An Enhanced Watermarking Scheme in DWTSVD-FWHT Domain Using Key Based Encryption

Robustness, imperceptibility and high embedding capacity have been main concerns of researchers in development of new techniques in field of Digital Image Watermarking. Since embedding capacity and imperceptibility of Watermarked Image are contrary to each other, so it becomes tedious to achieve both. Here, in this paper we proposed an enhanced watermarking scheme in discrete wavelet transformation - fast walsh hadamard transform - singular value decomposition (DWT-FWHT-SVD) domain with high embedding capacity and good Imperceptibility shown by experimental results. As far as matter of robustness and security is concerned, watermark is being Encrypted using a key based algorithm to add another security layer. Gray scale cover Images (10241024 size) are used for embedding four gray scale watermarks (256256 size) into single cover image. Peak Signal to Noise Ratio (PSNR) and the Normalized Correlation (NC) are parameters used to scrutinize the performance of given technique. To measure the robustness we calculated NC and we also subjected this technique to different attacks to show its robustness against attacks.