基于块效应谱分析的JPEG图像旋转角度估计  

Rotation Angle Estimation of JPEG Images Using Block Artifact Spectrum Analysis

作　　者：党良慧 张玉金 DANG Lianghui;ZHANG Yujin(School of Electronic and Electrical Engineering,Shanghai University of Engineering Science,Shanghai 201620,China)

机构地区：[1]上海工程技术大学电子电气工程学院,上海201620

出　　处：《电子科技》2023年第9期41-49,共9页Electronic Science and Technology

基　　金：上海市自然科学基金项目(17ZR1411900)。

摘　　要：图像旋转可以使图像伪造在几何角度上更加逼真,现有JPEG图像旋转角度估计算法的性能易受到块效应干扰和图像块尺寸大小影响,且对于旋转角度区间为[1°,15°]的估计仍然较为困难。文中提出了一种基于块效应谱分析的JPEG图像旋转角度估计算法:首先,使用变异蚁群算法提取图像的边缘并将其移除以突显块效应,并通过交叉差分进一步减轻图像纹理的影响;然后,通过设定合理的阈值和使用高斯高通滤波器移除傅里叶变换域的无关峰值,以减少干扰;最后,将傅里叶频谱的幅值分量投影到极坐标中,并将极坐标中峰值对应的极角作为旋转角度的估计值。实验结果表明,针对旋转角度位于[1°,15°]区间内的小尺寸JPEG图像检测,文中所提方法比现有方法具有更低的平均绝对误差。此外,当压缩质量因子逐渐下降时,文中所提算法的性能仍然优于现有方法,对JPEG压缩具有更好的鲁棒性。Image rotation makes fake images more realistic in geometric perspective,and the performance of existing JPEG image rotation angle estimation algorithms is easily disturbed by block artifacts and the image block size.It remains an imminent and challenging work for the rotation angle interval[1°,15°].This study presents an effective algorithm to estimate the rotation angle of JPEG images based on block artifact spectral analysis.Firstly,the edges of the image are extracted and removed using a variant colony algorithm to highlight block effects.Secondly,the effect of image texture is further mitigated by cross-differentiation.Thirdly,extraneous peaks are removed in the Fourier transform domain by setting reasonable thresholds and using a Gaussian high-pass filter to reduce interference.Finally,the amplitude component of the Fourier spectrum is projected into the polar coordinates,and the polar angle corresponding to the peak in the polar coordinates is the estimation of rotation angle we need.The experimental results show that the average absolute error of the method is lower than that of the existing methods for the detection of small-size JPEG images whose rotation angle lies within the[1°,15°]interval.Besides,when the compression quality factor is gradually reduced,the performance of the proposed method is still better than the existing methods,and the robustness of the proposed method to JPEG compression is better.

关 键 词：图像旋转角度估计 重采样 JPEG图像块效应 变异蚁群算法 谱分析 图像篡改 图像取证 JPEG压缩 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]