A zero text watermarking algorithm based on non-vowel ASCII characters

The widespread use of Internet and other communication technologies has bring along the ease to reproduce, disclose, and distribute digital content. In addition to getting the benefits of information exchange, the digital community is confronted with authentication, forgery, and copyright protection issues. The amount of textual information on Internet is increasing besides images, audios, and videos. Therefore, copyright protection of plain text is the most important issue. In this paper, we propose a zero text watermarking algorithm based on occurrence frequency of non-vowel ASCII characters and words for copyright protection of plain text documents. The embedding algorithm incorporates occurrences of non-vowel ASCII characters in text partitions to form a key based on the watermark. The extraction algorithm extracts the watermark from the noisy text to identify original copyright owner. Experimental results prove the effectiveness of the proposed algorithm on text encountering dispersed insertion and deletion attacks occurring randomly.