Reconciling visual cryptography with an Etched photoengraving practice for an exceedingly secured secret image sharing

Abstract

Like a dictator, Information Technology is conquering us like; everything we touch has now been an ingredient of it and there has been an unremitting race between achieving security and breaking it like the one between viruses and anti-virus software releases. More specifically, when it comes to secure exchange of images it has been terrific. Naor mitigated it by putting forth visual cryptography exclusively for image encryption wherein a secret image is encoded into n shares and on reception, it cannot be retrieved viewing less than n shares under microscope. These insignificant shares are made meaningful through halftoning. Secret information pixels will be inserted into the half toned shares before coding. A few such methods are discussed in brief. The shares should not appear to be blurring since it will draw the attention of intruders. In this paper, a method has been proposed in which the engraved shares are error diffused continuously so that the shares can be so appealing. Error Diffusion is less complex and error filters are put to use to obtain high quality shares. This process is done through array of processors after optimal scheduling of pixels to obtain shares at a faster rate. To end with, the secret image can be retrieved by super positioning the eligible half toned shares. The image so obtained is comparatively better and is not susceptible to cross interference due to high PSNR.