A new k out of n secret image sharing scheme in visual cryptography

摘要

Visual cryptography (VC) is a method for shielding the secret image which encodes the image into many shares and allocates them to various participants. When all shares are aligned and stacked together, they expose the secret image. In k out of n (k, n) VC scheme, the secret image is shared into n shares such that when k or more participants by amassing their transparencies by means of an overhead projector to reveals the secret image. This paper proposed a brand new of simple and robust (k, n) visual cryptography technique which is used to effectively sharing the secret image with utmost confidentiality. In share creation process, specified new condition for random matrices and then XOR operations are performed to generate the `n' transparencies. It is possible to decode the secret image visually by superimposing a k subset of transparencies. Nevertheless no secret data can be acquired from the superposition of an illegal subset. Experiments, statistical and security assessments are carried out on the shares to validate the strength of the proposed scheme by means of a sequence of investigations such as visual testing, encryption quality testing, security analysis and different attacks. The proposed (k, n) VC scheme offers a consistent protection for communicating images over the public channels.