An image encryption scheme based on chaotic tent map

Image encryption has been an attractive research field in recent years. The chaos-based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques. This paper proposes a novel image encryption scheme, which is based on the chaotic tent map. Image encryption systems based on such map show some better performances. Firstly, the chaotic tent map is modified to generate chaotic key stream that is more suitable for image encryption. Secondly, the chaos-based key stream is generated by a 1-D chaotic tent map, which has a better performance in terms of randomness properties and security level. The performance and security analysis of the proposed image encryption scheme is performed using well-known ways. The results of the fail-safe analysis are inspiring, and it can be concluded that the proposed scheme is efficient and secure.     

An efficient scheme for digital watermarking using chaotic map

This paper presents the new digital watermarking algorithm based on the chaotic map. Data can easily be hidden in images by using the least significant bits. In the anticipated algorithm, the logistic map is employed for locating embedding positions of chaotic watermark generation and a novel watermarking scheme is proposed. Simulation results reveal that the proposed technique is feasible and watermarks are indiscernible. The results illustrate that mean of energy, correlation, contrast, and homogeneity analyses of the proposed algorithm are quite optimal.     

An image encryption scheme based on a new hybrid chaotic map and optimized substitution box

Nonlinear Dynamics - This paper proposes a new hybrid chaotic map and a different way of using optimization technique to improve the performance of encryption algorithms. Compared to other chaotic...     

A new image alternate encryption algorithm based on chaotic map

In this paper, a new image alternative encryption algorithm is proposed, in which the shuffling and diffusion are performed simultaneously. The plain image is divided into two left and right blocks of same size. The matrix which is generated by a logistic map is used to diffuse the left block of the plain image. Then, the diffused image is used as the right block of the cipher image. The 0, 1 sequence which comes from another logistic chaotic sequence and plaintext is used to shuffle the right block of the cipher image. After the operation XOR, the left block of cipher image is generated. Finally, two new-generated blocks are merged into the cipher image. In order to get better effect for image encryption, this process can be repeated many rounds. The simulation results show that this algorithm has properties of big key space, high sensitivity to key, resisting statistical analysis, differential attacks, plaintext attacks, and chosen-plaintext attacks. So, it has high security and can be suitable for image encryption.     

An intertwining chaotic maps based image encryption scheme

In this paper, a new image encryption scheme is proposed that uses intertwining chaotic maps to enhance security and key length. In the substitution process, six randomly chosen odd integers are used to permute and then XORed with the first chaotic key to shuffle and alter the image pixels. Byte substitution has also been applied and the resultant values are XORed with the second chaotic key to improve the security against the known/chosen-plain text attack and to increase nonlinearity. In the diffusion process, the pixel values are altered sequentially with various operations which include nonlinear diffusion using the first chaotic key, subdiagonal diffusion of adjacent pixels and XORing with the third chaotic key. The security and performance of the proposed image encryption technique have been analyzed using statistical analysis, sensitivity analysis, key space analysis, differential analysis, and entropy analysis. The simulation shows that a single bit of key or pixel difference of the plain-image will change almost all the pixels in the cipher-image ( $\mathrm{NPCR}>99.63$ ?%), and the unified average changing intensity is high ( $\mathrm{UACI}>33.43$ ?%). Since the entropy is found to be close to the theoretical value, we observed that the information leakage is negligible, and hence the scheme is highly secure. The experimental results show that the performance of the proposed scheme is secure and fast.     

A parallel image encryption algorithm based on the piecewise linear chaotic map and hyper-chaotic map

This paper proposes a parallel digital image encryption algorithm based on a piecewise linear chaotic map (PWLCM) and a four-dimensional hyper-chaotic map (FDHCM). Firstly, two decimals are obtained based on the plain-image and external keys, using a novel parallel quantification method. They are used as the initial value and control parameter for the PWLCM. Then, an encryption matrix and four chaotic sequences are constructed using the PWLCM and FDHCM, which control the permutation and diffusion processes. The proposed algorithm is implemented and tested in parallel based on a graphics processing unit device. Numerical analysis and experimental results show that the proposed algorithm achieves a high encryption speed and a good security performance, which provides a potential solution for real-time image encryption applications.