A SURVEY ON VISUAL CRYPTOGRAPHY TECHNIQUES

ABSTRACT Visual Cryptography is a new technique for securing the visual information like picture, text etc. The basic idea of Visual Cryptography is that images are divided into several parts called shares. These shares are distributed among concerned participants and to decrypt them arrange or stacked to get the image back. At first there are various measures on which performance of visual cryptography schemes depends, such as pixel expansion, visual quality, image quality, contrast, security, quality of shares, size, computational complexity. Visual Cryptography techniques was developed for binary images only but later on it was advanced for colour images also. In this paper, we have done the literature survey on existing work which used different techniques for visual cryptography from 2011 to 2015. Keywords : visual cryptography, pixel expansion, visual quality, security, quality of shares.