Random-grid based progressive visual secret sharing scheme with adaptive priority

This paper describes a random-grid-based progressive visual secret sharing scheme, wherein the priority weighting of each share can be adjusted. In this scheme, shares are recovered progressively to obtain a secret image. Therefore, with increasing number of shares that are collected, more information of the secret image is recovered, and vice versa. In addition, each user participating in the secret sharing can adjust the priority weighting of a share based on their determined level of secrecy; thus, each share generated by the proposed scheme has a different priority weighting value. During decryption, depending on the priority weightings of the stacked shares, the secret image can be recovered to different extents. Further, the priority level of these shares cannot be distinguished based on the average light transmission of the reconstructed image, thereby guaranteeing high security.