Free program that can subtract background music is needed

The world urgently needs a free program that can subtract background music from a field recording.

The purpose is to prevent censorship of people's video recordings of how cops treat the public. The cops try to cause censorship of these recordings by playing loud copyrighted music which they hope will trigger automated copyright censorship filters to delete the recordings.

The program needs to work well enough to ensure that automated copyright censorship filters not trigger. It needs to cope with noise and distortion introduced in making the field recording, but there is no need to make it work “better” than that.

The program could ask the user to provide a recording of the music to be subtracted; users will generally be able identify that in the platform they want to post the video in.