[FFmpeg-devel] [PATCH] Add af_resample - sample fmt and channel layout conversion filter

S.N. Hemanth Meenakshisundaram smeenaks
Fri Oct 1 18:58:46 CEST 2010

 On 10/01/2010 09:40 AM, Stefano Sabatini wrote:
> On date Monday 2010-09-27 02:50:41 +0200, Michael Niedermayer encoded:
>> On Mon, Sep 27, 2010 at 02:41:16AM +0200, Stefano Sabatini wrote:
>>> On date Monday 2010-09-27 02:21:49 +0200, Michael Niedermayer encoded:
>>>> On Mon, Sep 27, 2010 at 12:40:31AM +0200, Stefano Sabatini wrote:
>>> [...]
>>>>>> the functions belong to libavfilter
>>>>>> what is the plan to move them there?
>>>>> Impossible as lavc uses that functions internally.  The plan was to
>>>> resample uses them, resample doesnt belong to lavc, not more than
>>>> sws would belong there
>>>>> directly use them, and move to something better when we'll have a
>>>>> revisited resampling/conversion API, a libavresample was mentioned.
>>>>> Since this is not going to take small time, the idea was to use the
>>>>> quickest solution and not stall audio lavfi development.
>>>> the quickest is to copy the 2 pages of poor code not to export it as
>>>> public ABI/API from the wrong lib
>>>> that API/ABI requires maintaince and is not a small burden when things
>>>> have to be moved to the correct place or when API/ABI changes which with
>>>> such trashy code will happen unless development stops
>>> OK so the quickest path looks like to duplicate the code as it was
>>> done in the original version from Hemanth...
>> yes, i dont like it but i think this is a rare case where this will cause
>> fewer problems
>> also the code in libavcodec should be marked as deprecated as soon as possible
> Updated patch based on an old patch from Hemanth (Hemanth feel free to
> continue to discuss starting from this patch).
> My plan is to get -af implemented in ffplay, this requires these
> steps:
> * resample filter
> * resample filter auto-insertion provided by the lavfi framework
> * avfilter_get_audio_buffer_ref() or the equivalent, required for
>   eliminating an unnecessary memcpy
> * ffplay -af
> Once it is possible to test somehow libavfilter with audio, then we
> can move to ffmpeg:
> * asrc_buffer
> * ffmpeg -af
> * audio lavfi tests
> Regards.

Hi Stefano,

I couldn't find time so far this week. Will simplify the
get_audio_buffer_ref call and check the old patches again this weekend.


More information about the ffmpeg-devel mailing list