Created by: fvollmer
The pyav resampler and the fifo can't handle any pts inconsistencies, but ffmpeg can. If we take a look at the ffmpeg tool we can see that the heavy lifting for the resampling is done by the aformat filter (https://github.com/FFmpeg/FFmpeg/blob/169259d9a381a3c2132672da5c5f250fa194fb4d/fftools/ffmpeg_filter.c#L607). The fifo is implemented by the the buffersink (https://github.com/FFmpeg/FFmpeg/blob/169259d9a381a3c2132672da5c5f250fa194fb4d/fftools/ffmpeg_filter.c#L1113).
This PR to matches the pyav resampler behavior to the ffmpeg tool by using the same filters. This also simplifies the code quite a bit.
Fixes #761 (closed) Depends on #765