【作者】 魏晋啸；

【导师】 吴庆洪；

【作者基本信息】 辽宁科技大学 ， 控制理论与控制工程， 2008， 硕士

【摘要】 嵌入式系统是以应用为中心,以计算机为基础,并且软硬件可裁剪,适用于应用系统对功能、可靠性、成本、体积、功耗有严格要求的专用计算机系统。嵌入式系统一般由嵌入式微处理器、外围硬件设备、嵌入式操作系统以及用户的应用程序4部分组成,用于实现对其它设备的控制、监视或管理等功能。其广泛应用于控制领域、消费电子产品等行业,已成为现代电子领域的重要研究方向之一。而随着电子技术,多媒体技术及网络技术快速发展,视频监控系统也正在向嵌入式,数字化,网络化方向发展。嵌入式视频监控系统充分利用大规模集成电路和网络的科技成果,实现体积小巧,性能稳定,通讯便利的监控产品。本项的目的正是建立一个完整的基于ARM9核心处理器和嵌入式Linux操作系统的嵌入式视频监控系统。本项目是在ARM微处理器平台上,移植嵌入式Linux操作系统,并完成视频采集、压缩、传输任务。系统采用ARM微处理器AT91RM9200作为主处理器,以视频采集芯片ADV7181作为视频采集设备,用H.263视频压缩协议对视频数据进行压缩,最后通过中兴通信公司MG815+CDMA通信模块传输到服务器上。本论文主要分成五个章节:第一章首先介绍ARM和嵌入式Linux操作系统的特点和当前的发展概况,然后说明了本文的课题背景及意义;第二章描述了硬件开发平台。本系统采用了ALTMEL的AT91RM9200为核心的开发平台,并扩展了以视频采集模块和CDMA无线传输模块;第三章描述了本系统的软件开发平台,包括嵌入式Linux开发流程以及移植到具体硬件平台需要完成的工作,如U-Boot的移植、Linux内核的编译与裁剪、文件系统韵制作等;第四章首先论述了本系统中的难点FIFO设备的驱动编写,随后在对H.263视频压缩编码叙述的基础上针对块匹配运动估计给出了一种改进的菱形搜索算法代替原有的三步搜索法,并且通过实验结果证明,经算法改进优化的新菱形算法优于原先的三步搜索法;最后在第五章得出了实验结果,完成了视频数据的无线网络传输。更多还原

【Abstract】 Embedded system is a special computer system which suit the application with the strict request for the function,the reliability,the cost,the volume,the power loss,which is with the application as center,the computer as the foundation,and hardware and software cutting out.It is generally composed of the embedded micro controller,the periphery hardware devices,embedded operating system,and user’s application 4 parts,which is used to control, supervise or manage other devices.It has been used in the fields of control, consumer electronic product and etc,and one of the most important research aspect of the electron field.With the rapid development of the electronic technology,multimedia technology and network technology,video surveillance system is going to the embedded,digital,networked direction. Taking full advantage of LSI and networks of scientific and technological achievements,the embedded video surveillance system achieves volume delicate,performance stability,facilitate the surveillance of communications products.The project is in arm microprocessor platform,and porting embedded Linux system in it.It completes video capturing,compression,and transmission tasks.System uses ARM9(AT91RM9200)as the main processor, chip ADV7181 as video capturing device also uses software to compress the video data with H.263 and transmits the coded data to the server throughout the CDMA transmitting module which produced by ZhongXing Communication Company.This paper is divided into five chapters:chapter one summarizes the characters of arm and embedded linux,and then introduces the project’s background and signification;in chapter two,it gives a detail description for the construction of the platform.System uses an embedded platform centered with AT91RM9200 microprocessor,and then extends video capturing module and CDMA wireless transmitting module;Chapter three described the process of developing linux and work needed to do porting linux to a special platform, including porting U-Boot,compiling and trimming linux kernel,making filesystem;Chapter four described design of linux drivers in detail which is full of difficulties,and then.specifies standard,of H.263 video signal encoder. Estimation.A new diamond search algorithm for fast-matching motion estimation is proposed to replace the traditional three-step search algorithm in the motion estimation region.Experiments results demonstrated that the application on the new diamond search algorithm has improved the efficiency of compression ratio and computing speed in contrast to the three-step search algorithm.Chapter five is the system test.Finally the project presents the video data wireless trasmiting.更多还原