Cheating Prevention in Visual Cryptography - Visual Cryptography and Secret Image Sharing - page 288

TABLE 10.1
Comparisons of different cheating prevention visual secret sharing schemes.
Scheme Approach Access stru. Share gen. subpixels Security

Base matrices 2n 2

HCL1 Share auth. General

Base matrices 2(n + 1) 2 HCL2 Blind auth. k-out-of-n Secure

HT Share auth. k-out-of-n Base matrices 2n(n + 2)

n 2

TCH Blind auth. 2-out-of-n GA

Blind auth. 2(n)-out-of-n Base matrices 2(n + 1) 2 PS1 Secure

Base matrices n (2 n + n + 1) Secure PS2 Blind auth. 2-out-of-n

10.5 Conclusions
In this chapter, we have surveyed some cheating prevention schemes in visual
cryptography and provided a comparative evaluation of their advantages and
disadvantages. There are many topics that deserve further instigation, for
example, giving formal definition of cheating and cheating attack models and
designing new cheating prevention scheme a with less numbers of subpixels
for sharing a pixel.

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