Halftone visual cryptography for color images

Abstract

Visual cryptographic schemes (VCS) allow one(at the sender side) to encrypt a secret picture (image) into different share images. Here no share image does uncovers any knowledge concerning to the original secret image. This work proposes visual cryptography encryption framework by using an algorithm developed by Floyd and Steinberg's for error diffusion for grayscale as well as color images. Floyd Steinberg diffusion technique continuously delivers(generates) delighting colored halftoned images for our natural vision system of humans. A color image to be protected is taken as input and then this image is decomposed into three separate monochromatic images based on CMY color space. The computer simulation demonstrates that the visual nature and tone (in terms of quality) of the acquired halftoned shares is acceptable.