Weighted Threshold Secret Image Sharing

Abstract

Given a secret image I, a threshold r, and a set of n (≥ r) participants P = {1, 2, … , n} with a set of weights W = {w 1 , w 2 , … , w n } where w i is the weight (which indicates the degree/rank of importance) of participant i and we assume that w 1 ≤ w 2 ≤ … ≤ w n. The idea of weighted threshold secret image sharing encodes I into n shadows S 1 , S 2 , … , S n with sizes |S 1 | ≤ |S 2 | ≤ … ≤ |S n | in which S i is distributed to participant i such that only when a group of r participants can reconstruct I by using their shadows, while any group of less than r participants cannot. We propose a novel weighted threshold secret image sharing scheme based upon Chinese remainder theorem in this paper. As compared to the conventional Shamir's and recent Thien-Lin's schemes, which produce shadows with the same size, our scheme is more flexible due to the reason that the dealer is able to distribute various-sized shadows to participants with different degrees/ranks of importance in terms of practical concerns.

Improved Secret Image Sharing Scheme in Embedding Capacity without Underflow and Overflow

“…Also, SSIM (structural similarity) [ 39 ] has been used to evaluate the visual quality of the proposed scheme in terms of the human visual system and similarity, recently. The third hot issue is to enhance the ability of authentication, which aims to help in enhancing the security of schemes [ 4 , 6 , 7 , 9 , 29 , 35 ]. Decreasing the authentication bits with high authentication ability is a significant challenge [ 9 ].…”

“…Decreasing the authentication bits with high authentication ability is a significant challenge [ 9 ]. The fourth issue is to share color images securely [ 29 , 34 – 36 ], and recovering the distortion-free secret image and enhancing the security are two main problems. The fifth hot issue is to enhance the embedding capacity [ 32 , 36 – 38 ].…”

Essential secret image sharing scheme with the same size of shadows

“…, and etc. In fact, weighted SIS (WSIS) scheme [21][22][23] and essential SIS (ESIS) scheme [24][25][26] shadows. WSIS scheme generates shadows with different weights according to priority of the participant.…”

An Efficient Essential Secret Image Sharing Scheme Using Derivative Polynomial

“…In fact, there are many ways to generate different important shadows such as weighted SIS (WSIS) schemes, hierarchical SIS (HSIS) schemes and essential SIS (ESIS) schemes. In 2009, Shyu et al [13] utilized the Chinese remainder theorem to construct a WSIS scheme. In the sharing phase, the weight of the shadow for a participant is determined by its own privilege.…”