Fault-Tolerant Visual Secret Sharing Schemes without Pixel Expansion

Abstract

Abstract:Visual cryptography encrypts a secret image into two meaningless random images, called shares, such that it can be decrypted by human vision without any calculations. However, there would be problems in alignment when these two shares are staked by hand in practice. Therefore, this paper presents the fault-tolerant schemes of stacking two shares that are acquired from secret image encryption without pixel expansion. The main idea of these schemes is to combine several pixels as a unit and then to encrypt each unit into a specific combination of pixels. Both theoretical analysis and simulation results demonstrate the effectiveness and practicality of the proposed schemes.

Fault-Tolerant Visual 2-Secrets Sharing Scheme

“…In 2016, Chen and Juan proposed a new fault-tolerant VSS scheme with no pixel expansion [2]. The main concept of that algorithm is as follows.…”

“…(2) It needs a storage space to record codebook to cause the cost increased. Kafri and Keren had proposed a random grid visual secret sharing (RG-based VSS) scheme [2], which regards each pixel on image as a grid and encrypt image by the concept of random variables. So that their scheme will causes no pixel expansion after the encryption, and it needs no codebook.…”

“…So that their scheme will causes no pixel expansion after the encryption, and it needs no codebook. In recent years, more and more researches about VC by using random grids has been proposed, such as references [2,3,4,5,6,7,8,9,10,11,12]. be encrypted and still avoid the problems of pixel expansion and codebook redesign, Chang and Juan proposed one RG-based MVSS scheme by shifting random grids, called OSRG scheme [3,4].…”

“…The difference is that the encryption pattern of the code book is modified so that there are some space for fault tolerance when reconstructed the secret image. According to the idea of [13], Chen and Juan proposed a new fault-tolerant VSS scheme with no pixel expansion in 2016 [2]. In this paper, we will refer to the ideas of [2] and [4], then design a new visual 2-secret sharing scheme with no pixel expansion, and to achieve the fault-tolerant mechanisms.…”

Strong Aftershock Study Based on Coulomb Stress Triggering—A Case Study on the 2016 Ecuador Mw 7.8 Earthquake

“…It was thought that small coulomb stress changes can alter the likelihood of earthquakes on nearby faults [7,8]. The occurrence of earthquake activity can be promoted when the coulomb stress increases as little as 0.1 bar on a seismogenic fault [9,10]. Small positive changes in coulomb stress due to an earlier mainshock can trigger subsequent earthquakes.…”