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arcticpenguin
10th March 2003, 09:27 AM
http://www.cnn.com/2003/TECH/ptech/03/10/israel.twins.reut/index.html

Someone has a new algorithm for facial recognition. The article is long on human interest, short on numbers. I'd like to see numbers for false positives and false negatives, along with an analysis of how it handles deliberate obfuscation: fake noses, prosthetic makeup.

Goshawk
10th March 2003, 01:45 PM
Well, if this is how it works:the computer measures the distances between a number of sample points on the facial surface.

The distances are then reconfigured as straight lines in a three-dimensional space, creating a new and abstracted image, or signature, of a human face built on precise mathematical calculations.

Kimmel and the Bronsteins say that this signature is more or less unique to a particular person. ...I would think that if you knew where the sample points were, you'd be able to build up your face, nose, forehead, etc. with putty and so change the shape of it enough to fool the sampling procedure.

And it says this at the end:Ageing, cosmetic surgery, significant changes to facial surfaces such as growing or removing a beard could disrupt the matching process. So. All it would take would be for Mohammed Atta to grow a beard.

arcticpenguin
10th March 2003, 01:47 PM
I think that is one of the alleged benefits of retina scanning; it's pretty much immune to cosmetic changes.

10th March 2003, 02:04 PM
Seems like a simple pair of sunglasses and/or a hat would do the trick.

10th March 2003, 02:23 PM
I've read several statistical papers on the topic of facial recognition that were quite interesting.

I'll see if I can hunt them up.

Dymanic
10th March 2003, 05:52 PM
Saw an article in Discovery (I think) a while back (maybe 2-3 years back) that had cool diagrams on this.

And, also vaguely remembered, some discussion in Pinker's How the Mind Works (?)about how the brain does face recognition--it looks like rather large portions of our perceptive apparatus are dedicated to the task.

HarryKeogh
11th March 2003, 12:19 PM
i saw a great show ( i think on the discovery science channel) this week on tv and one of the segments was of a guy who had brain damage. he lost all ability to recognize faces. everything else was fine with him. he could only recognize his wife of 20 years by the clothes she was wearing. (another person lost the ability to recognize movement, too freaky!)