ABSTRACT
The watermarking techniques are divided with respect to host data, robustness, perceptual quality and watermark extraction. This chapter provides applications of some document watermarking schemes for Indian language text. It presents the state-of-the-art document watermarking techniques. The existing document watermarking schemes are designed based on: images, contents, structures, and zero-watermarking. The document watermarking is a difficult task as it is very sensitive and has less watermark capacity. The document file is treated as an image in image based approach. The line-shifting scheme changes the text information in the document image by exchanging text sentences upward or downward according to the watermark bits. Structure based approach is used for document watermarking. In this approach, the text structure is used to embed the watermark data. The original text in documents can be modified by advanced techniques on the computer so that researchers can develop new watermarking approaches with higher imperceptibility capacity.
