Image Encryption Technology Based on Chaotic Hash Function and DNA Splicing Model

Image encryption based on chaotic maps is an important method for ensuring the secure communication of digital multimedia on the Internet. To improve the encryption performance and security of image encryption systems, a new image encryption algorithm is proposed that employs a compound chaotic map and random cyclic shift. First, a new hybrid chaotic system is designed by coupling logistic, ICMIC, Tent, and Chebyshev (HLITC) maps. Comparison tests with previous chaotic maps in terms of chaotic trajectory, Lyapunov exponent, and approximate entropy illustrate that the new hybrid chaotic map has better chaotic performance. Then, the proposed HLITC chaotic system and spiral transformation are used to develop a new chaotic image encryption scheme using the double permutation strategy. The new HLITC chaotic system is used to generate key sequences used in the image scrambling and diffusion stages. The spiral transformation controlled by the chaotic sequence is used to scramble the pixels of the plaintext image, while the XOR operation based on a chaotic map is used for pixel diffusion. Extensive experiments on statistical analysis, key sensitivity, and key space analysis were conducted. Experimental results show that the proposed encryption scheme has good robustness against brute-force attacks, statistical attacks, and differential attacks and is more effective than many existing chaotic image encryption algorithms.

An image encryption scheme based on new spatiotemporal chaos

In this paper, a new algorithm for designing one-way cryptographic hash function using chaotic Chirikov map is proposed. High sensitivity of Chirikov system makes it an ideal candidate for secure hash function design. In the proposed algorithm, the input message is split into a number of small blocks. The blocks are processed using chaotic map. The two intermediate hashes are generated using evolved control and input parameters. The two intermediate hash values are then employed to yield the final variable-length hash. The simulation and statistical analyses illustrate that the anticipated hash algorithm exhibits encouraging lineaments like high sensitivity to input messages and key, satisfactory confusion and diffusion attributes which verify the suitableness of proposed algorithm for the design of secure cryptographic variable-length hash functions.

Medical images include confidential and sensitive information about patients. Hence, ensuring the security of these images is a crucial requirement. This paper proposes an efficient and secure medical image encryption‐decryption scheme based on deoxyribonucleic acid (DNA), one‐dimensional chaotic maps (tent and logistic maps), and hash functions (SHA‐256 and MD5). The first part of the proposed scheme is the key generation based on the hash functions of the image and its metadata. The key then is highly related and intensely sensitive to the original image. The second part is the rotation and permutation of the first two MSB bit‐plans of the medical image to reduce its black background that produces redundant DNA encoded sequences. The third part is the DNA encoding‐decoding using dynamically chosen DNA rules for every 2‐bit pixel value through the logistic map. Meanwhile, the confusion‐diffusion is performed using the tent map and XOR operation. Simulation results and security analysis prove the good encryption effects of the proposed scheme compared to the state‐of‐art methods with a correlation of 6.66617e‐7 and a very large key space of 2 624 . Furthermore, the proposed system has a strong ability to resist various common attacks such as chosen/known‐plaintext attacks and cropping/noise attacks.

A novel devaney chaotic map with uniform trajectory for color image encryption

This paper proposes a color image encryption algorithm based on a cloud model Fibonacci chaotic system, as well as a matrix convolution operation that can protect image content effectively and safely. The algorithm combines the cloud model with the generalized Fibonacci, creating a new complex chaotic system that realizes the dynamic random variation of chaotic sequences. The chaotic sequence is used to scramble the pixel coordinates of the mosaic images of the R, G, and B components of the color image. Then, the chaotic sequence value is used as a matrix convolution cloud algorithm that alternately updates the input value of the matrix convolution operation and the pixel value to obtain the permutation transformation of the original pixel value. Finally, the pixel values of the replacement and cloud model Fibonacci chaotic sequence and the pixel values of the front (rear) adjacent pixel points are subjected to a two-way exclusive XOR operation. Realizing the change of the arbitrary pixel value causes a chain transformation of the pixel values of all of the pixel points, and sequentially generates an encrypted image. Experiments show that the histogram of the encrypted image is smoother and adjacent pixels of the image have low correlation. In addition, this algorithm can resist attack experiments such as differential attack, select plaintext attack and noise attack and provides high encryption security, high anti-interference, and strong robustness. The dynamic chaotic system is used to realize the color image encryption of the dynamic key, and the encryption algorithm has higher security and the validity of the algorithm.

Due to easy and simple implementation, normally single 1-D chaotic maps like logistic and sine maps are employed in multimedia data encryption. However, data encrypted through a single chaotic map does not provide better security in terms of resistance against various attacks. In this paper, 2D Henon chaotic map and skew tent map are deployed in the design of an efficient chaos-based image encryption algorithm. To confuse the relationship between plaintext and ciphertext images, both chaotic maps play a key role in the permutation and diffusion mechanism. In the confusion stage, firstly, the Henon chaotic map generates two different chaotic sequences, which are further applied in row and column permutation of plaintext image. The pixel values diffusion is produced by unimodal skew tent map via XOR operations. In the last stage of encryption algorithm, Hussain's substitution box is used to substitute each pixel into a new random pixel. Extensive security analysis and resistance to statistical attack prove the security of anticipated scheme.

By research on typical payment protocol of the PayWord, the paper points out its security problems, and presents a new mobile micropayment protocol based on chaotic hash function. This protocol generates pay certificate and encrypts order messages transmitted in the network with symmetric encryption algorithm. It also constructs secure chaotic hash function based on Henon-like mapping, and creates two payment chains using chaotic hash function in the protocol. The protocol is not only the anonymous concerning so that the user information which can ensure the confidentiality of the ordered message, but also realizes the partial fairness. Research results demonstrate that the new protocol has greater security and efficiency, and suits to those mobile micropayment transactions systems.

The rapid growth of online information transmission has made the secure transmission and storage of sensitive visual information crucial, particularly in light of the continuous increase in cyber threats. Traditional encryption algorithms are not very effective on images due to their very high pixel correlation, larger file sizes, and intrinsic redundancy. This paper presents a new framework of secure image encryption that will make use of advanced chaotic maps and cellular automata dynamics. It creates deterministic randomness, high sensitivity to initial conditions, and unpredictability through chaotic maps. CA introduces a series of dynamic, rule-based transformations that ensure robust properties for diffusion and confusion. During encryption, chaotic maps create pseudo-random sequences that control both the CA-based pixel scrambling and value transformation. This provides a very secure encryption method with many layers. It ensures high entropy in key generation, resistance against brute-force attacks, and high sensitivity to initial parameters. The scheme works because it can withstand differential, statistical, and noise-based attacks and show performance metrics like entropy analysis, correlation coefficients, histogram uniformity, and robustness. The suggested method is characterized by large-scale use, adaptability, and safety from modern cryptographic threats.

In this study, we presented a hybrid method of a new 4D hyper-chaotic system with DNA encoding for the encryption of RGB images. The suggested encryption algorithm consists of three stages: permutation, confusion, and DNA coding. First, color components are permuted utilizing the index of the chaotic sequences are constructed from the new chaotic system to remove the high correlation among adjacent pixels. Second, we performed the XOR between the chaotic sequences and the permuted image from the previous phase. Finally, a set of DNA processes (DNA addition, DNA XOR, and DNA subtraction) are performed between the DNA sequences of the confusing image with the DNA chaotic sequences to obtain the final encoded image. Through tests like key space, key sensitivity, information entropy, and the histogram, the simulation analysis shows that the suggested method is secure and effective, and it has the ability to resist various attacks.

Images are important information carriers in our lives, and images should be secure when transmitted and stored. Image encryption algorithms based on chaos theory emerge in endlessly. Based on previous various chaotic image fast encryption algorithms, this paper proposes a color image sector fast encryption algorithm based on one-dimensional composite sinusoidal chaotic mapping. The main purpose of this algorithm is to improve the encryption and decryption speed of color images and improve the efficiency of image encryption in the big data era. First, four basic chaos maps are combined in pairs and added with sine operations. Six one-dimensional composite sinusoidal chaos maps (CSCM) were obtained. Secondly, select the two best chaotic mappings LCS and SCS. The randomness of these two chaotic mappings was verified through Lyapunov index and NIST SP 800-22 randomness tests. Thirdly, the encryption process is carried out according to the shape of a traditional Chinese fan, and the diffusion and scrambling of each pixel of the image are performed in parallel. This greatly improves encryption speed. When diffusing, changing the value of one pixel can affect the values of multiple subsequent pixels. When scrambling, each pixel changes position with the three pixels before it according to the chaotic sequence. Finally, through many experiments, it is proved that the image encryption algorithm not only greatly improves the encryption and decryption speed, but also improves various indexes. The key space reached 2192, the average information entropy was 7.9994, the average NPCR was 99.6172, and the average UACI was 33.4646. The algorithm can also resist some common attacks and accidents, such as exhaustion attack, differential attack, noise attack, information loss and so on.

The main purpose of the proposed image encryption (IE) method is to enhance various security characteristics to protect sensitive images on the internet. In the literature, chaotic maps are preferred for image encryption because of their high randomness and sensitivity to initial parameter values. Therefore, metaheuristic algorithms have been utilized to fine-tune the parameters. In this research, we have employed the metaheuristic Lyrebird optimization (LO) algorithm to fine-tune the chaotic map parameters. The LO algorithm is chosen over other algorithms due to its better exploration and exploitation rate to search for the best solution. The LO algorithm searches for the best parameter value based on the objective function. This research involves the formulation of a multi-objective function that incorporates numerous security parameters, namely, entropy and correlation coefficient (CC), to improve the security attributes of the IE model. The proposed IE model has two steps. In the first step, a random key is generated to transform the pixels of the secret image, whereas in the second step, the image pixels are shuffled based on the shuffling index values to reduce the correlation among the neighboring pixels. In both steps, we have used the chaotic logistic map. The proposed IE is evaluated against statistical and differential attacks on the standard dataset by considering the various images and their different resolutions. The uniform distribution of the histogram of the encrypted images is validated using the chi-square test. Besides that, entropy analysis shows that the average entropy value is 7.9973, 7.9993, and 7.9998 for 256x256, 512x512, and 1024x1024 image resolutions. The average CC and SSIM are near zero value. The average NPCR value (>0.9969) is near the 1 value. Finally, the comparative analysis based on entropy, CC, and NPCR parameters shows that the proposed IE model outperforms the existing models.

New method for fingerprint images encryption using DNA sequence and chaotic tent map

SummaryThis paper develops a new image encryption algorithm based on a novel two‐dimensional chaotic map and bit‐level dynamic scrambling. First, multiple one‐dimensional chaotic maps are coupled to construct a novel two dimensions Logistic‐Sine‐coupling chaos map (2D‐LSCCM). The performance analysis shows that the 2D‐LSCCM has more complex chaotic characteristics and wider chaotic range than many extant 2D chaos maps. Second, original image matrix combines with hash algorithm SHA‐256 to generate a hash value. The initial values of 2D‐LSCCM are generated based on the hash value. Third, the original image matrix is divided into multiple sub‐matrices by wavelet transform, followed by scrambling by an improved Knuth shuffle algorithm. Fourth, the scrambled multiple sub‐matrices are stitched into an image matrix of and converted into a binary matrix. The chaotic sequence generated by 2D‐LSCCM is introduced as a control sequence to control the bit‐level scrambling of pixel points, which realizes the bit‐level dynamic scrambling. Finally, the diffusion operation is performed by parameter par and chaotic sequence to obtain the final encrypted image. The algorithm security analysis and simulation examples demonstrate the effectiveness of the proposed encryption scheme.

The research on the balance of chaotic sequence has important significance to spread-spectrum communication. The relationship between the balance and the parameter of four typical chaotic maps (Chebyshev, improved Logistic, Logistic and Tent) was discussed. The new numeric ranges of initial value and fractal parameter were decided, which provided reference for the generation of chaotic spread-spectrum sequence. Through the graphs of the four chaotic sequences' balance and the error-bit rate performance of these systems with the four chaotic sequences' map parameters, the new numeric ranges were validated. Both simulation results and the analysis show that the balance of Chebyshev is the best.