A new robust color image watermarking using local quaternion exponent moments

Desynchronization attacks that cause displacement between embedding and detection are usually difficult for watermark to survive. It is a challenging work to design a robust image watermarking scheme against desynchronization attacks, especially for color host images. In this paper, we propose a robust color image watermarking scheme based on local quaternion exponent moments. The proposed scheme has the following advantages: (1) the stable and uniform color image feature points are extracted by the new color image detector, in which the probability density gradient and color invariance model are used, (2) the affine invariant local feature regions are constructed adaptively according to the variation of local probability density and (3) the effective quaternion exponent moments are derived and introduced to embed watermark in the color image, which consider the correlation between different color channels. Experiments are carried out on a color image set of 100 images collected from Internet, and the preliminary results show that the proposed color image watermarking is not only invisible and robust against common image processing operations such as sharpening, noise adding, and JPEG compression, but also robust against the desynchronization attacks.