The Research And Implementation Of Video Coding Technology In Wireless Network

With the development of information society, multi-media technique has found extensive application areas. In the world of multi-media, video technique plays a key role, especially in the area of video surveillance, stream media and digital TV. The research on the technology of video communication becomes a focus in wireless network. The video image needs to be coded for the video real time communication in wireless system. In order to meet customers' increasing demands of the bandwidth of network and the quality of video, different organizations have enacted next generation video standards such as MPEG-4,EL264. The thesis mainly studies MPEG-4, and improves the parts of the key technology.At first, this thesis gives an overview of the method of MPEG-4, mainly studies video segment technology, and presents an algorithm of segmenting moving objects automatically in video sequences. The basic idea is to use the information of the difference of adjacent frames, introducing gradient filtering and background formation technology to initialize object, then to employ distance method to track object. Experiment results show that above-mentioned algorithm acquire good coding performance.Then, the thesis introduce the basic theory and key points of the core technology of MPEG-4 ,which is block-matching motion estimation, and proposes a new diamond search algorithm .To check out the new algorithm ,the paper has implements video code by code which involves motion estimation. The experiment results demonstrate that the new algorithm improve video code to some extent.Finally, the thesis applies MPEG-4 code to video server, uses the exiting equipment to construct the wireless LAN and simulates wireless communication environment, realizes the real time communication of video image between PC.