畢業(yè)論文-基于Matlab的指紋識(shí)別.doc

First compliance review of the application of the appraisal Committee, only through the compliance review of the application to take part in a detailed review. 8.1 application compliance review: does not meet one of the following conditions, procuratorial Agency to submit application through compliance reviews, be invalidated: (1) application of the formats, contents, meet the requirements of selected files, powers of Attorney, declarations by the legal representative and the tender agent application to meet the requirements; (2) licence and a bidding agent qualifications meet the requirements; (3) the similar project tendering agency agent number and provide proof of material compliance; (4) the tendering Agency intends to put into this project the number of professionals to meet the requirements; (5) are intended to the agent of the project as a project manager has similar projects the number of and references to meet the requirements; (6) no fraud case. 8.2 application review in detail the Evaluation Committee through compliance reviews will be selected for detailed review of the application. 8.2.1 tender agent institutions similar project tender performance requirements (16 points) tender agent institutions similar project tender performance 16 points, by two part composition (1) agent similar project of cumulative bid amount scored calculation rules for: Agent water project bid amount (on January 1, 2007 has has bid notice for associate) cumulative each reached 100 million Yuan have 2 points, water project cumulative bid amount scored up not over 6 points. In addition, completes a bid worth more than 500 million yuan in total 1 minute, but other items score accumulated winning amount up to a maximum of 6 points. (2) calculation rule for the number of agents similar projects: proxy bid amount (since January 1, 2007 winning notice shall prevail) bidding projects in more than 50 million Yuan by 2 points, but the Agency projects the number of scores up to 3 minutes. 8.2.2 to be agents of the construction project as a project manager in the same project performance (10 points) Project Manager agent performance scores including agents of the bidding agencies of similar projects, as well as in other similar project tendering agency service agent during performance. Total 10 Project Manager agent performance, made up of two parts (1) acting like the accumulated winning amount calculation rule: agents for water conservancy project bid amount (since January 1, 2007 winning notice for example) cumulative average reached 100 million Yuan 3 but scored no more than 5 minutes. (2) calculation rule for the number of agents similar projects: proxy bid amount (since January 1, 2007 winning notice for example) in the more than 50 million Yuan water conservancy project period of 3 minutes, but scores the number of agents similar projects up to a maximum of 5 points. Project Manager demonstrated to provincial-level and higher peoples Government or the development and Reform Commission published the winning bidder on the designated media publicity shall prevail. 8.2.3 staff requirement (25 points) 1, to the construction project serving personnel, 4 years experience in tendering agent, 2 points per person, 2 years experience in tendering agent .Pig is not a pig. With domestic international market and technology big environment of changes, as China traditional industry of pig production of job way and profit way are requirements related industry for resources integration, to quality security for premise, regulation based farming, and management cost and the production, and sales cost, go standardization, and scale, and intensive, and market road, fast upgrade whole industry chain of regulation capacity, market competition capacity and anti-risk capacity. First, industry analysis (a) the basic situation in China is a traditional hog production and consumption country, 2008 46.15 million tons of pork, pig stock 462.64 million head by the end pig slaughter 609.6 million. National pig industrys annual production value at around 650 billion yuan, nearly 50% per cent of annual output value of animal husbandry. Sichuan province in 2008 produced 6.52 million tons of pork, with 694,000 tons of Chengdu city, live pig sell 10.46 million, first 15 Vice-provincial cities in the country. The whole nation advantage regional planning (2008-2015) there are 437 counties (cities), 55, Sichuan, Chengdu has 7 (including in pengzhou). International pig industry mainly include the European Union, the United States, and Canada, and Brazil and other absolute scale of animal husbandry industry and technology developed countries. Market 1, the domestic market from Chinas meat consumption habits and economic analysis of the development situation, the emergence of new trends in the market of domestic pork and its products. Docking is a pig production and sales more closely. The Yangtze River Delta, Pearl River Delta and the Bohai rim economic developed area industrial structure adjustment gathered pace, two or three industries to the Central and Western bias. Second, the rigid domestic consumption growth. For a long period, pork is still the largest variety of meat consumption in China, the absolute consumption continues to grow. Especially in the vast rural market growth potential. Third, market for pork and higher product quality requirements. Pollution-free pork safety and health has shown a very good market prospects. Four is the market changing. Currently, cold meat, more and more varieties of meat and pork meat products, which accounted for a large proportion of pork consumption, stores, chain stores, supermarkets and other marketing methods is on the rise, and transport has been extended to more than 2000 km in RADIUS. Chengdu is an important River pig resource market, the citys commercial rate reaches above 60% of live pigs, pork and raw materials primary processing products in the domestic and international reputation is high. Western hog trading center in Chengdu and provides disease-free areas of construction in order to further accelerate the development of swine industry realizes space and conditions. 2, the international markets at present, annual volume of trade in live pigs in the world year around 18 million, about 6 million tons of pork trade. A large net exporter of pork is mainly the EU and North America,-importing countries mainly in Asia, Japan, and Korea, and Singapore, the Philippines, Hong Kong and other countries and regions, as well as Russia, about 3 million tonnes were imported. It is predicted that the world meat consumption increase of 80% in Asia in the future, our country has obvious geographical advantages, export potential. With the advancement of live pigs superiority industry belt construction, animal disease .畢 業(yè) 論 文基于Matlab的指紋識(shí)別姓 名 院（系） 專業(yè)班級(jí) 學(xué) 號(hào) 指導(dǎo)教師 職 稱 論文答辯日期 學(xué)生承諾書本人鄭重聲明：所提交的學(xué)位論文，全部是本人在指導(dǎo)教師的指導(dǎo)下，和同學(xué)們的協(xié)助下獨(dú)立完成的工作研究成果。文中除了特別標(biāo)注和致謝的地方外，學(xué)位論文中不包含其他人或集體已經(jīng)發(fā)表或撰寫過的研究成果。對(duì)本文的研究做出重要貢獻(xiàn)的個(gè)人和集體，均已在文中以明確方式標(biāo)明。本人完全意識(shí)到本聲明的法律結(jié)果由本人承擔(dān)。 簽名：_日期：_摘 要隨著科學(xué)技術(shù)的不斷發(fā)展，自動(dòng)化的指紋識(shí)別技術(shù)如今已經(jīng)被人們廣泛地應(yīng)用在銀行、商業(yè)交易、公安部門、海關(guān)部門等需要對(duì)人的身份進(jìn)識(shí)別的領(lǐng)域，而本文所描述的是對(duì)自動(dòng)化指紋識(shí)別系統(tǒng)的研究現(xiàn)狀以及自動(dòng)化指紋識(shí)別系統(tǒng)的基本算法和流程，本實(shí)驗(yàn)是利用MATLAB2012來進(jìn)行了指紋識(shí)別系統(tǒng)的仿真和實(shí)驗(yàn)的。然而在生物識(shí)別技術(shù)的快速發(fā)展的今天，人們通過研究發(fā)現(xiàn)了每一個(gè)人的指紋都具有唯一性和不變性。也正因?yàn)檫@樣，指紋識(shí)別技術(shù)正在逐步的發(fā)展成為一種新的身份識(shí)別技術(shù)，并且憑借它良好的安全性以及可靠性，逐步有取代傳統(tǒng)身份認(rèn)證的方式趨勢(shì)。本文簡單的介紹了指紋識(shí)別圖像的預(yù)處理的方法和步驟。指紋圖像預(yù)處理之后將會(huì)得到一個(gè)寬度為統(tǒng)一像素的細(xì)化后的二值化圖像，最后再根據(jù)特定的指紋圖像的端點(diǎn)以及交叉點(diǎn)的特征進(jìn)行對(duì)指紋自動(dòng)匹配。本論文中采用MATLAB2012編程實(shí)現(xiàn)所有算法。關(guān)鍵詞：指紋識(shí)別技術(shù) 指紋圖像預(yù)處理 指紋識(shí)別 MATLAB20124.1 application of the Chinese language application for proxy bidding agency application system. 4.2 bidding agent applications should be submitted by the Agency included in the 5th chapter of the content, and than select file asked to provide appropriate documentation. 4.3 proxy application shall affix its official seal coding and page by page in the specified location. Agent a copy of the application shall have to number the pages and signed original copy (copy) (including supporting documents), and copy should be exactly the same. 4.4 application there shall be no loose pages. 4.5 agent application should be complete with indelible ink (powdered) prints, the agent shall not alter any page of the application. 4.6 bidding agencies offer should be based on the interim measures for the management of tendering agents service charges (meter prices 20021980) rules of the Nineth, tender agent service charges using the difference progressive billing rate. Charges in accordance with the tendering agents service charges and, in conjunction with the provisions of the specific circumstances of the project shall not be floating up and down-floating range must not exceed 20%, otherwise the application cannot pass compliance checks, be invalidated. Due to bidding agency selection and principal-agent contracts signed during charging base bid amount has not yet been produced, it can only be according to the rates of price, bid and the bid amount determines after the end, controlled response rates calculated shall pay tender fee (tender agency fee accounts for the actual bidding agent item for fares). Than the selected person tendering agents service charge control the upper and lower limits, Cap for the State Development Planning Commission of the interim measures for the management of tendering agents service charges (meter prices 20021980) of tendering agents service fees under 100%, the lower limit for the State Development Planning Commission of the interim measures for the management of tendering agents service charges (meter prices 20021980) of tendering agents service fees under 80%. Tendering agents service charge base should include the following tenders: construction, supervision and material over the above tenders are expected to be important, with each tendering agency entrusted with tender bid amount as a base for a separate computation of tendering agents service fees. Tendering agents service fee payment in accordance with the General Office of the State development and Reform Commission on tendering agents service charge of notification on the relevant issues (the change price 2003857). Sale of prequalification documents and solicitation documents going to choose all, pricing should be based on the principle of profit not files, must not violate the relevant provisions in the price Department. 4.7 requirements in the form of application proxy application shall be prepared in the 5th chapter of the format. Application of various supporting documents should be requested by the selection of files grouped by order. Comparison and selection of the bidding agencies must provide supporting documents required by the file; the file you selected does not have the required supporting documents, bidding agency acknowledged the need to provide, or you can provide. Proxy application shall be bound, and page-by-page coded in the order. 5th chapter application format notes: bidding agent .45目 錄1 緒論11.1 生物特征識(shí)別的意義11.2 生物特征識(shí)別分類22 指紋識(shí)別的原理和方法52.1指紋識(shí)別的基本原理52.2指紋識(shí)別系統(tǒng)工作流程52.3指紋識(shí)別技術(shù)的方法72.3.1 神經(jīng)網(wǎng)絡(luò)指紋識(shí)別算法72.3.2 濾波特征和不變矩指紋識(shí)別算法72.3.3 指紋匹配算法93 指紋識(shí)別算法的實(shí)現(xiàn)103.1 指紋圖像的預(yù)處理103.1.1 圖像的平滑103.1.2 圖像的歸一化123.1.3 圖像的紋理方向133.1.4 圖像的二值化153.1.5紋線細(xì)化163.2 指紋圖像的特征提取和特征匹配193.2.1 特征提取193.2.2 特征點(diǎn)匹配204 系統(tǒng)實(shí)現(xiàn)224.1仿真實(shí)驗(yàn)前期準(zhǔn)備224.1.1 仿真實(shí)驗(yàn)的實(shí)驗(yàn)軟件224.1.2 仿真實(shí)驗(yàn)數(shù)據(jù)的選取224.1.3 仿真實(shí)驗(yàn)界面的設(shè)計(jì)234.1.4 仿真實(shí)驗(yàn)算法244.2 指紋圖像的預(yù)處理254.3 實(shí)驗(yàn)結(jié)果與分析314.4 實(shí)驗(yàn)結(jié)果分析與總結(jié)405 小結(jié)41參 考 文 獻(xiàn)Abstract致 謝仲愷農(nóng)業(yè)工程學(xué)院畢業(yè)論文(設(shè)計(jì))成績?cè)u(píng)定表1 緒論如今，生物特征識(shí)別領(lǐng)域中的最為成熟的應(yīng)用技術(shù)之一-指紋識(shí)別技術(shù)。其實(shí)它已經(jīng)有非常悠久的歷史了。很久以前，指紋識(shí)別技術(shù)已經(jīng)很早就應(yīng)用于刑事偵查和司法鑒定領(lǐng)域了，很多人不知道的是。隨著計(jì)算機(jī)網(wǎng)絡(luò)和信息處理技術(shù)的快速發(fā)展，這門歷史悠久的指紋識(shí)別技術(shù)也開拓了更多更廣闊的市場(chǎng)，自動(dòng)的指紋識(shí)別技術(shù)和與其相關(guān)的產(chǎn)品越來越多的應(yīng)用在普通人的生活當(dāng)中。1.1 生物特征識(shí)別的意義生物識(shí)別技術(shù)（Biometric Identification Technology）的定義是：利用人體的不同的生物特征來進(jìn)行對(duì)人的身份進(jìn)行認(rèn)證的一種技術(shù)1。這是因?yàn)槿说纳锾卣魇俏ㄒ坏?，可以區(qū)分與他人不同的特征。并且我們還可以通過技術(shù)測(cè)量或者是自動(dòng)識(shí)別來檢驗(yàn)出生理特性以及行為方式，我們所說的這個(gè)特征分為生理特征、行為特征。我們對(duì)生物特性來進(jìn)行提取并放入數(shù)據(jù)庫，再將提取出來的人的唯一特征和它的身份一一對(duì)應(yīng)起來。典型的生物識(shí)別系統(tǒng)的主要系統(tǒng)結(jié)構(gòu)如圖1.1所示： 圖1.1 生物識(shí)別系統(tǒng)主要結(jié)構(gòu)框圖在當(dāng)今世界的很多計(jì)算機(jī)系統(tǒng)中，其中包含了很多非常機(jī)密非常軍方的系統(tǒng)，而這些系統(tǒng)都是簡單的使用“賬號(hào)戶名+密碼”的方式來進(jìn)行對(duì)用戶的身份的認(rèn)證以及訪問的控制。但事實(shí)上，這種設(shè)計(jì)方案卻經(jīng)常遇到一些很常見的問題。比如，設(shè)置的密碼容易被人們忘記，密碼太多一時(shí)容易混亂，而且與此同時(shí)，密碼畢竟不會(huì)很長很復(fù)雜所以也很容易被他人所竊取。而最重要的一點(diǎn)是，如果用戶一時(shí)間忘記了當(dāng)初他設(shè)置的密碼，他就不能進(jìn)入系統(tǒng)了，當(dāng)然忘記密碼可以通過身份認(rèn)證來重新設(shè)定密碼來恢復(fù)工作，但是這樣做很耗費(fèi)時(shí)間，而且身份認(rèn)證的手續(xù)麻煩，條件很多，這會(huì)給用戶帶來很多損失。很多有關(guān)機(jī)構(gòu)通過調(diào)查，表明了因?yàn)橛脩敉浢艽a而產(chǎn)生的一連串問題已經(jīng)成為阻礙人們生活的一個(gè)重要問題。人們而為了防止這類事件的頻繁發(fā)生，一種新的身份認(rèn)證手段便由此而生，這便是“人體的生物特征識(shí)別技術(shù)”。它的誕生是因?yàn)槊恳粋€(gè)人自身所具有的生物特征不同，而這種不同恰好可以對(duì)每個(gè)人的真實(shí)身份來進(jìn)行識(shí)別和認(rèn)證。然而我們的這些生物特征大部分都具備“人格各異”、“始終不變”和“隨時(shí)攜帶”的這三個(gè)主要的特點(diǎn)，然而這也確保了我們的生物特征識(shí)別技術(shù)的精確性以及可靠性。1.2 生物特征識(shí)別分類目前為止，有很多生物特征識(shí)別技術(shù)。但是，它們當(dāng)中有的已經(jīng)逐步得到應(yīng)用和推廣，而有的還僅僅處于實(shí)驗(yàn)研究的階段。(1)虹膜識(shí)別虹膜識(shí)別技術(shù): 利用人眼虹膜終身不變性，虹膜差異，為人類識(shí)別的技術(shù)是虹膜識(shí)別技術(shù)。虹膜識(shí)別技術(shù)與其相對(duì)應(yīng)的算法結(jié)合之后，可以達(dá)到很高的精度。 (2)視網(wǎng)膜識(shí)別視網(wǎng)膜識(shí)別技術(shù)：是使用激光照射在人的眼球背面，從中獲得具有唯一性的視網(wǎng)膜特征來進(jìn)行身份的識(shí)別。(3)面部識(shí)別面部識(shí)別技術(shù)：通過對(duì)人的面部表情特征，以及這些表情特征之間的相互關(guān)系，來進(jìn)行對(duì)比和識(shí)別的就是臉部識(shí)別。 (4)手寫體識(shí)別手寫體識(shí)別：所謂的手寫體識(shí)別就是將手寫的文字進(jìn)行數(shù)字化的一個(gè)過程，通過測(cè)量圖像本身以及寫字的動(dòng)作，以及在每個(gè)字母與字母之間，人們的用不同的速度、寫字不同的順序等來進(jìn)行識(shí)別的，手寫體識(shí)別和語音識(shí)別是一樣的，都是一種人體行為測(cè)定學(xué)。 (5)語音識(shí)別語音識(shí)別：語音識(shí)別的定義就是通過不斷地測(cè)量、通過記錄出語音的波形和聲音的變化特征，再根據(jù)現(xiàn)場(chǎng)所采集到的語音樣本和登記過的語音模板進(jìn)行的匹配，最后再通過計(jì)算機(jī)來進(jìn)行判斷。 語言識(shí)別和其他的行為識(shí)別技術(shù)一樣，因?yàn)槿说恼Z音變化的范圍太大，所以有時(shí)候而很難進(jìn)行一些精準(zhǔn)的匹配；同時(shí)語音還會(huì)隨著發(fā)音的音量、發(fā)音的速度和不同的音質(zhì)變化導(dǎo)致采集到語音會(huì)與要對(duì)比的模板有不同的結(jié)果。(6)基因識(shí)別DNA基因識(shí)別：基因識(shí)別是當(dāng)今世界最準(zhǔn)確的生物識(shí)別方法之一。但實(shí)現(xiàn)該技術(shù)所需的設(shè)備非常復(fù)雜而且非常昂貴，而且還需要專業(yè)的技術(shù)人員來進(jìn)行操作這些設(shè)備，而且基因識(shí)別所花費(fèi)的時(shí)間會(huì)很長，所以DNA基因識(shí)別技術(shù)到目前為止還不能廣泛的應(yīng)用在日常生活中。(7)指紋識(shí)別指紋識(shí)別技術(shù)：對(duì) “全局特征”、“局部特征”進(jìn)行分析的技術(shù)就是我們所說的指紋識(shí)別技術(shù)。而且我們每一個(gè)人的指紋都具有獨(dú)一無二的特征點(diǎn)，而且這些特征點(diǎn)都是可以測(cè)量的。每一個(gè)特征點(diǎn)還會(huì)伴隨著大概七個(gè)左右不同的特征?？上攵覀冇?0個(gè)手指，將產(chǎn)生至少4900的獨(dú)立功能并可以測(cè)量的數(shù)據(jù)。這將意味：指紋識(shí)別技術(shù)是一個(gè)門可靠的身份識(shí)別技術(shù)。根據(jù)不同的人的指紋也會(huì)有不同，即使是同一個(gè)人，也會(huì)有不同的指紋。而且紋線走向、紋線的斷點(diǎn)、交叉點(diǎn)的不同更加決定了指紋都具有“唯一”的這種特性，這恰恰就是指紋識(shí)別技術(shù)的原理。不僅如此，我們的指紋也是不會(huì)隨著我們年齡的增長而發(fā)生太大的變化，也就是說我們指紋是終生不變的。利用唯一性和穩(wěn)定性這個(gè)指紋的特性，可以將一個(gè)人身份個(gè)人信息和他所對(duì)應(yīng)的指紋聯(lián)系起來。實(shí)現(xiàn)的方法就是：通過對(duì)他的指紋樣本的預(yù)先保存，再和指紋模板進(jìn)行配對(duì)和比較。再利用計(jì)算機(jī)對(duì)指紋圖像進(jìn)行快速的識(shí)別。這樣就能很快的識(shí)別出指紋所對(duì)應(yīng)的的人的真實(shí)身份了。從而達(dá)到一種身份認(rèn)證和識(shí)別的功能。常用的幾種生物特征識(shí)別技術(shù)的技術(shù)性能比較如表1.1所示：表1.1 常用生物識(shí)別技術(shù)比較由表中很明顯得可以知道，指紋識(shí)別已經(jīng)是各種生物特征識(shí)別領(lǐng)域中綜合性能最好的技術(shù)之一。正因如此，指紋識(shí)別技術(shù)在當(dāng)今的身份認(rèn)證系統(tǒng)中被人們廣泛的應(yīng)用了。2 指紋識(shí)別的原理和方法2.1指紋識(shí)別的基本原理指紋識(shí)別技術(shù)其實(shí)是比較復(fù)雜的。自動(dòng)識(shí)別技術(shù)與人工識(shí)別技術(shù)的方式不同，很多掌握生物識(shí)別技術(shù)的公司并不是直接對(duì)指紋圖像進(jìn)行存儲(chǔ)的。而是多年來在各個(gè)公司及其研究機(jī)構(gòu)產(chǎn)生了很多數(shù)字化的算法。指紋識(shí)別算法最終還是歸結(jié)在指紋圖象上找到并比對(duì)指紋的特征。1指紋的特征總體特征和局部特征是我們用來定義指紋和識(shí)別指紋的兩個(gè)重要的特征。總體特征：那些光靠人的眼睛就可以很直接的區(qū)分到的生物特征被我們稱為是總體特征。環(huán)型、 弓型、 螺旋型這都是指紋的總體特征。而且其他的指紋螺紋圖案也都是基于這三種基本的螺紋圖案的。因此，僅僅依靠這三種基本的螺紋圖案來區(qū)分指紋是遠(yuǎn)遠(yuǎn)不夠的，但是，這樣做只是為了做一個(gè)粗略的分類，因?yàn)檫@樣就可以大大減少搜索數(shù)據(jù)庫時(shí)的工作量。局部特征：所謂的局部特征就是指紋圖像上的節(jié)點(diǎn)的特征，這些具有某種特征的節(jié)點(diǎn)我們稱之為特征點(diǎn)。我們知道：一般特征，有時(shí)兩個(gè)指紋是相同的，但我們正在談?wù)摰拇砭植刻卣鼽c(diǎn)的特征，這將是不同的。2指紋的特征點(diǎn)我們知道，手指的指紋的紋路并不是連續(xù)的，它們有些是打斷的，有些是光滑的，有些是彎的，有些是直的，有些是分開的。而這些指紋的斷點(diǎn)、 分叉點(diǎn)還有轉(zhuǎn)折點(diǎn)就被我們稱作為“特征點(diǎn)”。正因?yàn)橛辛诉@些特征點(diǎn)，才保證了我們的指紋是唯一的。2.2指紋識(shí)別系統(tǒng)工作流程讀取采集到指紋圖象、提取特征點(diǎn)、保存特征點(diǎn)數(shù)據(jù)和對(duì)特征點(diǎn)數(shù)據(jù)進(jìn)行比對(duì)是指紋識(shí)別技術(shù)主要的四個(gè)步驟。首先，指紋要通過指紋采集設(shè)備（Fingerprint acquisition device），常見的采集設(shè)備有光學(xué)取像設(shè)備、 超聲波掃描取像設(shè)備、 晶體傳感器等。其中，運(yùn)用的最多的是晶體傳感器。接著，將采集到的指紋圖像轉(zhuǎn)換為計(jì)算機(jī)內(nèi)可以識(shí)別的數(shù)字圖像就是我們所說的灰度圖。但是，由于我們?cè)诓杉^程中，難以避免因?yàn)槭种富蛘呤莾x器的原因，導(dǎo)致采集到圖像存在比較多的噪聲。所以，為了使我們采集到的圖像變得更清晰，以便于后續(xù)特征提取的操作方便，對(duì)指紋圖像進(jìn)行增強(qiáng)和濾波處理，處理后的圖像再進(jìn)一步的二值化、 細(xì)化5，是我們必須要做的事情。而這些步驟就被稱作是指紋圖像的預(yù)處理。然后，在細(xì)化后的指紋點(diǎn)線圖上提取出我們需要的特征值，刪去我們不需要的偽特征值，最終得到我們用進(jìn)行匹配的細(xì)節(jié)點(diǎn)。采集到的圖像細(xì)節(jié)點(diǎn)與模板中的細(xì)節(jié)點(diǎn)進(jìn)行比對(duì)，最終完成指紋匹配。本文著重研究了圖像預(yù)處理和細(xì)節(jié)特征提取這兩個(gè)關(guān)鍵部分。接著，一套用數(shù)字類型表示的指紋特征點(diǎn)數(shù)據(jù)就會(huì)錄入到計(jì)算機(jī)指紋識(shí)別軟件。這是一種只能由指紋信息轉(zhuǎn)換成特征點(diǎn)數(shù)據(jù)的單方向的轉(zhuǎn)換數(shù)據(jù)。對(duì)于不同的兩枚指紋，也會(huì)產(chǎn)生兩組不相同的特征數(shù)據(jù)。這就是識(shí)別軟件的數(shù)據(jù)點(diǎn)。它代表的是指紋的紋路上的交叉點(diǎn)、 斷點(diǎn)或者紋路圍圈處的位置坐標(biāo)信息。這些數(shù)據(jù)點(diǎn)就有七種以上對(duì)應(yīng)的的唯一特征。這些數(shù)據(jù)，就是模板，被保存為1K大小的記錄下來。最后，把兩個(gè)指紋的模板進(jìn)行比較，通過計(jì)算機(jī)來完成。再計(jì)算出這兩個(gè)指紋模板的相似程度。最終根據(jù)相似度得到兩個(gè)指紋的匹配結(jié)果。指紋識(shí)別系統(tǒng)框圖如圖2.1所示。圖2.1 指紋識(shí)別系統(tǒng)工作原理框圖2.3指紋識(shí)別技術(shù)的方法本文主要研究了：基于LVQ神經(jīng)網(wǎng)絡(luò)的識(shí)別算法。不變矩和濾波特征的指紋識(shí)別算法。指紋點(diǎn)模匹配算法這三種算法。根據(jù)我們已知的三種指紋識(shí)別算法，來進(jìn)行仿真實(shí)驗(yàn)，實(shí)驗(yàn)通過Matlab2012軟件完成，下面分別是這三種算法的優(yōu)缺點(diǎn)。2.3.1神經(jīng)網(wǎng)絡(luò)指紋識(shí)別算法選用哪種特征是神經(jīng)網(wǎng)絡(luò)識(shí)別方法中的關(guān)鍵性問題。通過分析同種類型的指紋，我們發(fā)現(xiàn)了這兩組指紋的差別主要體現(xiàn)在它們所對(duì)應(yīng)的每個(gè)細(xì)節(jié)點(diǎn)上。因此我們就提取了指紋的細(xì)節(jié)點(diǎn)特征，將這些細(xì)節(jié)點(diǎn)特征作為識(shí)別特征，再將每個(gè)樣本提取出來的細(xì)節(jié)點(diǎn)特征，構(gòu)造成一個(gè)801維的向量。這個(gè)向量包含了20個(gè)特征點(diǎn)，而每個(gè)特征點(diǎn)又包含了4維的向量。矢量化的LVQ神經(jīng)網(wǎng)絡(luò)模型是我們對(duì)特征點(diǎn)計(jì)算的手段?；谶@種方法的聚類特性和自組織特性，所以矢量化的LVQ神經(jīng)網(wǎng)絡(luò)模型可以很好地給出特性模式，通過多維空間的概率分布，來估算出指紋的匹配度。 其識(shí)別模型如圖2.2所示。圖2.2 基于神經(jīng)網(wǎng)絡(luò)的自動(dòng)指紋識(shí)別模型2.3.2 濾波特征和不變矩指紋識(shí)別算法本文所使用的主要算法是濾波特征和不變矩指紋識(shí)別算法。濾波特征識(shí)別算法：大小不變，不變的位置，方向不變，這是特征指紋圖像必須滿足的三個(gè)特點(diǎn)。大小不變性是很容易滿足的。而在濾波特征提取算法中，位置不變性，則是通過確定指紋圖像的中心點(diǎn)位置來實(shí)現(xiàn)的。通過在匹配階段，建立起多個(gè)角度的旋轉(zhuǎn)特征向量來實(shí)現(xiàn)指紋圖像的方向不變性。而濾波特征的提取算法，包括了4 個(gè)步驟。一是先確定指紋圖像的中心點(diǎn)。作為需要處理的指紋區(qū)域的中心位置，記為R01 區(qū)域；二是以中心位參考點(diǎn)，對(duì)R01 區(qū)域來進(jìn)行適當(dāng)?shù)膭澐?，得到一定大小的塊；三是運(yùn)用一組 Gabor 濾波器，對(duì)R01 區(qū)域做八個(gè)不同方向的濾波運(yùn)算；四是對(duì)濾波后的圖像，分別計(jì)算出每一塊中。圖像灰度值相對(duì)于均值的平均絕對(duì)偏差。 進(jìn)而得到特征向量或特征編碼。這種指紋識(shí)別算法。首先要對(duì)指紋圖像提取濾波特征，然后在特征向量上（由濾波特征值構(gòu)成的）進(jìn)行匹配。不變矩識(shí)別算法的基本思路是：1、 搜索預(yù)處理后的二值化圖像中，所有可能成為目標(biāo)的區(qū)域。2、 計(jì)算出R01區(qū)域中7個(gè)不變矩特征，求出與模板匹配程度最高的R01區(qū)域進(jìn)行匹配。其中相似度度量采用歐式距離（ Euclidean distance）。這里，搜索算法為系統(tǒng)使用的最簡單的順序查找方法。就是對(duì)數(shù)據(jù)庫文件，逐一搜索。一張指紋數(shù)字圖像圖片被系統(tǒng)讀入時(shí)，就會(huì)根據(jù)上述的方法，先對(duì)這一幅指紋數(shù)字圖像進(jìn)行特征值提取和編碼，并保存到臨時(shí)變量中去。系統(tǒng)的指紋數(shù)字圖像數(shù)據(jù)庫文件里同時(shí)也會(huì)保存一組指紋數(shù)字圖像灰度偏差的特征。過程如下：1申請(qǐng)內(nèi)存空間。將匹配結(jié)果的臨時(shí)變量進(jìn)行保存，對(duì)輸入系統(tǒng)的要匹配的指紋數(shù)字圖像的編碼進(jìn)行保存。2. 搜索系統(tǒng)的數(shù)據(jù)庫文件。當(dāng)數(shù)據(jù)庫文件為空時(shí)，程序結(jié)束查找。3. 當(dāng)系統(tǒng)的數(shù)據(jù)庫文件不為空時(shí)。由于在指紋數(shù)字圖像在入庫的時(shí)候，指紋數(shù)字圖像是按一定排列順序的編碼。同樣地，系統(tǒng)也將匹配的指紋數(shù)字圖像的圖象編碼設(shè)置同樣的順序。這樣系統(tǒng)就按照一定得順序進(jìn)行匹配。這樣可以通過歐氏距離（ E D）匹配算法，來判斷兩個(gè)指紋數(shù)字圖像之間的歐氏距離。前面提到系統(tǒng)是對(duì)一張指紋數(shù)字圖像進(jìn)行兩次編碼的保存。將相對(duì)應(yīng)的特征向量進(jìn)行比較，取其中最小的一個(gè)作為系統(tǒng)比對(duì)的結(jié)果輸出。這里是通過歐式距離來實(shí)現(xiàn)的對(duì)比數(shù)據(jù)庫中模板圖像和待測(cè)試圖像相對(duì)應(yīng)的特征點(diǎn)向量距離計(jì)算的。對(duì)于計(jì)算機(jī)計(jì)算出來的數(shù)據(jù)，如果匹配指數(shù)小于定值 T，則被認(rèn)為是匹配成功，否則匹配失敗。簡單的說，歐氏距離（ Euclidean distance）就是將兩組特征向量相減，然后求出他們對(duì)應(yīng)之間的差的平方和，然后開根號(hào)。舉個(gè)例子來說吧：A=（1，2，3）B=（4，5，6）則他們之間的距離就是 d=sqrt(1-4)2+(2-5)2+(3-6)2)。接著識(shí)別系統(tǒng)就逐一搜索數(shù)據(jù)庫中的數(shù)據(jù)文件，求的他們距離的最小數(shù)值。如果對(duì)比的兩張指紋數(shù)字圖像的特征向量之間的距離是 0，則系統(tǒng)會(huì)認(rèn)為這兩張數(shù)字圖像是同一張，或者說來自于同一手指。從而達(dá)到識(shí)別的功能。歐氏距離表示的是兩張指紋數(shù)字圖像的特征向量的相似程度。距離越近就越容易相互干擾，誤碼率也就越高，也就越相似。 2.3.3指紋匹配算法指紋匹配算法：是指在調(diào)整過程中的指紋特征值。它要匹配的是指紋圖像和預(yù)先存儲(chǔ)圖像特征值。英國的專家亨利認(rèn)為，只要13共同特征點(diǎn)存在的兩個(gè)指紋圖像的比例，就可以認(rèn)為這兩個(gè)要比較指紋圖像是相同的指紋。下圖2.3為指紋匹配算法的流程圖。圖2.3 指紋匹配算法的流程圖3 指紋識(shí)別算法的實(shí)現(xiàn)3.1 指紋圖像的預(yù)處理精確的指紋識(shí)別技術(shù)是非常依賴于脊的圖案信息來識(shí)別特征的細(xì)節(jié)結(jié)構(gòu)的。然而，在自動(dòng)指紋識(shí)別過程中，由于各種因素的影響手指本身的圖像，該指紋傳感器采集的原始狀態(tài)的指紋圖像將受到不同程度的干擾，并且圖像將通常包含大量的噪音，導(dǎo)致指紋圖像質(zhì)量嚴(yán)重下降。為了確保指紋圖像可以進(jìn)行有效的匹配過程。圖像預(yù)處理是自動(dòng)指紋識(shí)別系統(tǒng)中最重要的一步，圖像預(yù)處理的好壞會(huì)直接影響到指紋識(shí)別的好壞。預(yù)處理的目的是為了在圖像中除去噪聲，使圖像變成清晰的線，從而提高了指紋圖像可以被識(shí)別的有效區(qū)域的清晰度，方便指紋特征提取。而圖像的預(yù)處理大致可以劃分為以下幾步：灰度，平滑濾波，