摘要汽车牌照自动识别系统（VLPR）作为智能交通系统（ITS）中的核心环节，是计算机视频图像识别技术在车牌自动识别领域中的一种应用。该系统综合了图像处理、模式识别以及人工智能等诸多领域的高新技术。其目的是从复杂的背景当中将运动的汽车牌照定位并提取出来，再通过图像采集、图像预处理、特征提取、车牌定位、车牌字符识别等技术识别车辆牌号。    车牌定位作为汽车自动识别系统（VLPR）中的关键环节和首要步骤，其定位的速度和准确度直接影响到整个系统的性能。 本文主要研究车牌定位技术，论文介绍了车牌定位技术的国内外发展概况，采用的各种定位算法及国内车牌的特点及数字图象处理基础知识。然后应用 matlab 编程，完成对车辆图像的灰度变换、直方图均衡图像增强、基于 sobel算子的图像边缘信息提取。最后应用形态学开运算和闭运算对边缘图像进行腐蚀和膨胀处理，得到矩形块。再通过分析矩形块的比例、水平垂直投影特性判断出正确的车牌区域，完成车牌定位。31121
毕业论文关键词  数字图像处理  车牌定位  Sobel 算子   Matlab
Title  Study of Car License Plate Location Based on Matlab
Abstract Vehicle license plate recognition system (VLPR), which is the hard core of modern Intelligent Transportation Systems (ITS), is one of the applications of computer video image recognition technology in vehicle license plate recognition, and is the synthesized technology of image processing, pattern recognition,  artificial intelligence, and many other fields’ technology. The system  that  requires vehicle license  to be located  from  the  complex background ,and further extracted ,identifies license plate by using those technology of  plate location, image acquisition, image preprocessing, feature extraction, license plate character recognition and so on. As Vehicle license plate recognition system (VLPR)’key and first step, the speed  and accuracy of license plate location directly affects the performance of the entire system. The study mainly aims at plate location technology, and the paper introduces the development situation of license plate location in domestic and foreign, various location algorithms, the characteristics of domestic plate and the basic knowledge of digital image processing. Then using matlab programming completes  vehicle image intensity transformation, histogram equalization image enhancement, image edge information extraction based on  sobel operator. Finally, The image is etched and expanded by morphological opening operation and closing operation of the edge in order to get a rectangular block. The correct license plate is ensured  by analyzing the ratio  feature  of rectangular blocks, horizontal and vertical projection characteristic. At last,  completing the license plate is located.
Keywords digital image processing  car license location  Sobel operator   Matlab
目次
 1  绪论  .  1
1.1    研究背景及现实意义 1
1.2  国内外车牌定位算法研究概述 .  2
1.3  车牌定位技术的前景及难点  .  3
1.3.1 车牌定位技术的发展前景  .  3
1.3.2 车牌定位技术的难点  .  3
1.4  中国汽车牌照的特殊性  .  5
1.5  论文的研究思路  .  7
1.6  论文内容安排  .  7
2  课题相关基本理论概述 .  9
2.1  数字图像处理的基本概念及运算 .  9
2.1.1 图像的数字化  .  9
2.1.2 数字图像处理    10
2.1.3 数字图像处理的基本运算    10
2.1.4 数字图像处理的基本内容    11 基于sobel算子Matlab的车牌定位算法研究:http://www.youerw.com/tongxin/lunwen_27170.html