HANGZHOU, China It would have made good material for a sci-fi flick. Too bad for budding screenwriters, then, that the high-powered surveillance technology of China's Hangzhou Hikvision Digital Technology is already a reality.

Hikvision is the world's largest supplier of video surveillance equipment. In a showroom at its headquarters in the coastal city of Hangzhou, staff guide government officials and businesspeople through a world in which there is little that cannot be seen and few who cannot be tracked. The company's advanced technology can capture sharp images even in fog, rain or darkness. Its cameras and patented software can track individuals by identifiers such as body metrics, hair color and clothing.