A novel chaotic block image encryption algorithm based on dynamic random growth technique

This paper proposes a new block image encryption scheme based on hybrid chaotic maps and dynamic random growth technique. Since cat map is periodic and can be easily cracked by chosen plaintext attack, we use cat map in another securer way, which can completely eliminate the cyclical phenomenon and resist chosen plaintext attack. In the diffusion process, an intermediate parameter is calculated according to the image block. The intermediate parameter is used as the initial parameter of chaotic map to generate random data stream. In this way, the generated key streams are dependent on the plaintext image, which can resist the chosen plaintext attack. The experiment results prove that the proposed encryption algorithm is secure enough to be used in image transmission systems. (C) 2014 Elsevier Ltd. All rights reserved.