An Improved Method for Secret Image Sharing in Color Image through Error Diffusion

Visual Cryptography is the technique that divides the secret image into n number of shares. Each share consists of some information and when k shares out of n stack together the secret will reveal. However, less than k shares are not work. Color visual cryptography (VC) is a scheme of providing security to a color secret image by encrypting it into n color halftone image shares. A visual cryptogram scheme consists of an encryption algorithm by which a secret image is divided into a set of shares and a decryption algorithm which is used to recover the secret image by staking the shares. In this paper we introduced the concept of visual information pixel (VIP) synchronization and error diffusion to attain a color visual cryptography encryption method that produces meaningful color shares with high visual quality. VIP synchronization retains the positions of pixels carrying visual information of original images throughout the 3 color channels and error diffusion diffuses the errors generates shares pleasant to human eyes.