A ROBUST NON-BLIND HYBRID COLOR IMAGE WATERMARKING WITH ARNOLD TRANSFORM

Abstract

Due to development of the internet technologies and other services, requirement of rightful ownership and copyright is highly required. Hence to protect the copyrighted data from unauthorized user, a robust non-blind hybrid color image watermarking scheme is presented. In this proposed scheme, we use color watermark instead of gray watermark which is generally used in most of the existing digital image watermarking techniques. YCbCr color space used to separate the R, G and B channel of images. Y channel of color watermark is embedded into corresponding Y channel of cover image using proposed scheme. Arnold transform are used to scramble the watermark image before embedding process in order to provide more security. The singular value of bands is going to embed with singular values of watermark by making use of variable scaling factor (α). As original image is required at the time of extraction of watermark hence propose scheme belong to non-blind technique group. The two-fidelity parameter namely Peak signal to noise ratio (PSNR) and structural similarity (SSIM) index are used to measure the imperceptibility whereas similarity between original and extracted watermark is measured by using normalized correlation coefficient (NCC). We also compared the results of proposed scheme with other existing watermarking schemes. The experimental results prove effectiveness of the proposed image watermarking scheme in term of robustness and imperceptibility.