Presentation of encryption method for RGB images based on an evolutionary algorithm using chaos functions and hash tables

In this study, a new method based on chaos functions, and the evolutionary algorithm is proposed for image encryption. Chaos functions are used in this method because of the random occurrence and the sensitivity to the initial values to make the encryption method as secure as possible. Also to enhance the entropy of the image, an evolutionary algorithm is used to select the best layout and mapping. For this purpose, the image is decomposed first. The image components are then disrupted using the evolutionary algorithm, coding rules, and logistic mapping whose initial value is obtained from a hash function. The results show that the proposed method has good speed due to the use of simple operators such as Addition and XOR. Also, since a 256-bit hash function is used in this case and a high search space is generated for the evolutionary algorithm, the algorithm shows good resistance to the types of attacks. Moreover, due to the uncertainty of the decryption algorithm and the generation of a single-use code for each execution of the algorithm, the proposed encryption algorithm offers high security and resistance against differential attacks and plaintext attacks.