A method gathers scene information from a low-cost camera system. Existing surveillance systems using sufficient cameras for continuous coverage of a large field necessarily generate enormous amounts of raw data. Digitizing and channeling that data to a central computer and processing it in real time is difficult when using low-cost, commercially available components. A newly developed system is located on a combined power and data wire to form a string-of-lights camera system. Each camera is accessible through this network interface using standard TCP/IP networking protocols. The cameras more closely resemble cell-phone cameras than traditional security camera systems. Processing capabilities are built directly onto the camera backplane, which helps maintain a low cost.

The upper half of the figure depicts a String-of-Lights Camera System installed to observe multiple physical spaces with arbitrary overlapping views. The lower figure presents block diagram of major components within a single camera.
The low power requirements of each camera allow the creation of a single imaging system comprising over 100 cameras. Each camera has built-in processing capabilities to detect events and cooperatively share this information with neighboring cameras. The location of the event is reported to the host computer in Cartesian coordinates computed from data correlation across multiple cameras. In this way, events in the field of view can present low-bandwidth information to the host rather than high-bandwidth bitmap data constantly being generated by the cameras. This approach offers greater flexibility than conventional systems, without compromising performance through using many small, low-cost cameras with overlapping fields of view. This means significant increased viewing without ignoring surveillance areas, which can occur when pan, tilt, and zoom cameras look away. Additionally, due to the sharing of a single cable for power and data, the installation costs are lower.

The technology is targeted toward 3D scene extraction and automatic target tracking for military and commercial applications. Security systems and environmental/vehicular monitoring systems are also potential applications.

This work was done by Lawrence C. Freudinger of Dryden Flight Research Center and David Ward and John Lesage of SemQuest, Inc. For more information, contact SemQuest, Inc. at (719) 447-8757. DRC-007-022