指紋識(shí)別系統(tǒng)畢業(yè)設(shè)計(jì)


摘 要

由于指紋所具有的唯一性和不變性，以及指紋識(shí)別技術(shù)具有很高的可行性和實(shí)用性，指紋識(shí)別成為目前最流行、最可靠的個(gè)人身份認(rèn)證技術(shù)之一。
本論文對指紋圖像基于小波變換的各種處理進(jìn)行了分析、總結(jié)。圖像處理包括基于小波變換的指紋圖像濾波處理和基于小波的指紋圖像增強(qiáng)處理。同時(shí)介紹指紋圖像的預(yù)處理：目的是去除指紋圖像中的噪音，將其轉(zhuǎn)化為一幅清晰的點(diǎn)線圖，便于提取正確的指紋特征。它分四步進(jìn)行，即灰度濾波、二值化、二值去噪、細(xì)化。
本文針對基于點(diǎn)模式匹配的指紋匹配算法速度較慢的現(xiàn)狀,設(shè)計(jì)了一種新的指紋匹配方法,即利用紋線匹配技術(shù)來尋找基準(zhǔn)點(diǎn)對的指紋匹配算法.實(shí)驗(yàn)證明,該算法匹配速度很快,誤識(shí)率低,準(zhǔn)確性高,并具有圖象旋轉(zhuǎn)平移不變性.對面積適中的指紋圖象,匹配結(jié)果可以滿足在線應(yīng)用的需要.該算法有望發(fā)展成為一種實(shí)用、有效的指紋匹配技術(shù).

關(guān)鍵詞:指紋圖像增強(qiáng)，細(xì)化，特征提取，特征匹配，二值化，指紋圖像濾波

Abstract

Due to the uniqueness and invariability of fingerprints, and better feasibility and utility of fingerprint verification technology, the automated identification based on fingerprints is becoming an attractive alternative to the traditional methods of identification.
In this paper, we have analyzed the image processing of fingerprint images which are based on wavelets transforms. The image process is mainly composed of two sections, which are fingerprint filtering process and fingerprint the enhancement which are based on wavelets transform. At the same time, there to be introduce the fingerprint preprocess. The fingerprint preprocess is to remove noise and it will translate into a plain point-line image, which is convenient for extracting the perfect fingerprint character.
  Because the fingerprint matching algorithm based on point pattern matching is not quick enough, a new fingerprint matching algorithm is presented here. Lines matching technique is used in the algorithm for seeking pairs of reference minutiae. Through experiments, the algorithm is proved accurate, quick, and invariable to translation and rotation of images. According to fingerprint images of moderate sizes, the needs of online application can be met. The algorithm is expected to be a convenient and effective fingerprint matching technique.

Key words：fingerprint image enhancement ，feature extraction, feature fingerprint image compression thinning, matching,

目     錄

1 緒論
1.1 指紋自動(dòng)識(shí)別技術(shù)的歷史、現(xiàn)狀和未來…………………………………………1
1.2 本文的主要研究工作………………………………………………………………2
2       Visual C++環(huán)境下圖像的小波變換及指紋圖像處理
2.1 小波的基本理論………………………………………………………………3
2.1.1  小波分析圖像處理……………………………………………………3
2.1.2  連續(xù)小波變換…………………………………………………………5
2.1.3  離散小波變換…………………………………………………………6
2.1.4  指紋圖像二維小波變換概念及算法…………………………………7
2.1.5  二維小波變換編程實(shí)現(xiàn)及運(yùn)行結(jié)果…………………………………8
2.2 基于小波變換的指紋圖像濾波處理…………………………………………20
2.2.1   小波系數(shù)的頻域分布………………………………………………21
2.2.2   基于小波變換的圖像濾波處理……………………………………21
2.2.3   指紋圖像的低通濾波的實(shí)現(xiàn)及運(yùn)行結(jié)果…………………………21
2.2.4   指紋圖像的高通濾波及編程實(shí)現(xiàn)和運(yùn)行結(jié)果……………………25
2.2.5   指紋灰度圖濾波……………………………………………………30
2.2.6   方向加權(quán)中值濾波算法……………………………………………32
2.2.7   基于小波變換濾波處理的結(jié)論……………………………………36
2.3 基于小波變換的指紋圖像增強(qiáng)處理及實(shí)現(xiàn)…………………………………37
2.3.1 圖像增強(qiáng)及技術(shù)的基本思想…………………………………………37
2.3.2 基于小波的指紋圖像增強(qiáng)算法………………………………………38
2.3.3 指紋圖像增強(qiáng)處理的VC++編程實(shí)現(xiàn)及運(yùn)行結(jié)果……………………41
2.3.4 指紋圖像的平滑及VC＋＋編程實(shí)現(xiàn)…………………………………46
2.3.5 指紋圖像中值濾波及VC＋＋編程實(shí)現(xiàn)………………………………60
2.3.6 指紋圖像梯度銳化和拉普拉斯銳化…………………………………70
3 基于Visual C++指紋圖像的預(yù)處理
3.1 預(yù)處理概述…………………………………………………………………78
3.2 指紋方向圖及其提取算法…………………………………………………78
3.3 指紋圖像二值化及圖像濾波去噪…………………………………………82
3.4 指紋圖像細(xì)化及算法編程實(shí)現(xiàn)……………………………………………84
3.5 指紋圖像細(xì)化后去噪………………………………………………………91
3.6 本章總結(jié)……………………………………………………………………91
4 Visual C++環(huán)境下指紋特征提取及匹配
4.1 指紋細(xì)節(jié)特征提取…………………………………………………………92
4.2 指紋的細(xì)節(jié)匹配……………………………………………………………96
5     全文總結(jié)……………………………………………………………………………104
致謝…………………………………………………………………………………………105
參考文獻(xiàn)……………………………………………………………………………………106
附錄
英文原文………………………………………………………………………………107
漢語翻譯………………………………………………………………………………112