ffmpeg \ -i in.mkv \ -sub_charenc UTF-8 \ -i in.srt \ -map 0:v:0 -vcodec copy \ -map 0:a:0 -acodec copy \ -map 0:a:1 -acodec ac3 -b:a 640k \ -map 1:s:0 -scodec mov_text \ -metadata:s:s:0 language=eng \ -disposition:s:0 forced \ out.mp4