Crypto-SVD based robust and protected digital image watermarking in discrete wavelet transform domain

Abstract

With increase in image based applications, the necessity of providing security for the image data increases. Watermarking provides one of the best solution to overcome this issue. This paper presents the Crypto-SVD based robust image watermarking in Discrete wavelet transform (DWT) domain, in which the combination of cryptography and singular value decomposition (SVD) is applied in the DWT domain. The DWT is applied to the grayscale host image, which divides the image into low frequency (LL subband) and high frequency (HH, HL and LH subbands). The SVD is applied to HH subband and then encrypted watermark is embedded in the singular matrix of the SVD. In the proposed scheme the encrypted watermark is embedded in the host image. After encryption it is very difficult to predict the encrypted watermark, which saves the watermark from getting modified or destroyed. With various attacks i.e. image processing attacks, geometrical attacks, etc. the watermark is compared with the original watermark after extraction. The experimental results validate the robustness feature of the proposed scheme.