Recreating the spectrogram face

I made something like that, too, but it's not currently online and just a short derpy chip-ish tune anyway.. though the image I embedded was little heart shapes, and they went nicely with the music, so there's that haha.

I used this for it: http://victorx.eu/BitmapPlayer.htm To imagine we can that with moving images in the browser now, well, whoa.

This is what RDJ used to make the sounds in the b-side on Windowlicker.

Yes, the FFT/STFT[1] is generally invertible, potentially subject to knowing the parameters it was generated with, or finding some reference markers in the original input you could use to derive them.

There's also the possibility the spectrographic image itself might be a lossy representation of the actual frequency domain data, in which case you won't get a perfect result back out. Probably recognisable though.

If I had time I'd do some flubbing with octave/scipy and demonstrate it, but alas, the margins of this weekend are too small, etc, etc.

[1] https://en.wikipedia.org/wiki/Short-time_Fourier_transform#I...

The Discrete-Time Fourier Series is invertible. The problem is that for each pixel the Fourier series is a complex number and what is plotted is the magnitude (so the phase is not shown). Reconstructing a signal from only the magnitudes of the Fourier coefficients is ill-posed, i.e. there are multiple signals with the same Fourier coefficient magnitudes.

Still there is active research on reconstructing signals from only the Fourier magnitudes (under several assumptions). This is called the 'phase-retrieval problem'. http://en.wikipedia.org/wiki/Phase_retrieval

Aphex Twin has made some softer songs as well, a popular one being this: https://youtube.com/watch?v=iiZEto2j2GQ

His newest album Syro also has less aggressive tracks, but it seems to not be on YouTube.

Don't be a jerk, please.