Research On Text Carrier Information Hiding And Related Technology

With the further development and application for information technique, information security has been absorbing much more attention by every country in the world. Information hiding has become a hot interest area in the research of information security, which has wide applications in many fields such as copyright protection of digital media, hidden communication. Steganography and watermarking are two main sub-disciplines of information hiding. Steganography is the art and science of communicating in a way which hides the existence of the communication.The carriers of information hiding mainly include image, video, text, audio and so on. Text carrier is acting as a more and more important role in people's work and life, which is a very important carrier type in the information hiding. The property right protection and content validation of text carrier have been considered significant by people. Detailed researches and practice are completed in this paper on text carrier information hiding, steganalysis and other correlated techniques. The main works and creations are as follows:1. The conception and category of text carrier is explainded. The research direction of text carrier information hiding is oriented . The structure, redundancy and hiding security for text carrier are analyzed in theory, and the theoretical base of text carrier is founded.2. Some normal text carriers such as TXT, WORD, PDF, and other text carriers based on Web application for information hiding such as HTML, XML. CSS and XSL are summarized and analyzed. The structure and redundancy characteristics are deeply anatomized for those documents.3. A new information hiding algorithm based on font zooming for WORD is proposed. The algorithm coding for the scaling of WORD font, could embed 3 bits in each character. The algorithm increases the security from chaos sequence encryption for secret message. We made analysis comparison to the two ways of achieving information hiding for WORD, such as VBA and Office Automation technique for VC, by the side of time cost, difficulty extent etc.4. We take the information hiding for text carrier based on Web application as an important research content. A CSS(Cascading Style Sheet) information hiding algorithm based on color name is proposed, using the different compiling methods of describing RGB color for CSS document. A new CSS information hiding algorithm based on rule structure is proposed, according to CSS document structure and rule compiling mode. Some definitions about CSS equivalence rule are founded, some corresponding theorems and deductions are deduced on the basis of mathematics model, thus the embedding and extracting arithmetics are worked out, and the experimental results indicate this information hiding algorithm has quite large embedding capacity and security. A type of information hiding algorithm based on XML query rewriting is proposed, according to the structure characteristic of XML document and the XML translating method characteristic by XSL. The path query automaton is founded, and we constitute the rules between embedding message and query rewriting to achieve information hiding by modifying path query results for XML.5. A new information hiding algorithm based on partitioned for binary text image is proposed, on the basis of analyzing the virtues and questions of two representational embedding algorithm for binary text image in detail. The algorithm partition image into blocks firstly, then calculate the characteristic value for each image blocks, and choose fine vision image blocks as embedding blocks. The embedding method adopt a great capacity embedding method, utilizing pixel flippability criterion to determine the best flipping pixel where have several pixel flipping lacations to choose. The experimental results indicate this algorithm could not only increase capacity in each image block, but also preserve fine vision effect.6. Some beneficial explores are done about steganalysis for binary text image, a steganalysis algorithm based on pattern analysis for binary text images is proposed on the bases of analyzing existent research achievements. The"pattern"conception for binary image is put forward in the algorithm, and classify the patterns into three categories according to human vision extent, thus establish an embedding location pattern storeroom. The steganalysis algorithm based on pattern analysis is proposed based on statistic analyzing the changing characteristics of the patterns for binary text images before and after embedding messages. The experimental results indicate this algorithm is a fine detection algorithm.Finally, we summarize our research work, and indicate the research directions of information hiding and correlated techniques for text carrier.