相干增强扩散与冲击滤波相结合的指纹增强算法  

Fingerprint Enhancement Using Shock Filter With Coherence Enhance Diffusion

作　　者：鲁伟[1] 

机构地区：[1]太原理工大学信息工程学院

出　　处：《科学技术与工程》2017年第8期208-212,共5页Science Technology and Engineering

基　　金：国家自然科学基金青年项目(61403273);山西省基础研究计划青年项目(2014021022-3;2014021022-4;2014021022-6)资助

摘　　要：自动指纹识别系统(AFIS)的性能严重依赖于输入指纹的质量,因此有效指纹增强算法对该系统具有重要意义。针对相干增强扩散滤波增强的指纹图像会出现边缘模糊,以及谷线与脊线间对比度较低的现象,提出使用冲击滤波和相干增强扩散的加权模型方法,既能保持相干增强扩散的优势,又能锐化指纹脊线边缘,以及增强指纹脊线与谷线的对比度。增强的主要过程为,建立一个相干增强扩散和冲击滤波的加权组合模型,加权函数是以指纹梯度为自变量,使得在扩散过程中在图像边缘处以冲击滤波为主,在脊线与谷线内部则以相干增强扩散为主。实验表明,使用这种方法,能得到更加清晰的指纹图像,便于之后的二值化与细化过程处理,使得自动指纹识别系统具有更好的性能。The performance of automatic fingerprint identification system is heavily determined by the quality of the input image, thus an effective method to enhance the fingerprint image is essential in such a system. Since the method of fingerprint image enhancement of coherence-enhancing diffusion has the disadvantages that the enhanced image will appear blurring edges and low contrast between ridges and valleys of fingerprint images, a new method combining coherence-enhancing diffusion and shock filter is put forward which can not only maintain an advantage of coherence-enhancing diffusion, but sharpen edges and enhance the contrast between ridges and valleys. Thus no-vel approach comes out. First, a weighting model of combining coherence-enhancing diffusion with shock filter is bulit, which emphasizes particularly on shock filter at edges while on coherence-enhancing diffusion at the other part, and gradient is taken as automatic variable of weighting function. Experimental results show that the proposed combining approach can obtain a more clear fingerprint image which is convenient to the process of binarization and thinning and finally achieve a better performance of the system.

关 键 词：相干增强扩散 冲击滤波 指纹增强 加权模型 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]