I've just tried it on the WiFi light painting video posted here last week (http://news.ycombinator.com/item?id=2270878 http://news.ycombinator.com/item?id=22708

I've just tried it on the WiFi light painting video posted here last week (http://news.ycombinator.com/item?id=2270878 http://news.ycombinator.com/item?id=2270878) and it worked fine. You need to stop the video first, run the script, and then you're good to go.