A way to create random-noise background image (png) with javascript?

Question

The new layout of YouTube added a background random-noise which I like very much, having seen almost exactely the same effect on other sites, so I plan to use the same technique

Answer 1

Fyi: Base64 is binary data represented as a string. Most likely the original image still came out of Photoshop and was later encoded into Base64. This technique helps having less http-requests per page view, as the actual image data can be saved and cached inside the css or html document.