3 ms·
> I mean, an iris is like 1cm wide, can you really get a detailed image from 100m away, while the person is walking, looking around, blinking etc.? I assumed t
by Tade0 3y ago
> I mean, an iris is like 1cm wide, can you really get a detailed image from 100m away, while the person is walking, looking around, blinking etc.?
I assumed there would be an appropriate setup for that.
In any case systems collecting iris data en masse from 6m were available a decade ago. Ultimately it's just a photo in near infrared, nothing fancy.
The whole reason why this even works is that the iris as a modality has an unrivaled 240+ bits of entropy, so even partial or blurred images yield enough information to identify a person(requiring 60bits at most).
On top of that it's an extremely stable feature. Shabrat Gula was famously identified after almost 20 years, despite being a child when her photo was taken.
- 4ggr0 3y agoThanks for the interesting answer, lots of things I want to google now! :D
- Tade0 3y agoIf you want to learn more, I recommend a paper by John Daugman - inventor of the encoding system used to store and verify iris data: https://www.robots.ox.ac.uk/~az/lectures/est/iris.pdf https://www.robots.ox.ac.uk/~az/lectures/est/iris.pdf By far the largest database of irises is the one created by India’s Unique Identification Authority, with more than a billion people enrolled: https://www.irisid.com/indian-national-identity-program-tops-one-billion-enrollees-2/ https://www.irisid.com/indian-national-identity-program-tops...