一种抗几何失真的彩色图像数字水印算法*

提出了一种基于SIFT(尺度特征变换)特征点校正几何参数的小波域彩色图像水印算法.该算法利用RGB彩色图像中蓝色与绿色分量的小波系数之间的关系,在蓝色水平细节和垂直细节中嵌入相同的水印;水印检测前,利用红色分量中的SIFT特征点估计几何参数,校正失真水印图像,从而可以无失真地提取水印.实验结果表明,该算法对压缩、噪声、剪裁、旋转、缩放等各类几何攻击具有很好的鲁棒性.

Color image watermarking algorithm to resist geometric distortion

A color image watermarking algorithm in wavelet domain was proposed,which based on the SIFT (scale invariant feature transform ) feature points correcting affine factors. The algorithm made use of relations of DWT coefficients between blue and green components, and embedded watermarking messages into horizontal and vertical components of blue. Before watermarking detection, used stable SIFT feature points of red component to estimate geometric distortion factors and corrected watermarked image, then detected right watermarking messages. The experimental results show the algorithm is robust to compression, noise, and geometric attack such as cropping, rotation, scaling.