Universal Share for Multisecret Image Sharing Scheme Based on Boolean Operation

Abstract

Conventional secret sharing schemes require complex computation. Visual secret sharing (VSS) scheme encrypts a secret into two or more meaningless images, called as shares. Shares are stacked together to decrypt a secret using human visual system. In recent years, concept of universal share is introduced to share multiple gray images. A company organizer uses this unique share to recover multiple images. However, utilization of complex numerical computation makes such system inappropriate for VSS. In this letter, we overcome this complexity issue and propose a Boolean-based light-weight computation scheme to share multiple secrets using universal share. The proposed Boolean-based multisecret sharing (MSS) scheme encodes n secret images into a universal share and n meaningless shares, and reconstructs lossless secret images. To provide threshold security, the proposed scheme uses random universal share generating function to generate a distinct universal share from base universal share for each secret image. Moreover, to enhance limited sharing capacity of the Boolean-based MSS scheme, we propose a modified Boolean-based MSS scheme.