Compris provides a way of inserting a digital watermark into text using a product called TextMark.
This method for digital watermarking of information is very difficult to remove because an attacker would also need to model the complete language correctly in a computer.
Text processing becomes increasingly simple; writing good texts remains difficult. With TextMark you have the ability to protect your intellectual property. This innovation distinguishes itself by its broad applicability to all kinds of textual documents and its tamperproof characteristic.
The problem that led to the creation of TextMark was how to embed a watermark into a text-based format. A common method changes the word distances slightly and operates with similar concepts as watermarking tools for images. Unfortunately, it is extremely simple to remove such a watermark in images and text completely. Currently existing pirate tools enable any school boy to remove such watermarks. The text, the image, or the song by itself will still remain, allowing the work to be copied and resold, or to be published unauthorized on another Web site. In such cases, chances of proving authorship are slim.
The solution was to directly integrate the digital watermark into the text using a rephrasing technique. The text rephrasing is minimal, which means only a slight change in the choice of synonyms, word order, positions of additional blanks for block justification, etc. The meaning of the text will be retained fully because the program is able to understand language. Sections that cannot be completely understood remain unchanged. The watermark can be hidden as often as possible in the text.
TextHide was designed with one goal in mind: Create the most secure and most inconspicuous method for transmitting and storing information. To add to this, TextHide uses the best-known encryption methods and additionally the encrypted information is hidden so that it cannot be recognized as such. Everyone is able to decode something from the text, but if the text was previously encrypted, it cannot be determined that the decoded data is relevant. Because it is not obvious whether the data present is encrypted, no direct decryption attack can happen. When using obviously encrypted data, an eavesdropper will try to find the kind of encryption method to specifically crack this method.
To solve this problem, TextHide uses the best encryption method and hides the data in texts. The attacker will believe he is reading unencrypted text. Even when encrypted data is suspected, the encryption method used is still unknown. The TextHide method is also able to decode secret data from any kind of text. The decoded data will only make sense when meaningful data has been previously hidden in the text. An attacker is not able to distinguish encrypted data from meaningless data.
More information can be found at www.compris.com.