A wireless video surveillance system with an active camera
This paper introduced a camera surveillance system in wireless communications. The system contains three major modules, PTU (pan-tilt unit) camera control for surveillance video capture, cross-layer control for data compression and transmission, and error concealment for video quality enhancement. Our contribution is twofold. First, a system design for data collection and transmission over wireless networks is presented and is evaluated with physical surveillance equipments. The camera is capable of following the moving target according to the control information. The end-to-end distortion estimation in the delay constrained video coding process takes into account the dynamic channel condition and physical layer modulation and coding scheme (MCS) to determine optimal coding and transmission parameters. Second, multiple error concealment strategies, including interleaving, boundary match and video up-sampling, are applied utilizing the special property of the PTU camera motion.