You can't look at it like _that_. Biometrics has its own "things". I don't know what OP is actually doing, but it's probably not classical image processing. Mos

You can't look at it like _that_. Biometrics has its own "things". I don't know what OP is actually doing, but it's probably not classical image processing. Most probably facial features are going through some "form of LGBPHS binarized and encoded which is then fed into an adaptive bloom filter based transform"[0]. Paper quotes 76,800 bits per template (less compressed) and with 64-bit words it's what, 1200 64-bit bitwise ops. at 4.5 Ghz it's 4.5b ops per second / 1200 ops per per comparison which is ~3.75 million recognitions per second. Give or take some overhead, it's definitely possible. [0] https://www.christoph-busch.de/files/Gomez-FaceBloomFilter-ICPR-2014.pdf https://www.christoph-busch.de/files/Gomez-FaceBloomFilter-I... Cache locality is a thing. Like in raytracing and the old confucian adage that says "Primary rays cache, secondary trash".