Android frame by frame player example
see also http://writingminds.github.io/ffmpeg-android-java/
https://stackoverflow.com/questions/4614365/control-the-playback-speed-of-video-in-android
https://stackoverflow.com/questions/18124688/playing-video-frame-by-frame
https://stackoverflow.com/questions/22684347/extract-all-video-frames-in-android