A novel digital image encryption algorithm based on wavelet transform and multi-chaos

Digital image encryption is especially important in body area networks (BANs) applications since the image may contain some private or sensitive information. Past encryption methods have the disadvantages of a small key space and a low resistance to attack. In this paper, we propose a new encryption algorithm based on discrete wavelet transform (DWT) and multi-chaos. The image is first decomposed by DWT, and is then processed by multi-chaos matrices, which are deterministic, pseudo-random, and sensitive to initial values. The experimental results indicate that the proposed algorithm has a large key space, high key sensitivity and excellent resistance to attacks.