Abstract
This paper proposed an efficient confusion–diffusion chaotic image cryptosystem based on a modified Standard chaotic map. The proposed chaotic image cryptosystem employed image confusion and pixel diffusion in two phases. In the first phase, the plain image is shuffled by a modification of Standard chaotic map for n rounds. In the second phase, the shuffled image is diffused by Henon chaotic map. Then, the overall process is repeated m rounds. Comparison between Standard map and the proposed modification is held to prove the effectiveness of the proposed chaotic image cryptosystem. The experimental results show that the proposed chaotic image cryptosystem can successfully encrypt/decrypt images with the same secret keys with good encryption effect and large key space. Moreover, the simulation analysis demonstrates that the encrypted images have good information entropy and very low correlation coefficients, and the distribution of the gray values in the encrypted image has random-like behavior.