Yossam :
I'll try to put something together and post it in file sharing. Because the original photo by itself isn't strictly a proper density mask, and has light and shade elements that aren't necessarily related to its density, (maybe even the opposite of density), I needed to massage it in an image editor to block out the ground for one thing, and make it more just a black and white representation of the density of the clouds. This was a by guess and by gosh, trial and error process.
