基于分块DCT和Tucker分解的彩色图像数字水印

提出了一种通过分块DCT和Tucker分解将水印信息同时嵌入彩色图像R、G、B通道的离散余弦变换(DCT)直流系数中的水印算法。首先对彩色图像R、G、B通道进行8×8分块DCT,然后将各分块系数矩阵的直流系数分量构成三阶张量,再经过Tucker分解后获得核心张量,通过在核心张量中嵌入水印信息使得水印信息同时扩散到三通道的直流系数中。通过实验表明,该算法对于压缩、噪声、滤波、缩放等攻击具有一定的鲁棒性。与传统的基于YCbCr颜色空间的算法比较,该算法具有更好的不可见性。

Color image watermark based on block-DCT and Tucker decomposition

This paper proposed a new color image watermarking algorithm, which embedded the watermark into the DC coefficients of R, G, B channels through block-DCT and Tucker decomposition. First applied 8×8 block-DCT to R, G, B channels respectively, and used the DC coefficients of each block to construct a 3-level tensor. Embedding the watermark into the core tensor, which was got from Tucker decomposition, can diffuse the watermark into the DC coefficients of R, G, B. The experimental results indicate that this algorithm is robust to compression, noise, filtering and geometric distortion. And the algorithm is better than the algorithm based on YCbCr color space in invisibility.