Multi Level Encryption Scheme for Transferring Secret image

Abstract

As the rapid development of Internet Technology, Security and Privacy of data being transmitted has become the major issue. Transfer of data securely and reliably has become one of the challenges. Security issues should be considering because hackers may utilize weak link over communication network to steal information. Cryptography is the technique used to keep the message secure. Many images transmitted via Internet containing secret information but not secure. Encryption technique which prevents unauthorized access of data. Visual Cryptography technique introduced by Naor and Shamir, in which secret image is divided into number of shares. No information about secret image is revealed from individual share. Decryption can be done by overlaying one share above the other share. In this paper the idea is to increase the security level as the basic model of Visual Cryptography is not an efficient tool to hide the information. The secret image is encrypted using Arnold’s Transformation technique in the first level. In the second level create two shares from encrypted image using basic (2, 2) Visual Cryptography technique. To increase the security level, instead of sending these shares to receiver, third level security is adopted. In third level security, shares are embedded in two host images using Chang and Yu’s method. Generated shares are embedded into respective host images so that the attacker cannot suspect the secret image in it. On the receiver end, shares are extracted from camouflage image and then stacked to get the encrypted image. Encrypted image is decrypted using Inverse Arnold Transformation.