Geometric invariant blind image watermarking by invariant Tchebichef moments.

Many proposed image watermarking techniques are sensitive to geometric distortions, such as rotation, scaling and translation. Geometric distortions, even by slight amount, can make watermark decoder disable. In this paper, a geometric invariant blind image watermarking is designed by utilizing the invariant Tchebichef moments. The detailed construction of invariant Tchebichef moments is described. Watermark is generated independent to the original image and is inserted into the perceptually significant invariant Tchebichef moments of original image. The watermark decoder extracts watermark blindly utilizes Independent Component Analysis (ICA). The computational aspects of the proposed watermarking are also discussed in detail. Experimental results have demonstrated that the proposed watermarking technique is robust against geometric distortions and other attacks performed by popular watermark benchmark-Stirmark, such as filtering, image compression, additive noise, random geometric distortions.