andi

There's a link to the Rust source in the post above actually (here). I basically wrote a program that loads in an mp3, cuts it up into 1/30th-second chunks, feeds each one-seventh of a second into the realfft crate and draws the resulting FFTs as colors in a series of PNGs. I think there's a lot of things you're supposed to do when converting an fft to a spectrogram but I only did some of them, mostly I intentionally left it kind of rough. The left channel's FFT is drawn vertically in red and the right channel's FFT is drawn horizontally in blue, and the green channel goes high when the two overlap. I was originally going to have the FFT as a square in the center and have conventional waveforms mirrored on the edges, but then I tried rotating it forty-five degrees and I decided I liked the resulting "wings" so much I was like ok stop there. To me the trick to making good generative art is knowing when the numbers have given you a gift.

Rotating the display 45 degrees turned out to be the hardest part. I was like "this would be incredibly easy with matrices but I do not need matrices, it will be simple to write out the equation by hand". But then it was not simple.