【作者】 张玉民；

【导师】 陈定方； 龚自康；

【作者基本信息】 武汉理工大学 ， 计算机软件与理论， 2008， 硕士

【摘要】 众所周知,人类通过视觉获取的信息量约占总信息量的70%,而且视频信息具有直观性、可信性等一系列优点。近年来,随着网络技术、多媒体技术、通信技术的快速发展,网络视频技术的应用日益增多,市场需求也越来越大。应用非常广泛,从日常生活、工业生产直到现代安防、科学研究等领域都已涉足。目前,视频监控开始突破传统的时空限制,向网络化,数字化方向发展。以计算机技术为基础,以网络为依托,以嵌入式设备为载体的视频监控可以使实时远距离传输成为可能。嵌入式技术是计算机技术的延伸,其出现使得计算机研究进入一个新的领域,成为当今的热门话题之一。本文在总结分析以往研究成果的基础上,将嵌入式技术、网络技术、视频技术有机的结合起来,提出了基于嵌入式平台的流媒体格式传输的网络视频监控系统的设计方案,其特点是性能稳定、维护管理方便、可扩展性强。与基于PC机的视频系统相比,其优点是成本低、功耗小、应用灵活、易扩展和升级。系统利用网络实现远程监控,摄像头采集到的数据经开发板传送到Web服务器,监控人员在客户端就可以浏览被监视端的情况。本文以嵌入式系统、视频采集和流媒体传输为背景,总结了现代嵌入式系统的特点、原理与开发方法,论述了系统开发环境的构建、系统的移植、视频采集程序和流媒体传输程序的设计与实现。本文采用基于ARM9核的三星s3c2410处理器的开发板和USB摄像头的硬件,软件采用Linux内核开发平台。在嵌入式开发环境构建中,介绍了Linux在宿主机的安装和设置,交叉编译器的制作;在系统移植方面介绍了Bootloader和Linux内核的移植、根文件系统的制作,在驱动程序的移植方面重点介绍了USB通信原理和如何利用现有驱动程序来编写相应设备的驱动程序,这是本文的一个创新点;视频采集方面利用相关库提出了多线程采集的思路,有助于加快采集速度;在流媒体方面重点介绍了利用现有库文件来编写流媒体格式传输方法,以提高工作效率;最后本文还介绍了程序的烧写与测试,这一步是嵌入式系统所特有的工作。应用程序设计采用了模块化设计的方法,减少模块的耦合性,提高了系统的效率。在所开发的视频监控系统中,文中讨论的研究技术已经获得成功,取得了良好的效果。后PC时代,嵌入式系统将拥有非常大的市场潜力,从事嵌入式系统开发的人员也越来越多。对嵌入式系统的研究与开发除了需要丰富的软硬件知识外,还需要有大量的实践经验,理论与实际相结合是研究嵌入式系统的有效手段,也是促进嵌入式系统快速发展的方法。展望未来,明天的嵌入式系统会比今天更便宜、小巧、可靠、高效及智能化,嵌入式系统的发展潜力巨大无比。更多还原

【Abstract】 It is well known that the information content obtained by vision occupies 70% in the total information content, and video frequency information has a series of advantages of visualization and reliability. In recent years, according to the fast development of network technology, multimedia technology, communication technology, the market need of network video frequency is widely used in many fields, such as daily life, industrial production, modern security, scientific research. Now, video frequency surveillance begin to break out traditional space-time limit, towards the development of network and digitalization. Real-time long-range transport become possible through video frequency surveillance based on computer technology, network technology, embedded equipment.The embedded technology is the spread of computer technology, that is to say, it makes computer technology entering into a new field. So it becomes one of the hottest topics. Based on the previous research results, this paper put forward design program of network video frequency surveillance system of streaming-media transport on the embedded platform, conbining with embedded technology、network technology、video frequency technology. It has the features of stable performance、easy maintenance and management、strong expansibility, and the advantages of low cost、low power、flexible use、strong expansion and upgrade, compared with video frequency system on PC computer. This system has realized remote supervision using network, the data collected by camera is transported to Web server through development board, so in this condition, the client can brows the monitor.This dissertation summarizes the features, theory and development method of modern embedded system, and discusses the construction of developing environment, system transplantation, design and implementation of video collection program and streaming-media transportation program, on the background of embedded system、video collection and streaming-media transportation. It adopts the development board of Samsung s3c2410 processor based on ARM9 board and the hardware of USB camera, and the software on the platform of Linux kernel. In the construction of embedded developing environment, the installation and setting of Linux on the host computer are introduced. In the system transplantation, transplantation of Bootloader and Linux kernel, the manufacture of Root File System are introduced. In the transplantation of driver program, USB communication theory and the driver program of the related device how to make by using the exist driver program are introduced emphatically, which is also an innovation. In the field of video collection, the multi-threaded collection thoughts are put forward by using the related library, help to accelerating collection speed. In the field of streaming media, the streaming-media transportation method made by using the exist library file is introduced emphatically so as to improve work efficiency. At last, program download and testing are introduced, which is the specific work in the embedded system. The application adopts module design method, to reduce the coupling, to improve the system efficiency. In the developed video frequency surveillance, the studied technology discussed achieves success and has a better effect.The embedded system will have the greater market potential and the more developers busy on it in post PC era. Apart from the abundance of software and hardware knowledge, it needs the large of practise experience.The integration of theory and practice are both an effective means of the researhing embedded system and the method of promoting the embedded system fast developing. Looking into the future, the embedded system will be cheaper, smaller, more realiable, more efficient and more intelligent than today.Embedded system will have a greater market.更多还原