【作者】 杨恩泽；

【导师】 高晓蓉；

【作者基本信息】 西南交通大学 ， 光学工程， 2007， 硕士

【摘要】 本文以“机车车辆轮对动态检测装置”为研究背景，以改进提升装置性能为目标，研究在Altera公司的FPGA(Field Programmable Gate Array)芯片Cyclone上实现图像采集控制、图像处理算法、JPEG(Joint Photographic Expert Group)压缩编码标准的基本系统。本文使用硬件描述语言Verilog，以RedLogic的RVDK开发板作为硬件平台，在开发工具QUARTUS2 6．0和MODELSIM_SE 6．1B环境中完成软核的设计与仿真验证。数据采集部分完成的功能是将由模拟摄像机拍摄到的图像信号进行数字化，然后从数据流中提取有效数据，加以适当裁剪，最后将奇偶场图像数据合并成帧，存储到存储器中。数字化及码流产生的功能由SAA7113芯片完成，由FPGA对SAA7113芯片初始化设置、控制，并对数字化后的数据进行操作。图像处理算法部分考虑到实时性与算法复杂度等因素，从装置的图像处理流程中有选择性地实现了直方图均衡化、中值滤波与边缘检测三种图像处理算法。压缩编码部分依据JPEG标准基本系统顺序编码模式，在FPGA上实现了DCT(Discrete Cosine Transform)变换、量化、Zig—Zag扫描、直流系数DPCM(Differential Pulse Code Modulation)编码、交流系数RLC(Run Length code)编码、霍夫曼编码等主要步骤，最后用实际的图像数据块对系统进行了验证。更多还原

【Abstract】 With the background of "the dramatic inspect equipment of vehicle wheels" and the aim of improving the performance of the equipment, this paper studies about the realization of image collection and control, image processing algorithm, and JPEG basic system on the chip Cyclone from the Altera company’s FPGA. With the hardware platform of the Redlogic’s RVDK, it completes the design and the simulative confirmation of the soft core with the hardware descriptive language Verilog in the environment of the exploited tool QUARTUS2 6.0 and MODELSIM_SE6.1B.The function of the image collection part is to convert the analog data from the analog camera into the digital data, and then to pick up the useful data from the data flow, and finally to incorporate the odd and even field into a frame and save it to a memory after the appropriate cut. The function produced by the digital data flow is completed by SAA7113 chip, however, FPGA chip initializes and controls the SAA7113 chip, and manipulates the digital data as well.Taking account of some factors such as real time character complexity of algorithm, the image processing algorithm part chose three algorithms to realize, they were histogram equalization, median filter and edge inspection.According to the order coding mode of the JPEG basic system, the compressed code part realized DCT transform, quantized, Zig—Zag scan, DPCM encoding of direct current coefficient, RLC encoding of alternating current coefficient, Huffman encoding. Finally, an actual image data was used to validate the whole system.更多还原