This paper introduces an efficient prediction algorithm tailored for advanced and high efficiency video coding, encompassing both H.264 and H.265. The proposed approach aims at replacing the standard intra prediction methodology by employing a streamlined prediction mode, which significantly reduces computational overhead and system complexity while eliminating the requirement for mode decision. By leveraging block comparison criteria, the designed method combines neighboring blocks in a linear fashion to accurately represent the target block. Extensive comparisons are conducted with the H.264 intra prediction using various video sequences and multiple evaluation criteria. The results demonstrate substantial time savings of up to 60% compared to the H.264 standard intra prediction algorithm, with a minor peak signal-to-noise ratio drop. The proposed algorithm holds promise for enhancing real-time video processing and compression in video coding systems, offering notable efficiency gains without sacrificing predictive accuracy. © 2024 IEEE.
Pixel-based Visual Secret Sharing Using Lorenz System
(n, n)-Visual Secret Sharing (VSS) allows a user to send an image in the form of shares to different participants. Every share can not reveal the secret alone, and only all shares together can reveal the secret with fast recovery. This paper proposes a pixel-based (n, n)-VSS system, where to share a pixel from the secret image, (n – 1) random pixels are generated from the Lorenz chaotic system for a varying set of (n – 1) shares. Then, the nth pixel is calculated for a random share using the secret pixel and the generated (n – 1) random pixels. The system is efficient, lossless, implemented for grayscale and color images, and has a simple XOR-based recovery scheme. It passed several security analysis tests and is robust against noise attacks. Moreover, performance analysis and comparisons with other VSS systems are presented, showing good results. © 2023 ACM.
Double Visual Cryptography Using Generalized Tent Map, Rotation, and Image Filtering
This paper introduces a Multi-Visual Cryptography (MVC) system for sharing two color images, where the secrets can be revealed with low computation power using all the shares. The system uses the generalized Tent map as a source of randomness to generate any number of random shares. More specifically, (n-1) random shares are generated, and then, the nth share is calculated from the random shares and the secrets using rotations of the shares. In recovery, rotation of the last share recovers the two images based on the angle of rotation. Half the number of pixels is recovered for each secret image, whereas a modified weighted average filter is used to improve the quality of the recovered images significantly. The system does not use halftone images and produces shares of the same size as the secrets without pixel expansion or auxiliary data. The proposed system is efficient, passed several security tests, and is compared to recent works. © 2023 IEEE.
Generalized synchronization involving a linear combination of fractional-order chaotic systems
In this paper, a generalized scheme for synchronizing a fractional order chaotic system with another one or with a linear combination of two other fractional order chaotic systems is presented
Switched active control synchronization of three fractional order chaotic systems
This paper discusses the continuous effect of fractional order parameter on two chaotic systems
A Secured Lossless Visual Secret Sharing for Color Images Using Arnold Transform
Nowadays, with the rapid growth in information, a fast and secure method is eagerly needed to share images. (n, n)-Visual Secret Sharing (VSS) is used to share a secret image into n shares, where the secret can only be recovered using all the n shares and the recovery must be fast with low computational complexity. This paper proposes a secured lossless (n, n)-VSS system based on Arnold transform and pixel vectorization suitable to be used with binary, grayscale and color images. Multiple security tests were performed such as entropy, correlation, Mean Squared Error (MSE), National Institute of Standards and Technology (NIST) SP-800-22 statistical suite, and differential attacks, which demonstrate the good security of the proposed system. In addition, the time complexity and runtime of the recovery system indicate good efficiency. © 2022 IEEE.
Permutation techniques based on discrete chaos and their utilization in image encryption
To achieve the Shannon’s confusion and diffusion properties, an image encryption algorithm should include permutations and substitutions
The effect of multi-scrolls distribution on image encryption
This paper introduces two generalized tent maps where the conventional map is a special case
Permutation-Only FPGA Realization of Real-Time Speech Encryption
This paper proposes a speech encryption and decryption system, its hardware architecture design and FPGA implementation
A chess-based chaotic block cipher
This paper presents a new and efficient block cipher encryption system, which includes confusion as well as diffusion processes