[PD] Motion Detection Strategies - Gem

David Powers cyborgk at gmail.com
Fri Oct 6 20:52:07 CEST 2006

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]

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

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.


More information about the Pd-list mailing list