ISCAS Special Session Demo: Wireless Video Sensor for Ad-hoc Networks

An ultra low power, low bandwidth wireless video sensor network is presented. Each wireless node includes a 90 by 90 CMOS image sensor node with focal plane temporal intensity change detection. As output, the camera provides not only the image intensity, but a digital flag indicating the presence and direction of change, thereby resulting in significant reductions in the amount of external memory and processing power necessary required for operation. Several compression schemes have been developed that take advantage of the change difference signaling from a pixel update wake up mode to a full motion DCT macroblock based scheme. Under typical surveillance scenarios, the temporal change encoding provides up to a twenty fold compression. The sensors have been successfully integrated with a ad-hoc wireless networking system.