Network-Aware H.264/AVC Region-of-Interest Coding for a Multi-Camera Wireless Surveillance Network⋆

Surveillance video is characterized by short periods of activity in a small region of the image, and long periods of inactivity. When transmitting such video sequences over a wireless network, it is important to dynamically adapt the encoding of each stream according to both the video content and the underlying network conditions. We propose a video surveillance system that exploits H.264/AVC compliant region-of-interest (ROI) coding for more efficient representation of the captured video signal. Information exchange between the application and transport layers is used to guide dynamic selection of reference pictures for temporal prediction, as well as adaptation of encoding quantization parameter. Performance gains resulting from the various proposed schemes are confirmed in simulations of an 802.11 surveillance network comprising 7 cameras. Index Terms Video surveillance, H.264/AVC, crosslayer design, Region of Interest.