Demo video with transparent background.

I have a simple 2D game and would like to record a demo video using OBS software. Is it technically feasible to make the game background transparent and then take the video recording (mp4?) and add a background in "post-production" using After Effects or similar editor?

 

I don't think so, other than doing some setup that would "outsource" render texture of "behind-the-app" with some other software and supplying it to UI, You should be able to do it relatively simply with standard chroma keying.

Just make the background pink/green/blue/whatever color You use least, and "Green-screen" it out. Or experiment with AR rendering, maybe You can feed the background image as a "camera" stream?

 

Thank you! "Green-screen" is a good idea. It will be interesting to try.