Novel image cryptosystem based on new 2D hyperchaotic map and dynamical chaotic S-box

Abstract

Chaotic systems are widely used in image encryption due to their sensitivity to initial values. and many image encryption algorithms based on chaotic systems have been studied in the past few years. In order to obtain a simpler encryption algorithm, this work firstly proposes a new two-dimensional discrete hyperchaotic map, which has a large chaotic interval and Lyapunov exponent, and then uses the map to generate two chaotic sequences, and use these sequences to generate three S-boxes, and combine them in pairs, and finally twelve S-boxes are obtained. Then, the elements of the plaintext image are grouped, each group of pixels is summed, and then modular operations are used to specify specific S-boxes. Next, each set of elements is bitwise XOR with the corresponding S-box. Finally, the cipher image is obtained by scrambling using chaotic signal.Experiments show that compared with some other encryption algorithms, the proposed S-box based encryption method has higher security, and it resists to common attack.

Design of S-box multi-objective optimization algorithm based on combined chaotic system

“…The homogeneity of the chaotic sequence obtained by the Henon mapping iteration is not high, and the distribution frequency is not uniform. Therefore, it introduces an improved Henon mapping chaotic sequence homogenization method [21], and the homogenization is as shown in equation (11):…”

“…Let the precision of the computer be 10 , r then the value space of the elements in the sequence is -10 ; r k according to the experiments, the integer between ( ( ( ))) ~r length X 2 l g , i where ( ) length X i represents the length of the sequence X . i After improving the Henon mapping chaotic sequence by the formula (11) and improving its sequence uniformity, the autocorrelation and cross-correlation of the sequence are also very good. Through the improved Henon mapping, we can generate sequences x and y, and their ranges are [−0.5, 0.5].…”

“…If each P i j , of the SAC correlation matrices is close to the optimal value of 0.5, then the S-Box is considered to satisfy the strict avalanche effect. 0.046875 0.132813 Hua [25] 0.054688 0.140625 Alshammari [26] 0.046875 0.132813 Zhou [11] 0.039063 0.132813 Shafique [27] 0.039063 0.148438 Hematpour [28] 0.039063 0.140625 Alsaif [14] 0.039063 0.148438 Zheng [29] 0.039063 0.125000 0.5051 Hua [25] 0.5352 Alshammari [26] 0.4949 Zhou [11] 0.5071 Shafique [27] 0.4980 Hematpour [28] 0.5037 Alsaif [14] 0.5100 Zheng [29] 0.5061 and…”

“…In summary, the approximate optimal S-box obtained by the multi-objective optimization algorithm an S-box with good cryptographic performance, which is suitable as the only nonlinear component of the lightweight cipher. [24] 102.79 0.4991 Hua [25] 103.21 0.4966 Alshammari [26] 102.29 0.4993 Zhou [11] 102.71 0.4991 Shafique [27] 103.64 0.5004 Hematpour [28] 102.86 0.5008 Alsaif [14] 104.29 0.4988 Zheng [29] 104.07 0.4994 (7) Time efficiency analysis…”

“…The new genetic algorithm significantly proposed improved the performance of generating S-boxes. Zhou S et al [11] proposed a new two-dimensional discrete hyperchaotic map with a sizeable chaotic interval and Lyapunov exponent and can generate good-performance S-boxes without using optimization methods. Lambić D [12] proposed a new one-dimensional discrete space chaotic map based on integer multiplication and circular shift, but it is simple to design the generation process of S-boxes only through simple Knuth shuffling.…”