Structural hashing for pixel art: a 1024-byte key that answers 'is this the same artwork? ' in 115 nanoseconds — and then tells you exactly what was edited. Nine days, or one second.
Source: [Dev.to](https://dev.to/matias_affolter/how-we-made-image-copy-detection-1000000x-faster-by-refusing-to-look-at-pixels-3c50)