Add chaquopy-ffmpeg package

[macmegan]

• See:
  • FFmpeg #143
  • Failed to install av #1012
• Built and tested on arm64-v8a, x86, and x86_64 for Python 3.10

[mhsmith]

Thanks, I'll have a look at this as soon as I can.

You mentioned #1012: does that mean you've successfully built av as well? If so, please create another PR for that.

[mhsmith]

Sorry for taking so long to look at this.

Even if this recipe builds the ffmpeg library, the test doesn't verify that the library actually works, because all it does is construct a command line without executing it.

Also, ffmpeg-python's documentation clearly says that it calls ffmpeg as an executable on the PATH, which wouldn't work on Android anyway (#605). So a different testing approach would be needed.