Research On Zero-Watermarking Algorithms Based On SVD Or Fourier-Mellin Transform

Data hiding is an important branch of information security theory, in which digital watermarking is a hot research direction. Digital watermarking will play an important role in the area of digital work copyright protection. Theory of traditional robust digital watermarking in images is introduced firstly, and then the concept and algorithms of zero watermarking are studied mainly. The conflict between invisibility and robustness is avoidless in traditional watermarking, but solution can be given by zero watermarking . Zero watermarking algorithms based on SVD and FMT (Fourier-Mellin transform) are designed in this paper. The good performance of the two algorithms is verified by some common image processing and attack experiments.Zero watermarking algorithms based on SVD extracts max singular value by SVD of blocked image as image feature to construct zero watermarking. The experimental results show that not only conflict of invisibility and robustness is avoided, but also the algorithm is more robust against some commonly image attack than traditional watermarking algorithm based on SVD. Zero watermarking algorithms based on FMT constructs zero watermarking with the factor of FMT. The experimental results show that the algorithm expands capacity of watermarking while enhances the resistance against geometric attack.Zero watermarking needs a registration system to realize copyright protection. It is a new direction of digital watermarking, and the research of algorithm and the establishment of registration system still need to be improved. Nevertheless the character that it doesn't modify original data provides a new method for the application of digital watermarking.