基于Hermite滤波器的指纹增强算法  

Fingerprint image enhancement by Hermite filter

作　　者：王健康[1] 彭小奇[1,2] 钟云飞[2] 郭强[1] 

机构地区：[1]中南大学物理科学与技术学院,长沙410083 [2]中南大学信息科学与工程学院,长沙410083

出　　处：《计算机应用》2010年第7期1852-1854,1858,共4页journal of Computer Applications

基　　金：国家自然科学基金重点资助项目(60634042)

摘　　要：指纹增强的目的在于改善指纹图像的质量,以提高指纹识别系统的性能。提出了一种基于Hermite滤波器的指纹增强算法,算法利用经典的梯度公式法计算纹线方向,利用指纹图像子块的频谱分布特征计算纹线频率。以纹线方向和频率作为滤波器的主要参数,利用具有良好带通特性的Hermite滤波器和具有可变角度带宽的低通滤波器进行滤波,有效地提高指纹的纹理清晰度,较好地避免奇异点区域的块效应。实验结果表明,算法具有良好的图像增强效果。Fingerprint enhancement aims to improve fingerprint image quality,and enhance the performance of fingerprint recognition system.This paper proposed an approach to fingerprint image enhancement based on Hermite filter.The algorithm calculated ridge orientation by using gradient-formula method,and calculated ridge frequency by using the frequency spectrum characteristic of fingerprint image block.With ridge orientation and frequency as the main parameters of filter,the algorithm made use of Hermite filter with good band-pass property and made use of low-pass filter with changeable angle bandwidth to implement the filtering,enhancing the texture definition effectively and better avoiding blocking effect in singular point area.The experimental results show that the proposed algorithm achieves good image enhancement.

关 键 词：指纹增强 Hermite滤波器 奇异点区域 纹线频率 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]