Wednesday, July 16, 2008

Face Recognition Accuracy

Science Magazine of 25 January 2008 had a paper with a very daring title: 100% Accuracy in Automatic Face Recognition. Can that be true?

The authors used industry standard face-recognition system FaceVACS by Cognitec Systems GmbH in Dresden (Germany), which is made available for free by the genealogy Web site My Heritage run by My Heritage Limited in Tel Aviv (Israel). Actually, what is made available for free is the retrieval of faces of celebrities.

When they presented the system with the face of a celebrity, they got a hit rate of 54%. They achieved the 100% hit rate by averaging together 20 images of the celebrity and using that average for the query. The averaging smoothens out the image quality and wide range of lighting conditions, facial expressions, poses, and age.

I happen to have 2 portraits of myself taken by HP under very similar conditions, with the only variable being the aging from 8 years of work in the trenches. Not being a celebrity, I am not in My Heritage's database, but I was nevertheless curious to see if the two portraits match up with the same celebrities — of course also aged by 8 years.

From the Jenkins & Burton paper I would expect that any look-alike better than 54% must be acceptable. So here is the first experiment:

I am not familiar with celebrities, so I do not know if the hits are good or bad, but from left to right they are: Howard Dean 67%, Joe Rogan 64%, Cab Calloway 63%, Tony Danza 63%, Ryo Nishikido 62%, Alizee 57%, Kian Egan 57%, Audrey Tautou 54%.

Puzzling. Maybe it is just garbage in – garbage out. Anyway, in the 8 years I did not have plastic surgery and my physiometrics have not changed, so I would expect to get the same answer with the second image. Instead, I get a completely different line-up.

From left to right the look-alikes are: Cillian Murphy 72%, Barry Williams 70%, John von Neumann 66%, Alan Turing 66%, Matt Leblanc 60%, Leonardo di Caprio 60%, Walter Matthau, 59%, Chloe Sevigny 59%.

Speaking of garbage in – garbage out, in this second query I know two of the celebrities by reputation, and I am quite sure that John von Neumann and Alan Turing are not mono-zygote twins, as the results would suggest.

100%, but lots of research still remains to be done. Roll up your sleeves and back to work!