The Research Of Text Digital Watermarking Technology

In recent years, with the development of communication technology, the digital technology which is stored in different multimedia such as text, image, audio and video has been widely used. The development of technology brings us great convenience. However, it also brings many troubles like infringement and piracy. Therefore, the problem of how to protect the copyright has become an important research topic. In the field of multimedia information security research, the digital watermarking technology develops quite quickly as a mean to protect the security of information. It can protect the copyright and data security effectively. However, compared with image, audio and video digital watermarking technologies, the text digital watermarking technology develops relatively slowly due to the limitation of text. So there are fewer research results.Most of the text digital watermarking algorithms nowadays have the limitations of capacity and robustness. This paper analyzes the characteristics of Chinese characters and researches many text digital watermarking algorithms. The paper proposes two algorithms-the text digital watermarking algorithm based on the number of characters’ connected domains and the its advanced algorithm. In the algorithms proposed in this paper, a character can be embedded watermark by changing its connected domain number. And the number of connected domain corresponds to specific watermark information. The algorithms make use of the technology of document image to extract the watermark embedded in the text. This paper makes experiments to test the performances of the algorithms by embedding watermark and extracting watermark. And it also tests the robustness of the algorithms presented. The experimental results show that both of the two algorithms improve the capacity effectively and have better robustness and imperceptibility.