车牌识别系统毕业设计.doc

车牌识别系统毕业设计篇一：车牌识别系统毕业论文 车牌识别系统毕业论文 论文题目 院系名称 专业（班级） 车牌识别系统车辆牌照定位 系统的设计与实现 计算机科学与技术系 计算机科学与技术 摘 要 车牌识别系统作为智能交通系统的一个重要组成部分，在交通监控中占有很重要的地位。车牌识别系统可分为图像预处理、车牌定位、字符识别3个部分，其中车牌定位作为获得车辆牌照图像的重要步骤，是后续的字符识别部分能否正确识别车牌字符的关键环节。车牌定位系统实现对车辆牌照进行定位的功能,即从包含整个车辆的图像中找到车牌区域的位置，并对该车牌区域进行定位显示，将定位信息提供给字符识别部分。在本文中作者分析出车辆牌照具有如下特征：（1）具有固定的长宽比；（2）车牌区域内部字符数目固定；（3）字符与背景之间存在很大的颜色差别；（4）对于含有车牌信息的灰度图像，其车牌区域边缘明显，灰度跳变大，相对于车牌以外区域，具有明显的特征等。所以，一般基于图像处理的车牌定位系统是通过分析车辆牌照的某些特征来进行定位的。针对车牌本身固有的特征，本文首先介绍了在车牌定位过程中常用的几种数字图像处理技术：图像的二值化处理、边缘检测和图像增强等。其次介绍了现在常用的车牌定位方法，并对这些方法进行分析，总结出各种方法的优缺点，然后在此基础上提出采用带边缘检测的灰度图像行扫描投影方法对车牌进行定位，并使用VC+6.0编码实现车牌定位系统。最后对该系统进行了测试，测试结果表明该系统具有良好的人机交互方式，具有较高的识别正确率和较快的识别速度，对用户给定的待测图像能够迅速准确地进行车辆牌照的定位并将定位结果显示给用户，该系统具有一定的实用价值。关键词：车牌定位，灰度图像，行扫描，投影AbstractAs an important part of the Intelligent Transportation Systems, License Plate Recognition System plays an important role in traffic monitoring area. License plate recognition system can be divided into three parts, i.e., image pre-processing, license plate location and character recognition. The vehicle license plate location is an important procedure which is used to obtain a license image. It is also the key of the following character recognition system which can identify the correct license plate characters. License plate location system can perform the vehicle license location function, i.e., finding the location of the vehicle license in the image containing the entire vehicle license plate, positioning the plate region and then demonstrating the location information on the xxputer screen which will be transferred to the character recognition system.In this thesis, the author analyzes the vehicle license and finds that it has the following characteristics: Fixed aspect ratio. Fixed license plate characters number. Great color difference between characters and background. Obvious edge and great intensity change for grayscale images with registration information, and obvious characteristics xxpared with the outer plate region. Therefore, the majority of image-based positioning systems perform location function by analyzing some characteristics of the vehicle license.According to the own inherent characteristics of license plate, this thesis introduces many xxmonly used digital image processing techniques in the location process of license plate: binary image processing, edge detection and image enhancement, and so on. Then, we introduce the xxmonly used methods of license plate location. Further, we analysis these methods and summarize their advantages and disadvantages. Moreover, we propose locating plate by using the gray-scale image projection and line scanning method with edge detection. This system was implemented by using the VC+ 6.0. Finally, the experimental results indicate that the system has a good human-xxputer interaction, a better identification rate and higher speed. For images provided by users, the system can quickly and accurately locate the vehicle license and display the location results to the users. Therefore, this system has some practical values.Key words: license plate location, gray-scale images, line scan, projection目 录摘 要 . I Abstract . III 目 录 . IV第一章 绪论 . 11.1 课题的及意义 . 11.2 课题主要研究的问题 . 11.3 系统设计的目标及基本思路 . 11.3.1 设计目标 . 21.3.2 基本思路 . 2第二章 车牌定位中常用的数字图像处理技术 . 32.1 汽车牌照的特征 . 32.2 数字图像处理技术概述 . 32.3 DIB图像概述 . 32.4 车牌定位中常用的数字图像处理技术概述 . 42.4.1 图像二值化 . 42.4.2 边缘检测 . 42.4.3 图像增强 . 5第三章 车牌定位方法研究 . 63.1 车牌定位常用方法介绍 . 63.1.1 基于纹理特征分析的定位方法 . 63.1.2 基于数学形态学的定位方法 . 63.1.3 基于边缘检测的定位方法 . 63.1.4 基于小波分析的定位方法 . 63.1.5 基于图像彩色信息的定位方法 . 63.2 基于行扫描灰度跳变分析的车牌定位方法 . 7第四章 车牌定位系统的设计与实现 . 84.1 车牌定位系统系统分析 . 84.1.1系统业务需求 . 84.1.2系统用户需求 . 84.1.3系统功能需求 . 84.1.4 系统运行环境需求 . 84.2 车牌定位系统的整体架构设计 . 84.2.1 系统总体架构 . 84.2.2 系统技术架构 . 94.3 车牌定位系统的功能模块划分和实现 . 104.3.1 系统的功能模块划分 . 104.3.2 系统的功能模块实现 . 11第五章 车牌定位系统的系统测试 . 165.1 系统测试过程 . 165.2 系统测试结果 . 175.3 测试结果分析 . 24第六章 技术要点回顾 . 266.1 难度分析 . 266.2 主要工作 . 266.3 应用的主要技术手段 . 266.4 存在的问题及展望 . 27结 论 . 28参考文献 . 29致 谢 . 30篇二：在车牌自动识别系统中对字符的分割与识别的研摘要随着世界各国汽车数量的急剧增加，城市交通状况口益受到人们的重视。如何有效 地进行交通管理，越来越成为各国政府和有关部门所关注的焦点。车辆牌照的自动识别 是计算机视觉与模式识别技术在智能交通领域应用的重要研究课题之一，是实现交通管 理智能化的重要环节。本课题是汽车牌照自动识别系统的一部分，建立了一个完全由软件来实现的汽车牌 照字符识别系统。本系统将输入的车牌彩色图像通过识别处理，输出可xx的字符串。 整个处理过程分为图像预处理、牌照的倾斜校正、字符分割和字符识别四部分。 图像预处理阶段主要是研究图像的灰度化处理、去噪处理以及图像的二值化操作。 针对由十光照等原因造成的图像黑白不分明，本文采用了改进的二值化算法，在OSTU 算法的基础上，改进了图像的处理效果。倾斜矫正阶段主要是先检测那些由十拍摄角度 等问题造成的车牌图像的倾斜角度，然后采用两次变换的方法对图像进行矫正处理。在 字符分割阶段，本文主要采用先分割后验证的方式保证分割的成功率，然后将分割好的 字符图像做归一化处理，统一大小。最后的字符识别部分首先利用数学形态学中的细化 处理，抽取字符的骨架，然后利用模板匹配法识别字符。本文研究证明:改进后的二值化算法可以较好的保留图像细节，消除噪音，抗噪能 力强;基十Hough变换求取倾斜角度，再采用两次变换的方法使得矫正后的图像失真较 小;通过细化处理后，再采用模板匹配法可以快速准确地识别出车牌字符等。 关键词:汽车牌照自动识别系统，二值化，细化，模板匹配法The Study of Segmentation and Recognition in theVehicle License Plate Automatic SystemxiaochunshuangABSTRACTWith the increment of vehicle all over the world, the situation of city traffic is attracted the recognition of people. How to manage the traffic effectively is bexxe the focus of people more and more. License Plate Recognition System is the xxputer vision and one of the important subjects for research that recognition technology employ in the field of intellectual traffic system, realize the intelligent important links of traffic administration.This topic is a part of License Plate Recognition System, has established one xxpletely the license plate character recognition system which realizes by the software. This system will input the car license color image through recognition processing, the string of character which the output might edit. The entire treating processes divide into the image pretreatment, the license plate correction for grade, the character division and the character recognition four parts.The image pretreatment stage mainly studies the image gradation processing, denoising processing and the image binaryzation operation. In view of because reasons and so on illumination creates the image black and white is not distinct, this paper has used the improvement binaryzation algorithm, in the OSTU algorithm foundation, improved the image processing effect. The inclined correction stage mainly examines that tilt angle of car license image because of shooting angle and so on questions, first，then uses the method which two times transform to the image to carry on correction processing. In the character division stage, this paper mainly uses the way guarantee division success ratio which divides first and second confirms, then will divide the character image will make normalized processing,unified size.The final character recognition part first uses in mathematics morphology refinement extraction the character skeleton, then use template match method recognitionThis paper proved that, the improvement binaryzation algorithm can retain the good retention image detail, eliminate the noise, also has strong anti-chirp ability; Based on the Hough transformation seeking angle of tilt, after uses the method which two times transform to cause the distortion of correction the image to be small; After refinement processing, uses the template match method to be possible distinguish the car license character fast andaccurately and so on.Key words: License Plate Recognition System, binaryzation, refinement, template match method目录第一章绪论. 51.1车牌识别项目系统概述 . 51.2车牌识别项目的意义 . 51.3车牌识别项目研究现状 . 61.4本文的研究内容 . 8第二章图 像预处理 . 102.1 BMP图像的读取与转换 . 102.2彩色图像灰度化 . 122.3去噪处理 . 132.4灰度图像的二值化 . 14第三章 图像校正 . 163.1图像倾斜角度检测 . 163.2车牌图像校正 . 163.2.1车牌图像校正方法 . 163.2.2车牌图像校正的流程 . 183.2.3车牌图像校正应用 . 20第四章字符分割 . 214.1车牌字符分割 . 214.1.1消除车牌边框 . 214.1.2车牌中字符的分割 .