[FFmpeg-devel] lavfi: audio filters cleanup and fixes

[Clément Bœsch]

Hi,

Thanks to Stefano I was able to understand why -t parameter got ignored: the
API needs you to copy props from in to out samples buffer ref, and reset
changing props after each filter_samples. In the case of the aresample filter,
there is also a need to scale the PTS and redefine the number of samples
according to the result of the resampling. The filter is still broken with some
MP3, but it works with "clean" input.

I'd like to push this patchset ASAP if no one object since it fixes a few
things and simplifies a lot the filters.