The SIP Video Communication Terminal Based On Multimedia Processor

With the development of technology in the network and multimedia area, the business of multimedia communication, especially the Video communication technology, has become a leading element in Internet applications. Video communication is continuous and dynamic image communication, with the character of more information, more transfer bandwidth and high require for network. The service of Video communication will be the main service of future wire/wireless network.Most Video communication systems are based on SIP or H.323 call control protocols. The Session Initiation Protocol(SIP) advanced by IETF has its distinct advantages: it is very concise in the structure, easy to be extended and more suitable to access the Internet. It can control the media gate way and thus control the terminal call streaming in a multi-domain network effectively. Under the circumstance that Softswitch is to become the next generation technology of network switch, SIP is considered as the kernel protocol in access layer of the Soft switch technology, and it has been successfully applied to several representative communication systems due to the interest of lots of famous telecommunication companies. Video communication systems have two ways of implement, one is hardware video communication system, it has special audio/video equipments and good vision, is easy to use, and has QoS guarantee; the other is software video communication system based PC, it is convenience for installment, expansion and update, also it is cheap,but it is not dedicated in audio/video data processing so that the software system based on PC is not effective. Digital media processor is one of DSP for audio/video, The hardware structure of DSP pr-ocessor core is especially designed for multimedia data processing,also plentiful multimedia data processing instructions are available.Because of powerful function and multiple periphery interface of digital media processor TMS320DM642,it takes only little periphery apparatus to make one complete single chip multimedia embedded system,so it is very suitabl for development video communication terminals.From this point, we have carried out some research work in the construction of embedded SIP video communication system based on media processor .This paper emphasizes on the implementation of embedded SIP video communication terminal based on media processor, including the realization of SIP stack, the capture and compression of video and audio steams, UDP transmission of stream data, This paper also introduces the structure of standard Video Communication, demonstrates the importance of SIP in the Softswitch network and makes comparison between SIP and the H.323 standard. In the first chapter the history/framework of Video Communication and media processor is introduced, and then the author's research work is also introduced. In the second chapter the author firstly introduces the structure of SIP, then demonstrates the implement of SIP stack on media processor. In the third chapter, the author discusses the realization of SIP terminal in detail, including the implementation of all modules. The forth chapter is about some conclusions and tasks in the future.