International Journal on Computer Science and Technology (IJCST)
Visual cryptography is a cryptographic technique which encrypt a visual information (e.g. text, handwritten notes and pictures) in such a way that the decryption done by the human visual system. It needs neither cryptography knowledge nor complex computation. For security purpose, it also ensures that hacker cannot obtain any clues about a secret image from individual shares. The researchers proposed the basic model of visual cryptography in 1994. Visual cryptography scheme eliminates complex computation problem at the decryption the secret images can be restored by stack operation.