Strip audio / subtitle stream with ffmpeg

$ ls -1 *.mp4 | xargs -I{} ffmpeg -y -i {} -map 0 -map -0:a:0 -c copy /path/to/out/{}

-map -0:a:0 removes the 0th audio stream.

• v - video, such as -map -0:v
• a - audio, such as -map -0:a
• s - subtitles, such as -map -0:s
• d - data, such as -map -0:d