I feel like there are two extremes for how this request will be received. Either I'm completely ignorant and this already exists, or I'm out of my mind and this is a nightmare (or straight up impossible) to program.
I want to be able to tap the spacebar to establish the BPM for playback, but as I speed up or slow down, the footage not only starts playing back at the current BPM rate, but rubberbands BACK to keep up with me.
E.g. If I have footage of a timer counting up seconds, and I am tapping at a BPM that's constantly changing, no matter how fast or slow I go (within reason), when I've tapped 30 times on the spacebar, I will see "30" in the footage.
Right now, when I do a movie timed to live orchestra, I have to cut it up into hundreds of edits with tails to account for unique performance speed. This would be MASSIVE for opera and concerts. The ability to let a musician on a midi pad keep a video file in perfect time to the maestro would be game changer to the "MOVIE in Concert" genre.
(Preemptive edit: Yes, I am aware click tracks exist. No, most conductors hate them and ask for another solution.)
Thanks all.