Research And Application Based On Information Hiding Algorithm

With dramatic advance of Internet and wide application of the multimedia technology, information-hiding techniques have become a new hot topic in the domain of the information security. Today's information hiding techniques mainly use image,audio and video as cover objects. In the thesis, firstly we introduce the basic concepts and theoretics of information hiding technologies and digital watermarking, such as charachteristics, classification and application and so on, then the information hiding techniques based on text and on image are discussed in detail in this paper.(1) Improvement on information hiding algorithms based on textWe analyze the information hiding techniques based on text in detail and give a survey of today's polular algorithms of text document information hiding and their advantages and shortcomings. In this algorithm the text characters are firstly determined by punctuations, and then by XOR the encrypted charcters and the encrypted watermarking information, the watermark is embedded into the text. The experimental results show that the algorithm has complete hiding effectiveness and strong robustness. However, the method can only be applied to information hiding, not be used for copyright protection, yet to be improved.(2) Improvement on information hiding algorithms based on imageA digital watermark embedding algorithms in transform domain is presented, which is based on analysis and research of DCT, DWT and Neural Network. With the coefficients after Discrete Cosine Transform(DWT) of the digital image having correlations, we firstly consider making another Discrete Cosine Transform(DCT) of them, and then embedding digital watermark. The algorithm has the characteristics of both DWT and DCT, so enhances the robustness. Finally, in order to verify the impercettibility and robustness of the algorithms proplsed in this paper, a lot of experiments have been done. The experimental results show that the algorithms has good imperceptibility and very strong ability against geometry attack and common image processing operations. At last a conclusion and prospect of this paper have been done.