Question about the movie Forgetting Sarah Marshall?

In the movie, Peter Bretter goes to Hawaii and chats with his step-brother Brian via webcam. Brian has some kind of program on his webcam that lets him change the backgound scene when Peter views it. It’s almost like Brian is in front of a blue screen and something is being projected on it. The Question: Is there realy a program that allows you to do that?

Did any of that make sense?