Dissertation > Excellent graduate degree dissertation topics show

Research of Visual Cryptography Scheme Based on Group Structure

Author: ShiLin
Tutor: YuBin
School: PLA Information Engineering University
Course: Military Equipment
Keywords: Visual Cryptography Group Structure XOR Perfect Recovery Access Structure
CLC: TP309
Type: Master's thesis
Year: 2012
Downloads: 13
Quote: 0
Read: Download Dissertation

Abstract


Visual cryptography is one kind secret sharing technology aimed at image which takestransparency as share, and can decode concealed images just with visual system of human being.The simple characteristic of secret recovering in visual cryptography can be presented asoperator “OR”. However, the easy operator “OR” has restricted the result of secret recovering,and the fundamental reason is that the algebraic structure is semi-group constructed by “or”. Asthe increasing popularity of all kinds of intelligent equipments and high-speed image processingtechnology, it will be truth or have been truth that transparency will be replaced byelectromagnetic media as the carrier of shares in visual cryptography, which provides superiorexternal environment for group structure being adopted. Group structure not only makes secretimages recovered perfectly to be possible, but also affords theory basics for designing visualcryptography schemes in the new condition.“XOR” operator is the simplest and most typical operation which can construct groupstructure. In this dissertation, the research upon group structure of visual cryptography is carriedout based on “XOR” operator. It is proved from a view of information entropy that the idealvisual cryptography scheme (VCS) can be realized by the operation of “XOR”, and the theoremof existence is proposed, then an ideal VCS which can recover secret image perfectly is designed,which based on the lucubration on the existence of ideal VCS.As the threshold structure does not meet the theorem of existence, a loop operator has beendesigned to construct one kind of basis matrices. Furthermore, a new secret recovery process hasbeen proposed which achieves a threshold structure visual cryptography with low pixelexpansion and perfect recovered secret image without distortion. Based on this, sharingcombined and extraction algorithm has been designed by changing the sharing memory model,then one visual cryptography scheme with same size of shared copies and secret images as wellas no distortion.The storage space consumption can be quite large when participants become more in thetwo kinds of no distortion visual cryptography schemes. According to the problem, byconstructing the optimization model for visual cryptography based on group structure, aXOR-based threshold scheme is designed. In this scheme, the problem of basic matrixconstruction is translated to evaluation of probability, and the shares are generated by choosingencryption rule with probability-matrix. The scheme not only improves the contrast greatly, butalso no pixel expansion. This dissertation lays the foundation for research of perfect recovery.

Related Dissertations

  1. Research and Circuit Imp. of SRAM Soft-Error Detection and Correction,TP333.8
  2. Based on the study of all-optical logic gates for fiber nonlinear effects,TN253
  3. Finite Groups Determined by the Sum of Its Element Orders,O152.1
  4. A Study of Some Key-Techniques of PKI and It’s Application,TP393.08
  5. Paleozoic exploration potential of isolated West fault zone,P618.13
  6. Research on the Adaptability of Highway Network Structure of City Group,U412.1
  7. Two types of secret sharing scheme,TN918.1
  8. Some Cryptographic Applications of Hyperelliptic Curves,TN918.1
  9. Study on a Information Hiding Technology Based on Wavelet Domain and Visual Cryptography,TP309
  10. Research on Visual Cryptography Scheme for Cheating Prevention,TN918.2
  11. The Design and Implementation of 600MHz ALU of YHFT-DX,TP332
  12. Comparison and Analysis of Perceptron and BP Algorithms,TP183
  13. The Limitations of Human Category Learning from the Perspective of the XOR Task,B842.1
  14. The Research of Robust Image Watermarking Algorithm,TP309.7
  15. Research of All-Optical Logic XOR Based on SOA and Its Application in OCDM,O437
  16. Research on Linear Network Coding in All-Optical Multicasting Networks,TN929.1
  17. Dynamic multi- secret sharing scheme,TN918
  18. Research on the Consistent Degree of Addition Modulo 2~n and XOR,TN918.1
  19. Research on Optimizing Target in Cheater Preventable Visual Cryptography,TN918.2
  20. Study on Improving Coding Performance of Scalable Video Codec System,TN919.81

CLC: > Industrial Technology > Automation technology,computer technology > Computing technology,computer technology > General issues > Security and confidentiality
© 2012 www.DissertationTopic.Net  Mobile