I don't know if image cropping is a good metaphor. The algorithm for removing copyrighted music while preserving other sound presumably "subtracts" the copyrigh

I don't know if image cropping is a good metaphor. The algorithm for removing copyrighted music while preserving other sound presumably "subtracts" the copyrighted music. Thus, the copyrighted music is used to create the music-less video. IANAL, so I defer to anyone with legal expertise.