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Check out this really cool video by Alex Schlegel created using a really simple feedback loop with a webcam, computer, and projector (no extra graphics processing):

Video experimenting with the feedback-induced patterns a webcam creates when viewing its own feed projected onto a wall. I connected a 1080p digital projector to my laptop and projected the laptop’s display onto a wall (the image was about 6ft. across). Next I connected a cheap webcam to my laptop and positioned it facing the wall, roughly centered on the projection, approximately 5ft. away, and as high as I could without casting a shadow on the projection. I started the webcam’s test program (the webcam seems to refresh at about 10-15Hz), maximized the window, and then filmed the wall using a digital video camera placed on a small tripod on top of the projector. As I filmed I experimented with different modes of mouse movement (freehand, circle, figure-eight, zig-zag, and random). I used Windows API calls from a program I wrote in Visual Basic to control the automatic mouse movements.

becky stern headshot Trippy visuals from mouse cursor visual feedback

Becky Stern

Becky Stern is director of wearable electronics at Adafruit Industries. Her personal site:

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