Design Of Multi-protocol Remote Video Surveillance And Implementation Based On Qt

With the rapid development of technology and economic,society pays more and more attention to security issues.As an important part of the security industry,the development of video surveillance systems is also very rapid.This development in monitoring equipment is its diversification:with surveillance cameras for fixed scenes and mobile individual equipment for flexible and varied scenarios.However,device diversity has made it challenging to simultaneously access devices using different protocols on a video surveillance system.In addition,due to the special use scenario,the mobile individual equipment generally uses 4G network or WIFI.When the wireless network is unstable,there will be a phenomenon such as a stuck and black screen on the video monitoring client.In view of the above problems,this dissertation designs a multiprotocol video surveillance system to simultaneously access the individual equipment based on the private SIP protocol and the camera based on GB/T 28181 standard,and studys how to improve the video quality as much as possible in the case of poor network environment,and implements the video surveillance client with the Qt framework.The main work and results are as follows:(1)Researched on the current status of video surveillance systems and monitoring quality optimization.Summarized the experience in the literatures,studied and introduced the SIP signaling protocol,GB/T 28181 standard,video codec and other technologies needed for system development.(2)Analyzed the communication protocol of the two devices that need to be accessed in the video surveillance system: the private SIP protocol of the individual equipment and the GB/T 28181 standard of the camera.Developed a set of SIP protocol which suits this two equipments and enables the landing of two devices based on different protocols in the same video surveillance system.(3)Analyzed the requirements of video surveillance system.Designed and implemented user management,device management,rights management,device login,video playback,PTZ control and TV wall module based on Qt framework.(4)Two different decoding processes are designed in the Qt framework for different video transmission formats of the two devices accessed.The individual equipment uses JRTPLib to receive RTP video stream,framing module recombination video frame,FFmpeg decoding and SDL display video;the camera device uses LIBVLC to receive and decode the PS video stream.(5)A video playback adaptive strategy is designed for the network instability that may occur in individual equipment.Combining parameters such as monitoring client buffer length,packet loss rate,playback frame rate and video playback rate,calculate a value for judging the current monitoring video quality,and use this value to determine the current monitoring video playback quality to make an adaptive change.(6)For each of the functions provided above,each function was tested to verify the feasibility of the solution.