[FFmpeg-soc] libavfilter audio work - qualification task

[Stefano Sabatini]

On date Thursday 2010-04-01 11:53:42 -0700, Baptiste Coudurier encoded:
> On 03/31/2010 10:44 PM, S.N. Hemanth Meenakshisundaram wrote:
> >
> >Hi All,
> >
> >Based on the posts above, here's what I was thinking of doing as a
> >qualification task :
> >
> >1. Fix the configure_filters function in ffmpeg.c to work for both video
> >and audio filters.
> >
> >2. Bring the af_null and af_vol filters from soc/afilters to
> >soc/avfilter and generalize avfilter framework to work with the af_*
> >filters. This should involve a minimal design for the avfilter audio
> >changes.
> >
> >3. af_vol currently just scales input by two. Modify af_vol to have some
> >basic volume filter functionality.
> >
> >Please let me know if I have understood the tasks right and if this will
> >work as a qualification task.

I believe that is even too burden as a qualification task, much of the
libavfilter audio design has yet to be done.

> A qualification task could be to add AVCodecContext get_buffer
> functionality to audio decoders.

As alternative to this, any video libavfilter task should be OK
(e.g. port a filter from MPlayer/libmpcodecs or write a new one), note
that vf_imlib.c is *not* a valid qualification task (see
https://roundup.ffmpeg.org/issue302), this should help you to get
confident with the FFmpeg/libavfilter API.

I especially recommend: a deinterlace filter (check the code in
libavcodec/imgconvert.c), a libfreetype wrapper (check as reference
vhook/drawtext.c in ffmpeg-0.5).

Ask here or on IRC if you have questions.

Regards.