Skip Navigation


The Computer Journal Advance Access originally published online on January 29, 2008
The Computer Journal 2008 51(6):710-722; doi:10.1093/comjnl/bxm118
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
51/6/710    most recent
bxm118v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Yang, C.-N.
Right arrow Articles by Chen, T.-S.
Right arrow Search for Related Content
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2008. Published by Oxford University Press on behalf of The British Computer Society. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

Visual Cryptography Schemes with Reversing

Ching-Nung Yang*, Chung-Chun Wang and Tse-Shih Chen

Department of Computer Science and Information Engineering, National Dong Hwa University, No. 1, Section 2, Da Hsueh Road, Hualien, Taiwan

* Corresponding author: cnyang{at}mail.ndhu.edu.tw

Received 7 May 2008; revised 15 December 2008

The Visual cryptography scheme (VCS) is a perfect secure method that encrypts a secret image by breaking it into shadow images. A distinctive property of VCS is that one can visually, without computation, decode the secret by superimposing shadow images. However, much of the contrast of the reconstructed image is lost. A different kind of VCS has been recently proposed by Viet and Kurosawa, called VCS with reversing, allowing participants to perform a reversing operation (reverse black and white) on shadow images. Two drawbacks of the Viet–Kurosawa VCS are: (1) one can only reconstruct an almost ideal contrast image but not an ideal contrast image and (2) the Viet–Kurosawa VCS is constructed just from a perfect black VCS. This paper shows a real perfect contrast VCS such that the black and white pixels are perfectly reconstructed within finite runs, no matter what VCS (perfect black or non-perfect black) is used.

Key Words: visual cryptography scheme • shadow image • ideal contrast


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.