Abstract:
The digital representation of text, audio, image and video documents has
become very popular in the last decade. The success of digital technology is largely
due to the capabilities of efficient transmission, storage, and perfect copying.
However, especially the last feature leads to severe problems because unauthorized
copying is also simplified. One approach to combat this problem is to mark a digital
document such that a copyright can be proven or the distribution path be traced.
"Digital Watermarking" means embedding information into multimedia data
that should be imperceptible but irremovable. Thus, in contrast to copyright
information included in the header of the data streams, embedded watermarks remain
in the document even after format conversions or D/A and A/D conversions.There are
numerous applications of digital watermarking such as copyright protection, copy
protection, content authentication, transaction tracking and broadcast monitoring.
Information hiding or steganography is related to watermarking but
watermarking has the additional notion of being robust against attacks and having
concern for not only the watermark but also the cover.
In this project a watermarking algorithm has been developed and implemented
which slightly modifies inter-word spaces so that different lines across a text act as
sampling points of a sine wave. The method not only embeds a watermark but also
hides information through the watermark thus providing a robust and imperceptible
way for steganography through text images. Preliminary experiments have shown
promising results.
