Highly robust image watermarking in contourlet domain using singular value decomposition

In this paper, we propose a new method of image watermarking by using contourlet transform along with singular value decomposition. Contourlet transform is a new two-dimensional extension of the wavelet transform using multi-scale and directional filter banks. For security aspect of the watermarking algorithm and to improve imperceptibility of the algorithm, watermark bits are permuted by an interleaver. In embedding part, contourlet transform is applied to host image and appropriate direction is selected by considering intensity variance of all directions. Coefficients are modified by combining singular values of selected direction with singular values of watermark image. Experimental results show no visible difference between host and watermarked images. The proposed watermarking method is also robust to various attacks such as JPEG compression, rotation, histogram modification, Gaussian and median filtering and gamma correction.