A novel blind grayscale watermark algorithm based on SVD

In this paper a novel grayscale blind watermark algorithm based on SVD is proposed. The watermark signal is (64 times 64 times 8) bit gray image. First, The watermark is performed by Arnold chaos encryption. Then, the original image is divided into blocks according to the size of the watermark; each block corresponds to each pixel value of watermark. Then with the SVD technology, the pixel value of watermark is embedded into the blocks of largest singular value by the quantization. And the watermark can be detected without the original image. The experimental results show that the algorithm is robust to common signal processing techniques and some geometric distortions, such as JPEG compression, add noise, cropping, rotating, scaling, filtering and so on.