Enhancing the robustness of Digimarc digital watermarking plug-ins in photoshop

Three methods are proposed in this paper to enhance the robustness of Digimarc watermarking plugins in Photoshop. They are decreasing image spectrum energy, magnifying watermarking noise and transfer watermarking information. The experimental results show that they can improve the robustness of the Digimarc watermarking plug-ins which the watermarking principle is unknown.