008 at 6:46 PM, Baptiste Coudurier
<baptiste.coudurier at smartjog.com> wrote:
> Kenan Gillet wrote:
[...]
>> It seems that setting the sample_rate in AVCodecContext
>> from the qcelp_decode_init function has no effect on how
>> FFmpeg 'sees' the sample_rate.
>
> There is atm some asynchronous behaviour, because decoder is not inited
> before infos are printed.
>
>> That explains why the 24khz sample kinda works ;)
>>
>> Is it the expected behavior ?
>
> It seems you have to _not_ set it to 8000 hz to get correct synced sound.
>
>> If it is, it seems the only place to change the sample_rate in
>> AVCodecContext is to do it in libavcodec/mov.c.
>>
>> Until now, all the files I came across had a valid sample_rate,
>> so maybe we can just drop this check and warning.
>
> In this case, you must not change the sample rate to 8000, you must let
> it to 24 khz like quicktime does and plays correctly, otherwise you get
> distorted sound.
>
> [...]
>
Thanks, I just removed any sample rate code from the decoder init function.

Kenan




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