An Image Encryption Scheme Based on Chaotic Map

In this paper, a novel block digital image encryption scheme based on a chaotic coupled map lattices (CML) is reported. Within this scheme, an original image is decomposed into sub-blocks with a given size, and an external secret key with 192-bit is used and mapped to the system parameters, which are employed to generate a spatiotemporal chaotic binary sequence matrix to encrypt the block original image. Besides, the former sub-block encrypted result will be acted as a feedback to the following sub-block encryption process. The proposed scheme is described in detail, along with the security analyses such as key space analysis, sensitivity analysis, information entropy analysis and correlation coefficients analysis of adjacent pixels. The computer simulation results indicate that the suggested image encryption scheme has some properties desirable in a good security cryptosystem.