Cryptology ePrint Archive: Report 2005/120

On Designatedly Verified (Non-interactive) Watermarking Schemes

Malapati Raja Sekhar and Takeshi Okamoto and Eiji Okamato

Abstract: Although many watermarking schemes consider the case of universal verifiability, it is undesirable in some applications. Designated verification is a possible solution for this problem. Watermarking scheme with (non-interactive) designated verification through non-invertible schemes was proposed by Lee et al in 2003, to resolve multiple watermarking problem. Yoo et al [14] proposed a very similar watermarking scheme. In this paper, we propose a cryptanalytic attack on both of these schemes that allows a dishonest watermarker to send illegal watermarked images and to convince the designated verifier or customer that received watermarked images are valid. We modify the above schemes to overcome the attack. Further, we also propose a new robust watermarking scheme with (non-interactive) designated verification through non-invertible watermarks. Interestingly, our scheme can be extended for joint copyright protection (security of ownership rights for images to be owned by more than one entity).

Category / Keywords: applications / watermarking, designatedly verifiable watermarks, oblivious decision proofs, equality of discrete log proofs

Date: received 16 Apr 2005, last revised 17 Aug 2005

Contact author: malapati_r at isical ac in

Available formats: PDF | BibTeX Citation

Note: Some typos are corrected.

Version: 20050817:113216 (All versions of this report)

Discussion forum: Show discussion | Start new discussion