New blind watermarking scheme for digital image based on Contourlet transform and double encryption
基于双重加密和Contourlet变换的数字图像盲水印算法

In this paper, a blind digital image watermarking scheme by double encryption and Contourlet transform is proposed. Firstly, the watermarking is encrypted, then the original image is decomposed by using Contourlet, the low-pass sub-band and band-pass sub-band are required, then the relations between the Contourlet coefficient and the determinant is created. According to the relations, the watermark is embedded on the Contourlet low frequency coefficients. In addition, no host image is needed in watermark extraction, which is a blind watermarking algorithm. Experimental results show that the digital image watermarking has good imperceptibility and robustness against the attacks of JPEG compression, low-pass filtering, noise addition, scaling and cropping. The dual encryption of the watermark improves the security of the system.