How to splice images into video frames?

Hello! Boring weekend but I have been a bit too tired and busy to do self bondage so I thought of this small experiment to try out. 

I was wondering if I could test out subliminal frames by creating a video I like with a randomly selected image inside. The image would be of two circles with visually unique colors connected by a line and I would randomly pick one not knowing which is which to add to the video. 

After a week of watching spliced videos I get one of the colors and try to match it with the opposing color to test if subliminally inserted images have an impact on our decision making process.

Should in theory be a safe and easy way to test the impact subliminals might have on our decisions. Need some way to do this though. If someone could teach me how to make my phone's screen have these frames that would be even better.

Anyways do let me know how this idea is and how I could go about doing it.

[Like Ra]

It can be done by ffmpeg, kdenlive, gimp. Are you on Linux, Windows, Mac?