Haar类正交变换在数字水印中的应用

Application of Haar Type Orthogonal Transforms in the Digital Watermarking

论文采取变尺度、多变换的策略,将Haar类正交变换应用于载体为图像的数字水印中。即不同的图像区域,子块尺寸不完全相同,相同尺寸的子块,所采用的正交变换不完全相同。实验结果证明:这种对图像采取分而治之的对策:不仅增强了水印的不可见性和鲁棒性,也提高了水印的抗攻击性,同时达到了图像高度压缩的目的。不仅如此,文中的正交变换的计算量小,均是即位算法,特别适宜并行计算。另外,文中水印为二值图像,且是盲水印。

Haar type orthogonal transforms are applied in digital watermarking by the technique of variable scales and different transforms in this paper,namely,the size of subblocks is not all the same with the same blocks,fast transforms adopt are not all the same even to subblocks with the same size either.The experiment results show that the proposed policy of dividing and rule is not only invisual to the image but also robust to attack,at the same time ,The method has high compression ratio.Furthermore,it's calcaulating quantity is very simple as well as it's computation speed is very fast because it's algorithm is in-place and special fit to parallel computation.Moreover,the image only having two values is taken as blind watermarking.