Image Encryption of Multiple Keys Method Based on Chaotic Maps

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.

The chaotic functions and cyclic elliptic curves (CEC) has attracted many researchers, especially cryptographers, since decades. As CEC and chaotic functions meet the requirements of the cryptography, they are widely used either in key sequence generation or encryption/decryption process. Since in symmetric key encryption, stream ciphers need a large key sequence to encrypt/decrypt the information, authors propose a hybrid model to generate pseudo random sequence using CEC and logistic map. The hybrid model is developed using CEC points over and an one‐dimensional logistic map. In the proposed system, binary chaotic sequence and CEC points are given to AES S‐box to get two random sequences separately. Byte wise parity is computed for both the sequences. Based on the parity of both the bytes, one of the byte is left shifted and the other is right shifted by two positions in a circular manner. Later, both the bytes are combined using the XOR operation to get the random binary sequence. The generated sequences are analysed for randomness using various test suites like NIST, Correlation, FIPS, and TestU01. It has been observed that all the sequences pass the randomness tests. Using additive stream cipher, image encryption is implemented by considering the generated sequence as key sequence. The performance evaluation and security analysis of the encryption process is conducted. The results obtained for the proposed system indicate that the system is robust to withstand many cryptanalytic attacks.

This paper experimentally investigates the effect of nine chaotic maps on the performance of two Particle Swarm Optimization (PSO) variants, namely, Random Inertia Weight PSO (RIW‐PSO) and Linear Decreasing Inertia Weight PSO (LDIW‐PSO) algorithms. The applications of logistic chaotic map by researchers to these variants have led to Chaotic Random Inertia Weight PSO (CRIW‐PSO) and Chaotic Linear Decreasing Inertia Weight PSO (CDIW‐PSO) with improved optimizing capability due to better global search mobility. However, there are many other chaotic maps in literature which could perhaps enhance the performances of RIW‐PSO and LDIW‐PSO more than logistic map. Some benchmark mathematical problems well‐studied in literature were used to verify the performances of RIW‐PSO and LDIW‐PSO variants using the nine chaotic maps in comparison with logistic chaotic map. Results show that the performances of these two variants were improved more by many of the chaotic maps than by logistic map in many of the test problems. The best performance, in terms of function evaluations, was obtained by the two variants using Intermittency chaotic map. Results in this paper provide a platform for informative decision making when selecting chaotic maps to be used in the inertia weight formula of LDIW‐PSO and RIW‐PSO.

In the last decade, the communication of images through the internet has increased. Due to the growing demands for data transfer through images, protection of data and safe communication is very important. For this purpose, many encryption techniques have been designed and developed. New and secured encryption schemes based on chaos theory have introduced methods for secure as well as fast communication. A modified image encryption process is proposed in this work with chaotic maps and orthogonal matrix in Hill cipher. Image encryption involves three phases. In the first phase, a chaotic Henon map is used for permuting the digital image. In the second phase, a Hill cipher is used whose encryption key is generated by an orthogonal matrix which further is produced from the equation of the plane. In the third phase, a sequence is generated by a chaotic tent map which is later XORed. Chaotic maps play an important role in the encryption process. To deal with the issues of fast and highly secured image processing, the prominent properties of non-periodical movement and non-convergence of chaotic theory play an important role. The proposed scheme is resistant to different attacks on the cipher image. Different tests have been applied to evaluate the proposed technique. The results of the tests such as key space analysis, key sensitivity analysis, and information entropy, histogram correlation of the adjacent pixels, number of pixel change rate (NPCR), peak signal to noise ratio (PSNR), and unified average changing intensity (UCAI) showed that our proposed scheme is an efficient encryption technique. The proposed approach is also compared with some state-of-the-art image encryption techniques. In the view of statistical analysis, we claim that our proposed encryption algorithm is secured.

The current information age demands enormous opportunities, where, the sensitive data and information is being exchanged, analyzed and made use of. It has led to several concerns and challenges, mainly in the areas of information privacy, authentication and integrity. This concern, attracted cryptographers to device more effective methodologies and algorithms to ensure better protection to sensitive information. In this context, the application of chaotic based systems is considered to design a pseudorandom sequence generator, which is used as a key stream generator in the additive Stream Cipher system. Chaotic map is a mathematic function that generates highly nonlinear and random real sequence which is very sensitive to initial conditions. In this view, this work focusses on the study of Logistic map, considered from a bunch of various Chaotic functions available [1], [2]. Chaotic real sequence is binarized using a new binarization algorithm using Linear Feedback Shift Register (LFSR), which is designed in such a way that the randomness of Chaotic real sequence is not affected as far as possible. Using Logistic map, about 50 sequences are generated each of length ≥ 106. To ensure the randomness of binary sequences, NIST(National Institute of Standards and Technology) test is used. It is observed that, all the sequences have strictly passed most of the NIST tests with an average passing proportion ≥ 0.87. These sequences are used as key sequences in image encryption and decryption. It is interesting to observe that, encrypted image does not contain any residual information. This result is cross verified by plotting the Histogram, computing the Correlation coefficient and Entropy of the output images. It is observed that, Histograms are almost flat indicating the equiprobable distribution of pixels. Also, Entropy of the encrypted image is close to 8 and Correlation coefficient value is very negligible indicating that neighboring pixels are heavily uncorrelated. As the key sequence based on Chaotic functions is sensitive to initial conditions, the sequence generated will be highly nonlinear and random which encourages one to use in cryptographic applications.

In this paper, we present a novel approach to create the new chaotic map and propose an improved image encryption scheme based on it. Compared with traditional classic one-dimensional chaotic maps like Logistic Map and Tent Map, this newly created chaotic map demonstrates many better chaotic properties for encryption, implied by a much larger maximal Lyapunov exponent. Furthermore, the new chaotic map and Arnold's Cat Map based image encryption method is designed and proved to be of solid robustness. The simulation results and security analysis indicate that such method not only can meet the requirement of imagine encryption, but also can result in a preferable effectiveness and security, which is usable for general applications.

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.

Communication is essential to every society, and securely exchanging data are critical in the age of digital data. The image has been the center of interest for security; chaotic maps image encryption become widely used in recent years. In our study, authors assessed the pixel rearrangement (permutation) and pixel dissemination (diffusion) stage used in cipher image established on designed scheme Pseudo-random number Generators (PRNGs) and Logistic chaotic map. Logistic maps used to generate seed value for PRNG and two-permutation stage and PRNGs used in diffusion operation. The proposed design through experimental tests demonstrate decent Statistical output, and high security for our image encryption schema, Our PRNGs passed NIST SP 800-22, and TestU01 practical randomness test suggests PRNGs have suitable statistical property.

Recently, improvement of the internet usages, huge amount of multimedia data is transmitted through the network. The encryption method is introduced to secure the multimedia data for improve individual privacy, copyrights and other security reasons. In this paper proposed the LCA algorithm for chaotic logistic map based image encryption. Trendy this map of logistic parameter tuning is attained with the help of the LCA algorithm. The LCA algorithm is working based on the competition of sports teams in a league match. Various people as game groups contend in a league match for a few weeks; founded on the LCA process, logistic maps are tuned. The proposed algorithm for encryption is process constructed scheduled the two tasks such as confusion in addition diffusion. In confusion, produce the cipher image from the plain image by conversion. Second, the diffusion procedure is developed to diffuse the sequences equally. Here, the logistic maps parameters are taken as the encryption key. To prove the secure and reliable of the technique of proposed which is executed in the MATLAB and simulation results and performance analysis are described popular in paper. The presentation of proposed technique be there analysis through the way, statistical test and security test which is competitive with other freshly developed image encryption algorithm. To prove the efficiency of the proposed method which paralleled with the existing methods such as Firefly Algorithm (FA) and Particle Swarm Optimization (PSO) respectively.

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

Over the last twenty years, chaos-based encryption has been an increasingly popular way to encrypt and decrypt data using nonlinear dynamics and deterministic chaos. Discrete chaotic systems based on iterative maps have gotten a lot of interest because of their simplicity and speed. In this paper, three kinds of chaotic maps are utilized to build a digital image encryption strategy depending on a chaotic system. These chaotic maps are the logistic map, Arnold Cat’s map, and Baker’s map. In addition to using the triple data encryption standard (3DES) encryption scheme with the chaotic maps mentioned. The results of the experiments revealed that the suggested digital image encryption technique is both efficient and secure, making it ideal for usage in insecure networks. The transmission control protocol (TCP)/internet protocol (IP) protocol was used for the purpose of transferring data from server to client through the network and vice versa.

Image encryption scheme based on 3D baker with dynamical compound chaotic sequence cipher generator

A robust and secure chaotic standard map based pseudorandom permutation-substitution scheme for image encryption

Exponentially increasing multimedia data over the internet raises concerns over its security. In the current work, we present a new technique for encrypting digital images based upon the pixel shuffling combined with changing pixel values using 128-bit secret key using henon chaotic map. Chaotic maps are characterized by their high sensitivity towards the initial parameters, which makes it a natural choice for developing a dynamic permutation matrix or as it is mostly called, permutation map. So we used chaotic Henon map in order to dynamically generate the permutation matrix. The initial parameters of the chaotic map and the secret key for changing the pixel values are derived from an external secret key. Horizontal and vertical permutations are used to perform pixel shuffling. Shuffling is used to destroy the correlation among the neighbour or adjacent image pixels, also it helps in increasing diffusion in the image. The proposed scheme is tested against a series of tests to measure its performance. Results of such tests indicate that the proposed algorithm is highly sensitive towards the encryption key and showed high resistance against various brute-force or statistical attacks.

This paper contrasts the implementation of several chaos-based digital image watermarking techniques in terms of imperceptibility, robustness, security and complexity. Most spatial and transform domains methods have been used namely Least Significant Bit (LSB), Discrete Cosine Transform (DCT), Discrete Wavelet Transform (DWT) and Redundant Discrete Wavelet Transform (RDWT) with Singular Value Decomposition (SVD) mathematical tool which has enhanced embedding capability. Both continuous and discrete chaotic maps namely Arnold's Chaotic Map (ACM), Logistic Chaotic map (LCM) and Lorenz Chaotic Map (LoCM) are included to result in secure schemes. Exhaustive series of tests have been performed along with a range of evaluation metrics for imperceptibility evaluation. In addition, Robustness of all the techniques has also been confirmed by applying a variety of attacks on the resulting images. This study will help to adopt the most suitable methods for a given application as sufficient number of test images have been utilized.