Fighting crime hasn't been the only success for video surveillance. One autumn day in Brittany, France, 18-year-old Jean-Francois LeRoy was swimming in a 25-meter public swimming pool. He was practicing holding his breath for long periods of time when he suddenly lost consciousness the human lifeguards watching the pool didn't realize what was happening as LeRoy sank slowly and quietly to the bottom of the pool. Without help, it would have taken him as little as four minutes to die. Although no human lifeguard saw LeRoy drowning, 12 large machine eyes deep under the water were watching the whole incident, relaying the images to central computer nine months earlier, a modern electronic surveillance system called Poseidon had been installed. Poseidon covers a pool's entire swimming area, and able to tell when swimmers are not moving the way they are supposed to. When the computer detects a problem, it instantly activates an alarm to alert lifeguards and displays the exact location of the incident on a monitor. Just 16 seconds after Poseidon noticed LeRoy sinking, the lifeguards pulled him from the pool and gave him CPR He started breathing again, and after one night in the hospital was released with no permanent Poseidon had saved his life