Base64-Noise-Generator is a small web tool to create base-64 CSS background noise images as PNG.
Colors and intensity as well as the dimensions of the image are freely configurable. By default 8-bit color depth is enabled – you can change it to 24-bit image, but it is not recommended to do so:
the 8-bit flavour is less than half the size most of the times. And also there is no way to blend from one color into another with more than 255 steps (in 24-bit colors). So the quality of the images is the same.
The randomness is not quite perfect. Ideas for improvements are very welcome. But I think you can already get useful results if you adjust the values and generate certain times until you get a nice look.
Update: The full source code of the tool is available on Github.