Some updates:
I might stick to video after all. Last week I was fooling around with the Robo Realm software, and I tried out the
Sobel Filter on the webcam output. Quite an interesting edge detection filter.. might be useful for the terrain analysis
Sobel operator - Wikipedia, the free encyclopedia
Probably need to work out the optimum angle of the gradient sweep.
Another thing to consider with video streaming is the noise.. perhaps just using a median filter is enough?