基于提升小波和奇异值分解的灰度水印算法*

以提升小波变换和奇异值分解的理论为基础，提出了一种新的基于LWT和SVD的灰度图像水印算法。该算法核心思想是先对载体图像进行分块；然后对每块二级LWT后的中高频带继续LWT；再对选取的各频带进行SVD，选取相应的奇异值组成新的矩阵，对新矩阵按规则分块，并再次SVD。通过两次分块、两次LWT和四重使用SVD构造矩阵的方法，有效地将抽取的奇异值重新分配和组合。最后将Logistic混沌置乱后的灰度水印信息加载到组合后的矩阵中。该算法以保证鲁棒性和透明性的良好平衡为前提，提高了嵌入的信息量。仿真实验表明，该算法

Gray image watermarking algorithm base on LWT and SVD

This paper proposed a gray image watermark algorithm based on LWT and SVD.Firstly,divided the original image into many blocks.Then implemented the middle-high frequency of two-level LWT with each block by LWT,and applied SVD to the selected sub-frequency,divided the new matrix constructed with singular values into many blocks by rule,which were decomposed with SVD again.Through twice partition blocks,twice LWT and the use of quartic SVD,the matrix would re-allocation and combination for extraction's singula...