This is roughly what I'm looking at making. I'll be using code from my previous webcam examples and merging that with the beginnings of code that will judge whether the user ('player' is such a strong word at this stage!) has made a motion at the correct time and in the correct place on the screen.
The example shall work as follows:
1. The blocks fall down the screen the image of the user.
2. The user shall jab upwards into the picture with their right or left hand when the corresponding block reaches the thick line at the bottom of the screen.
3a. If the user responds early, late or not at all then nothing will register (- in DJ Max Portable terms, this would count as a failure and would reduce the chances of finishing the song)
3b. If the user judges the timing correctly (there will be a reasonable margin for error here) then the game continues...
Watch this space...