桌面视频会议系统中视音频实时交互的设计与实现

【作者】 刘军；

【导师】 刘毅； 李慧荣；

【作者基本信息】 山东大学 ， 计算机技术， 2006， 硕士

【摘要】 近年来，随着计算机网络技术、多媒体技术和通信技术的迅猛发展，基于IP的桌面视频会议系统的开发与应用已经逐渐成为当前计算机应用的热点之一。视频会议系统是指两个或多个不同地方的个人或群体，利用通讯网络和多媒体设备，将声音、影像以及文件资料等综合信息相互传输，达到实时的交互，以完成会议目的的通讯系统。 本文简要介绍了视频会议系统的发展过程，并对其发展趋势进行了展望。着重介绍了视频会议系统的结构和视频会议系统的关键技术，以及多媒体通信的需求。深入分析了基于局域网的多媒体通信标准H．323v2和多媒体通信的相关协议，在深入掌握H．323v2标准、相关通信协议和通信机制的基础上，提出了桌面视频会议系统的总体设计思路和视音频编解码方案，并给出了扩展的UDP和基于反馈的QoS保障等多媒体通信方案。最后利用DirectShow和WinSock技术实现了桌面视频会议系统中的视音频交互。通过分析视音频传输的性能，该系统具备了一定的实用价值，其各项技术参数完全可以满足局域网下的视音频实时交互要求。 通过对该课题的研究，我们掌握了桌面视频会议系统的关键技术，开发了一套经济高效的桌面视频会议系统，提高了设计多媒体通信系统的能力，为今后的工作打下了良好基础。更多还原

【Abstract】 In recent years, with the rapid development of network technology, multimedia technology and communicating technology, the developing and applying of IP-based multimedia conferencing system becomes one of the hot spots of the present computer applications. The multimedia conferencing system is a system that individual and group in two or numerous different place be capable to use communicate network and multimedia devices to transmission the composite information, such as audio, video, file, and achieve the Real-time interacting for the conference.At first, this paper briefly introduces the developing process of the video conferencing system; emphasizes the structure and the key technique of video conferencing system and the requirements of the multimedia communication, then analyses the LAN-based multimedia communication standard H.323v2 and the protocols of the multimedia communication. On the base of deeply mastering H.323v2 standard, correlative communication protocols and communication mechanism, we present a blue print of the desktop video conferencing system and the scheme of compress and code the video and audio, and bring up the expanded UDP and the QoS based on the feedback. At last, we implement the video and audio interacting of the system using DirectShow and WinSock. According to the Analysis of the performance of the video and audio transport, the system has some practicality value, the technological parameter could satisfied the requirements of the real-time interaction of video and audio in the LAN.By the research of this task, we grasp the pivotal technology of the multimedia conferencing system, exploit an economical and efficient system, improve the capability of designing the multimedia communication system, ground a good base for the farther work.更多还原