【作者】 杨磊；

【导师】 方康玲；

【作者基本信息】 武汉科技大学 ， 控制理论与控制工程， 2008， 硕士

【摘要】 图像视频采集技术在工农业生产、军事、医学、消费电子以及安全监控等领域有着极广泛的应用。传统的图像视频采集系统是由CCD摄像头,采集卡和计算机组成,一般功能较为齐全,但体积较大,价格高。随着嵌入式设备的出现和发展,该系统朝着微型化、网络化和智能化的方向发展。嵌入式图像视频采集系统一般是由微型摄像头、图像处理与微处理器芯片和存储器等构成的专用电路系统,具有体积小,功能强,接口丰富等特点,并且方便携带,与传统的大型图像采集器相比,嵌入式图像采集系统因体积小,便于移动,可以用于复杂环境下的图像采集。本文提出了一种基于ARM处理器的嵌入式图像视频采集传输系统的解决方案。该方案使用三星系列嵌入式处理器S3C2410 (ARM920T)为CPU,USB摄像头和LCD;系统软件平台使用嵌入式Linux2.6.14操作系统。与传统的采用Windows操作系统在PC上运行采集程序的方案相比,本系统体积小,便于携带,并且占用内存低。在软件算法上,与现有的单帧采集相比,本系统通过mmap函数将LCD显示缓冲区映射到用户空间的内存区,而直接对内存区进行读写来提高显示速度,并且在采集的时候使用了双缓冲设计,可以达到采集图像的同时显示在LCD上,故系统具有处理响应速度快,体积小,功耗低等优点。为了能适应网络的传输,本文的最后对嵌入式小波零树压缩(EZW)进行了改进,实验结果表明,在相同的压缩比下,改进算法要比EZW算法效果好。系统采用模块化设计,各部分相互协调、形成了一个完整的图像视频采集系统,并且有很强的可扩展性。由于使用ARM处理器,平台功耗较低,并且采用开源的Linux操作系统,并未使用商用的软件包,完全从底层开发,使整个平台软件部分开发成本较低,具有广阔的推广前景。更多还原

【Abstract】 Video images collecting in the industrial and agricultural production, military, medical, consumer electronics and safety monitoring, and other fields has a very wide range of applications. The traditional image collecting system is collected by the CCD camera, collecting cards and computer components, the general function is more complete, but the larger, higher prices. With the emergence of embedded devices and development in the miniaturization of the system, network and intelligent direction. Embedded image collecting system is composed of the miniature camera, image processing and memory chips and microprocessors, such as a dedicated circuit system, a small, functional strong, rich interface features, and portable, and compared to the traditional image acquisition, embedded image acquisition system is small, portable, and can be used for complex environment of image acquisition.This paper introduces a method of embedded collecting system based on ARM processor, The programme series of embedded processors using the Samsung S3C2410 (ARM920T) for the CPU, USB camera and LCD; System software platform is embedded Linux2.6.14 operating system. With the traditional use of the Windows operating system on a PC running the programme, the system has smaller size and portability, and low memory. The software algorithms compared to the acquisition of existing algorithms .it is through the mmap function and LCD display buffer will be mapped to the user memory space, and directly to the memory areas to improve the literacy rate shows, and in the acquisition of the Two-time use of the buffer design, image collecting can be achieved at the real time displayed on the LCD, the system has dealt with so fast response, small size, low power consumption advantages. It is able to adapt to the network transmission.and it the last of this paper,it impoves the EZW algorithm the experimental results show that in the same compression ratio, this algorithm is better than EZW algorithm.System is moduled in design. and become a complete video image collecting system.and has a strong scalability. As the use of ARM processors, it is low consumption platform. this scheme adopts open source linux system.and doesn’t use commercial software package,and develops form bottom completely,so the development cost of whole platform’s software is low,and it has wide market foreground.更多还原