Color image encryption based on DNA encoding and pair coupled chaotic maps

Information security has become a significant issue in encryption due to the rapid progress of internet and network. Therefore, the development of the encryption algorithm is a growing and significant problem. In this study, a new color image encryption was introduced based on DNA complementary rules and pair coupled chaotic maps. At first, the plain color image was divided into three components (R, G, B) being converted into three DNA matrices using DNA encoding rules. Secondly, DNA addition for R, G and B components was implemented and scrambled the elements position of three DNA sequence via the pair coupled chaotic maps. Three gray coded images obtained and RGB encrypted image was achieved by restructuring R, G, B components. The simulation of experimental result and security analysis showed that this algorithm had larger secret key space and strong secret key sensitivity and it had excellent ability to resist against statistical and differential attacks.

     

Adaptive image encryption based on twin chaotic maps

Multimedia Tools and Applications - The information stored or shared via the internet is growing massively and includes images primarily. The images are vulnerable to attacks when transferred over...     

基于多混沌系统的彩色图像加密方法

为了提高彩色图像加密的安全性和加密性能,设计了一种基于多混沌系统的彩色图像加密方法.将一个彩色图像分解为R、G、B三个灰度图像,使用MD5算法动态生成加密算法的初始值,然后使用三种不同的基于混沌的加密结构对三个图像进行加密.对R图像使用Feistel结构加密,其中Feistel结构的S一盒由Logistic混沌序列和Hyperhenon混沌序列组合产生;对G图像使用由Lorenz系统产生加密序列对图像进行代替和置换操作的加密结构;对B图像使用由分段线性混沌映射产生加密序列,然后加密图像的加密结构,再把加密后的图像结合起来生成加密后的图像.理论分析和实验结果表明,该加密方法能够较为有效地保证彩色图像加密的安全性.     

彩色图像的混沌加密算法

提出了一种新的基于Lorenz混沌系统的彩色图像加密算法。对Lorenz系统输出的实值混沌序列进行改进,使之近似均匀分布,得到更适合图像加密的伪随机序列。利用改进后的序列生成置乱和变换矩阵,按规则分块对彩色图像三基色分量进行置乱和按位异或等加密运算。仿真实验和安全性分析的结果表明,该算法密钥空间大,具有较好的加密效果和加密效率,且具有较好的抗干扰性。     

基于双混沌映射的快速图像加密新算法

提出了一种结合Logistic映射和混合光学双稳模型的对混沌图像加密算法。由Logistic映射和混合光学双稳模型产生的混沌序列分别用来产生图像加密密钥,利用反馈技术增强抵抗各种密码攻击的鲁棒性。仿真结果表明,该密码系统的时间开销很小、密钥空间足以抵抗强力攻击、密文对明文或初始密钥的任何微小变化均有强烈敏感性、密文分布均匀、相邻像素满足零相关性。故该密码系统具有高安全性。     

Symmetric keys image encryption and decryption using 3D chaotic maps with DNA encoding technique

In present digital era, multimedia like images, text, documents and videos plays a vital role, therefore due to increase in usage of digital data; there comes high demand of security. Encryption is a technique used to secure and protect the images from unfair means. In cryptography, chaotic maps play an important role in forming strong and effective encryption algorithm. In this paper 3D chaotic logistic map with DNA encoding is used for confusion and diffusion of image pixels. Additionally, three symmetric keys are used to initialize 3D chaos logistic map, which makes the encryption algorithm strong. The symmetric keys used are 32 bit ASCII key, Chebyshev chaotic key and prime key. The algorithm first applies 3D non-linear logistic chaotic map with three symmetric keys in order to generate initial conditions. These conditions are then used in image row and column permutation to create randomness in pixels. The third chaotic sequence generated by 3D map is used to generate key image. Diffusion of these random pixels are done using DNA encoding; further XOR logical operation is applied between DNA encoded input image and key image. Analysis parameters like NPCR, UACI, entropy, histogram, chi-square test and correlation are calculated for proposed algorithm and also compared with different existing encryption methods.

     

A secure image encryption scheme based on three different chaotic maps

Multimedia Tools and Applications - In the current decade, chaos based image encryption has distinctly captured a remarkable position in multimedia data security. In this paper, a hybrid chaos...     

A secure image encryption scheme based on chaotic maps and affine transformation

Due to the interesting nonlinear dynamic properties of chaotic maps, recently chaos-based encryption algorithms have gained much attention in cryptographic communities. However, many encryption schemes do not fulfil the minimum key space requirement, which is an essential concern in many secure data applications. In this paper, an efficient chaos-based image encryption scheme with higher key space is presented. Even with a single round of encryption, a significantly larger key space can be achieved. The proposed scheme removes correlation among image pixels via random chaotic sequences, simply by XOR and addition operations. In order to resist against numerous attacks, we apply the affine transformation to get the final ciphertext image. The security of the proposed scheme is proved through histogram, contrast, PSNR, entropy, correlation, key space, key sensitivity and differential attack analysis. Many significant properties of chaotic maps, sensitivity to initial condition and control parameters, structure and attack complexity, make the anticipated scheme very reliable, practical and robust in various secure communication applications.     

A robust image encryption algorithm resistant to attacks using DNA and chaotic logistic maps

An image encryption technique using DNA (Deoxyribonucleic acid) operations and chaotic maps has been proposed in this paper. Firstly, the input image is DNA encoded and a mask is generated by using 1D chaotic map. This mask is added with the DNA encoded image using DNA addition. Intermediate result is DNA complemented with the help of a complement matrix produced by two 1D chaotic maps. Finally, the resultant matrix is permuted using 2D chaotic map followed by DNA decoding to get the cipher image. Proposed technique is totally invertible and it can resist known plain text attack, statistical attacks and differential attacks.     

基于四维超混沌系统的彩色图像加密算法

针对彩色图像在加密过程中数据量大、相邻像素相关性强及冗余度高等缺陷,提出基于新四维超混沌的彩色图像加密算法.利用混沌性能更好的四维超混沌系统与反向传播神经网络结合进行序列融合运算,生成伪随机性更好的融合序列作为密钥流;利用密钥流对彩色图像像素块进行位置置乱及像素扩散运算,得到最终的密文图像.仿真计算结果表明,该加密算法...     

A novel chaotic image encryption technique based on multiple discrete dynamical maps

The propagation of information over insecure communication system is one of the most important aspect of digitally advance era. The electronic information is travels in form of binary bits. The secrecy of these digital contents is one of the most important issue of existing world. In this article, we have utilized multiple chaotic iterative maps in order to propose a novel image encryption technique. The suggested encryption added confusion as well as diffusion in offered scheme which is one of the most fundamental aspect of encryption technique. We have tested our anticipated scheme against different performances analysis and compared it with already existing results. The designed scheme is capable of providing an excellent privacy to digital images.

     

基于改进的CAT置乱与Henon_Kent混沌系统的彩色图像自适应加密算法

为了解决彩色图像加密算法中密钥与明文图像不关联的安全性不足以及CAT映射成立条件的问题,提出一种基于改进的CAT置乱系统与Henon_Kent混沌扩散系统的彩色图像自适应加密算法。该算法首先利用明文图像特征信息生成密钥;然后通过改进的CAT置乱系统对图像进行像素位置的三维置乱,再将Henon_Kent混沌系统所产生的三个混沌序列分别对RGB三个通道的像素灰度值进行扩散;重复以上两个步骤,以密文图像的信息熵大于7.99为结束条件。仿真表明该算法能够抵抗现有的攻击方法,具有较强的加密性能。     

A novel image encryption algorithm based on piecewise linear chaotic maps and least squares approximation

In this paper, we propose a novel image encryption algorithm based on chaotic maps and least squares approximations. The proposed algorithm consists of two main phases, which are applied sequentially in several rounds, namely a shuffling phase and a masking phase. Both phases are based on 1–dimensional piecewise linear chaotic maps and act on the rows/columns of the input plain image. Least squares approximations are used to strengthen the security of the proposed algorithm by providing strong mixing between the rows/columns of the image. Simulation results show that the proposed image encryption algorithm is robust against common statistical and security attacks. We present thorough comparison of the proposed algorithm with some existing image encryption algorithms.

     

A robust image encryption scheme based on chaotic system and elliptic curve over finite field

Multimedia Tools and Applications - The paper proposes a robust image encryption scheme based on chaotic system and elliptic curve over a finite field. The sender and receiver agree on an elliptic...     

混沌映射与比特重组的图像加密

目的 当前很多图像加密都采用基于比特的加密算法。针对这种比较流行的加密算法所存在的安全缺陷问题,提出一种能够解决比特面0比特和1比特置乱时的位置限制的图像加密算法,实现比特的全局重组。方法 首先利用Tent混沌映射生成一个伪随机序列,然后利用生成的伪随机序列对比特明文图像进行整行以及整列的置乱,将置乱后的比特像素矩阵分块分别进行Henon映射的置乱,最后经过扩散操作得到最后的密文图像。结果 加密后明文图像的像素值的分布由不均匀变成了均匀分布,明文图像的各像素间的相关性被打破,使得原图没有了统计特性,像素变化率（NPCR）以及归一化平均变化强度（UACI）皆接近理想值,算法能够抵抗穷举攻击和差分攻击,并且在能保证加密安全的同时能有较低计算复杂度。结论 本文所提出的图像加密算法具有加密后像素相关性低、密钥空间大,以及对明文图像和密钥高度敏感等特点,本文算法在进行比特级的置乱时,又加入了与明文相关的特性,增强了加密算法的明文敏感性,同时也加强了加密算法的扩散性,可有效地保障密文图像的安全。     

一种基于混沌加密的自适应图像水印方法

针对数字水印所要求的安全性、鲁棒性和隐蔽性等特性,提出了一种使用二维混沌加密和人类视觉模型的小波域数字图像水印技术。研究实现了对有意义水印灰度图像的二维Logistic混沌映射加密算法,并结合人类视觉模型,计算加密二值水印的分块嵌入强度,自适应地完成水印在载体图像的小波分解系数中的嵌入和提取过程。实验结果表明,所实现的加密和水印嵌入算法计算量小,能承受常规的数字图像处理,具有良好的数字水印特性。     

双混沌映射的图像加密技术

为了提高图像加密算法的安全性和高效性,提出了一种分段Logistic混沌映射与Cat映射相结合的双混沌系统。首先由改进后的Logistic映射确定选用哪种映射进行迭代,从而确定混沌密钥,最后对算法的安全性进行分析。实验结果表明,该算法的密钥空间较大,并具有较高的初值敏感性和抗攻击能力,是一种新的有效的图像加密算法。     

基于混沌系统的DNA图像加密算法

为了解决数字图像加密算法复杂度高、安全性较差的问题,提出一种基于混沌系统的DNA融合图像加密算法。首先利用Baker变换对图像进行置乱以读取DNA序列;再由Logistic混沌映射产生混沌序列,从而对DNA序列进行混沌加密。该算法对初值具有很好的敏感性,抗统计、抗差分攻击能力强。仿真结果表明:所提算法不仅实现简单,而且加密效果好,安全性高。     

基于混沌映射的自适应图像加密算法

为了提高图像加密算法的鲁棒性,提出了一种新的自适应图像加密算法。首先,把任意大小的灰度或彩色图像分成2×2子块;然后,用左上角子块的像素灰度值和Chebyshev混沌映射构造与右上角子块等大的矩阵,用该矩阵对右上角子块进行像素灰度值替换;最后,按顺时针对每个子块进行加密,直到左上角子块加密完毕。该算法不依赖于图像的大小,而且适用于灰度图像和彩色图像,因而有很强的鲁棒性。同时灰度值扩散机制的引入使得该算法具有良好的扩散性和扰乱性。     

Image encryption based on a combination of multiple chaotic maps

Recent years have seen a rapid evolution of digital communications and an immense use of image transmissions over unsecured links. More specifically, some domains require the exchange of images depicting sensitive information, such as fingerprints, medical records and government or military satellite images. This creates a major challenge for researchers to come up with efficient and effective image encryption schemes. On the other hand, chaotic maps have proven suitable for such applications. This is because they exhibit characteristics such as ergodicity and sensitivity to control parameters and initial conditions. In this paper, an image encryption confusion-diffusion technique is proposed. First, the image pixels are disarranged resulting in a shuffled one which is then diffused through XORing its pixels with a secret key. This key is generated from a combination of different chaotic maps. Performance of the proposed scheme is evaluated utilizing various metrics. The proposed scheme is shown to be robust against differential attacks and resistant to statistical attacks. Its running time is very small which guarantees its efficiency and suitability for real time applications.