Papers by Keyword: Image Encryption

Abstract: Key space will be reduced after using the traditional DES algorithm to directly encrypt color images. Through combining the chaotic capability of the logistic function and by means of a specific algorithm, the fake chaotic son key’s space which is produced by the logistic chaotic pseudo-random function could be acquired. Then use the key generation algorithm to replace the traditional DES key generation algorithm. Experiment illustrates that the proposed algorithm has stronger robustness and anti-jamming capability to noise, and larger key’s space, sensitive initial keys, and better encryption effect, meanwhile it is better immune to multiple attacks.

Abstract: In a recent paper by Zhu and Zhao [1], an image encryption-compression scheme (IECS) based on hyper-chaos and Chinese remainder theorem (CRT) is proposed. This comment points out that in [1] there are some errors in two important algorithms and the performance of the proposed IECS is severely overestimated. It is shown that the IECS presented in paper [1] can be easily discredited and ipso facto cannot be used for compressing the plain image with a given compression ratio. Both theoretical analysis and experimental results are given to support our conclusion.

Abstract: In recent years, chaos-based image encryption technologies have been widely studied to meet the increasing demand for real-time secure image transmission applications. To overcome the drawbacks of small key space and weak security in many existing schemes based on low-dimensional chaotic maps, this paper suggests a security improved scheme with a permutation-diffusion architecture. In the permutation stage, baker map is employed to shuffle the pixel positions. In the diffusion stage, the value of each pixel is altered by using a key stream derived from hyperchaotic system. Compared with ordinary chaotic systems, hyperchaotic systems, with more complex dynamical behaviors and number of system variables, offer greater potential for secure cryptosystem construction. Extensive security analysis has been performed on the proposed scheme, including the most important ones like key space analysis, statistical analysis and key sensitivity, which has demonstrated the satisfactory security of the proposed scheme.

Abstract: Low-dimensional chaotic encryption has a good operational efficiency but there is a problem of security flaws, therefore this paper proposes a composite chaos encryption system based on double mapping. Double mapping with mutual disturbance were used to generate the key sequence, and respectively with odd and even number of image pixels to realize the image encryption. The simulation results show that, the effect is very good; Correlation and so on security analysis shows that meet the requirements of the security; System overall evaluation results show that the proposed algorithm has better security and ease of implementation, can effectively resist brute force attack, statistic attack etc.

Abstract: A novel image encryption scheme comprising of one permutation process and one diffusion process is proposed. In the permutation process, the image sized is expanded to one sized by dividing the plain-image into two parts: one consisting of the higher 4bits and one consisting of the lower 4bits. The permutation operations are done row-by-row and column-by-column to increase the speed. The chaotic generalized Arnold map is utilized to generate chaotic sequence, which is quantized to shuffle the expanded image. The chaotic sequence for permutation process is dependent on plain-image and cipher keys, resulting in good key sensitivity and plain-image sensitivity. To achieve more avalanche effect and larger key space, Chinese Remainder Theorem is applied to diffuse the shuffled image. The key sensitivity and key space of the proposed image encryption have been analyzed as well. The experimental results suggest that the proposed image encryption scheme can be used for secure image and video communication applications.

Abstract: This letter presents a new color image encryption scheme based on the coupled chaos maps. First, the algorithm uses the coupled logistic map to generate random strong key stream, and then designed a kind of initial simple diffusion-joint scrambling-combined diffusion method from the point of the relationships of components R, G, B. The simulation results indicate that this algorithm has stronger security compared with the independent encryption of each color component.

Abstract: This paper introduces a novel image encryption scheme based on chaotic maps and toggle cellular automata (TCA). In confusion stage, the proposed scheme utilizes logistic map to construct a nonlinear sequence for scrambling the plain-image. Then in diffusion stage, TCA is constructed by setting up the inversion rule and the image which has been processed by chaotic sequence is encryption again by using the TCA iteration method. Theoretical analysis and experimental results demonstrate the proposed algorithm achieves a high security level and processes good performance against common attacks like differential attack and statistical attack.

Abstract: Bit-plane decomposition makes images obtain a number of layers. According to the amount of data information, images are encrypted, and the paper proposes image encryption method with Chaotic Mapping based on multi-layer parameter disturbance. The advantage of multi-layer parameter disturbance is that it not only scrambles pixel location of images, but also changes pixel values of images. Bit-plane decomposition can increase the space of key. And using chaotic sequence generated by chaotic system with different complexities to encrypt layers with different information content can save operation time. The simulation experiments show that using chaotic mapping in image encryption method based on multi-layer parameter disturbance can cover plaintext effectively and safely, which makes it achieve ideal encryption effect.

Abstract: This paper designs an image encryption algorithm with a dynamical feedback operation based on sensitive chaotic system. In the proposed algorithm, the piece wise linear chaotic map is selected to construct pseudo-random keystream sequences. The pseudorandom keystream sequences are used to permute and substitute the plain image data. To enhance the complexity and security of the algorithm, each pixel is dynamically confused by its two previous adjacent encrypted pixels which are specified by a quantized binary tuple derived from a chaotic element. Both theoretical analysis and experimental tests show that the proposed algorithm is secure and efficient.

Abstract: For decades, symmetric cryptosystems, such as chaos-based ones, are designed for image encryption. In this paper, a novel public key scheme for image encryption is presented. Based on the improved elliptic curve cryptosystem and Arnold cat map, the novel scheme can offer high security while avoid exchange and distribution of secret keys. The experiments illustrate that the presented scheme is computationally less complex than the traditional asymmetric cryptosystems and suitable for large image encryption.