Mpeg4-based Multimedia Digital Video Surveillance, Research And Design Of The Acquisition Subsystem

Because of it's specialty of immediacies convenience and exuberance,video surveillance becomes strong measure in security defense fields such as production management, traffic finance residence and community.Video surveillance technology has evolved quickly in recent years with the rapid development of communication technology, multimedia technology and network technology .Now it steps into digital surveillance state,and takes on a multiform trend.Based on the research of video surveillance system's history actuality and trend, thesis complete the research and design of gather subsystem of multimedia digital video surveillance.There are main modules such as video gather module local play module and network transmission module in this subsystem.Offer the realization of MPEG4-based video data compress arithmetic.MPEG4 is object-based,and is a dynamic standard.It becomes the first choice of data compress of video surveillance system because of it's merits such as saving storage taking less bandwidth, strong error resilience, better image quality, variable bandwidth and scalability,etc.At the same time.propose a FGSS-based compress scheme for video data according to the characteristic of living surveillance network. FGSS coding scheme can resolve the problem of the constant bit rate in traditional coding method, by which the bitstream can be cut down at any point. This scheme has better error-recovery ability and can adapt to the flexibility of network bandwidth,whick can achieve better effect of surveillance.Adopt DirectShow technology in design of local play module,which also is a innovation of thesis.According to construct theory of Filter,we finished the formation of Filter Graph module, the loading of media file, the link of output Pins,till the play of media files.Achieved the network transmission of video data by adopting Winsock programme method and multithreading mechanism.Winsock is not a networkprotocol,but a open network program interface supporting multi-protocol,which offers a communication port in computer.With the help of this port computer can communicate with every computer that has a Socket port.In the same way,the application of multithreading can make the progress of encode, transmission, decode happen together,and which advance the efficiency of image transmission.