A blind dual color images watermarking based on IWT and sub-sampling

Abstract

With more color images being widely used in the Internet, embedding color watermark image into color host image is one of the most challenging issues in robust image watermarking, it is usually termed as dual color image watermarking. Based on integer wavelet transform (IWT) and sub-sampling, this paper proposes a blind dual color image watermarking scheme, which is different from some existing works using the binary or gray-level image as watermark. Firstly, the color host image is subsampled into four sub-images and each sub-image is transformed via IWT to obtain four LL sub-bands, we can find that there is a strong correlation between the LL sub-bands coefficients, this property can be explored for embedding and extracting watermark in a blind way. Experimental results, show that the proposed color image scheme has stronger robustness against most common attacks such as image compression, cropping, noising and scaling etc