[PD] Motion Detection Strategies - Gem

Hi everyone,

I bought a cheap Logitech webcam to try motion detection with PD+Gem. I'm considering, among others things, using this as part of a digital instrument design.

First of all, the cheap webcam is of course rather noisy. But, the motion detection doing:

[pix_movement 0.3] l [alpha] l [pix_blob]

definitely does seem to work okay.

I did a test using the X and Y to control FM synthesis however, and it mostly worked but tended to produce a lot of noise when something was moving. What is the recommended way to smooth out the signal a bit?

Also, best way to find the average speed of motion?

Finally, are there more advanced motion detection strategies? Like, say, could I somehow put a bright red dot on my index finger, and just detect where my index finger is? I'd love to hear what people have done.

I also wonder, how the hell I would set it up for a real performance - Experimental music concerts here tend to be in small alternative sorts of venues, with not much space.

~David