Allow for Video input for the background

[FatalUserK]

I have not used this program yet as this was the first thing I noticed it was lacking, I notice this repo has not been touched in a while, but I truly hope this gets added, as I would love to be able to make transcriptions of songs with a darkened blurred version of its music video in the background.
This would just be very handy, much appreciated for reading over this if you are, feel free to let me know if this isn't viable so I at least know o/

[NeroBlackstone]

This is too much for a midi visualizer. Just export the video with a transparent channel and you can edit your video in any video editor.