Some Novel Information Hiding Technologies Based On A New Class Of Orthogonal Function Systems

Information hiding is an interdisciplinary subject related with many science fields, such as perception science, information theory, cryptography and other sciences. There are many kinds of classification methods to information hiding. According to the transformation domain, we have the space domain method and the frequency domain method. The familiar frequency domain method includes discrete cosine transform, discrete wave transform, discrete Fourier transform and so on. The frequency domain method has many advantages compare with space domain method, such as that the embedded information energy can be distributed into every pixel of the space domain; some concealing character of human apperceive system can expediently combined with encoding course; it is compatible with data compression standard such as JPEG; usually it has good robustness. The traditional frequency domain method always utilizes the orthogonal function systems such as Fourier trigonometric function system, polynomial orthogonal system, Walsh function and Haar function. Orthogonal function systems can be applied into many fields, such as signal dispose, engineering computation, frequency analysis, regression analysis, distant measure technology, information technology and graphic and image processing.In this paper we focus on a new class of orthogonal function systems—U systems and V systems. Both of there systems are composed by a series of piecewise polynomials of degree k, those kinds of complete orthogonal function systems have character of not only smooth orthogonal functions but also discontinuous orthogonal functions. These unique characters can be used in information hiding and digital watermarking. There are two contributions in this thesis as follows:1. People pay more and more attention to the anti counterfeit technology of commercial bill. By combining the digital watermarking technology, we propose in this paper a novel digital watermarking method of commercial bills for anti counterfeit based on a new class of orthogonal function system. This method has some characteristics to the anti counterfeit of commercial bills: (1) The method is very easy to realize, has low cost and high income. (2) The speed of carrying out is quick, it can quickly embed and extract watermark. (3) The method has high robustness, can resist some attacks such as damage,cutting,compression of JPEG, adding noise to a certain degree. (4) The application domain is wide, the method adapt to all type of bill: bank check,bankbook,bond,invoice,tax,welfare lottery ticket of government, shopping ticket,enterprise negotiable securities,stock,vehicle passage ticket, airplane ticket, gate ticket and other bills.2. The digital watermarking technology is an important branch of information hiding, it is an availability method to realize multimedia copyright protection and information integrality, and it is also a research hot spot in information field. However majorities of watermark technology are concentrated in digital image, audio, electronic book, video and other digital production. Less attention has been paid on the research of graphic digital watermarking. Actually the copyright protection of graphic data is also vey important problem in the security of multimedia information. Based on V descriptors a new method of graphic watermarking is presented in this paper. This algorithm has high robustness. It can resist some common manipulations, such as rotation, translation, scaling and local modification.