Debanding the World
working on FFT-transformed images is quite the dark magic if you don't understand what you're looking at; this is especially interesting when you look at what e.g. H.264 does to images in FFT: <a href="https://sidbala.com/h-264-is-magic/" rel="nofollow">https://sidbala.com/h-264-is-magic/</a> (look at the 2% mask and the resulting image - it provokes a 'this shouldn't be possible' reaction).