A construction method of (t, k, n)-privileged secret image sharing scheme

In conventional secret image sharing (SIS) schemes, all participants have identical roles, with the threshold k established based on the security level. However, in practical applications, certain participants have more power. Recently, Yang et al. introduced a (t, m, k, n)-privileged secret image sharing (PSIS) scheme that accords participants certain privileges, allowing the secret image to be recovered by any k out of n participants or by t out of m privileged participants (t < k). In this work, we present a construction method for a (t, k, n)-privileged secret image scheme, where both k out of n participants and t privileged participants can successfully reconstruct the secret image. Meanwhile, our scheme addresses and resolves the issues existing in the preceding scheme, such as parameter limitation and security issues. Theoretical analysis and experimental comparison demonstrate that our scheme is secure and efficient.