Reverse/Inverted Color Key or Reverse Alpha Channel in OBS?


New Member

I'm trying to achieve some kind of reverse color key effect in OBS.
I'm creating a sort of music education show were I play the piano, and I want to overlay certain colors over certain notes on the camera feed.
That part is easy:
Screenshot (38).png

However, when I play those keys on the piano, my hands go underneath the overlay, so you can't see what i'm playing.
I've tried making the overlay more transparent, but that just dulls the colors and still makes it hard to see what I'm doing.

I had the idea to duplicate the camera layer, wear blue rubber gloves, and do a reverse color key on the blue gloves.
This way, the top layer would only show my hands, the middle layer is the color overlay, and the bottom layer is the normal camera view of the piano.

This all works great (the blue gloves are easily picked up by the color key effect), but I can't figure out how to invert the alpha channel on that layer.
Is this possible? Does anyone have any workaround ideas?