A Secret Sharing Scheme for Digital Images Based on Cellular Automata and Boolean Functions

In this paper an efficient probabilistic secret sharing scheme for black and white digital images is introduced. It is an extension of the algorithm proposed originally in [11]. Specifically, it is a (m, n)-threshold scheme. It is based on the use of a simple matrix boolean function which involves the Hadamard matrix product modulo 2, and the addition modulo 2 and m. Moreover, an algorithm based on cellular automata is used for the enhancement of the recovered image. The algorithm introduced is shown to be secure and its expansion factor is equal to 1.