复杂背景上指纹图像增强方法比较研究  

Preferential Choices for Enhancement of Fingerprint Image with Complex Background

作　　者：王康宁[1] WANG Kangning(People’s Public Security University of China,Beijing 100038,China)

机构地区：[1]中国人民公安大学,北京100038

出　　处：《刑事技术》2020年第6期597-600,共4页Forensic Science and Technology

摘　　要：目的利用专业图像处理软件,通过数字图像处理的方法减弱或者去除背景图像对指纹图像的干扰。方法在运用配光检验方法获取指纹图像之后,主要运用图像对比度增强、图像锐化增强指纹图像,并运用同态滤波增强法、图像代数运算法等方法分离复杂背景,最后分析比较所用数字图像处理方法增强复杂背景上指纹的可行性及其增强效果。结果对比度增强和锐化处理等图像增强方法能够增强指纹纹线与背景之间的对比反差,明显减弱背景对指纹纹线的影响。采用Photoshop图层计算方法和MATLAB图像减法函数处理方法分离复杂背景均能获得较好的处理效果。运用同态滤波增强方法可以在一定程度将背景颜色去除,在适当的范围内调整不会改变图像的细节特征。结论单独或者联合使用本文所用图像增强方法后,能获得较好的处理效果,但具体选用何种方法处理要依具体情况分析。Objective To look for the means of lessening or even eliminating the background interference from fi ngerprint image with digital image processing.Methods Fingerprint image was obtained through adoption of light dispensing manipulation,having it undergone with Photoshop CS6 processing to highlight the fingerprint contour while reduce or even remove the background interference via the handling of image contrast enhancement/sharpening/smoothing/homomorphic fi ltering/algebra operation(MATLAB 2017b utilized,too).Finally,the feasibility and effect were compared among the digital image processing choices to enhance the fi ngerprint image with complex background.Results The choices of image contrast enhancement and sharpening have indeed intensifi ed the contrast difference between the fi ngerprint contour and background,capable of remarkably lessening the infl uence from background.Better processing effect has been obtained through separation of complex background from fingerprint image with either the Photoshop’s layer computation or the MATLAB’s subtraction function operating into image.To some extent,the homomorphic fi ltering enhancement removed the background out from fi ngerprint image,leaving the intact specifi cs of fi ngerprint image within an allowance of adjustment.Conclusion Better processing effect can be obtained for the fi ngerprint image with complex background to enhance its distinction by way of either single one or coalescent choices utilized here,yet with which and how many to choose depending on the specifi c situation.

关 键 词：指纹鉴定 数字图像处理 指纹图像 图像增强 复杂背景 

分 类 号：DF794.1[政治法律—诉讼法学]