A Survey on Perceived Visual Quality and Secured Visual Cryptography Schemes
D. Madhavi, A. Vasu Devasastry · International Journal of Computer Applications · 2014
VC, EVCS and Color EVCS are the three techniques used for Visual Cryptography Schemes.Visual Cryptography Scheme (VCS) is one of the techniques used to encrypt the image by dividing the original image into transparencies called Shares.A set of qualified participants is able to recover the secret image.An Extended Visual Cryptography Scheme (EVCS) is a kind of VCS which consists of embedded random shares realized by embedding shares into covering shares.Color Visual Cryptography (VC) encrypts a color secret image into n color halftone image shares.Different methods for VC have different algorithms to provide cryptography for images.Two of the main areas of research in visual cryptography have been on improving the visual quality of the recovered image and the security of encrypted transparency shares.Generally, Visual Cryptography suffers from the deterioration of the image quality and security.Many authors are proposed different algorithms for these parameters.This paper describes the trade-off between the image quality and the security is discussed by comparing these VC schemes.