An Image Visual Cryptography Using Double Encryption and Hiding Technology

In this paper, an image visual cryptography based on double encryption and hiding technology is proposed. The secret plain-image is scrambled, added under modulo operation and cyclically left-shifted to obtain the pre-encrypted image. Carrier image is also encrypted by scrambling and diffusion, and then the pre-encrypted image is embedded into the encrypted carrier image by lifting wavelet transform (LWT) and QR decomposition. As a result, the final encrypted carrier image with encrypted secret image is generated. After realizing double visual encryption and hiding technology, attacker cannot know that the meaningless of encrypted carrier image containing an encrypted secret image. Chaotic sequences used in the scrambling and diffusion stages are generated by a 2D logistic-sine-coupling map (2D-LSCM), which is related to secret plain-image and can resist effectively the known-plaintext and chosen-plaintext attacks. Experimental results show that the proposed algorithm has high security and good application prospects.