摘要
重采样是图像篡改中的一种典型操作,针对现有重采样伪作检测算法对于JPEG压缩格式的图像检测效果不理想,也无法准确估计其中的缩放因子的问题,提出了基于再采样的图像重采样检测算法。该算法先将待检验的JPEG图像以缩放因子小于1进行再次重采样,以削弱JPEG压缩对算法的影响,再利用重采样信号二阶导数具有的周期性来进行重采样操作检测。实验结果表明,该算法具有很强的抗JPEG压缩能力,同时能够准确估计真实的缩放因子。另外,该算法对于经过不同缩放因子而得到的图像进行合成时的重采样操作,也有明显的检测效果。
Resampling is a typical operation in image forgery, since most of the existing resampling tampering detection algorithms for JPEG images are not so powerful and inefficient in estimating the zoom factor accurately, an image resampling detection algorithm via further resampling was proposed. First, a JPEG compressed image was resampled again with a scaling factor less than 1, to reduce the effects of JPEG compression in image file saving. Then the cyclical property of the second derivative of a resampled signal was adopted for resampling operation detection. The experimental results show that the proposed algorithm is robust to JPEG compression, and in this manner, the real zoom factor may be accurately estimated and thus useful for resampling operation detection when a synthesized image is formed from resampled original images with different scaling factors.
出处
《计算机应用》
CSCD
北大核心
2014年第3期815-819,共5页
journal of Computer Applications
基金
国家自然科学基金资助项目(60862003)
科技部国际合作项目(2009DFR10530)
教育部高等学校博士点基金资助项目(20095201110002)
关键词
数字图像盲取证
重采样伪作检测
再采样
抗JPEG压缩
缩放因子估计
blind image forensics
resampling tampering detection
secondary resampling
JPEG compression resistance
scaling factor estimation
