Dual wavelet watermarking using principal component analysis

In this article, a new scheme of dual wavelet watermarking by applying principal component analysis is presented. First, we identify the two best sub bands of wavelet transform by considering the intensity variance of each sub band. These two sub bands are further transformed by 1-level wavelet transform. The embedding locations are obtained by experiment in a way that they would be compatible with the human visual system. Both watermarks are embedded within the selected sub bands with respect to their principal components. We take advantage of interleaving technique to improve imperceptibility of the algorithm. Experimental results show good robustness and security of the proposed method against various attacks such as JPEG compression, cropping, gamma correction and Gaussian filtering.