Video Conferencing System

Video conferencing is a new way of conference in the era of network. Before it came out, people wanted to meet by distance only using conference phone technology, and conventioneer could only listen to each other not see each other. As the videoconferencing coming, the effect of conference discussing is heightened greatly because of video.There are three types of videoconferencing system. One is large-scale one which applies in army and monopolies. This system is composed by MCU and works very well but it's very expensive. The latter is middle-scale one which applies in normal companies and enterprises. It is composed by light-scale MCU and simple software, but it's also expensive. The last one is videoconferencing system realizing by pure software, which applies in small-scale videoconferencing with low demands. This system is developed on software platform provided by large-scale software companies. It is an interactive multipoint videoconferencing system without MCU, namely multicasting. This paper researches modern videoconferencing technologies and corresponding criteria, detail analyses network flow media and Microsoft DirectShow, then designs a framework of videoconferencing system based on DirectShow. According to the design policy and the demands of project, first this paper formulates the requirement analysis, preliminary design, and then introduces how to build this system with DirectShow developed by Visual C++6.0 to realize these three functions: point to point meeting, multicasting meeting and data meeting. Finally, it formulates the details of technologies, research methods and realizing steps to build core function models. This paper aims to provide a solution for middle and small scale videoconferencing system, and realizes it.At the last, it advances some improved schemes and points out the research direction in the future.