摘要
视频会议作为信息时代一种崭新的多媒体通讯方式，以其经济、快捷、不受地域限制等特性，日益受到众多企业用户的欢迎，于是视频会议技术也就成为了目前的一个研究热点。当前，视频会议标准协议主要是ITU-T发布的H．320和H．323框架协议，这两种协议曾经为视频会议领域的标准化作出了巨大的贡献，推动了视频会议技术的发展。
然而，基于H．320和H．323的传统视频会议系统由于受到协议机制的影响，限制了视频会议的规模，很难实现大规模的会议内容分发，不能满足大量用户实时收看视频会议内容的需求。
流媒体技术是最近几年新兴的一种网络媒体技术，是在Internet和Intranet中采用媒体数据流式传输的新技术，通常采用RTP、RTCP、RTSP协议作为传输和控制协议，支持实时广播和点播。
为了能让更多的授权用户能够实时收看到视频会议的内容，本文设计和实现了一种流媒体技术与视频会议相结合实现视频会议内容大规模分发的解决方案，这种方案利用流媒体技术良好的可访问性、可扩展性和对带宽的有效利用性，以及组播和单播相结合的分发方式，实现了视频会议内容的大规模实时直播，满足大量用户实时收看会议内容的需求。这种方案能在很大程度上扩展会议的规模。
本文中还引入了数字版权管理(DRM)、身份验证和用户授权等技术和机制，保证了直播内容的安全，实现了对用户的管理，为本方案的商业化打下了良好的基础。
本文中设计的流媒体技术与视频会议相结合实现视频会议内容大规模分发的方案能有效地扩展会议的规模，满足大量用户实时收看视频会议内容的需求，从而将进一步扩大了视频会议的应用领域。
As a brand-new multimedia communication means, videoconference is popular with many enterprise customers gradually because of its economy, convenience and distance-free, which becomes a hot issue recently. Standard protocols for videoconference mainly are H.320 and H.323 framework protocols published by ITU-T, these two protocols contributed to the standardization of videoconference and the development of videoconference technology.
Meanwhile, traditional videoconference based on H.320 and H.323 protocols limit the scale of the meetings greatly with the influence of protocol mechanism, which couldn't implement the content distribution in large scale, and then couldn't meet the needs of watching the videoconference in large scale.
Streaming Media is a kind of new technique for network media. It is a kind of media transmitted by stream on Internet or Intranet, which usually adopts protocols like RTP, RTCP and RTSP as real-time Video/Audio synchronization and flow control to implement data flow control, real-time broadcasting and watching on demand.
In order to help more authorized users watch videoconference in real-time, the thesis presents a new method of combination with Streaming Media and videoconference to implement meeting content distribution in large scale. This method utilizes the good accessibility, and expansibility of stream media, the high efficiency of bandwidth, and the combination between multicast and unicast to implement Live broadcast of videoconference in real-time. The method can meets the needs of watching the meeting content in large scale. It can expand the scale of videoconference greatly.
The thesis imports the technology and mechanism like digital rights management, identity verification and customer authorization to guarantee the security of content of meeting and implement the management to customers.
The combination of streaming media and videoconference proposed by the thesis implements the distribution of meeting content in large scale to enlarge the scale of meeting, and can meet the needs of watching real-time videoconference in large scale to expand the application scope of videoconference.
引文
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