The Design And Implementation Of Handheld Wireless Video Monitoring Terminal

With rapid development of technology of computer, micro-electronics, multimedia and wireless communication, various digital multimedia video monitoring systems have arisen in market these days. Digital video monitoring system which has more advantages than traditional one, has taken the place of analog monitoring system step by step and been used widely. Meanwhile, the development of wireless network has brought about tremendous changes in many fields. The goal of this thesis is to design a handheld wireless video monitoring terminal, which integrates the mature technology of video monitoring with that of wireless network growing up gradually.In the second chapter the general design of handheld wireless monitoring terminal is introduced. The hardware platform of "Sitsang", porting of Linux OS and the desktop manager of "Qtopia" concerned in the design are also presented.In the third chapter of the thesis the protocol of 802.11 which is very popular now is described, and the emphasis is put on the relationship among the modules of PCMCIA, and the implementation of the driver of wireless network interface card based on Linux OS.In the fourth chapter of the paper how to manage many sockets in an application of single thread is discussed, a series of real-time stream protocols which are used widely, such as RTSP, RTP and RTCP are analyzed, and the design of these protocols with language of C++ is proposed.In the fifth chapter the issues designing and using library of ffmpeg are presented. Modules of queue for video packets, decoder for MPEG4 using multi thread technology, controller of pan and monitoring source selected are all designed.In the sixth chapter the tests of handheld video monitoring terminal in the experimental environment are given.Finally, the works done in the thesis are summarized , and the deficiencies and improvements are analyzed. The perspective is also given.