Secret image sharing using steganography with different cover images

Abstract

A novel approach to secret image sharing based on a (t,n)-threshold scheme with steganography is proposed. A secret image is first processed into n-shares which are then hidden in n-user selected different cover/camouflage images. Any t out of n participants can cooperate to reveal the secret data. The important essential of secret image sharing approaches is that the revealed secret image must be lossless. In the earlier visual secret sharing (VSS) scheme, the secret image can be shared by generating n random like images, called shadows or shares. The produced shadows can be transmitted instead of the original secret image. Once involved participants stack more than t shadows, the secret image can be revealed by visual perception without computation. But the generated shadows are often meaningless. A malicious intruder may be attracted to such meaningless shadows delivered over an insecure channel. To handle such meaningless threat, the steganography approach is utilized to embed the shadows in different cover images, called stego images. From visual perception, the content of the stego image is meaningful and can conceal the shadows from intruders .This scheme is a novel image sharing technique that satisfies all of the essentials of the traditional secret sharing scheme. The use of n different cover images further prevent the intruders from imagining an secret being transferred when compared to the shares being embedded into n similar cover images. © 2011 Springer-Verlag.