The text image watermarking using arnold scrambling and DFT

Fan Wu, Jingbing Li

College of Information Science and TechnologyHainan University,Haikou, China

With the popularization of Internet and the development at full speed of the multi-media technology, the copyright protection of digital works has already become the hot issue at present. Generally speaking, image, audio and video watermarking is comparatively similar in algorithm realization, with their redundancy, in which we can embed watermark. But other than the aforementioned, there is no redundancy to transfer secret info in text document. Nowadays, to embed watermark in text documents are limited to methods such as shifting the line and word, amending the characters' traits and disposing in the level of semantics. All these algorithms are not robust or lack of concealment, generally not serving the turn of Chinese text documents riffles. Based on the studies of the document digital watermarking methods and techniques, this dissertation presents that the problems of existed documents watermarking algorithms can be solved by Arnold Scrambling and DFT technique. The experimental results show that the scheme has strong robustness against common attacks and geometric attacks.