I think this is the link he was referring to:
https://github.com/frc3946/Stronghold
If you have more questions, ask away. With GRIP coming out last year, it's made vision processing at lot easier. Our programmers started out in GRIP but since it was new, they were still working out installation instructions for the PI. So our programmers decided to use Python and OpenCV on the Pi. They did a presentation on our implementation
https://www.youtube.com/watch?v=ZNIlhVzC-4g
Brian