Revolutionary Chaotic Image Encryption Using Circular Shifts 🔐

Development of a chaotic image encryption algorithm.
Moysis, L., Lawnik, M., Alexan, W., Goudos, S. K., Baptista, M. S., & Fragulis, G. F. (2025). Exploiting Circular Shifts for Efficient Chaotic Image Encryption. IEEE Access.
https://ieeexplore.ieee.org/abstract/document/11009169
MATLAB code: https://uk.mathworks.com/matlabcentral/fileexchange/181195-circular-shifts-for-efficient-chaotic-image-encryption
MATLAB code in a GUI: https://uk.mathworks.com/matlabcentral/fileexchange/181208-gui-circular-shifts-for-efficient-chaotic-image-encryption

Full playlist: https://www.youtube.com/playlist?list=PL9y6bivP9mhEXxZGThfzyIJEZp5-BakCi

This work presents a chaotic image encryption algorithm that acts on the binary level of the image for effective permutation, and on the byte level for substitution. The permutation step combines actions of bit level rearranging, and bit shuffling. Circular shift operations are used for bit shuffling, to reduce the execution time. Circular shifts are also applied to shuffle the permutation and substitution rules, effectively increasing security at a very low execution cost. The encryption keys are plaintext dependent, and a key mixing step in included, so that each part of the key affects all the subsequent encryption operations. For the encryption, a new Soboleva hyperbolic tangent based map is first designed. The dynamical behavior of the map is studied and shows robust chaos, and an absence of equilibria, meaning that it can generate hidden attractors. This map is used as an entropy source, along with a chaotic pseudo random number generator. The encryption process shows a good performance under a collection of tests, and has also a low execution time, 0.0134 sec for a 256x256 image, 0.0530 sec for a 512x512 image, and 0.2050 sec for a 1024x1024 image.

Chaos-based encryption is a cryptographic technique that leverages the unpredictable and sensitive nature of chaotic systems to secure data. Unlike traditional encryption methods that rely on complex mathematical structures such as large prime factorizations or elliptic curves, chaos-based encryption uses nonlinear dynamical systems whose behavior is highly sensitive to initial conditions. A small change in the input or parameters leads to vastly different outputs, making it extremely difficult for an unauthorized party to reverse-engineer the encryption without precise knowledge of the system's initial state.

These methods are often used in multimedia encryption, such as image, video, and audio protection, due to their speed and efficiency in processing large volumes of data. By using chaotic maps—such as the logistic map, Lorenz system, or newer ones—chaos-based encryption can generate pseudo-random sequences that scramble and diffuse information effectively. Chaos-based encryption is still an evolving field with many open problems regarding standardization, key management, and resistance to various cryptanalytic attacks.

Social:
https://www.linkedin.com/in/moysislazaros/
https://www.researchgate.net/profile/Lazaros-Moysis

#chaos #chaostheory #encryption #cryptography #datasecurity #security #physics #mathematics #stem #dynamics #dynamicalsystems #cryptography #chaotic #nonlineardynamics #nonlinear #computerscience #science #physicseducation #butterflyeffect #mathematics #prbg #programming #χάος #bit #nonlinearsystems #prng #appliedmathematics