How can I determine if a codec / container combination is compatible with FFmpeg?

Question

I\'m looking at re-muxing some containers holding audio and video such that I extract the best, first audio stream, and store it in a new container where e.g. only

Answer 1

For each individual muxer, there is usually a codec tag writing function.That function will check against a list in another source file or work through a switch statement in the same. There is no central roster or container-matching utility function. Your best bet is to identify the codec id in libavcodec/allcodecs.c and then grep in libavformat/ for that ID, particularly within files suffixed with enc e.g. matroskaenc.c.