The Johns Hopkins Gazette: April 10, 2000
April 10, 2000
VOL. 29, NO. 31


Gotcha! APL Enhances Video Surveillance

By Ben Walker
Applied Physics Laboratory
Johns Hopkins Gazette Online Edition

In Hollywood, it's easy: A young techie stares at a blurred image on a monitor. He taps a few keys. The blur becomes a recognizable face. "That's our guy!" he yells. Cut to a car chase.

In the real world, it takes someone like Nick Beser, working in APL's Shipboard Systems Information Research and Interpretation Systems Laboratory, to make that happen. Beser, of the Power Projection System Department, leads a number of APL Independent Research and Development projects aimed at manipulating video images to extract the maximum amount of useful information for crime fighters. "Video is a major law enforcement weapon offering immediate photographic evidence," Beser says. "But right now it's difficult, costly and time-consuming for law enforcement officials to get data they need from videotape."

Beser says that most video surveillance systems are designed to provide situational awareness--what's happening throughout a store, for instance--rather than to identify possible suspects. In large organizations, multiple cameras may be linked together and recorded on a single tape. Time-lapse techniques may be used, and the tape itself may be re-recorded many times. The result is often degraded video--and lots of it--that requires special equipment and advanced skills to find the frames of interest from a vast archive of tape.

Motion poses another problem, according to Beser. "When you shoot from a moving car, you get unstable pictures. And if you add the movement of the object being taped, you can lose a license plate number or other potential crime-solving details."

The Counterdrug Technology Assessment Center of the Office of National Drug Control Policy is developing a real-time video processing system that stabilizes video pictures--removing the movement "noise"--to give analysts a clearer view. But the system, which had been reported to cost approximately $40,000, does not include video enhancement features and requires a forensic specialist to operate it and interpret the results.

"What we need is a low-cost system that provides both video stabilization and enhancement and that can be operated by local police without a lot of training," Beser says.

Beser has proposed such a system. Using research based on his Scene Change Detection IRAD, Beser is working with the Howard County, Md., police force, analyzing videotape from their previous cases to further develop algorithms and refine methods of exploiting video. He has written software that can remove movement noise from videotapes, replacing expensive hardware systems designed to do the same thing. Rob Taylor, of APL's Research and Technology Development Center, is helping by developing computer models of different types of video cameras.

At the same time, Beser is developing a sophisticated set of video enhancement tools that detectives can use to sharpen images, brighten them and zoom in for a closer look. "We're able to provide super resolution by combining multiple low-quality frames into a single high-resolution picture that fills in critical details," Beser says. "With stabilized, enhanced video, police can detect and locate small objects--evidence--thrown from a car during a high-speed chase."

These techniques also have great potential for the military services. The Navy recently asked Beser to analyze field video that captured the premature detonation of a bomb dropped from an aircraft. By pinpointing the precise time of explosion, he was able to assure the Navy that a safety system carried by the bomb had operated properly.

Beser and Taylor are also developing software that can extract 3-D data--for example, the dimensions and relative locations of buildings--from videotape obtained by unmanned aerial vehicles. This data then becomes a reference to which images taken at other times by other cameras, such as those carried by surveillance satellites, can be compared to detect changes.

Back to law enforcement, Beser says his system will be effective at both FBI crime lab and police station levels. Along with a computer, software and a high-quality VCR, the system will include tutorials and "wizards" so detectives can process and interpret video data quickly. "Then," Beser says, "video may play a bigger role in criminal apprehension."