Color image encryption algorithm based on bidirectional spiral transformation and DNA coding

Abstract

The security of digital images has become increasingly important as information technology has advanced considerably. To ensure image security and improve the efficiency of image encryption, a novel color image encryption algorithm is proposed in this paper. Firstly, a novel three-dimensional chaotic system with extreme multistability is proposed and employed to generate the chaotic sequences to be used in the permutation and diffusion processes. Secondly, the proposed bidirectional spiral transformation is used to permute the R, G and B components extracted from the color plain image. Thirdly, the permuted pixel sequence is dynamically encoded into a DNA sequence. To further increase the permutation effect, the DNA sequence is permuted again using the index sequence. Finally, the dynamical DNA operations are performed to diffuse the permuted DNA sequence, and the designed look-up table method is used to quickly obtain the DNA operation results. The key space of the proposed algorithm is 10266, which is large enough to resist the brute-force attacks. The average entropy value of the cipher image of Peppers is 7.9971, which is much closer to the theoretical entropy value 8. The dynamic DNA operations process only takes up 0.032349s, which shows the advantage of the proposed look-up table method. Therefore, the proposed algorithm can be applied to the application that require high confidentiality and real-time.

Image encryption algorithm based on 2D hyper-chaotic system and central dogma of molecular biology

“…Table 13 shows the comparison of encryption time for different algorithms based on genetic operations, where the image used in our experiment is the Peppers grayscale image of size 256 × 256. As can be seen, our proposed algorithm only takes 0.3572 seconds to encrypt the image, which is much faster than those algorithms in [40][41][42][43]. In addition, table 14 presents the execution time of each encryption step.…”

Color Image Encryption Algorithm Based on Cross-Spiral Transformation and Zone Diffusion

“…Therefore, the proposed algorithm is efficient and suitable for real-world scenarios of image transmission. [22] 256 × 256 × 3 256 × 256 1.1 s MATLAB Ref. [44] 512 × 512 × 3 512 × 512 2.5 s MATLAB Ref.…”

“…For the R, G, and B planes of color images, the left half of the region is scanned clockwise spirally, and then the right half of the area is counterclockwise. The scrambling effect of the proposed bidirectional spiral transformation is significantly better than that of the traditional spiral transformation [22]. Thangaraja et al designed a randomly selectable starting point of the spiral based on the chaotic map and used this helical transformation to scramble the plain image in a clockwise direction [23].…”

Image encryption algorithm based on improved iterative chaotic map with infinite collapses and Gray code

“…Wang et al designed a bidirectional spiral transformation, which can overcome the shortcomings of the traditional one. After the pixel-level permutation, a DNA-level permutation is used to further increase the scrambling effect [21]. Chen et al first split an image into different parts and then the designed V-shape traversal is used to respectively scramble each part.…”