Visibility bounds for visual secret sharing based on JND theory
Visual secret sharing (VSS) is a noteworthy variant of secret sharing. One special property of VSS is that the security of VSS is achieved by loosing the contrast and the resolution of the secret image. Generally, the reconstructed secrets of these schemes are considered to be visible if and only if the contrast is greater than 0. However, VSS is based on the human vision system (HVS), thus the visibility is not only dependent on the contract. In this paper, we discuss the limit of human vision for VSS (LHV-VSS), because HVS is actually complicated. We take several human vision parameters into consideration, and propose a profile to analyze the upper bound of n for k-out-of-n VSS schemes based on the just noticeable difference (JND) profile. We conclude some cases of VSS schemes are invisible practically according to the analyses. Finally, we give a definition for VSS, visibility condition.
visual secret sharing human vision system just noticeable difference