The Design Of Embedded Video Surveillance System Based On CDMA

With the development of electronics, computer science, communication technology, embedded mobile video surveillance has become more and more popular. The video surveillance system which integrates with MPEG-4 video capture, codec and wireless transmission modules has been designed. The surveillance system uses a TMS320DM355 video processing chip based on DaVinci technology and MPEG-4 video codec format with a relatively low cost wireless module of CDMA2000 1X. Real-time surveillance video stream can be received with a fixed IP computer and client software through Internet.Based on many popular design solutions of embedded mobile video surveillance, a BCM-860L CDMA development board which connected with DM355 platform by an extended serial port has been designed. The platform uses the real-time MontaVista Linux operating system, taking full advantage of TI's XDM technology and IDMA3 interrupt resource description and negotiation protocol interface to design the video surveillance applications. Rendezvous module has been used in the application to synchronism with threads initialization and release, making more efficient use of memory resources. In order to stably transmit real-time video with high quality at a very low bandwidth, the compressed video stream is packaged and transmitted with JRTPLIB which based on RTP protocol, facilitating multicast surveillance with favorable conditions in the future. The author also study further with Core coding algorithm of MPEG-4 motion estimation, optimizing the most time-consuming MVFAST search strategy in motion estimation and improving the SAD matching operator. The improved video coding algorithm can effectively reduce the time-consuming of motion estimation without PSNR decline in video sequences. The improved algorithm can satisfy everyone in complex texture background.