Image difference watermarking algorithm based on Contourlet high frequency region

This paper proposes an image difference watermarking algorithm based on Contourlet high-frequency region. The algorithm selects two high-frequency directions to embed the watermark, compares the coefficient values of the corresponding positions in the two directions, and then embeds the watermark in combination with quantitative embedding. Experimental results show that the algorithm improves the robustness of the watermark algorithm on the basis of ensuring the invisibility of the image.