基于DWT-SVD和Fibonacci变换的彩色图像盲水印算法

为提高水印鲁棒性,将离散小波变换(DWT)、奇异值分解(SVD)和斐波纳契(Fibonacci)变换结合,提出一种新的算法。首先,用Fibonacci变换对拟嵌入的水印进行置乱处理;然后,对宿主彩色图像R、G、B三个分量进行二级小波变换和基于4×4分块的奇异值分解,并用混沌序列选择若干对子块;最后,根据人类视觉系统(HVS)特性对三个分量分配嵌入量、确定嵌入强度,并通过修改每对子块最大奇异值来实现水印嵌入。实验结果表明本方案具有良好的水印不可见性和鲁棒性。

Blind watermarking algorithm for color images based on DWT-SVD and Fibonacci transformation

To improve the robustness of digital watermark, this paper proposed a novel robust watermarking algorithm for color images based on discrete wavelet transformation DWT, SVD and Fibonacci transformation. Firstly, this algorithm adopted the Fibonacci transformation to scramble the original watermark before embedded. Then, it decomposed the R, G, B components of the host color image by 2-level-DWT, and partitioned the obtained sub-bands into non-overlapping blocks of 4×4 pixels and then applied SVD to the blocks. Meanwhile it used the chaotic sequence to select several couples of blocks. Finally, it determined the embedding capacity and the intensity of each component according to the characteristics of human vision system to meet the requirements of invisibility and embedded one bit of watermark by modifying the relative size of the first singular values of one couple blocks. Experimental results show that the proposed algorithm has a good performance in imperceptibility and robustness of watermark.