A novel image encryption algorithm based on hyper-chaos of Er-doped fiber laser

This letter presents a new image encryption scheme, which employs the two-dimensional discrete hyper-chaotic mapping to shuffle the positions of image pixels and then uses hyper-chaos of Er-doped fiber laser to confuse the relationship between the plain-image and the cipher-image. For decreasing the total encryption time, a certain "add-and-shift" operation for diffusion is introduced in the substitution stage. The experimental results demonstrate that the suggested encryption algorithm has the advantages of large key space, the encryption algorithm is very sensitive to the secret keys and plain-image and the distribution of grey values of the encrypted image has a random-like behavior. Furthermore, the proposed cryptosystem can achieve a high security level although only one total round of permutation and diffusion.