Novel authentication system using visual cryptography

An array of encryption techniques has been proposed for providing data security. However, most of the traditional cryptography methods require complex algorithms for encryption and decryption. Visual cryptography is a technique which provides confidentiality without any cryptographic knowledge or complex computations. Visual information (e.g. printed text, hand-written notes, pictures, etc.) is encrypted by decomposing it into several images, called shares, in such a way that decryption can be done by human visual system with stacking of the shares. Some important goals while developing a Visual Cryptography scheme is to have (i)optimum number of shares, (ii)good quality of reconstructed image and (iii)keeping the size of share small. This paper aims to provide a comparative study of various Visual Cryptographic schemes based on pixel expansion, no of shares, size and quality of reconstructed image, etc and some real-life applications of visual cryptography. A new authentication system has been proposed which uses the technique of visual cryptography to improve the security level of existing schemes. The application of the system in financial domain is discussed.