Contourlet based image watermarking scheme using Schur factorization and SVD

Abstract

In this paper, a novel image watermarking scheme is proposed, based on Contourlet Transform (CT) and Matrix Factorization methods namely, Schur Factorization and Singular Value Decomposition (SVD). The original image and watermark are both decomposed by CT. The lowest frequency coefficients of original image after CT are factorized using SVD and that of watermark after CT are decomposed by Schur Factorization. The schur form of watermark is further factorized using SVD. The modified coefficients of singular values of watermark are embedded in the singular values of original image followed by inverse SVD and inverse CT computation that results in the watermarked image. The experimental results demonstrate that the scheme is resistant against signal processing attacks such as median filter, salt and pepper noise, Gaussian noise, compression and geometric attacks. © 2012 ICST Institute for Computer Science, Social Informatics and Telecommunications Engineering.