Lawrence Livermore National Laboratory

Unmanned aerial vehicles, such as the Predator shown here, use multiple cameras for persistent surveillance. Courtesty of the Department of Defense. Unmanned aerial vehicles (UAVs), such as the Predator and Reaper drones, are rewriting the rules of battle in Iraq and Afghanistan and are being considered for monitoring U.S. borders. Operated by remote control, sometimes thousands of kilometers from the battlefield, the aircraft use multiple cameras to track and destroy the enemy.

A new Livermore computational system is designed to help the Department of Defense and other agencies monitor tens of square kilometers of terrain from the skies, with sufficiently high resolution for tracking people and vehicles for many hours at a time. The system, called Persistics, promises to overcome a severe and growing problem: the overwhelming volume of video data generated by modern overhead imagery.

The Persistics data-processing "pipeline" uses a technique called pixel-level dense image correspondence to stabilize video, eliminate parallax, compress background, and provide unprecedented subpixel resolution of moving objects of interest. The technique permits "seamless stitching," a process that optically combines images from multiple cameras to create a virtual large-format camera, as well as the ability to compare images of the same area at different times and identify what has changed over that period.

For more information, see From Video to Knowledge.