A new hyperchaotic map and its application for image encryption

Image privacy is getting more and more attention, so it is necessary to design a secure and efficient image encryption algorithm. This paper proposes a novel Logistics-Henon-Memristor Coupled Chaotic Map (LHM-CCM), which exhibits high sensitivity to system parameters as demonstrated by Lyapunov exponents, bifurcation diagrams, offset-boosting analysis and extreme multistability. Based on this system, a non-uniform pixel segmentation image encryption algorithm with multiple randomization elements is introduced, dynamically controlling pixel segmentation using a hash matrix. The Josephus scrambling and bit-plane reconstruction achieve disruption and diffusion, respectively. It shows excellent performance in terms of sequence randomness, resistance to attacks, key security, and robustness against interference. Moreover, encrypting a 256 × 256 grayscale image only takes 0.0696 s. The proposed algorithm demonstrates significant advantages in encryption and decryption efficiency while ensuring security.

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.

Advancement of medical imaging in health care sector emerges new challenge of secure image transmission. Security of medical imaging is a prominent issue to keep patients information safe. In this paper an efficient and secure biomedical image encryption algorithm is proposed with two phases of encryption. In the first phase the image has to undergone a random substitution of 20 Amino Acid based Codon with one or more than alternate Codon in the form of triplets using the base DNA code (A, T, C and G) using Linear Congruential Generator. Upshot of the first phase encrypted image is divided into blocks and a logistic map is used to generate a series of unique initial condition and control parameter. Using a random ASCII character as a seed the unique initial conditions for each block is generating some Pseudo Random Number Generator. The seed is encrypted using RSA. Each block is circularly shifted using unique PRNG. These unique initial conditions and control parameters are utilized by a series of Tent Maps to perform block by block confusion in the second phase encryption using XOR operation. Keys used in both the phases are encrypted using AES technique. Proposed method is used to encrypt any biomedical and other images also. All type of security measure such as Differential attack, key space analysis to resist Brute force attack, Correlation analysis, key sensitivity test, resistance to Noise attack and plain text attack along with time analysis has been taken into consideration to test the vulnerability of the proposed algorithm. From the comparative study the proposed method outperform in many aspects than the existing methods.

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

A new image encryption method based on memristive hyperchaos

Considering a nonlinear dynamic oscillator, a high Lyapunov exponent indicates a high degree of randomness useful in many applications, including cryptography. Most existing oscillators yield very low Lyapunov exponents. The proposed work presents a general strategy to derive an n-D hyperchaotic map with a high Lyapunov exponent. A 2D case study was analyzed using some well-known nonlinear dynamic metrics including phase portraits, bifurcation diagrams, finite time Lyapunov exponents, and dimension. These metrics indicated that the state of the novel map was more scattered in the phase plane than in the case of some traditional maps. Consequently, the novel map could produce output sequences with a high degree of randomness. Another important observation was that the first and second Lyapunov exponents of the proposed 2D map were both positive for the whole parameter space. Consequently, the attractors of the map could be classified as hyperchaotic attractors. Finally, these hyperchaotic sequences were exploited for image encryption/decryption. Various validation metrics were exploited to illustrate the security of the presented methodology against cryptanalysts. Comparative analysis indicated the superiority of the proposed encryption/decryption protocol over some recent state-of-the-art methods.

A new 2D-HELS hyperchaotic map and its application on image encryption using RNA operation and dynamic confusion

Bit-level and pixel-level methods are two classifications for image encryption, which describe the smallest processing elements manipulated in diffusion and permutation respectively. Most pixel-level permutation methods merely alter the positions of pixels, resulting in similar histograms for the original and permuted images. Bit-level permutation methods, however, have the ability to change the histogram of the image, but are usually not preferred due to their time-consuming nature, which is owed to bit-level computation, unlike that of other permutation techniques. In this paper, we introduce a new image encryption algorithm which uses binary bit-plane scrambling and an SPD diffusion technique for the bit-planes of a plain image, based on a card game trick. Integer values of the hexadecimal key SHA-512 are also used, along with the adaptive block-based modular addition of pixels to encrypt the images. To prove the first-rate encryption performance of our proposed algorithm, security analyses are provided in this paper. Simulations and other results confirmed the robustness of the proposed image encryption algorithm against many well-known attacks; in particular, brute-force attacks, known/chosen plain text attacks, occlusion attacks, differential attacks, and gray value difference attacks, among others.

Chaos and compressive sensing based novel image encryption scheme

A color image encryption scheme based on 1D cubic map

A novel memristive chaotic circuit is proposed by replacing the Chua’s diode in modified Chua’s circuit with a smooth active memristor, and the corresponding memristive model is analyzed and validated. The equilibrium point set, dissipativity and stability of this new chaotic circuit are developed theoretically. The dynamic characteristics for the new system are presented by means of phase diagrams, Lyapunov exponents, bifurcation diagrams and Poincare maps. The coexistence of the memristive system is carried out from the perspective of asymmetric coexistence and symmetry coexistence. In addition, the coexistence of multiple states is studied by a more direct method with initial value as the system variable to gain a more intuitive observation. The circuit model of the memristive chaotic system is designed through Multisim simulation software. Finally, the memristive chaotic sequence is used to encrypt the image, and the influence of multistability on the encryption is investigated by the histogram, correlation and key sensitivity. The results show that the proposed new memristive chaotic system has high security.

Design and realization of discrete memristive hyperchaotic map with application in image encryption

We devise a color image encryption scheme via combining hyperchaotic map, cross-plane operation and gene theory. First, the hyperchaotic map used in the encryption scheme is analyzed and studied. On the basis of the dynamics of hyperchaotic map, a color image encryption scheme is designed. At the end of the encryption process, a DNA mutation operation is used to increase the encoding images’ randomness and to improve the encryption algorithm’s security. Finally, simulation experiments, performance analysis, and attack tests are performed to prove the effectiveness and security of the designed algorithm. This work provides the possibility of applying chaos theory and gene theory in image encryption.

This paper proposes a visually secure asymmetric image encryption scheme based on Rivest–Shamir–Adlemen (RSA) algorithm and hyperchaotic map. It combines the advantages of the RSA and chaos-based image encryption algorithms. First, to fully encrypt the image information, the plain image is encrypted into a cipher image by applying the row and column encryption algorithms. Second, the image secret key is converted into a ciphertext by utilizing the RSA algorithm to increase the security, and then the ciphertext is transformed into an image and permuted using the Arnold map to enhance the robustness of the embedded image. We then obtain the key cipher image. Finally, the cipher image and the key cipher image are embedded into a carrier image (CI) to obtain a visually secure image. It simultaneously achieves the image information security and image visually security. To further improve the security, the RSA keys management technique is applied and the initial conditions of the hyperchaotic map are updated in real time based on the plain image. In addition, the encryption scheme is suitable for multi-user image transmission with high security requirements and image transmission without the secure channel for key transmission. The simulation results and performance analysis validate the effectiveness, security and robustness of the proposed scheme.

Chaos-based encryption has emerged as a promising approach for securing digital images, particularly in sensitive domains such as medical imaging. However, existing chaos-based encryption algorithms often suffer from design flaws and the use of weak chaotic maps that exhibit limited chaotic ranges and vulnerability to signal estimation. These limitations result in insufficient key space, reduced resistance to statistical and differential attacks, and inefficiency in real-time applications. To address these challenges, this study introduces a novel 1D Cosine-Exponential (1DCE) map, a hypersensitive chaotic map characterized by enhanced chaotic behavior and robustness. Leveraging the 1DCE map, we propose a real-time image encryption algorithm, termed DCEIES, which incorporates a cross-row-column encryption strategy to significantly improve both encryption speed and security. The DCEIES algorithm also integrates a novel image sensitivity function that detects any alterations in the plain image, rendering the cryptosystem resistant to differential attacks. While the DCEIES algorithm is versatile and applicable to various types of images, its design is particularly optimized for medical imaging, where high pixel correlations and sensitivity to input changes are critical. Extensive simulations and security analyses demonstrate that the DCEIES algorithm outperforms state-of-the-art encryption algorithms in terms of high security and computational efficiency. The results highlight the potential of the DCEIES algorithm for real-time medical image encryption.