提升方案小波和DCT下的图像盲水印算法

在研究HVS对图像掩蔽特性的基础上，提出一种基于提升方案小波和DCT的彩色图像盲水印算法．首先将宿主图像亮度分量进行基于提升方案的小波分解，然后对其较低频子带进行基于分块的DCT分解，最后将二值图像的水印信息嵌人到各分块DCT域的中频系数中．文中算法结合HVS的掩蔽特性，使得水印信息的嵌人能量具有自适应的特性，从而保证了所嵌人的水印在不可见性的前提下，对常见的一些图像处理操作具有很强的鲁棒性．实验结果验证了文中算法的有效性．

A Blind Image Watermarking Algorithm Based on Lifting Scheme Wavelet and DCT

Digital watermark technique is one of the most active research topics in the safety field of multimedia information. On the basis of research on invisibility of HVS for the image, this paper proposes a blind image watermarking algorithm based on lifting scheme wavelet and DCT. Its main ideas are as follows: (1) analyzing the luminance component of the host image by lifting scheme wavelet; (2) dividing the lower frequency subband into blocks and transforming every block by DCT into a coefficient block; (3) embedding the watermarking information of binary image into the middle frequency region of the coefficient block together with the invisibility of HVS. Because of using the invisibility of HVS, the algorithm makes the embedded watermarking energy in the coefficient block adaptable. The algorithm possesses very strong robustness for some common image processing operations. Simulation results show the feasibility of the method.