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Comment by japhyr | Hacker News Reader

Wow! I had no idea this could be done. The implications of this technique for forensics work are intriguing.

Is this a new idea, or have people been working on this for a while?

The idea of examining a subject's pupil has been around for years. I've used a similar technique to reverse engineer lighting setups for portraits. See my friend Mike's portrait of one of his children:

http://www.flickr.com/photos/oatmeal2000/8545400550/sizes/o/

You can clearly see that he uses one umbrella to the right of the camera. With higher resolution images and better focus you can sometimes determine the brand of lighting they use, but that's only if it has a very distinctive shape.

This 2004 paper got a lot of attention in the computer vision community doing essentially the same thing about a decade ago:

http://www.cs.columbia.edu/CAVE/projects/world_eye/

"The World in an Eye," K. Nishino and S.K. Nayar, IEEE Conference on Computer Vision and Pattern Recognition (CVPR), Vol.I, pp.444-451, Jun, 2004.

There was a related paper on using the eyes as a means of capturing a full environment map which could be used directly for relighting a scene (e.g., for 3d rendered scenes or for compositing digital objects into scenes):

http://www.cs.columbia.edu/CAVE/projects/eyes_relight/

Well it is in many crime movies except that our megapixels were not enough for such uses. Now with high resolution images it is relatively easier to do. I'm not surprised by it. It just is another use of tech.

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