Here's a somewhat easier, but more limited implementation that some Microsoft researchers published back in '99: The VideoMouse: A Camera-Based Multi-Degree-of-Freedom Input Device http://citeseer.ist.psu.edu/301249.html
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Here's a somewhat easier, but more limited implementation that some Microsoft researchers published back in '99:
The VideoMouse: A Camera-Based Multi-Degree-of-Freedom Input Device
http://citeseer.ist.psu.edu/301249.html