New normalized fractal watermarking scheme based on pseudo-Zernike moments
基于伪Zernike的归一化分形水印算法研究

This paper proposed a new image watermarking scheme robust to geometric attacks.Firstly, extracted significant region by using normalization and invariant centroid theory.Then, divided significant region into two groups:self-similarity and non-self-similarity blocks by fractal coding and pre-set threshold, picked up the robustest pseudo-Zernike moments among the pseudo-Zernike moments of the self-similarity blocks.Finally, embedded the watermark by quantizing the magnitudes of the robustest pseudo-Zernike moments. Experimental results show that the scheme is not only invisible and robust against common signals processing such as median filtering,sharpening ,noise adding, JPEG compression,etc, but also robust against the geometric attacks such as affine transform,local geometric distortion, etc.