Because of reasons, I recently needed to get a greyscale image and randomize the values of the different greys in the image. I couldn’t be bothered doing it all by hand, so I wrote another mini tool to do it for me.
This tool will get all the different greyscale values in your image and replace them with new randomized ones. It can be used to make lots of permutations of greyscale images, in case for some reason you ever wanted to do that.
Download the tool here.