【正文】 摘 要 為了對(duì)車牌字符的識(shí)別，本文將 BP 神經(jīng)網(wǎng)絡(luò)應(yīng)用于汽車車牌的自動(dòng)識(shí)別，在車牌圖像進(jìn)行預(yù)處理后的基礎(chǔ)上，重點(diǎn)討論了用 BP 神經(jīng)網(wǎng)絡(luò)方法對(duì)車牌照字符的識(shí)別。 首先將訓(xùn)練樣本做圖像預(yù)處理，對(duì)車牌上的字符進(jìn)行分割，得到單個(gè)字符。對(duì)大小不一的字符做歸一化后，對(duì)字符進(jìn)行特征提取，把長(zhǎng)為 15，寬為 25 的歸一化后的圖像中的字符信息提取出來，圖像中白點(diǎn)置為 0，圖像中的黑點(diǎn)置為 1，這樣就得到了 15 25 的特征向量，這個(gè)特征向量記錄的就是字符的特征。把這個(gè)特征向量送到 BP 網(wǎng)絡(luò)中進(jìn)行訓(xùn)練，得到了訓(xùn)練好的權(quán)值，把他保存到“ ”和“ ”中。然后打開要識(shí)別的圖片（即車牌），對(duì) 圖像進(jìn)行預(yù)處理后就可以識(shí)別了。識(shí)別率也在 90%以上，表明該方法的有效性。 關(guān)鍵字： 車牌識(shí)別； LPR； 字符識(shí)別；特征提??； BP 神經(jīng)網(wǎng)絡(luò)； Abstract For the discernment to the number plate character, this text applies BP neural work to the automatic discernment of the automobile number plate, on the basis that the number plate picture goes on in advance treated , is it use BP neural work method to car discernment , license plate of character to discuss especially. Will train samples to do the pretreatment of the picture at first, character in number plate cut apart, get the individual character. After making normalization to the character not of uniform size, drew the characteristic to the character 15, wide to draw out for character information of 25 picture behind the normalization, picture white point it puts to be 0, black point of picture is it as 1 , receive 15* 25 characteristic vector quantity like this to put, what the vector quantity of this characteristic is written down is the characteristic of the character . Send the characteristic vector quantity BP work train, get good right value of training, keep him in and . Open picture (namely number plate) discerned to want, go on to picture in advance treated to can discern. The discerning rate is above 90% too。 show the validity of this method. Key word： The number plate discerning； The character discerning； LPR； The characteristic is drawn； BP neural work； 目 錄 摘要 ...........................................................................................................................Ⅰ ABSTRACT...................................................................................................................Ⅱ 第一章 概述 ...........................................................................................................1 基本概念 ................................................................................................1 字符識(shí)別簡(jiǎn)介 ........................................................................................2 字符識(shí)別發(fā)展概況 .....................................................................2 字符識(shí)別系統(tǒng)用到的方法 .........................................................3 字符 識(shí)別原理 .............................................................................4 國(guó)內(nèi)外研究現(xiàn)狀和發(fā)展趨勢(shì) ................................................................5 基于神經(jīng)網(wǎng)絡(luò)的字符識(shí)別系統(tǒng) ............................................................6 系統(tǒng)簡(jiǎn)介 ....................................................................................6 系統(tǒng)的基本技術(shù)要求 ................................................................7 系統(tǒng)的軟硬件平臺(tái) .....................................................................7 第二章 字符識(shí)別系統(tǒng)中的關(guān)鍵技術(shù) ..................................................................8 特征提取 ......................................................................................8 基本概念 ....................................................................................8 區(qū)域內(nèi)部的數(shù)字特征 .............................................................10 基于邊界的形狀特征 .............................................................13 神經(jīng)網(wǎng)絡(luò) ..............................................................................................18 人工神經(jīng)元 ............................................................................18 人工神經(jīng)網(wǎng)絡(luò)構(gòu)成 ................................................................22 人工神經(jīng)網(wǎng)絡(luò)的學(xué)習(xí)規(guī)則 ....................................................23 BP 神經(jīng)網(wǎng)絡(luò) ...........................................................................24 第三章 系統(tǒng)的實(shí)現(xiàn) ............................................................................................31 系統(tǒng)流程圖 ..........................................................................................31 程序?qū)崿F(xiàn) ..............................................................................................31 程序的總體框架 ..................................................................................36 第四章 系統(tǒng)使用說明、測(cè)試及注意事項(xiàng) ........................................................37 系統(tǒng)使用說明 ......................................................................................37 系統(tǒng)測(cè)試 ..............................................................................................39 數(shù)字識(shí)別 ................................................................................39 字母識(shí)別 ................................................................................40 漢字識(shí)別 ................................................................................40 車牌識(shí)別 ................................................................................41 注意事項(xiàng) ..............................................................................................41 第五章 結(jié)論和展望 ............................................................................................42 致謝 ...........................................................................................................................43 參考文獻(xiàn) ...................................................................................................................44 外文原文與譯文 .......................................................................................................46 ? 外文 原文 ....................................................................................................46 ? 譯文 ............................................................................................................57 本科畢業(yè)設(shè)計(jì) (論文 ) 第 1 頁(yè) 第一章 概 述 基本概念 隨著 21 世紀(jì)經(jīng)濟(jì)全球化和信息時(shí)代的到來，計(jì)算機(jī)技術(shù)、通信技術(shù)和計(jì)算機(jī)網(wǎng)絡(luò)技術(shù)迅猛發(fā)展，自動(dòng)化的信息處理能力和水平不斷提高，并在人們社會(huì)活動(dòng)和生活的各個(gè)領(lǐng)域得到廣泛應(yīng)用。高速度、高效率的生活節(jié)奏，使汽車