Watermarking For Word And Adobe Acrobat Documents

As the primary information carrier, digital text is more used by human than video andaudio. Like piracy for printed books, there are copyright protection and copyrightauthentication problems for electronic carriers.This thesis proposes watermarking algorithms respectively apply to Word and AdobePDF documents:The Image-Plus-TrueType algorithm applies to Word document. In the embed algorithm,reading the image into a “0-1” matrix and creating new characters “0” and “1” by TrueType.Embed the two new characters into the original document in the matrix order. Hide the newcharacters by the “hidden” function of Office Word and the display properties of TrueTypefont library. The extract algorithm is the reverse of embed algorithm.The Image-Plus-Acrobat algorithm apply to PDF document was also proposed. In theembed algorithm, embed the matrix into a PDF document like the primary algorithm. Thenuse the “fill” and “character spacing” functions of Touchup tool of Acrobat to hide the newcharacters. The extract algorithm is the reverse of embed algorithm.The feasibility of the two algorithm was verified, and the algorithm apply to OfficeWord2003was implemented by C++language and Visual Studio2008platform.The simulation results show that both the Image-Plus-TrueType and theImage-Plus-Acrobat algorithm have great robustness, transparency and security; they canlocate the tampered location and compact to variety of language; they can effectively protectthe copyright of the textual documents and authenticate the copyright. However, theImage-Plus-TrueType algorithm was limited by the watermark image size; theImage-Plus-Acrobat algorithm’s robustness and feasibility need improvement.