Research On The Key Technologies Of Network Dome Camara Based On P2P Principle

Network Dome Camera is a highly integrated device which is combined with mechanical, electronic, video information and computer network technologies. It is one of the most important service of network video surveillance system. Based on embedded system, Network Dome Camera can capture the raw video, encode video and transmit video stream over internet. Network Dome Camera based on P2P principle is an important extension and development of this field. Through the direct data connection, monitoring video stream can be transmitted real-time and remotely. This technology saves the network bandwidth and improves the network efficiency in effect.The thesis describes the general development history and the application field of Network Dome Camera, and specifies the shortcomings and developing direction of traditional Network Dome Camera. Then, the thesis gives the overview of the research status and applications of P2P network technologies. Also, the technological advantages of applying P2P principle to Network Dome Camera are pointed out. Based on the Network Dome Camera independently developed by our research group, the thesis makes in-depth research on several key technologies of Network Dome Camera based on P2P principle, including P2P principle and implementation, video stream transmission, video coding and rate control, etc.The thesis makes in-depth research on the key technologies, including network topology, instant messaging and the establishment of data connection. On the basis of research on features and topology architectures of various P2P network, A distributed surveillance system solution is proposed, which is based on hybrid decentralized architecture. The working principle and technology character of the solution is described. The thesis specifies the principle of this system and the application of XMPP instant messaging protocol in this system, specifically in the establishment of data connection. The peer application software has been programmed and debugged.The technology related to video stream transmission is discussed. The thesis uses RTP/RTCP protocols to transmit the video stream. Also, the thesis discusses the segmentation strategy for MPEG-4 video stream. PPPoE dialing protocol is introduced and implemented on the embedded system. The dialing module is implemented based on FSM software architecture and achieves good effect.Video coding and rate control are the key technologies of Network Dome Camera. The thesis does some theoretical and experiment research on the two fields. Coding scheme based on video object is applied for simple monitoring scene. A linear experience model of AMSE-QP is proposed. Based on this model, A single-pass VBR feedback control method is proposed for fix bandwidth network. Simulation experiments prove that this method is simple and effective. In addition, scalable video coding technologies for variable bandwidth network is discussed.Finally, A summary is given for the whole thesis, and some suggestion about research direction is proposed.