High perceptual quality and robust color image watermarking scheme using Julian set patterns inDWT-SVD
Nagaraj V. Dharwadkar, B. B. Amberker · International journal of tomography and simulation · 2012
In this paper, we propose a non-blind color image watermarking scheme which use Julian set patterns and Singular Value Decomposition (SVD) in Discrete Wavelet Transformation (DWT) domain. Four watermark image patterns are generated using the Julian set pattern functions with different input parameters such as coefficients of function, an initial point and the number of iterations. These parameters will be used as the key in embedding and extraction algorithms. The cover image is processed in Red, Green, Blue (R,G,B) space to embed the watermark. The one level DWT decomposition is applied on the B (Blue) channel of cover image. The singular values of different subband coefficients of B channel are altered using wide range of scaling factors to embed the singular values of watermarks. Four watermark images are embedded into four subbands of B channel which is very difficult to remove or destroy. The combinations of DWT-SVD and Julian set patterns increases the security, robustness and imperceptibility of the watermarked image. The robustness and perceptual quality of the watermarked image is analyzed considering different types of image processing attacks.