The Research Of Video Conferencing Based On Self-adaptive Transmission Control

Presently, the multimedia techniques became a very important part of information transmission.Video conferencing system becomes more and more important and value than before, as the means of new communication platform and information exchanging, more convenient, flexible and complete service and transmission can be offered by video conferencing system without limit of areas.This paper researches the self-adaptive video conferencing systems from studying the characteristics of it and the congestion of network. This paper studies deeply on self-adaptive control tactic about video conferencing and proposes an improved arithmetic of mechanism on receiver and sender, which includes two points.Firstly, it takes advantage of layered video coding, sets down a set of video transmission scheme according to different compressed ratio and established multi-layers transformed video scheme based on different bandwidth called Finite State Machine (CFSM) model.Secondly,it takes improved RTP/RTCP protocol on receiver to realize self-adaptive control of video data transmission.Then improved self-adaptive packed arithmetic about multimedia data reduced packet loss rate when network is congested.A video conferencing system based IP multicast is designed. This system takes Visual C++6.0 as platform, combining multicast techniques, WINSOCK techniques, DirectShow techniques .Finally, self-adaptive transmission models are realized. A simulation software is taken to evaluate the algorithm's performance. Results demonstrate that the control mechanism can tolerate occasional bandwidth changes in the presence of transient network congestion.Finally, the conclusions of mechanism and the future trends of study are given.