【作者】 吴浩；

【导师】 谢长生；

【作者基本信息】 华中科技大学 ， 计算机系统结构， 2007， 硕士

【摘要】 传统的家庭娱乐方式正发生着飞速的改变。随着数字家庭系统的流行,消费者越来越愿意坐在客厅里,通过大屏幕电视和高保真音响来欣赏网络媒体内容。数字媒体适配器(Digital Media Adaptor, DMA)是数字家庭系统的重要组成部分,它使传统的影音家电与网络媒体服务器能够方便地互连,不仅有较强的网络连接功能,还具备强大的音视频媒体解码输出能力,同时具有方便配置、方便使用的特点。数字媒体适配器系统由嵌入式硬件平台、底层平台软件、通用即插即用(Universal Plug and Play, UPnP)中间层软件以及上层应用构成。嵌入式硬件平台采用了Intel IXP425网络处理器和EM8620L媒体处理器的双芯片方案。为了给上层应用提供足够的存储支持,系统还配备了高容量、低成本的DOC(DiskOnChip)电子盘。底层平台软件包括板级支持包、Linux内核和根文件系统。与x86平台的通用性特点不同,嵌入式系统需要对底层平台软件量身定制,如内核的裁减、根文件系统的组织。针对DOC电子盘这种存储设备,研究并编写了相应的启动引导代码。UPnP协议栈提供了零配置的网络互连功能。UPnP AV规范的应用使得系统能方便地获取家庭网络内的媒体信息。在对UPnP AV协议充分分析的基础之上,对协议栈进行了适当精简,设计了适合数字媒体适配器的中间层模块,并借助Intel UPnP Development Toolkit开发工具实现了媒体服务器控制点(Media Server Control Point, MSCP),定义了相关调用接口,成功地应用在数字媒体适配器系统中。针对上层应用,采用了基于QT/Embedded的应用程序作为图形用户界面。应用程序整合了UPnP中间层软件和媒体播放组件,实现了对家庭网络内数字媒体文件的查询、浏览、整理和播放。更多还原

【Abstract】 The concept of Digital Home becomes more and more popular recently. Traditional fashion of home entertainment is changing. People are eager to enjoy a variety of media content from the local network or internet in their living rooms. The Digital Media Adaptor (DMA) is a key component in the Digital Home environment. Along with the powerful media decoding functions, the DMA has intelligent network interconnect capability which is easy to configure and simple to use.The design of DMA system is composed of embedded hardware, embedded platform software, the Universal Plug and Play (UPnP) middle ware and applications. The hardware platform mainly consists of the following components: an Intel IXP425 network processor, which is used for running the operating system and network stack, a Sigma Designs EM8620L media processor for multimedia decoding, and a DiskOnChip (DOC) NAND flash drive which offers adequate storage space for applications. The platform software are board support packages (BSP), the Linux kernel and root file system. Different from the general x86 platform, the platform software for embedded systems needs to be customized, including the porting of BSP, the kernel configuration and the organization of root file system. In order to support the DOC drive, a special boot code is also implemented.Universal Plug and Play micro stack offers zero configuration interconnectivity. Complied with UPnP AV specification, the DMA system can easily discover the information of media content on the home network. With the help of the skeleton module and function libraries provided by Intel UPnP Development Toolkit, a media server control point (MSCP) is implemented, after the detailed analysis and proper simplification of the UPnP AV protocol.As to the design of applications, the DMA system offers a user-friendly application program based on QT/Embedded GUI. The application is integrated with UPnP middle ware and Sigma Designs media libraries, and can be easily controlled by a remote controller. This system is successfully applied with the multifunction of inquiry, browsing, management and playback of various network multimedia.更多还原