Support playback of audio from MP4 files containing video streams (e.g. MP4 with H.264 video + AAC audio)

[phasires]

I’d like to request support for playing the audio stream from MP4 files that contain both video and audio.

Currently, kew ignores MP4 files that include a video track, even when there’s a valid AAC audio stream. It would be great if kew could recognize these as valid music sources and play the audio (similar to how many other audio players handle MP4/M4A).

Tested on Arch Linux (ffmpeg n8.0).

[ravachol]

Originally it had support for mp4 but it was requested that it should be made optional:

See: https://github.com/ravachol/kew/issues/165

I ended up removing it. It could be an option of course, but I'm trying to keep options to a minimum, because ideally most people shouldn't have to spend time configuring things. Maybe an option is the best option though.

[ravachol]

Turns out adding it back is easier said than done. When we used FFmpeg it was easy, now we use much smaller FAAD and it's not. I'm not finding a good/small solution in c for fully supporting mp4 files in combination with FAAD.