An Interactive Introduction to Fourier Transforms
Another cool FFT + image use:<p><a href="https://www.youtube.com/watch?v=yyox358zIRw" rel="nofollow">https://www.youtube.com/watch?v=yyox358zIRw</a><p>You can use FFT principles to isolate and remove repeated patterns in images (such as the patterns created by those textured papers of old photographs).<p><a href="https://www.3d4x.ch/Swift's-Reality/FFT-Photoshop-plugin-by-Alex-Chirokov/16,35" rel="nofollow">https://www.3d4x.ch/Swift's-Reality/FFT-Photoshop-plugin-by-...</a><p>I've personally used this in a project and the results are impressive.