一种基于小波分块的自适应数字水印

为了在不破坏原始图像质量的情况下嵌入更多的水印,即较好地解决水印算法的不可见性和鲁棒性这对矛盾,本文提出了一种基于小波分块的自适应算法.先将水印进行置乱,提高安全性和抗剪切的鲁棒性.然后根据小波变换后,高、低频的特点,把水印以不同强度自适应地嵌入其中.实验结果表明,该算法不但具有较高的安全性,而且在增加了水印容量的前提下,图像的质量降低很小,很好地统一了水印算法的不可见性和鲁棒性.

Adaptive digital watermarking based on wavelet blocks

In order to provide more watermarks and to minimize the distortion of the watermarked image,an adaptive technique based on wavelet blocks is presented in this paper.We scramble the watermark to ensure the higher security and the robustness to cropping.We embed the watermark in the DWT with different intensities according to the different characteristics of the high and the low frequency.Experimental results indicate that the technique has higher security,larger capacity and less distortion.It ensures the robustness and imperceptibility of watermarking.