stained canvas generation

I've tried to stain the programs canvas but it just ends up looking like smears. Anyway how possible would it be to randomy generate stained canvases with like a selected color? Reseting random generated canvases until you see the one you want could help get the mind going on where to start in my opinion. Here's an example I found online.

I want to explain further I thought this could kinda be done by some kinda noise generation in varying oppacities and would use the color you have selected as your primary color. For instance this would be brown in the example.