一种新的基于小波变换与混沌加密的彩色数字水印算法

提出一种新的基于小波变换与混沌加密的彩色数字水印算法 ,将混沌算法产生的阵列作为密码对水印图像进行加密 ,同时利用人类视觉系统HVS的特性 ,实现了水印的自适应嵌入 .在兼顾鲁棒性和不可见性的情况下 ,提出将水印按不同比例的方法 ,分别嵌入到小波域的低频和中频 (或高频 )子带中 ,在提取时根据低频子带提取的水印信息对中频或高频子带的信息进行调整 ,从而恢复出更加清晰的水印图像 .实验结果表明算法同时具有很好的鲁棒性和不可见性

A novel algorithm of digital watermarking for color images based on wavelet and chaotic encryption

An algorithm of digital watermarking for color images based on discrete wavelet transform (DWT) and chaotic encryption is presented in this paper, which employs one kind matrix generated by chaotic algorithm as a cipher to encrypt the watermark. At the same time, the characteristics of human visual system (HVS) is utilized to embed the watermarks into an image adaptively. By considering both robustness and invisibility, the watermarks with different proportions are embedded into the low and medium frequency subands in DWT domain. The information obtained from the medium or high frequency subands is adjusted by using the information obtained from the low frequency subands when extracting the watermarks so as to reconvert a clearer watermark image. The experimental results indicate both the robustness and the invisibility of the proposed algorithm.