new String[]{"-i", "input.avi", "-b:v", "64k", "-bufsize", "64k", "output.avi"};
You must split your arguments each into one array element or you'll get errors such as "Unrecognized option"
it's not necessary to write "ffmpeg" in the beginning, FFmpeg-Android will add that automatically.
note: the String[] is passed directly onto ProcessBuilder.
Here's a copy paste ready description.
Cheers!