基于JPEG块效应差异的图像篡改区域自动定位  

Locate Tampered Image Region Automatically Based on Inconsistency of JPEG Blocking Artifacts

作　　者：王鑫[1] 鲁志波[2] 

机构地区：[1]信息工程大学应用数学系,郑州450002 [2]信息工程大学理学院数理系,郑州450001

出　　处：《计算机科学》2010年第2期269-273,共5页Computer Science

基　　金：国家科技支撑计划重点项目(2006BAK07B04);国家自然科学基金(60803155)资助

摘　　要：不同JPEG栅格位置或不同压缩质量的图像区域被合成为篡改图像时会出现JPEG块效应的差异,据此提出了一种能自动定位篡改区域的图像盲被动取证方法。算法先通过一种基于小波的图像去噪方法提取噪声,利用噪声衡量局部JPEG块效应以提高块效应信号的信噪比;然后通过迭代方法寻找到合适的阈值,在块效应直方图中分离出篡改区域。针对不同类型的篡改区域的实验说明了算法的有效性。Inconsistency of blocking artifacts is introduced when image regions with different JPEG quality factors or grids are spliced for forgery. A novel image forgery detection method was proposed to automatically locate the tampered regions. The compression noise was firstly extracted from the images using a wavelet-based denoising filter. The pro- posed method measured the JPEG blocking artifact using the compression noise to improve the SNR. Then an appropriate threshold was found using an iterative method to separate tampered regions in the histogram of blockiness metrics. Experimental results were presented to demonstrate the effectively and reliability of our method.

关 键 词：图像取证 图像篡改 块效应 JPEG 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]