Geometrically robust image watermarking based on polar complex exponential transform

In this paper, we propose a geometrically robust image-watermarking scheme based on Polar Complex Exponential Transform (PCET). First, the watermark is generated by modifying the vector formed by the PCET moments of an image, and watermark signal is designed with PCET moments. Then, the signal is added to the cover image in the spatial domain after an image reconstruction process. Finally, the watermark is detected by the shortest distance decode method. Simulation results demonstrate that the proposed method can effectively resist rotation attacks, scaling attacks and common signal processing attacks.