A Three-Dimensional (3D) Space Permutation and Diffusion Technique for Chaotic Image Encryption Using Merkel Tree and DNA Code

This paper proposes image permutation and diffusion scheme based on 3D space. In addition, a new key processing method based on Merkel hash tree is proposed to improve the key sensitivity of the algorithm in the process of encryption and decryption. Firstly, this paper uses the Merkel hash tree and the plaintext image to generate the parameters required by the chaotic system and generates a chaotic sequence. Secondly, the image is transformed into a 3D matrix of bit level, and the chaotic sequence is used to spatially map and scramble it. Thirdly, DNA coding is performed to generate a 3D matrix of DNA level, which is performed by DNA operation of chaotic sequence. Diffusion operation based on 3D space. Fourthly, DNA decoding is performed to generate a ciphertext image. The algorithm only performs one round of encryption operation, which has good key sensitivity and plaintext sensitivity, and other aspects have reached the ideal security level, which is suitable for theoretical applications.