一种基于模板匹配的车牌字符自动识别算法  

An Automatic License Plate Character Recognition Algorithm Based on Template Matching

作　　者：王志杨 刘金龙 WANG Zhi-yang;LIU Jin-long(Department of Electronics Engineering,Anhui Vocational College of Electronics&Information Technology,Bengbu,233030,Anhui;School of Electronics Engineering,Jiangsu Ocean University,Lianyungang,222005,Jiangsu)

机构地区：[1]安徽电子信息职业技术学院电子工程系,安徽蚌埠233030 [2]江苏海洋大学电子工程学院,江苏连云港222005

出　　处：《蚌埠学院学报》2024年第5期67-72,共6页Journal of Bengbu University

基　　金：安徽省高校优秀青年人才支持计划重点项目(gxyqZD2020073)。

摘　　要：针对现有车牌识别算法存在的环境适应性差,识别正确率低和识别时间过长的问题,提出了一种基于模板匹配的车牌字符自动识别算法。将所采集的车牌图像进行车牌定位、车牌预处理、车牌分割,实现车牌准确识别。车牌定位采用基于颜色的定位方式,并搜索区域内有效像素,保证定位成功。为了提升去噪性能,车牌预处理过程中采用了离散余弦变换和形态学处理技术。为了提高分割精度,利用水平投影获取上下边界,再利用垂直投影获取字符宽度后分割。最后采用模板匹配法识别车牌字符,缩短了识别时间。实验表明该算法运行时间短,识别正确率达到100%。According to the problems of poor environmental adaptability,low recognition accuracy,and long recognition time in existing license plate recognition algorithms,an automatic license plate character recognition algorithm based on template matching is proposed.The collected license plate images are subjected to license plate localization,license plate preprocessing,and license plate segmentation to achieve accurate license plate recognition.The license plate localization is based on the color localization method,and effective pixels within the area are searched to ensure successful localization.In order to improve the denoising performance,discrete cosine transform and morphological processing techniques are used during the license plate preprocessing process.In order to improve segmentation accuracy,horizontal projection is used to obtain the upper and lower boundaries,and then vertical projection is used to obtain the character width for segmentation.Finally,the template matching method is used to recognize license plate characters,which shortens the recognition time.The experiment shows that the algorithm has a short running time and a recognition accuracy of 100%.

关 键 词：车牌识别 图像处理 定位算法 字符分割 模板匹配 

分 类 号：TN391.41[电子电信—物理电子学] U495[交通运输工程—交通运输规划与管理]