distributed under the terms of the GPL license.
I really liked the QC Co-Lab Lightwall project, but I don't have the patience to build a perfectly aligned matrix of lights. So I set out to write some software that can do roughly the same thing, but using randomly placed light instead.
The SoftwareThe software is relatively simple, but took some experimentation to get working. The hardware fairly similar to the QC Co-Lab Lightwall project. I use a teensy to drive the lights, a raspberry pi to drive the teensy and a wifi bridge to get access to it from inside the house. After throwing the lights on the tree (literally!) I put my cellphone on a tripod (using one of these) and ran a webcam program on it, then I ran the acquire program from the tarball below which turns on one light at a time and takes pictures of it. This takes like about 45 minutes for the 300 lights that I have. (currently, I'll probably have more next year.)
After capturing a whole bunch of pictures, I run it through the solve program, which uses a non-negative-least-squares. First it the 7 pictures that go with a particular light (each in a different color), and calculate where in the picture that particular light is. After that, the NNLS algorithm is used again to invert the light->pixel into pixel->light map. This takes about 30 minutes on a fast computer.
The third step is to run some video through the 'video' program. It will read the solution produced in the previous step and do a simple matrix multiplication for each frame/color to map it into light colors. The output file contains the raw data for the lights and could potentially be fed directly to /dev/ACM0 with cat. I usually use the "play" program instead to make sure I initialize the lights properly.
The tarball contains some python hacks for creating the video sequence as well. Beware, there is no readme file or step-by-step instructions, if you can't figure out how it works, you probably don't want to use my software anyways. :)
The DownloadIf you want to see my code, it is available here: chaosdisplay.tar.gz
The CreditsThis project is based on the great work of those who hacked GE color effect lights before me:
The EndProblems? Questions? Suggestions? Mail me at firstname.lastname@example.org.
Last modified: December 16th, 2012 - Design by Monica & Fredrik Hübinette