【作者】 杨小宇；

【导师】 杨斌；

【作者基本信息】 西南交通大学 ， 交通信息工程及控制， 2011， 硕士

【摘要】 随着“信息高速公路”的兴起和发展以及音视频压缩技术的进步,音视频点播系统开始进入新的领域,并且能为行业用户提供多种解决方案,以满足用户的各种需求。基于嵌入式手持设备的点播系统是继互联网音视频点播系统之后新兴的一种传媒方式,它是嵌入式技术、无线网络通信技术、多媒体技术等多学科、多领域融合交叉的产物。本文以音视频点播为研究对象,以基于Linux操作系统的嵌入式手持设备作为客户端设备,并通过与服务器端相结合实现一个完整的运行于无线局域网的点播系统。运行在手持终端上的客户端具有用户验证、浏览并播放视频等功能。服务器端以统一数据资源为核心,通过统一身份认证,将各应用系统中用户权限范围内的功能进行集中提供,用户可获得基于角色的个性化操作界面。客户端和服务器的通信基于无线WIFI网络,视频的压缩采用H.263或H.264视频压缩标准。本文针对构建一个适合于手持式设备的点播系统的三个主要部分分别提出了高效的解决方案。在音视频的数据传输上,为了充分利用无线网络的带宽,提高音视频传输速率,本文在详细分析了传输层TCP协议和UDP协议的原理的基础上,设计并初步实现了一种基于UDP协议之上的文件流传输协议：FSTP(File Stream Transport Protocol)协议。其次,在MAGUS手持设备上,充分利用其提供的ARM9和DSP双核优势,实现了一个高效的流媒体播放客户端。最后,为了使流媒体服务器能同时支持尽可能多的客户端,设计并实现了一种Linux下的结合了线程池和I/O复用的高性能服务器模型,并应用在流媒体服务器中。更多还原

【Abstract】 With the rapid development of "information superhighway" and the improvement of audio and video compression technology, VOD system has entered a new area, and can provide a variety of industry solutions to meet user needs. The VOD system based on embedded system is a new system of mass media after the internet VOD system and is a combination of multiple technologies which include embedded technology, wireless network communication technology and multimedia technology.In this thesis, based on handheld devices which ported the embedded Linux operating system,a complete VOD system running on wireless LAN is impletementd. This VOD system consists of some client applications running on handheld devices and a server application running on PC server. The client application has many features such as user authentication, browsing and playing video and etc. By unifying the server side data resource and account authentication and providing centralized system functions within the user rights, user can access to personalized role-based user interface. Client and server communicates with each other based on wireless WIFI networks, video compression uses H.263 or H.264 video compression and coding standard.In this paper, effective solutions for three main components of the VOD system were put forward respectively.In order to take full advantage of the wireless network bandwidth and improve the audio and video transmission rate, on the basis of analyzing the TCP protocol and UDP protocol’s principle, FSTP (File Stream Transport Protocol) protocol which is a streaming media file transfer protocol on top of UDP is designed and implemented. Secondly, a high performance streaming media player which can fully utilize MAGUS plantform’s dual-core of ARM and DSP’s performance is implemented. Finally, in order to support multi-clients simultaneously, a new high-performance network servers model combining the thread pool and I/O multiplexing techonology is implemented and applied in streaming media server.更多还原