基于非线性扩散滤波的指纹增强算法  

Fingerprint Enhancement Algorithm Based on Nonlinear Diffusion Filter

作　　者：程建刚[1,2] 田捷[1,2] 何余良[1,2] 杨鑫[1,2] 

机构地区：[1]中国科学院自动化研究所复杂系统与智能科学重点实验室,北京100080 [2]中国科学院研究生院,北京100039

出　　处：《自动化学报》2004年第6期854-862,共9页Acta Automatica Sinica

基　　金：国家杰出青年科学基金(60225008)国家自然科学基金(60332010)国家自然科学基金青年科学基金(60303022)资助

摘　　要：根据指纹图像的特性提出了一种利用非线性扩散滤波增强指纹图像以提取细节点的方法．该算法利用指纹图像的结构张量构造扩散张量，使得滤波沿着指纹脊线方向扩散．在求解非线性扩散滤波中最重要是怎样选取迭代时间和迭代步长．为了解决这两个问题，根据扩散张量在大小为(2n+1)×(2n+1)窗口上的离散形式，分解扩散滤波为4n 个方向的和，然后利用托马斯-高斯消元法在每个方向快速求解非线性滤波后的指纹增强图像．该算法的优点是可以有效地连接断裂脊线，而不会改变指纹脊线的连续性和奇异性．在 NIST27数据库及 FVC2002数据库上的实验结果表明，基于非线性扩散滤波的指纹增强算法可以有效地提高提取细节点的性能和指纹匹配率．This paper proposes a nonlinear diffusion filter to enhance fingerprint image and extract the minutiae according to the characteristic of the fingerprint. The algorithm uses the structure tensor to construct diffusion tensor, and makes the filter diffuse along the ridge direction. In order to improve the computing efficiency, according to the discrete format of the diffusion tensor in a window size of (2n+1)×(2n+1), the diffusion filter is split into 4n directions, after that, in each direction the fingerprint enhancement image is computed with Thomas-Gaussian elimination algorithm. The advantage of this algorithm is to connect the breaking ridges in an effective way, and without changing the continuity and singularity of the ridge. Experiments on NIST27 and FVC2002 databases show that the enhancement algorithm based on nonlinear diffusion filter could improve the performance of extracting minutiae and correct fingerprint matching ratio.

关 键 词：指纹增强 非线性扩散 指纹细节点 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]