So i found this video here http://www.youtube.com/watch?v=xOqx7HCwZI8 Its one where a person places Chuck Norris' picture besides an iPhone 4 and the signal goes up, and when its removed it goes down. What id like to do is as the person slides that picture into the video i would want to put a picture a friend of mine so it looks like its his picture. Now this doesnt have to be perfect by any means but just basically cover Chuck Norris' picture. I tried playing around in iMovie but i couldnt figure out how to do it or if its even possible to do? Could someone person help me out?