A search engine that uses sophisticated facial recognition to allow users to identify and find people in online images will launch next month. But civil liberties groups say the biometric-style tool could compromise the privacy of anyone who has their picture online.
Search engine Polar Rose reconstructs the 3D shape of a person鈥檚 face and then combines that with characteristics of their features to generate a unique 鈥渇ace print鈥�. This can then be used to search other photos for a match.
In January users will be able to download a plugin for their browser that allows users to enter information about faces they recognise in online images. This data is then sent to a central server allowing anyone looking at an image containing that particular face print to tell who it is. Users can also search the web for more photos containing that face.
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Online image search engines usually work much like their text counterparts. 鈥淭hey find images on pages that contain the words you search for,鈥� says Jan Erik Solem, whose PhD project at Malm枚 University College, Sweden, led to the new company. 鈥淪earch engines are blind to images, Polar Rose is not.鈥�
Third dimension
鈥淪ome biometric companies are using 3D laser scans of faces to aid identification from photos,鈥� Solem says. 鈥淲e鈥檝e developed a way to work backwards; we can create a 3D model of a face from a 2D image.鈥�
That allows Polar Rose to recognise people even when the pose or lighting has changed, he says. The technique was developed using a database of around two thousand 3D face-scans paired with normal 2D photos.
鈥淲e used statistical methods to work out the relationship between the two,鈥� explains Solem. .
Broadband explosion
The 3D shape is combined with colour and shape data from the 2D picture to generate the face print that serves as a unique identifier.
Solem says he cannot give figures on the search engine鈥檚 accuracy until it is tested by the public. It works on any image with a face at least 100 pixels (35 millimetres) across, as broadband becomes more common, more and more pictures will fit the bill, he predicts.
Earlier this year, another visual search engine called Riya launched. It has a less biometric approach, instead relying on the context of a person鈥檚 face 鈥� such as clothes and objects around them 鈥� to search images for a specific person.
Privacy concerns
Polar Rose and future developments that make facial recognition available to the masses risk encroaching on people鈥檚 privacy, warns Yaman Akdeniz, director of the UK non-profit group Cyber-Rights & Cyber-Liberties.
鈥淎lthough this sounds like a great idea, I would not like to be searchable in this way, or so easily tracked without my consent,鈥� says Akdeniz. The database compiled by Polar Rose is similar to the kind of biometric database some governments wish to use, he points out.
鈥淚 wonder whether they have a right to build such a database,鈥� says Akdeniz, he suggests people think twice before embracing such potentially intrusive tools, and consider which photos of themselves they allow online.
Others agree. Simon Davies, director of the campaign group Privacy International and a specialist in technology and privacy at the London School of Economics, UK, says face-searching technology is valuable but must be used responsibly.
He fears Polar Rose could help identity thieves or stalkers, or even be used by the police to monitor protesters. 鈥淭hey could use the service to find where people have been, what their activities are, or who they associate with,鈥� he says.
Search engines should allow users to prevent their photos being searched, says Davies. 鈥淭here should be a way to put code in a webpage that signals you want to opt out,鈥� he told New 杏吧原创.
