Robust Image Watermarking Algorithm Based on Radon and Analytic Fourier-Mellin Transforms

The most existing digital watermarking methods were robust to general attacks such as additive noise, image filtering, JPEG compression and so on, but resisting to geometric attacks is still a difficult challenge. This paper proposed a watermarking algorithm resisting to geometrical attacks. The Radon transform was employed to project two dimension image onto projection space. Then the rotation of this image was converted to a translation of the projection. At the same time, the scaling was converted to a scaling of the projection besides the scaling of the projection amplitude. After that, the analytic Fourier–Mellin transform was used to construct invariant moments. These invariant moments are used to design and detect watermark. The experiment demonstrates the proposed method was robust to usually image processing operation, and performed robust to geometrical attacks.