Security in 3D: Coming Soon to an Airport Near You?

Security engineers left and right have been attempting to crack the code on technology to match CCTV photos of faces with image archives in order to capture known criminals and thieves. Recent research out of Arizona State and Michigan State show that 3D laser scans could be eventually utilized to alleviate problems with lighting and photos angles in public areas with fast moving crowds.


Using a newly developed program, Dirk Colbry from ASU and his MSU colleague, George Stockman, performed 300 laser scans of 111 different faces using a commercial scanner to store images, while a horizontal plane of laser light passed over the subject's face. These images were then manipulated to create 3D models of each person's face.

The results were superb-- with the new system, different scans of the same face were matched even when lighting was unusual or the angle from which the images were taken was off by as much as 30 degrees. The error rate was a startling one percent.

This research demonstrates a new step in the advancement of surveillance technology, although its implementation will need to overcome the high price, slow scan speed and short-range sensors that may serve as roadblocks. The current scanner price of $50,000 needs to drop to about a tenth of that price to encourage widespread deployment. Additionally, scans currently take 2 to 5 seconds, making the technique obsolete in large crowds and only functional at choke points, such as airport and train station security checkpoints, where passengers are forced to wait in queues and in close range of scanning devices.

Being able to accurately identify someone who has paused, short-range, at a checkpoint and presented thier face, or iris, or fingers, or hands to the confidence levels demonstrated here has been possible for quite some time. But sometimes it's hard for me to get too excited about most of those approaches. That's because what we would all like to get out of any new biometric systems that get deployed at the airport are shorter lines and fewer checkpoints not more!

At 3VR, we're constantly looking for new algorithms to improve our facial recognition analysis features to combat the disparities in expression, lighting and angle. But to date, we have limited ourselves to writing algorithims for use in conjunction with conventional video cameras. That's because CCTV, and even new IP camers, are cheap, prolific, and offer something that laser scanning systems can't, the ability to work at a distance with uncooperative subjects.

Though current facial surveillance approaches fall somewhat short of 99%+ accuracy of 3D laser scanners, I can say that some of the techniques we are pioneering today hold strong promise of closing that gap. By processing streams of facial data from standard CCTV video feeds, it's possible to create an extremely accurate facial model; maybe one that will someday rival 3D scans. When will facial surveillance catch up? I can't say exactly. But, I do know that technologies like what we deploying at 3VR will get there long before a $50,000 laser scanner becomes as cheap as a video camera.