Finding Faces in the e-Crowd

A Swedish startup's search technology aims to ID people in Web photos

A picture may be worth 1,000 words, but when you use words to search for pictures on the Net, the result is often worthless. Just try looking on Google Images for, say, photos of your kids. Maybe you'll find one or two shots on a photo site, if you use such services. But you're just as likely to get a collection of random photos. (Searching for BusinessWeek's Paris bureau chief yielded pictures of Dick Cheney, a UFO, and Buddha.)

Nikolaj Nyholm, 32, thinks he can do better. He's the CEO of Swedish startup Polar Rose, a new advertising- supported service that provides software tools for image search. The programs —browser "plug-ins," in geek-speak—hunt for pictures based on what they depict, not just on the titles or captions attached to them. And, in an unusual twist, Polar Rose uses its own community of "beta testers" to help label photos in databases.

The results are both startling and, to some people, alarming. Identifying people's faces on public photo sites and other Web pages without asking permission opens "a huge can of worms," says Lee Tien, a lawyer with the Electronic Frontier Foundation, a civil liberties group in San Francisco. "It has a lot of dangerous potential."

Before joining Polar Rose in 2006, Nyholm built companies to streamline the registration of Net domain names or help people share Wi-Fi connections securely. Approached by venture capitalists to advise Polar Rose on face-recognition, Nyholm signed on as CEO—partly because he was intrigued by the challenge. Humans excel at spotting people they know in pictures, regardless of the lighting or angle of the face, but computers are easily flummoxed. Polar Rose addresses part of the problem by extracting a virtual 3D portrait from a single two-dimensional photo, then using that to recognize the same face in other photos.


That's fine, as long as the original photo is labeled. But what about the millions of unidentified faces in pictures scattered across the Net? Polar Rose tackles that with the proverbial wisdom of the crowd. Users of its software constantly confirm and correct the program's search results—much as readers spot errors in Wikipedia articles.

Users also can make their own photos available online, which Polar Rose can then compare with millions of others. For example, if your wedding pictures with all the guests are online for all to access, you may suddenly be able to find other shots of the same people elsewhere on the Net. And the names? Nyholm says Polar Rose's 1,800 beta testers are already viewing and verifying a half-million photos a day, and spotting people they know in about 3% of the pictures they see. So the database of confirmed identities is growing fast.

Polar Rose expects to launch the service in 2008. It has a deal with Yahoo (YHOO)'s Flickr site that will allow members to tag photos in their personal albums. Polar Rose will separately introduce a product that lets any Web site—from blogs to large social networks—offer the same capability by adding a few lines of computer code to each page. Down the road, any visitors looking at photos on such sites will be able to request identities of the faces they see there.

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