【正文】 icense plate identification。研究結果表明車牌識別率較高，適應性較強，實時性比較好。采用模板匹配法對車牌字符進行識別。 本文采用直方圖變換、邊緣檢測、二值化等方法對車牌圖像進行了預處理。所以說解決多路徑識別問題在完善高速公路聯(lián)網(wǎng)收費系統(tǒng)中起著至關重要的作用。1 畢業(yè)設計（論文） 課題 名稱 多路徑識別算法的研究 院別： 電氣工程學院 專業(yè)： 電子信息工程 2 摘要 隨著各省市高速公路的不斷建設，基本上建成了大小規(guī)模不等的聯(lián)網(wǎng)收費系統(tǒng)，在聯(lián)網(wǎng)收費系統(tǒng)建設中，都面臨了一個共同的問題 —— 車輛行駛路徑的識別。路徑識別不僅僅涉及對每一通行車輛如何計算通行費，同時還要考慮將收入的通行費拆分給哪個收費單位的問題，通行費的拆分直接 關系到各條高速公路的合法利益，是聯(lián)網(wǎng)收費的關鍵。 本文介紹了多路徑識別的多種算法，并著重分析了識別算法中的汽車牌照識別，根據(jù)車牌圖像特點，對車牌識別算法關鍵環(huán)節(jié)包括數(shù)字圖像預處理，車牌定位，車牌字符識別等三部分一一進行了分析研究。對車牌定位采用了一種基于灰度圖像求取卷積能量極值區(qū)域的車牌定位方法。并采用了 MATLAB 來完成算法的設計與實 現(xiàn)。 關鍵詞： 多路徑識別； 車牌識別；車牌定位；模板匹配； 字符識別 3 ABSTRACT As expressway construction unceasingly in provinces, numbers of online charging systems was pleted bascially. In the construction of online charging system, we are facing a mon problem — The identification of vehicle path. Path recognition involves not only how to calculate the tolls to every vehicle, also should consider how to split the ines to relevant charging unit. Toll split is directly related to the legitimate benifit of every expressway,and is the key to working toll. So solving the problem of multipath recognition plays an important role in perfecting the expressway working toll system. This article introduces the multipath recognition algorithms, And emphatically analysed the recognition algorithm of license plate recognition. Based on image characters of license plate, we have a deeply research on the key technologies of the vehicle license plate recognition system, which include three parts: digital image preprocessing, license plate location, license plate characters recognition. In the vehicle images preprocession, the paper use the methods of Histogram Transformation, Edge detection, binarization. For license plate localization using a kind of calculating convolution based on gray image energy extremum region of license plate locating paper use pattern matching which method has been improved to recognize the characters. And using MATLAB to plete the design and implementation of the algorithm. Research results show that the license plate recognition rate is higher, adaptability is stronger, better realtime performance. Key Words: Multipath recognition。 license plate location。 OCR 4 目 錄 第 1 章 緒論 ...................................................................................................................... 1 研究背景和意義 ......................................................................................................... 1 MATLAB 的概述 ........................................................................................................ 1 本文框架結構 ............................................................................................................. 4 第 2 章 國內外研究現(xiàn)狀 ............................................................................................... 5 國外研究現(xiàn)狀 ............................................................................................................. 5 國內研究現(xiàn)狀 ............................................................................................................. 6 第 3 章 多路徑識別算法的基本理論 ....................................................................... 8 多路徑識別方法的分類 ............................................................................................. 8 精確識別 ................................................................................................................... 8 概率識別 ............................................................................................................... 9 多路徑識別算法的理論基礎 ...................................................................................... 9 車牌照識別的主要算法 ...................................................................................... 9 本文采用的識別算法 ......................................................................................... 12 第 4 章 基于模板匹配的車牌識別詳細設計 ..................................................... 15 圖像采集 .................................................................................................................... 15 圖像預處理 ................................................................................................................ 15 車牌定位 .................................................................................................................... 17 傾斜校正 .................................................................................................................... 18 字符分割 .................................................................................................................... 19 字符識別 .................................................................................................................... 20 字符識別流程概述 ............................................................................................. 20 本文 字符識別流程 ............................................................................................. 22 第 5 章 車牌識別系統(tǒng)在 MATLAB 工具下的實現(xiàn) ........................................... 28 實驗環(huán)境 .................................................................................................................... 28 平臺搭建 .................................................................................................................... 28 識別過程 .................................................................................................................... 29 實驗數(shù)據(jù)及分析 ........................................................................................................ 34 第 6 章 總結與展望 ...................................................................................................... 36 總結 ........................................................................................................................... 36 展望 ...........................