This paper explores the morphosyntactic tools for text watermarking and develops a syntax-based natural language watermarking scheme. Turkish, an agglutinative language, provides a good ground for the syntax-based natural language watermarking with its relatively free word order possibilities and rich repertoire of morphosyntactic structures. The unmarked text is first transformed into a syntactic tree diagram in which the syntactic hierarchies and the functional dependencies are coded. The watermarking software then operates on the sentences in syntax tree format and executes binary changes under control of Wordnet to avoid semantic drops. The key-controlled randomization of morphosyntactic tool order and the insertion of void watermark provide a certain level of security. The embedding capacity is calculated statistically, and the imperceptibility is measured using edit hit counts.

Date Published: 2 March 2007
PDF: 12 pages
Proc. SPIE 6505, Security, Steganography, and Watermarking of Multimedia Contents IX, 65050X (2 March 2007); doi: 10.1117/12.708111

Published in SPIE Proceedings Vol. 6505:
Security, Steganography, and Watermarking of Multimedia Contents IX
Edward J. Delp III; Ping Wah Wong, Editor(s)