As far as interfacing with your sensor, it seems possible that you could interface that directly to your computer and you wouldn't need an Arduino at all.
OTOH, you could do it entirely with Arduino and no computer if you want to make a video noise-generator. Then it would be simply a matter of turning it on or off.
How can you imagine that?
I think I found my way now with SuperCollider where I both could open up a video file or create the picture by myself. Nevertheless I'm interested in these two ideas of yours as I can't imagine really what you're talking about. In my case the TV screen, the sensor and the laptop will be on a stage that is in the middle of a room where people can go all around the scenery so I don't really have the opportunity of sitting somewhere hidden and pressing buttons (although that would maybe also be worth a 'worst case scenario': taking the remote control and simply turn up the brightness
Thanks for your efforts, KE7GKP.