Hello
Two cameras would send their frames to two image stacks which contain say 30 frames (the more the better). The actual frame is subtracted from the last one and the resulting frame of this simple kind of movement-dedection would serve as a parameter to compose from the two stacks the actual video output reading each single pixel in a random manner from the two stacks mixing both by using an appropriate function.
should be possible with stock GEM modules, I did an simular installation with pix buffering and subtraction etc, but a single usb cam. My only concern is connectig 2 cameras, I believe that this gives trouble with any modules but I would like to be proven wrong.
Cheers,
Malte