Title: Design and implementation of a block-based lossless watermarking scheme

Authors: Fawzy Ibrahim, M. Zaki

Addresses: Department of Computer Engineering, Al-Azhar University, Cairo, Egypt. ' Department of Computer Engineering, Al-Azhar University, Cairo, Egypt

Abstract: High capacity reversible watermarking method based on block difference expansion is presented. The proposed scheme relies upon redundancy analysis for image authentication and tamper localisation. The performance of such scheme is compared with that of Tian. While Tian|s algorithm is a pixel-based embedding scheme, the proposed method is a block-based embedding technique. Thus, it can be used with the following advantages: (1) possibility of providing more capacity for authentication data (2) no compression is needed (as in case of Tian|s scheme) and (3) low time cost because of its reasonable complexity. To find out the embedding capacity both information and redundancy are examined for the underlying image. In addition a corresponding difference image is defined, its histogram is determined and its entropy and redundancy are computed. The proposed scheme creates an extra space for the authentication payload by making use of block difference expansion.

Keywords: reversible watermarking; lossless watermarking; block difference expansion; entropy; local redundancy; electronic security; authentication.

DOI: 10.1504/IJESDF.2010.033784

International Journal of Electronic Security and Digital Forensics, 2010 Vol.3 No.2, pp.164 - 185

Received: 25 Jul 2009
Accepted: 09 Jan 2010
Published online: 30 Jun 2010 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article