Rotation and scale insensitive image watermarking

Using electronic watermarks as copyright protection for still images requires robustness against attacks. In this paper we propose a watermarking scheme that is robust to rotation, scaling and translation (RST) distortions. The watermark is embedded in a 1D invariant domain that is a projection of the polar Fourier transform. Roc curves depicting false positives versus detection probability of the watermark are provided, under various geometrical attacks and JPEG coding.