Istree Digital Watermarking Algorithm Based on Contourlet Transform

In order to protect the copyright of the image, in this paper proposed a novel important sub-tree (Istree) digital watermarking algorithm based on contourlet transform. First, Shuffling is applied by watermarking image for increasing robustness. Second, the original image are decomposed three levels by contourlet transform, and then analysis sub-bands in all directions, according to various levels sub-bands in all direction structure like tree. And find important sub-tree, then Scrambling after the watermark image sequence is embedded in important sub-tree. The experimental results show that the algorithm has a certain degree of robustness and can resistance attack.