Moiré cryptography

As already pointed out by other researchers, one of the central problems with applicability of visual cryptography is the random nature of its secret shares. It makes secret shares not suited for carrying or for transmission over an open channel. In this paper, we apply concepts of steganography to create secret sharing schemes whose shares are realistically looking images. Our new technique is based on an idea of employing Moir e patterns for producing images. The advantage of this scheme over others is that it does not require a complicated algorithm, thus a computer, to decrypt the ciphertext. The cleartext can be read simply by putting the ciphertexts one onto the other. We therefore give a solution to the above mentioned problem with a novel type of visual secret sharing schemes, whose secrecy and anonymity are both satis ed.