A Geometric Robust Watermarking Algorithm Based on DWT-DCT and Zernike Moments

This paper proposed a novel multibits watermarking algorithm providing robustness against geometric attacks. The robustness is achieved from three aspects: ① Choosing the in- scribed disk of the host image as the Zernike moments computa- tion domain and the square in the disk as the watermarking em- bedding domain. ② Embedding the watermark in the cascade discrete wavelet transform-discrete cosine transform (DWT-DCT) domain by modulating the specified coefficient pair in each sub block. ③ Saving two selected Zernike moments of the original watermarked image to estimate and correct the geometric attacks before watermark extraction. Experimental results show that the proposed algorithm is robust to any angle of rotation attacks and wide range of scaling attacks, and as well, a variety of other attacks such as lossy compression, common signal processing.