文档介绍：摘要
随着交通拥挤和堵塞等各种问题的日益突出,以及计算机技术的不断发展,智能交通系统得到了越来越广泛的应用,尤其在欧、美等发达国家,而在我国的应用尚处于探索研究的起步阶段。车辆的自动识别是ITS的重要组成部分,可用于各类车辆管理场所,特别是高速公路智能控制,提高管理效率和水平,节省人力,物力,实现车辆管理的科学化,规范化。本论文在分析了各种车辆车牌信息特征的基础上,应用图像处理技术,包括汽车图像预处理,车牌定位,车牌图像分割和字符识别等,设计并实现了一个原始的车牌识别系统的仿真。
首先对摄像机采集的图像进行去除背景的运算以获取车辆图像,随后的工作是图像的预处理、特征提取、车牌图像分割、字符识别,以达到车牌识别的目的。
图像的预处理中首先用加权平均值法对图像进行灰度化处理,然后灰度值线性展宽,用中值滤波消除噪音,用Canny算子进行边缘检测。车牌定位时采用混合特征的多车牌快速定位方法。用改进的Otsu法进行二值化;采用模板匹配的方法进行识别。
关键字:图像预处理;车牌定位;车牌图像分割;字符识别
ABSTRACT
With the increasing problems in traffic management, the development puter technology has made the intelligent transportation system more and more applied. ITS have been widely applied in advanced country such as Europe and America. But in our country, the application of it is in research phase. Automatic identification and tracking of vehicles is an important part of ITS. This thesis analyzes various types of vehicle identification technology, and uses Image processing and pattern recognition technology plete vehicle identification.” Classification of the Toll for High way’s adopted in this dissertation as the vehicle classification standard.
First, the vehicle image was extracted from camera image after removing the background. Then this dissertation describes image pretreatment, feature extraction and pattern recognition algorithm, finally the type of the vehicle was obtained.
In the image preprocessing, using method of weighted average process image gray value, then using method of linear broaden process grey value, with a median filter eliminate noise, with Canny operator on edge detection; License plate localization based on hybrid features used more license plate quick location methods; With the improvement of OTSU method; Using the template matching method for identification.
Keywords:Image preprocessing; license plate location; license plate image segmentation; character recognition
目录
1. 绪论 1
课题的研究背景 1
车牌识别系统研究目的及意义 2
车牌识别系统的结构和工作原理 3
车牌识别技术的国内外研究现状 4
2. 车牌图像预处理 6
图像