[FFmpeg-soc] Trying to write a new filter but unclear on callback order

[Stefano Sabatini]

On date Saturday 2010-03-27 07:46:26 -0400, Brandon Mintern encoded:
> I'm trying to build a filter called "clone" (as discussed with Vitor
> on #ffmpeg-devel). I was modeling my filter after fifo, but apparently
> I'm wrong about the callback process (sidenote: a more detailed
> explanation in the wiki documentation would be very helpful!). I think
> I'm reasonably close with the code I have, but I can't finish it until
> I better understand the callback order in the filter chain. I would
> appreciate it if someone could point me in the write direction.

Quick reply as I don't have much time at this moment: enable the DEBUG
symbol in avfilter.c and use -logleve debug, that should show you when
every callback is called and understand how the filterchain processing
stuff works.

And thanks for the contribution. BTW if you're a student and
interested we have a libavfilter GSoC task just waiting for you, or
for any interested student.

Regards.