A leakage suppressed two-level security visual secret sharing scheme

This paper proposes a new scheme of visual secret sharing which serves two-level security for color images. The proposed scheme splits a secret color image into four pieces referred to as shares; a black-and-white mask share and three color component shares, namely, red, green, and blue. All shares in this scheme are random binary images and each share is delivered to a different user to keep the image secret. In the scheme, the secrecy of the image can remain intact even three color component shares are gathered, that is, two-level security is served. The conventional scheme having the above mentioned features has the risk of information leakage even without the mask share. In contrast, the proposed scheme suppresses the possibility of information leakage in exchange for introducing low contrast recovered images.