Double watermarking algorithm based on support vector machine in complex Contourlet domain and Krawtchouk moment
WU Yi-qua · Journal of Optoelectronics·laser · 2014
In order to further improve the robustness of watermarking algorithm based on support vector machine(SVM),a double watermarking algorithm based on SVM in complex Contourlet domain and Krawtchouk moment is proposed in this paper.Firstly,the blue component and green component are extracted from the RGB host image.The algorithm makes full use of the invariance of Krawtchouk moment invariants to translation,rotation and scaling,and the better local reconstruction characteristics of Krawtchouk moment.The lower order Krawtchouk moment invariants of the blue component are calculated for construction of robust watermarking.Then the green component image is decomposed by two-level complex Contourlet transform.In the low-frequency components,the local correlation training model of image in the same scale is established by using support vector machine.The watermarking image is adaptively embedded and extracted according to the prediction results of the established model.A large number of experimental results show that the proposed algorithm is not only invisible but also robust against the common image processing,such as median filtering,Gaussian noise and JPEG compression,and against some kinds of geometric attacks,including rotation,scaling and clipping.It outperforms the image watermarking algorithm based on support vector machine in wavelet domain or Contourlet domain.