An emerging trend in video surveillance technology could help tip off school leaders to potential acts of theft or violence before they even happen.
Researchers and security companies are developing cameras that not only watch the world but also interpret what they see. Soon, some cameras might be able to find unattended bags at airports, guess your height, or analyze the way you walk to see if you’re hiding something.
Most of the cameras widely used today are used as forensic tools to identify perpetrators after the fact. To stop an act of theft or violence before–or while–it occurs, you’d need to be watching the camera at the time. But the latest development in surveillance technology, known as "intelligent video," could transform cameras from passive observers to eyes with brains, able to detect suspicious behavior and potentially prevent crime before it occurs.
Surveillance cameras are common in many cities, monitoring tough street corners to deter crime, watching over parking lots or sensitive government buildings, and even catching speeders. Cameras are on buses and in train stations, schools, and stores. Most feed video to a central control room, where it is monitored by security staff.
The latest innovations could mean fewer people would be needed to watch what these cameras record, making it more feasible to install more cameras throughout a school building or other institution.
"Law enforcement people in this country are realizing they can use video surveillance to be in a lot of places at one time," said Roy Bordes, who runs an Orlando, Fla.-based security consulting company. He also is a council vice president with ASIS International, a Washington, D.C.-based organization for security officials.
The advancements already have been put to work. For example, cameras in Chicago and Washington can detect gunshots and alert police. Baltimore installed cameras that can play a recorded message and snap pictures of graffiti sprayers or illegal dumpers.
In the commercial market, the gaming industry uses intelligent camera systems that can detect facial features, according to Bordes. Casinos use their vast banks of security cameras to hunt cheating gamblers who have been flagged before.
In London, one of the largest users of surveillance, cameras provided key photos of the men who bombed the underground system in July 2005 and four more who failed in a second attempt just days later. But the cameras were only able to help with the investigation, not prevent the attacks.
Companies that make the latest cameras say the systems, if used broadly, could make video surveillance much more powerful. Cameras could monitor airports and ports, help secure schools and homes, and watch over vast borders to catch people crossing illegally.
Intelligent surveillance uses computer algorithms to interpret what a camera records. The system can be programmed to look for particular things, like an unattended bag or people walking somewhere they don’t belong.
"If you think of the camera as your eye, we are using computer programs as your brain," said Patty Gillespie, branch chief for image processing at the Army Research Laboratory in Adelphi, Md. Today, the military funds much of the smart-surveillance research.
At the University of Maryland, engineering professor Rama Chellappa and a team of graduate students have worked on systems that can identify a person’s unique gait or analyze the way someone walks to determine if he is a threat.
A camera trained to look for people on a watch list, for example, could combine their unique walk with facial-recognition tools to make an identification. A person carrying a heavy load under a jacket would walk differently than someone unencumbered, which could help identify a person hiding a weapon. The system even could estimate someone’s height.
With two cameras and a laptop computer set up in a conference room, Chellappa and a team of graduate students recently demonstrated how intelligent surveillance works.
A student walked into the middle of the room, dropped a laptop case, then walked away. On the laptop screen, a green box popped up around him as he moved into view, then a second focused on the case when it was dropped. After a few seconds, the box around the case went red, signaling an alert.
In another video, a car pulled into a parking lot and the driver got out, a box springing up around him. It moved with the driver as he went from car to car, looking in the windows instead of heading into the building.
In both cases, the camera knew what was normal, the layout of the room with the suspicious bag, and the location of the office door and parking spots in the parking lot. Alerts were triggered when the unknown bag was added and when the driver didn’t go directly into the building after parking his car.
Similar technology is currently in use by Marines in Iraq and by the subway system in Barcelona, according to ObjectVideo, a Reston, Va., firm that makes surveillance software.
ObjectVideo uses a "tripwire system" that allows users to set up virtual perimeters that are monitored by the cameras. If someone crosses that perimeter, the system picks it up, sends out an alert, and security staff can determine if there is a threat.
Company spokesman Edward Troha predicts the technology, currently designed primarily to protect borders, ports, and other infrastructure, could be adapted to help prevent theft or guard private homes.
The Jacksonville Port Authority uses ObjectVideo software as part of its security measures to watch the perimeter of the Florida port that handles 8.7 million tons of cargo and thousands of cruise ship passengers each year. The surveillance system sends real-time video from anywhere at the port of possible intruders to patrol cars.
Intelligent surveillance also has huge implications for schools, says Keith Drummond, chief executive of Houston-based video surveillance firm LenSec LLC.
"Schools often have the challenge of stopping vandalism, theft, and more serious crimes that involve drugs, weapons, and violence," Drummond said. "A video surveillance system that has intelligent features can actively search for behavior that often occurs just before these types of crimes occur. For example, loitering in certain areas often is a sign of a pending drug sale. A gathering crowd is often the sign of a fight or other violence. A person entering an unauthorized area is typically a warning of theft or vandalism."
He concluded: "The use of intelligent video will allow administrators and law-enforcement officials to receive alerts containing advanced notification of suspicious activity."
Video intelligence is currently available in two ways, Drummond said: embedded in the camera itself, or as server-based software. "If a customer requires intelligent features, we provide the additional software preloaded in the total solution," he said. "If an existing customer wants to upgrade a non-intelligent system that was previously purchased, we simply add the software to that system."
Still, industry officials say the technology needs to improve before it can be widely used. There are liability issues, such as if someone is wrongly tagged as a threat at an airport and misses a flight, said Bordes. Troha warns that humans are still essential to intelligent video–to tell, for example, if a person in a restricted area is a danger or just lost.
And the cameras can only see so much; they can’t stop some threats, like a bomber with explosives in a backpack. They can’t see what you are wearing under your jacket yet.
"That is an eventual goal, but we’re not there yet," said Chellappa.