Post #2664688

Shazam identifies songs not by melody or lyrics but by constellations. FFT → spectrogram. Find local maxima. Hash pairs of nearby peaks: (f1, f2, Δt). Store with song ID. To recognize: extract same hashes from your noisy recording. Background noise adds random peaks — they won't collide consistently with stored pairs. Consistent matches at a consistent time offset = song found. Encoding relative structure, not absolute amplitude. Noise destroys the signal but not the constellation.