SVD based robust and secure dual stages watermarking scheme for copyright protection

In this paper, a robust and secure dual stages digital image watermarking scheme is proposed for copy right protection in SVD domain. In order to provide high security, the proposed scheme used Logistic map to encrypt the primary watermark and Arnold´s cat map to scramble the cover image. The proposed scheme also used singular value decomposition (SVD) technique to decompose the scrambled cover image, secondary watermark and encrypted primary watermark. The singular values (SVs) of the encrypted primary watermark are embedded into the SVs of secondary watermark by using a scaling factor. Then the SVs of modified secondary watermark are embedded into the SVs of scrambled cover image. The secondary watermark is only used to support the primary watermark against various attacks. The proposed scheme is tested using some ordinary image processing and geometrical attacks such as filtering, cropping, rotation, histogram equalization, blurring, resizing, salt & pepper noise and Gaussian noise etc. Analysis and experimental results show that the proposed dual stages watermarking scheme offers good robustness and high security than other related existing methods.