A construction of a visual secret sharing scheme for plural secret images and its basic properties
Hiroki Koga, Masayuki Miyata · 2008
In this paper we discuss construction of the visual secret sharing scheme for plural secret images. We first consider generation of n shares for given two secret image SI1and SI2. For i = 1, 2, while no information of SIiis revealed from any less than n - 2 + i shares, SIiis visually recovered by the superimposition of arbitrary n - 2 + i shares. We define a new class of basis matrices used for generation of the n shares and give a simple construction of such basis matrices. In addition, a fundamental bound on the contrasts of SI1and SI2is established. These results are extended to the case where we have more than two secret images.