An English Text Digital Watermarking Algorithm Based On The Idea Of Virus Debris

It becomes more and more attractive to protect copyrights by text digital watermarking. Because of the inherent issue ("two values 0 or 1"), there are not rich textures in a digital text. The difficulties to solute the problem of robustness and the valid loading are increased largely. As a result, the researches of text digital watermarking fall behind other digital media largely. The feature coding method made by N ? F Maxemchuk solves the loading problem satisfactorily. However, the robustness problem is not solved ideally. Most of the existing text digital watermarking algorithms are based formats (files formats, such as: DOC, PDF, etc., typesetting formats, such as: the style, the size, the color of the words and the character spacing and line spacing, etc.). The watermarking information embedded in the digital text will be extracted no more, if the formats of a text are changed. It is a common lack that the robustness of most text digital watermarking algorithms is not strong. The maturity and development of text digital watermarking technology are constrained seriously just because of the robustness.This paper presents a novel English text digital watermarking algorithm based on the idea of computer virus. The basic idea of location of the algorithm comes from computer viruses. The specific is: dividing the whole characters of an English text with some specific alphabets into several short paragraphs (elements). These elements are then sorted into several aggregates by specific rules, and then one bit watermarking information is embedded into an aggregate. The basic ideal of the embedding method of the algorithm comes from Unicode code. There are some characters which share the same shapes but are stored in computers by different codes. The watermarking information piece embedded into an aggregate can be extracted well as long as only one elements of the aggregate which carried a bit watermarking information are not destroyed. The algorithm can be done in pure text TXT; attacks based on formats are invalid. Thereupon, the robustness performance of the algorithm has been well ensured theoretically. Actually, the splendid performance in robustness of the algorithm is proved by experiments.A software system based on the proposed algorithm is developed in .NET + MS Access environment. It is proved by extensive experiments that the robustness of the algorithm will be able to achieve the desired effect theoretically. The algorithm can be done in pure TXT text, but also can be achieved in the formatted documents off cause. It can be widely used in various electronic publications in English.