I didn't think real-time video tracking on an ATmega was possible . . . they only did black/white, but now I'm thinking color might even be possible . . . ok, so they cheated a bit and used a white cloth behind them, but hey, it's a proof of concept. http://people.ece.cornell.edu/land/courses/ece4760/FinalProjects/s2010/aip23_kaf42/aip23_kaf42/index.html
For our project, we wanted to push the video sampling and processing capabilities of the ATmega644 8-bit microcontroller. Using a high-speed analog-to-digital converter as an input device, we were able to sample a reasonably high-resolution grayscale image from a color camera's video output. Using this grayscale image, we are able to track objects and recognize shapes that stood out from the background by a customizable threshold.
We created a game called Human Tetris to show off the system's shape recognition capability. In this game, players must contort their bodies into shapes displayed on screen in a given amount of time. To demonstrate the potential for our device to expand to a larger game library, we also implemented a port of Brick Breaker and another ineractive game called Whack-a-Mole. Brick Breaker shows off the object tracking capability, where players must physically interact with the bouncing ball to keep it on screen and break bricks. Whack-a-Mole requires a player to flail around on the screen to hit all of the moles before they disappear.