Two secret sharing schemes based on Boolean operations

Traditional secret sharing schemes involve complex computation. A visual secret sharing (VSS) scheme decodes the secret without computation, but each shadow is mm times as big as the original. Probabilistic VSS solved the computation complexity and space complexity problems at once. In this paper we propose a probabilistic (2,n)(2,n) scheme for binary images and a deterministic (n,n)(n,n) scheme for grayscale images. Both use simple Boolean operations and both have no pixel expansion. The (2,n)(2,n) scheme provides a better contrast and significantly smaller recognized areas than other methods. The (n,n)(n,n) scheme gives an exact reconstruction.