Remove audio or video from a movie in QuickTime Player on Mac
With QuickTime Player, you can remove audio from a movie so that you’re left with a video-only file. You can also choose to keep an audio-only file by removing the video from the movie.
In the QuickTime Player app on your Mac, open the movie you want to work on.
Do one of the following:
To remove the sound from the movie, choose Edit > Remove Audio.
Your file is now video only.
To remove the video from the movie, choose Edit > Remove Video.
Your file is now audio only.