Design And Implementation Of Video Surveillance System For Disaster Relief Based On Wifi

With the continuous development of computer network technology,the application of real-time video technology is more and more wide. In view of the current disaster relief is mainly carried out through the rescue workers directly entering into the disaster relief scene, how to apply real-time video technology to the disaster relief is an important research direction.Firstly, this thesis studies the key technologies of wireless video transmission system to select H.264 as the standard of video coding and decoding, use Wi-Fi as wireless transmission channel and determine UDP protocol combined with RTP protocol as the transmission scheme.Secondly, through the analysis of the demands of wireless video transmission communication system, we complete the selection of main components and build the hardware platform of the wireless video transmission system. Thirdly, according to the demands of the system,this thesis adopts the idea of modularization to design the software system, and realize modules of the video sending end and the video receiving ending with the open source project FFmpeg.Considering high packet loss of wireless channel and unstable environment of disaster relief scene, this thesis proposes a scheme of network packet loss recovery, which consists of two parts: forward error correction module and QoS module. The forward error correction module uses the optimized RS algorithm to construct the RS code, and solve the problem that the traditional RS algorithm may appear singular matrix during the process of constructing the RS code. The QoS module is mainly used to the problems of disordered packets and repetitive packets in video receiving end.Lastly, the system software developed in this thesis is tested and simulation of the scheme of network packet loss recovery is carried out under Matlab software, which proves the reliability of the system and the feasibility of the scheme of network packet loss recovery.