基于半色调技术的印前图像篡改检测方法  

Copy-Move Forgery Detection for Pre-Printing Image Using Digital Halftoning Technology

作　　者：谢伟[1,2] 万晓霞[1,2] 叶松涛[3] 金国念[1] 

机构地区：[1]武汉大学印刷与包装系,湖北武汉430072 [2]中国摄影文化产业研究中心(武汉大学),湖北武汉430072 [3]湘潭大学信息工程学院,湖南湘潭411105

出　　处：《软件学报》2017年第7期1835-1846,共12页Journal of Software

基　　金：国家自然科学基金(61275172);国家重点基础研究发展计划(973)(2012CB725302);湖南省教育厅一般项目(15C1324)~~

摘　　要：印前图像特指图像数字排版经编辑确认后的数字印刷样张,其以栅格处理器分色后的加网二进制形式存储.数字样张一经确认,其来源的合法性便不受怀疑.但是,从印刷的整体流程来看,数字样张的存储、传输过程中仍有较大的篡改风险.现有的复制移动篡改检测算法存在特征维度高、计算开销大或检测率较低等问题,而且不适用于分色后的二进制样张.提出了一种基于半色调图像网点密度特征的Copy-Move篡改检测方法,该方法对分色处理后的CMYK目标图像进行半色调二值量化处理,采用滑动分块的方法对目标图像进行分块,通过提取图像块CMYK这4个通道的局部网点密度特征对图像块进行篡改检测.实验结果表明,该方法在图像篡改检测上与以往方法相比具有较低的时间复杂度和较高的检测率,并且对图像篡改区域的旋转攻击、小尺度缩放攻击等具有较好的鲁棒性.Pre-Printing image is referred to as digital print proof validated by copy-editor. This type of image is stored in binary screened form after being processed by raster image processor （RIP）. It has indubitable legitimacy once the digital print proof is finalized. Looking at the overall printing flow, however, pre-printing images are still at the risk of malicious tampering in the storage and transmission process. Most of existing copy-move forgery detection methods employing high dimensional feature vector have high computational complexity, thus are not applicable to color separated binary screened proofs. In this paper, a new approach for copy-move forgery detection is proposed based on digital halftoning technology. The original image is binarized via digital halftoning technique in CMYK color space, which is similar to raster image processor. Then the halftone image is tiled to overlapping blocks, and the local screen density features of halftone overlapping blocks in CMYK channels are extracted for copy-move forgery detection. Experimental results demonstrate that the proposed method is able to detect copy-move forgery regions precisely, and it is robust to rotation and small scale zooming attacks to forgery regions.

关 键 词：复制移动 篡改检测 半色调 数字图像取证 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]