A wavelet-based watermarking algorithm for digital image protection

A wavelet-based watermarking algorithm is proposed in this paper. By using J M Shapiro's view [2] about zero-tree, we embed four watermarks “reversed” to each other in different levels of the zero-tree. During the embedding of the watermarks, the Human Visual Model (HVM) is introduced to maximize the hiding capacity. Due to HVM and the characteristic of “reverse” of the four watermarks, although the magnitude of the data which are embedded in the host image is large, we can't feel any distortion of the watermarked image. Moreover, we develop a new complementary detecting technology, using which five watermarks are detected in the process of detecting; they may complement each other to reduce the detecting error. The experimental results show that this method can resist various attacks.