Professional Engineering: 'Face to Face'

11 March 2009

Identification using biometrics is a growing industry and facial recognition shows the greatest potential of all, writes Lee Hibbert

A passenger on a flight into Heathrow fires up his laptop with his fingerprint. When he lands, he avoids the queues at passport control by using an iris-scanning system to confirm his identity. And when he gets to his place of work, he gains access to the building through the use of a facial recognition machine.

All these identification technologies already exist and are commercially available, of course, but it is facial recognition technology that is most exciting the industry. As the least intrusive it has enormous applicaton potential as well as being quick.

The use of biometrics, the identification of people by measuring some aspect of their individual physiognomy, is becoming increasingly widespread in public life. And with fingerprints due to be included on any new national identity card scheme, it would seem that biometrics is here to stay.

"Biometric applications have increased dramatically since their first deployment in the 1970s," says Prof James Wayman, a research administrator with San Jose State University in the US, and one of the world's leading experts in biometrics. "Establishing the business case for their use has been difficult in nearly every single deployment. But the application of biometrics will become ubiquitous over the next couple of decades."

Early applications suffered from reliability problems. Many of those technical issues, such as the problem of variable lighting conditions having an impact on the accuracy of facial recognition systems, have been overcome by significant research and development efforts. The sector is still relatively small - that's not because the systems aren't proven, but more because their adoption requires a leap of faith and a considerable upfront investment.

"In the commercial sector it's quite risky to be the first person to introduce the technology. If it goes wrong, your job is on the line," says Hugh Carr-Archer, chief executive of Aurora, which claims to be one of Britain's foremost biometrics company. "There is a natural and understandable reluctance to take a gamble. You've got to be brave and you've got to be persuaded of the commercial benefit of the technology to be adopted."

In the public sector, meanwhile, he says that it has been hard to get the government to think about biometrics in a consistent manner. "That is changing now - we are seeing the first signs of better quality planning starting to emerge. But as ever with these government projects, there is a long gestation period before the award of any contract and it can prove a big financial risk for the smaller firms."

Aurora has been successful in selling its facial recognition systems to the construction sector. The technology has allowed some of the world's biggest building firms to cut down dramatically in employee fraud - workers claiming to be on site but actually getting someone else to sign in for them. Facial recognition is seen as having a number of benefits over other biometrics technologies: it is contactless, it is non-intrusive and it is absolutely guaranteed not to produce a 'false-positive', meaning that no unauthorised personnel can get past it.

Aurora's technology works by using the eyes as the main reference point. It then takes thousands of other data measurements, employing a series of complex algorithms to build up a highly accurate representation of the face. Carr-Archer says that once a user is scanned and registered on the system, he or she will be recognised next time around in a matter of seconds.

"It's and incredibly fast process," he says. "The responsive software 'finds' the user's face within a frame and starts making comparisons instantly. Sensors don't need to be adjusted for height; spectacles don't need to be removed; operatives don't need to touch a scanner or present their face in a particular way. Overall, the verification process takes approximately 1.5 seconds."

Aurora's system gets round the problem of variable light by bathing the face for a split-second in an invisible infra-red flash. This, says Aurora, means that the system works perfectly in any condition, from bright sunshine to pitch dark.

Aurora's facial recognition technology was successfully used to allow hundreds of workers to gain daily access to Heathrow's Terminal 5 during its lengthy construction phase. "It proved an excellent way of enforcing security and reducing fraud," says Carr-Archer.

He also expects to see the system widely adopted in schools and colleges, where he thinks it could improve student safety while freeing up teachers from the task of morning and lunchtime registration.

Another British company, Surrey-based OmniPerception, is also at the forefront of facial recognition systems, particularly in the area of crime reduction. It recently supplied technology to Hertfordshire police for installation in a new 40-cell custody suite. Officers at the facility wanted to be able to take good quality images of those in custody, and have an accurate method of identity verification when suspects are arrested. The system effectively prevents known offenders from claiming to be someone else.

OmniPerception is also working on a £1.6 million project with defence giant BAE Systems to add lip movement and speech pattern recognition to exisiting face recognition technology. This would offer law enforcers new ways of securing valuable evidence about a suspect's identity and activities from CCTV images. The research will also take forward new advanced face-finding and tracking technology for use with CCTV footage.

David McIntosh, chief executive of OmniPerception, says that facial recognition has a greater role to play in the security sector.

"The full potential of CCTV as a defensive security measure and as an investigative tool has yet to be realised," he says. "One of the keys is better automation - making things faster and more accurate."

The work with BAE Systems will aim to expand the parameters in which facial recognition systems can work. At present, faces can be scanned as long as the user stands within plus or minus 8º straight on to camera. McIntosh thinks that that could be developed to as much as plus or minus 45º, allowing far more people to be tracked.

His comapny is also looking at how facial expressions such as smiling or frowning affect the accuracy of recognition and at being able to recognise people from greater distances, anywhere up to 100 metres.

"Football clubs are interested in this sort of technology for the surveillance of crowds. They want to make sure that it is the season ticket holder who is actually sitting in their allocated seats. Clubs lose a lot of money through the transfer of tickets," he says.

OmniPerception has also had success supplying its technology to banks, with one financial institution in London's Canary Wharf business complex using its facial recognition system to provide biometric control of key doors and entry points. McIntosh says the bank considered several biometric alternatives, but chose facial recognition because it was deemed highly accurate, easy to use and unobtrusive.

"Facial recognition is about making people feel more secure without becoming a totalitarian regime," he says. "Other technologies - such as fingerprinting - have criminal connotations and people don't like using them. With facial recognition, you just stand there, point your face, and it's done."

The biometric industry acknowledges that in general terms it still has some way to go before it can claim widespread acceptance of its technologies. The process has not been helped by recent high-profile cases on non-biometric personal data being lost - mainly by government agencies.

Carr-Archer of Aurora recognises that some people are still suspicious of biometrics and would not be keen to supply any form of anatomical detail. "The loss of laptops and memory sticks has been used by certain lobbies to whip up what I perceive as an exaggerated fear of biometrics," he says.

"The public needs more reassurance but already many people can see the value in a properly administered biometric system."