Proceedings ArticleDOI
Halftone visual cryptography
Zhi Zhou,Gonzalo R. Arce,G. Di Crescenzo +2 more
- Vol. 1, pp 521-524
TLDR
Halftone visual cryptography is proposed, where all shares are halftones of grey level images carrying significant visual information, and the proposed methods utilize blue-noise dithering principles to construct halftone shares having visually pleasing attributes.Abstract:
Visual cryptography encodes a secret image SI into n shares of random patterns. If the shares are xeroxed onto transparencies, we can visually decode the secret image by superimposing a qualified subset of transparencies, but no secret information can be obtained from the superposition of a forbidden subset. Such a scheme is mathematically secure, however, it produces random patterns which have no visual meaning, raising the suspicion of data encryption. In this paper, to achieve a higher level of security, we propose halftone visual cryptography, where all shares are halftones of grey level images carrying significant visual information. The proposed methods utilize blue-noise dithering principles to construct halftone shares having visually pleasing attributes.read more
Citations
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Proceedings ArticleDOI
Visual Cryptography Based on Void-And-Cluster Halftoning Technique
TL;DR: The proposed halftone visual cryptography using threshold arrays shows great flexibility for a combination of share images in order to decode a secret image, and achieves high quality share images, high speed processing and extensibility to (k,n) the visual cryptography of three share image categories.
Journal ArticleDOI
Design of visual cryptographic methods with smoothlooking decoded images of invariant size for grey-level images
TL;DR: Two visual cryptographic methods are proposed to solve the problem of pixel expansion and to improve the visual effect of the stacked image at the same time and can satisfy the security and contrast conditions required by the VSS scheme.
Patent
Method of indentifying an individual
Julien Bringer,Hervé Chabanne +1 more
TL;DR: In this article, a method of identifying an individual in which captured images are encrypted by a transformation function and superimposed over previously recorded encrypted images is presented, where the superimposition image thus formed is used for identity verification.
Journal ArticleDOI
2D Barcodes for visual cryptography
Guangyu Wang,Feng Liu,Wei Qi Yan +2 more
TL;DR: This paper analyzes VC authentication methods using 2D barcodes and embed binary codes into VC shares for authentication purpose and proposes a scheme of embedding 2DBarcodes into given VC shares to prevent cheating.
Journal Article
Visual Cryptography for Digital Watermarking in Still Images
Gwo-Chin Tai,Long-Wen Chang +1 more
TL;DR: A novel public robust digital watermarking scheme based on visual cryptography is proposed that can be open to the public, but only the owner, who uses the private sharing image of the ownership logo, can retrieve the logo for ownership.
References
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Visual Cryptography
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Book ChapterDOI
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Moni Naor,Benny Pinkas +1 more
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Journal Article
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Moni Naor,Benny Pinkas +1 more
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Proceedings ArticleDOI
Void-and-cluster method for dither array generation
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