Research On Key Techniques Of Multiplex Algorithm And Rtp Protocol Based On Avs In Cmmb System

As the development of mobile multimedia broadcasting technology and the intellectualization of the hand-held terminals, people put forward higher requirements to access to information anytime or anywhere. Throughing radio and television coverage net to provide mobile multimedia broadcasting services become one kind of practical and feasible technical solution.Our country proposed the system of CMMB in 2006, that is China Mobile Multimedia Broadcasting, which was based on independent intellectual property rights of our country. This paper mainly discussed the key techniques and realization of multiplex algorithm and RTP protocol based on AVS in CMMB system.Firstly, the paper introduced the real-time transport protocol and real-time transport control protocol, that is RTP and RTCP, focused discussed the audio and video streams'transmission from the AVS encoder to the CMMB multiplexer by the real-time transport protocol (RTP) and real-time transport control protocol (RTCP), which provided a network monitoring and quality feedback, providing a real-time network status for the encoder system. And eliminate the network jitter through the strategy of adaptive jitter buffer controlling.After RTP unpacked at the receiving end, restore audio and video frames by re-framing strategies, prepared for CMMB multiplexing on the next step.Secondly, the paper researched the multiplex theory of CMMB based on the reliable transmission of audio and video to the CMMB multiplexer, and has carried on the design of audio and video's synchronization before the audio and video were multiplexed by the CMMB multiplex, guaranteed the synchronization of audio and video playback in terminal, and carried on the encapsulation of the audio and video streaming in accordance with principles of CMMB multiplex. Packing the audio and video streams into audio segment and video segment respectively through service processing module, multiplexing the audio and video segment into the multiplexed sub-frames and then generate the multiplexed frame by multiplex module.This paper's significance is about the realization of real-time transmission system for audio and video streams based on AVS video coding from the AVS encoder to the CMMB multiplexer, and does an in-depth analysis of CMMB multiplex principles.