MPEG4流媒体节目源编码系统的设计与实现

【作者】 樊振萍；

【导师】 唐继勇；

【作者基本信息】 电子科技大学 ， 模式识别与智能系统， 2005， 硕士

【摘要】 网络技术与多媒体技术的发展,促进了通信技术的综合化、数字化、智能化、个人化的发展,使得在单一网络平台上实现语音、数据、图象等多种业务成为可能。综合了网络技术与多媒体技术的网络多媒体点播与组播技术正是在这个背景下产生的,并得到了迅速的发展。MPEG-4 系统是当前流行的一种多媒体编码方式,广泛的应用于低码率传输,如何在网络上实时传输MPEG-4 码流是当前的一个研究热门,也是未来网络多媒体的一个重要的研究方向。结合上述背景,本文研究并总结了网络多媒体通信的基本原理和关键技术,详细介绍了实时网络传输协议RTP/RTCP 以及通过RTP/RTCP 传输MPEG-4 的技术。参照现有的标准及方案,构建了一个基于MPEG4 和RTP 的流媒体服务系统的节目源制作系统。本系统分别采用硬件压缩与软件压缩两种方案实现,其中硬件压缩采用了optibase 公司的MPEG4 MovieMaker 400 硬件压缩卡,软件压缩采用ViewCast 公司的Ospray 200 视频采集卡。本文系统地介绍了该系统的需求、整体设计方案,并详细说明了节目源制作各个模块的开发过程,包括采集模块、节目编码模块、媒体流化模块等。测试结果表明,本系统达到了MPEG-4 网络点播与组播的基本要求,能实时传输图像和声音,并在一定范围内达到音视频同步。本系统采用面向对象的分析、设计、实现技术和客户机/服务器结构(C/S)的数据库设计模式,系统使用组件开发技术,提高了代码的可重用性和系统的可维护性。项目开发过程中严格按照软件工程的要求对项目进行有效管理,采用UML 统一建模语言为系统建立软件生命周期中各阶段的模型,分别选用Visual C++、My SQL 作为系统编程和数据库开发工具。更多还原

【Abstract】 The development of network technology and multimedia technology has greatly improved the communication technology of integration, digitalization, intellectualization and personalization, which makes it possible to realize integrated services of audio, data, video, and so on, on a single network platform. Therefore, under such a background, the network multimedia Unicast and Multicast , which integrates network technology and multimedia technology, has appeared and made fast development. MPEG-4 is a very popular multimedia codec, which used in the low bit-rate transport in the network, how to transport MPEG-4bit-stream in the network real-time is a hotspot of research . According to the above, the basic principle and key technology of multimedia transport have been researched in the paper, and it introduces the real time transport protocol RTP/RTCP and how to transport MPEG-4 over RTP/RTCP. Refer to standard and project existed, a stream-media serving system’s program source execution system based on MPEG-4 and RTP/RTCP has been designed and implemented. This system adopt two project, they are hardware encode and software encode. Hardware encode adopt optibase company’MPEG-4 MovieMaker400 hardware compress card, Software encode adopt ViewCast company’Ospray 200 video capture card. This paper introduces the requirement & whole design project of this system, and then details research process of every program source produce module ,which including the capture module, encode module, decode module and streaming module. The test result shows that the system can transport MPEG-4 video and audio Unicast or Multicast and playback the video and audio sync. The oriented object analysis and design method and the develop technology of components is adopted in the development of the system, which can improve the reuse of the code and the maintenance of the system. The Unified Modeling Language (UML) is used to build the system’s model that perfectly aimed developer to correctly understand system’s function and aimed the communication of developer and user. Visual C++ is selected as program tool and MySQL which structure is client/server as the develop tool of database.更多还原