Geometrically Invariant Color Image Watermarking Using Mean-Based 2D Color Histogram

Watermark resistance to geometric attacks is a crucial issue in watermark system design. Challenging cropping and recently reported random bending attacks (RBAs) are still the Achilles heel for most of the existing watermarking schemes. This paper presents a geometric attacks resistant zero-watermarking scheme for color images, which is based on one of the image geometric invariant representations-the mean-based 2D color histogram extracted from two different color components by reference to the mean value of the effective pixels of each component. Experimental results demonstrate that the proposed method provides a satisfactory performance for various geometric attacks and common image processing operations, including affine transformations, cropping, RBAs, additive noise, filtering, JPEG compression, etc.