 that the computer detects a potential event and shows it to the operator who then decides what to do, SO we are still a long way from machines replacing humans," he says. 7.4.5 Smart Surveillance Camera Software As we walk down streets, across parking lots, and through airports, cameras are watching us. But who's watching the cameras? In many instances, nobody. The cameras often simply serve as tools to record a scene. Nobody looks at the video unless a crime or other important event occurs. This situation may soon change. Computer science researchers at the Uni- versity of Rochester are looking to make surveillance cameras more useful by giving them a rudimentary brain. "Compared to paying a human, computer time is cheap and getting cheaper," says Randal Nelson, an associate profes- sor of computer science and the software's creator. "If we can get intelligent THE SEEING EYE machines to stand in for people in observation tasks, we can achieve knowl- edge about our environment that would otherwise be unaffordable." Far from being an electronic "Big Brother," Nelson's software would only focus on things it was trained to look for: like a gun in an airport or the absence of a piece of equipment in a lab. Nelson has even created a prototype system that helps people find things around the house, such as where the keys were left. In developing the technology, Nelson set about experimenting with ways of differentiating various objects in a simple black-and-white video image, the kind created by most surveillance cameras. The software first looks for changes within the image, such as someone placing a soda can on a desk. The change is immediately highlighted as the software begins trying to figure out if the change is a new object in the scene or the absence of an object that was there earlier. Over time, other methods have been developed, such as matching up background lines that were broken when an object was set in front of them. A later version of the software, which works with color cameras, takes an inventory of 