Visual Cryptography for Image Processing and Security: Theory, Methods, and Applications

Preface
Acknowledgments
Contents
About the Authors
Acronyms
1 Introduction
	1.1 Introduction
	1.2 Access Structure
	1.3 Fundamental (k, n)-VCS
	1.4 Equivalence of VCS Definitions
		1.4.1 The Equivalence of Two Definitions of Threshold Basis Matrix VCS
		1.4.2 The Equivalence of Two Definitions of General Access Structure Basis Matrix VCS
		1.4.3 The Equivalence of Two Definitions of General Access Structure SIVCS
		1.4.4 The Inequivalence of Two Definitions of Non-basis Matrix VCS
	1.5 Step Construction of VCS
		1.5.1 Definition of Step Construction and Step Construction of (n, n)-VCS
		1.5.2 Simplifying the Access Structure by Using Equivalent Participants
		1.5.3 Step Construction of VCS for Access Structure  Γm = {A1,A2,ƒ, Ar} such that A1A2 @汥瑀瑯步渠Ar = {a1, a2,ƒ, ar}neq
		1.5.4 Step Construction of VCS for General Access Structure
	1.6 Exercises
	References
2 Various Problems in Visual Cryptography
	2.1 Alignment Problems
		2.1.1 Precise Alignment of VCS
		2.1.2 Visual Alignment of VCS
	2.2 Flipping Issues in VCS
		2.2.1 Share Generating
		2.2.2 Share Expansion
	2.3 Distortion Problems
		2.3.1 The Fountain Algorithm
		2.3.2 Improving VC Quality
	2.4 Thin Line Problems (TLP)
	2.5 Exercises
	References
3 Cheating Prevention of Visual  Cryptography
	3.1 Definitions
	3.2 Attacks
		3.2.1 Attack on Horng\'s CIVCS
		3.2.2 Detectable Attacks
		3.2.3 Collaborating Cheaters
		3.2.4 Cheater Colluding
		3.2.5 New CIVCS
	3.3 2D Barcode Authentication for Basic VC Shares
		3.3.1 Barcode
		3.3.2 Barcode Embedding for Authentication of VC Shares
		3.3.3 VC Authentication Using 2D Barcodes
		3.3.4 Secret Revealing
	3.4 Braille for Authentication of Basic VC Shares
		3.4.1 Braille
		3.4.2 Braille Embedding in VC Shares
	3.5 Exercises
	References
4 Various Visual Cryptography Schemes
	4.1 Embedded Extended VCS
		4.1.1 Introduction
		4.1.2 Embedded EVCS
		4.1.3 Generating the Covering Shares for an Access Structure Using the Dithering Matrices
		4.1.4 Embedding the Shares of the Corresponding VCS  into the Covering Shares
		4.1.5 Further Improvements on the Visual Quality of Shares
	4.2 Probabilistic Visual Cryptography Scheme (PVCS)
	4.3 Size-Invariant VCS (SIVCS)
	4.4 A ME-SIVCS that Satisfies ME-SIVCS-2 Security
	4.5 A ME-SIVCS that Satisfies ME-SIVCS-1 Security
	4.6 Threshold VCS (TVCS)
		4.6.1 Definitions of TVCS
		4.6.2 Basis Matrix
	4.7 Construction of (k, n)-TVCS
	4.8 Concolorous TVCS
		4.8.1 The Model of Concolorous TVCS
		4.8.2 The Existence and Construction of Concolorous TVCS
	4.9 Construction of (k, n)-TEVCS
		4.9.1 The Model
		4.9.2 Constructions of (k, n)-TEVCS
	4.10 A Security-Enriched VCS
		4.10.1 PSSS
		4.10.2 ESSVCS
	4.11 Exercises
	References
5 Various Color Schemes of Visual Cryptography
	5.1 Introduction
	5.2 Basic Principles of Color Models
	5.3 Color VCS and Color EVCS in the Traditional Visual Cryptography Model
	5.4 Exercises
	References
6 Various Applications of Visual Cryptography
	6.1 Watermarking Applications
		6.1.1 Watermarking
		6.1.2 Visual Cryptography
	6.2 Resolution Variant Visual Cryptography
		6.2.1 License Plate Embedding
		6.2.2 Multiresolution VC Scheme
	6.3 Exercises
	References
Glossary
Index