Research On Zero Watermarking Algorithm Based On Wavelet Moment

With the rapid development of digital communication network and multimedia technology, more and more multimedia products have been issued through network, which have made the issuance and transfer of information become more convenient. But as digital products can be easily copied and interpolated illegally, anybody can copy and issue the product which is protected by the intellectual property rights. The copyright protection of digital products has been seriously threatened. Digital watermarking is an effective way of copyright protection and content certification, so it has became a research hotspot in the field of multimedia information security. Zero watermarking is a new type of digital watermarking technology. The difference between general digital watermarking and it lies in that it uses the features of the original image to construct the watermark rather than directly embedding a watermark in the image. So it does not break the original image. Moreover, it works with a third-party trust institution to do the role of copyright protection.Wavelet analysis, because of its good time-frequency localization properties, has become an effective tool in signal processing and image analysis system. Moment invariants, because of its non-geometric transformation invariance, has widely used in pattern recognition, position estimation, computer vision and image reconstruction. Wavelet moment is a combination of wavelet analysis and moment invariant. By uniting the respective advantages of wavelet analysis and moment invariants, it accomplishes a very good application value.The research work presents a zero watermarking algorithm based on wavelet moment by focusing on wavelet moment and zero watermarking technology. The main research work including:①First of all, the paper sets forth digital watermarking technology thoroughly. Through presenting the basic concept, models, characteristics, classification, evaluation methods and attack devices of digital watermarking, the paper leads an introduction of the two types of common digital watermarking algorithms and security digital watermarking systems.②The paper studies the moment function of the images. Essentially, different moment functions are made up of various kernel polynomials that are continuous or discrete. First in this paper, the Hu moment, Legendre moment, Zernike moment, Complex moment, Chebyshev moment and wavelet transform theory are introduced. Then the research introduces the concepts, principles of wavelet moment and proves the rotation, scaling and translation invariance for wavelet moment. Finally, the research makes a comparison between Hu moment, Zernike moment and wavelet moment from a experimental point of view.③This paper makes a thorough research over zero watermarking technology. The concept of zero watermark, characteristics and advantages are introduced. In this paper, the zero watermark algorithms has been classified from the point of view of watermarking content, based on the study of existing zero watermark.④In the last part of this paper, the researcher makes use of the excellent properties of wavelet moment to propose a digital watermarking algorithm based on wavelet moment. And the research also gives a concrete realization of the process and the experimental results of the algorithm. Experiments show that the algorithm has a good robustness for common geometric attacks, compression, noise attacks and other attacks. Finally, the researcher compares algorithm with other previous algorithms.