一个基于三值位平面分解的盲数字图像水印算法

为了有效地保护数字图像的知识产权,提出一种新的、基于三值位平面分解的数字图像盲水印算法.对原始图像进行3级小波分解,将待嵌入的水印图像按高斯—拉普拉斯金字塔分解方法分解成3层.为了减少误差,不直接将分解得到的图像作为水印,而是保留前两层差值矩阵中的负值,并对这两个含有负值的矩阵进行三值位平面分解,将分解得到的位平面作为嵌入水印的掩码信息,用三值系数抖动调制的方法嵌入到相对应的分辨率层次原始图像之中.实验结果证明,该方法在减少提取水印的误差方面效果显著,而且有很好的抗JPEG压缩特性,对常见的图像处理攻击也有较好的稳健性.

Blind digital image watermarking method based on 3-byte bit decomposition

In o rder to pro tect copyright of digi tal image effectiv ely, a new blind digi tal imag e w atermarking method based on 3-by te bi t decompo si tio n w as pro po sed. Fi rst ly, the host imag e w as t ransfo rmed into three lev elled w av elet domain. Then th e wa termark was decomposed into a multi resolutio n hierarchical st ructure by the Gaussian-Laplacian py ramid decompo sitio n. In order to decrease the ex tractio n erro r, the decomposed imag es was no t ado pted as w atermarks di rectly. Instead, the minus v alues o f the pixel ma trixes w ere reserved and decompo sed based on 3-by te bit decomposi tio n. Last ly , these 3-by te bi tplanes w ere embedded into the co rrespo nding reso lutions of the decompo sed original imag es. The experimental resul ts demonst rate tha t the pro po sed algo ri thm ha s g ood performance in decreasing the ex tractio n error and has g ood ro bustness to JPEG compressio n and fami lia r at tacks to imag e.