A RSC Invariant Watermarking Scheme Utilizing Image Normalization for Synchronization

A rotation, scaling and cropping invariant watermarking scheme using image normalization is proposed in this paper. Watermark is adaptively embedded in discrete wavelet transform. Robust image feature points against rotation, scaling, noise and JPEG compression are obtained by the affine invariant Harris feature point detector and used to make the Delaunay triangle to estimate the affine transform parameters applied on the watermarked image through image normalization. Watermark extraction is carried out after watermarked image has been synchronized. Experimental results show that the proposed scheme can effectively resist rotation, scaling and cropping attacks as well as common signal processing.