Sorry, it might be a bit confusing if you're not used to github.

Here is an interactive demo: http://rappdaniel.com/noisy/

I don't get it either. Your demo link just leads to a page with some text boxes on it. I tried it in Firefox and Safari and can't see anything that looks "noisy". I tried changing some of the parameters but that just crashed Firefox.

Increase the opacity and look at the background.

It wasn't github. It was the fact that, at first blush, Noisy seemed to fail the actually-does-something test.

It turned out not to be so, but it did take me a lot of control wiggling to figure out what was going on.