Text watermarking by syntactic analysis
Miyoung Kim · Annual Conference on Computers · 2008
This paper explores the method of text watermarking for Korean by syntactic analysis. The proposed method is useful for agglutinative languages - such as Korean, Turkish, etc.-- of which syntactic constituent order is relatively free. Our proposed natural language watermarking method consists of several steps. First, we construct a syntactic dependency tree of input text. Next, we choose target syntactic constituents to move. Then, we embed watermark bits. If the watermark bit does not coincide with the movement bit of the target constituent, we move the syntactic constituent in the syntactic tree. Finally, from the modified syntactic tree, we obtain a marked text. From the experimental results, we show that the coverage of our method is 75%, which outperforms that of previous systems, and the rate of unnatural sentences of marked text is better than that of previous systems. Even if the information-hiding capacity is worse than that of the previous systems, our marked text keeps the same style, and it also has the same information without semantic distortion.