【作者】 张小刚；

【导师】 丁振国； 任志纯；

【作者基本信息】 西安电子科技大学 ， 情报学， 2005， 硕士

【摘要】 在网上开展远程教育突破时空限制,为广大学习者提供极大的方便。网络视频教学是远程教育的一个重要组成部分,它主要实现师生在网络上的视音频交流。本文基于流媒体技术设计了一个视频交互的远程教学系统,对涉及的基本技术做了深入的探讨,并进行了软件实现。本文首先阐述流媒体技术的工作原理,重点讨论视音频数据的同步问题,提出一套同步方法,证明该方法有较好的效果。综述MPEG-4 标准的系统结构和MPEG-4 视频编码技术。分析TCP/IP 协议对实时传输的局限性,对RTP/RTCP 协议、MPEG-4 码流在RTP 中的包结构、反馈控制算法进行了深入研究,并对拥塞反馈控制算法进行了改进。最后,采用DirectShow 技术,给出了远程教学系统方案,对视频的实时采集、编码、传输和回放进行了编码实现。本文对视频传输在其他行业的应用也有较大的借鉴意义。更多还原

【Abstract】 Teaching in the Internet breaks though the limitation of the space-time and brings great convenience to the learners. The network video education plays an important role in the distance education. It realizes the communication of the video/audio on the network between teachers and students. To design and develop distance teaching system based on streaming media is discussed in this thesis. The relative technology have been researched and the system has been realized with software. This thesis introduces the principle of streaming media transportation. How to synchronize the video and audio data is emphasized, several methods are introduced to solve this problem, which have a good effect. It summarizes system architecture of MPEG-4, as well as encoding technology. This thesis discusses the limit of the TCP, RTP/RTCP protocol and RTP payload format for MPEG-4 visual streams, it has comprehensive research about feedback control algorithm and improves it. Finally, a feasible project of distance teaching system is designed. It depends on DirectShow technology. The components, such as the real-time sample, video encoding, video decoding and display, are programmed and tested. This article is a good reference literature for the video transportation application in other fields.更多还原