Deterministic extended visual cryptographic schemes for general access structures with OR-AND and XOR-AND operations

In Visual Cryptographic Scheme (VCS) shares of the secret image look like random, whereas in Extended Visual Cryptographic Scheme (EVCS) the shares look like meaningful images. In the case of ideal contrast deterministic constructions for VCS, depending upon the access structure, each participant needs to hold one/multiple image shares with same size of the binary secret image and the secret image will be reconstructed without any change in resolution. In this paper, two deterministic constructions for EVCS with a relative contrast of 0.333 are proposed by utilizing the ideal contrast deterministic constructions for VCS as a building block. The proposed schemes are applicable to share secret binary images only. Theoretical analysis and comparison with other related works are given in this paper.