ffmpeg - Audio - Add more audio tracks to a video

ffmpeg -i input.mp4 -i audio.mp3 -map 0 -map 1 -c copy output.mp4

NOTE: Using the -map flag means that you can specify which streams to keep.

  • -map 0 is input.mp4.
  • -map 1 is audio.mp3.
  • The streams of both inputs are copied together as -c copy means no re-encoding is done.