Jeez, that's a long ass article to just end up at the tl;dr of: FFT - fast fourier transform. I've used such tools with mixed results on older scanned photograp

Jeez, that's a long ass article to just end up at the tl;dr of: FFT - fast fourier transform. I've used such tools with mixed results on older scanned photographs. You can pull it off in GIMP and one or two extensions, I believe. https://www.gimp-forum.net/Thread-Fourier-Transform-tutorials https://www.gimp-forum.net/Thread-Fourier-Transform-tutorial...