Image Encryption Using a Novel Chaotic Map

A new image encryption algorithm is proposed, in which a novel chaotic map is introduced to generate the random sequence. The mentioned sequence is employed to produce gray level values. The original image is encrypted by applying the XOR operator to every pixel using the mentioned values. Our chaotic map provides a large degree of randomization compared to existing approaches and therefore, the correlation between adjacent pixels in the encrypted image is reduced substantially. The security analysis demonstrates that the new algorithm is highly secure. As it is shown in the experimental results, our algorithm improves entropy, key sensitivity, and correlation. Specifically, the amounts of entropy and correlation measures are very close to the optimal values. It is also very robust against the noise. The PSNR of decrypted images are degraded slightly with the increasing noise strength. Additionally, the suggested approach leads to smoother histograms in comparison to the previous algorithms.