A visually secure multiple image encryption using chaotic map and compressive sensing is proposed. The existing image encryption algorithms transform a secret image into a random noise like cipher image which can lead to cryptanalysis by an intruder. In the proposed method, compressive sampling is done using a chaos based, key controlled measurement matrix. An image dependent key generation scheme is used to generate the parameters of the chaotic map. The secret images are transformed into wavelet coefficients, and scrambled along a zigzag path, so that the high correlation among them can be reduced and thereby provide increased security level. The sparse coefficients are measured using the chaotic map-based measurement matrix, whose initial parameters are obtained from the keys generated. Then the reduced measurements are embedded into the sub-bands of the wavelet transformed cover image. Therefore, the proposed algorithm is highly sensitive to the secret images and can effectively withstand known-plaintext and chosen-plaintext attacks. Additionally, the cipher image and the secret images are of same size and do not require additional transmission bandwidth and storage space.
相似文献In order to improve the key space of color image encryption algorithm, the sensitivity to the contents of plain images, the robustness against various types of known attacks, and to achieve the tamper location analysis, a novel color image encryption algorithm based on image hashing, six-dimensional (6D) hyperchaotic and dynamic DNA coding is proposed. Firstly, the color image is pre-processed and the hash sequence is extracted by image hashing algorithm which is used as the initial value and control parameter of chaotic system. Secondly, three color channels of the color image RGB are synthesized into a two-dimensional matrix and the pixels replacement are performed by using the improved two-dimensional chaotic map. Finally, a 6D hyperchaotic system is used to generate random sequences for DNA dynamic coding and arithmetic operations of color images, the encrypted image is obtained. The experimental results show that, compared with the existing methods, the proposed algorithm has a large enough key space, better plain-image sensitivity, better statistical and differential characteristics, as well as can resistant various forms of attacks such as noise and cropping, and the tampering image can be tamper-located analyzed, which has good security and strong robustness.
相似文献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.
相似文献In this digital era, a huge amount of digital data is being generated, transmitted, and stored over the network. Images are widely searched, shared and uploaded which make them more vulnerable to the attackers. Therefore, image encryption has become the most widespread form of secure image communication. In recent past, a range of chaotic encryption schemes have been proposed for image encryption which suffers from low key space and high computational overhead. In this paper, the authors have proposed a secure image encryption technique based on 2D Baker’s map. In the proposed scheme a plain image is permuted first, based on a sequence of pseudo random number generated by 2D Baker’s map followed by diffusion process based on XORing. The strength of the proposed scheme is analyzed using the most well-known security test measures like NPCR, MSE, PSNR, UACI, correlation coefficient, Entropy etc. and the results demonstrate that the proposed scheme is resistive to various types of known attacks. The scheme runs on comparatively low computational overhead. Further, the results are compared with existing schemes.
相似文献Currently, data security is a challenging task in any open source data transmission network. Basically, in most of the networks, images are used, hence security of images is a major challenging task. This paper proposes a combined hyper-chaos and chaos based encryption technique to secure images. In the method, one-round of diffusion and multi-stage bit-plane permutation operations are performed to obtain the better encryption results. The advantages of this scheme are that in one-round encryption operation, the proposed scheme can be realized easily and also confused largely. Apart from that the algorithm is simple as it uses simpler mathematical computations while attaining higher security such as higher key space, higher number of pixel changing rate, higher unified average changing intensity, and better correlation coefficient results. Moreover, hash based keys are used to resist the algorithm against chosen-plaintext and known-plaintext attacks. The security analysis and computer simulations show the good encryption results of the proposed scheme and strong resistivity to the widely used common attacks.
相似文献In the digital transparent world, share the secret messages are challenged one. Visual cryptography (VC) is safer method for information transfer without any distraction by hackers. It is giving more security to the information sharing through digital form. This method hides the messages into images. So intruder cannot understand the distorted image and the data communication become secured. Through VC method number of shares has been generated from the original images. So here each RGB pixel shares are separately created by Visual Secret Share (VSS) scheme. The created multiple shares of the secret images are encrypted and decrypted with RSA algorithm. In the encryption process the multiplication technique is used for key generation process and public key is used for encryption process and private key is used for decryption process. Secret image’s quality has been compared through the Peak Signal to Noise Ratio (PSNR) and Mean Square Error (MSE) values. The experimental result of decrypted image PSNR value is 156.32 and MSE value is 0.5031. The Number of Changing Pixel Rate (NPCR) and Unified Averaged Changed Intensity (UACI) values are compared for the secure level of the secret image. The result of decrypted image NPCR value is 69.44 and UACI value is 13.88. Finally, the experiment result shows that the proposed method is giving more security and quality of secret image sharing and also execution time is faster than existing method.
相似文献In order to obtain a more secure and effective image encryption scheme, a color image encryption scheme based on Fisher-Yates scrambling algorithm and chaos theory is proposed. First, the (secure hash algorithm) SHA-384 is used to generate the key by combining the plaintext image and the encrypted time point. Then, three groups of chaotic sequences are obtained by iterating the three-dimensional Chen chaotic system, and three groups of pseudo-random sequences are obtained by processing with the key. The first group of pseudo-random sequences combined with the Fisher’s algorithm for image pixel position scrambling. A new pixel value substitution method is proposed using the second group of sequences to control each pixel value substitution of the image. The last group generated the matrix after pixel substitution was used for diffusion transformation to obtain the final encrypted image. The test results show that the scheme has broad application prospects.
相似文献We propose a secure image encryption method using the combination of spatial surface chaotic system(SSCS) and the improved AES algorithm structure. In this scheme, the key of cryptosystem is obtained from the SSCS, this system has better encryption characteristics and its model structure fits the image exactly, and it is designed for image cryptosystems contrasted with the existing a lot of low-dimensional chaotic maps and couple map lattices. The plain image is encrypted with the improved AES algorithm and by performing each round encryption, the key is generated by SSCS in each round, an improved permutation algorithm(IPA) and a reverse diffusion have been presented. The proposed scheme not only improves the efficiency because of the same key stream is shared, but also increases the diffusion effect which can resist differential attack. The presented scheme provides huge key space to deal with the brute-force attacks using the round keys obtained by SSCS, and also very sensitive to initial values of SSCS and plain image. The results of simulation analysis and performance evaluation show that the presented cryptosystem provides strong security performance and may be used as a candidate for real-time implementations.
相似文献This paper presents a novel color image encryption approach. The proposed approach utilizes the basic concepts of DNA cryptography along with Lorenz and Rossler chaotic system and 2D logistic map. The proposed approach encrypts RGB images using DNA cryptography techniques. In diffusion phase, at pixel level Lorenz and Rossler chaotic system is used to encrypt the three channels of test images. Afterwards, at bit level 2D logistic map is used for performing bitwise chaotic ponytail process on these diffused Red, Green, and Blue channels in confusion phase. Simulation of the proposed approach on test images reveals that the color images have been encrypted very efficiently.
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