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Sample records for image encryption algorithm

  1. Wavelet Image Encryption Algorithm Based on AES

    2002-01-01

    Traditional encryption techniques have some limits for multimedia information, especially image and video, which are considered only to be common data. In this paper, we propose a wavelet-based image encryption algorithm based on the Advanced Encryption Standard, which encrypts only those low frequency coefficients of image wavelet decomposition. The experimental results are satisfactory.

  2. Cryptanalysis of an Image Scrambling Encryption Algorithm

    Li, Chengqing; Lin, Dongdong

    2016-01-01

    Position scrambling (permutation) is widely used in multimedia encryption schemes and some international encryption standards, like DES and AES. This paper re-evaluated security of a typical image scrambling encryption algorithm (ISEA). Using the internal correlation remaining in the cipher-image, we can disclose some important visual information of the corresponding plain-image under the scenario of ciphertext-only attack. Furthermore, we found the real \\textit{scrambling domain}, position s...

  3. Image Encryption Using a Lightweight Stream Encryption Algorithm

    Saeed Bahrami

    2012-01-01

    Full Text Available Security of the multimedia data including image and video is one of the basic requirements for the telecommunications and computer networks. In this paper, we consider a simple and lightweight stream encryption algorithm for image encryption, and a series of tests are performed to confirm suitability of the described encryption algorithm. These tests include visual test, histogram analysis, information entropy, encryption quality, correlation analysis, differential analysis, and performance analysis. Based on this analysis, it can be concluded that the present algorithm in comparison to A5/1 and W7 stream ciphers has the same security level, is better in terms of the speed of performance, and is used for real-time applications.

  4. Image Encryption on Mobile Phone Using Super Encryption Algorithm

    Catur Iswahyudi

    2012-08-01

    Full Text Available This study aims to obtain the digital image encryption algorithm with a simple but secure process, fast and efficient computing resources. The algorithms developed in this study were super-encryption algorithm that combines two of cipher called Playfair cipher and the Vigenere cipher. To improve security, a keystream generator was used to randomize the order of the next key in Vigenere cipher. In order to evaluate performance, the proposed algorithm was measured through a series of tests. These tests were implemented with Matlab included visual test and histogram analysis, information entropy, encryption quality, correlation analysis, and also time analysis. The test results show that cipher  image looks visually random.The image histogram of the plain image and cipher image also seen a significant difference between the two of them. Testing was also performed on mobile phones with Symbian and BADA operating system based on Java Micro Edition Programming. Trial results show that the algorithm was require less computational resources; with average time for image encryption is 3.76 seconds, and the average time  for image decryption is 0.97 seconds. The new proposed image encryption scheme has satisfactory security which makes it a potential candidate for encryption of image data.   Keywords:  Image encryption, Vigenere cipher, Playfair cipher, Security test

  5. Stegano-Crypto Hiding Encrypted Data in Encrypted Image Using Advanced Encryption Standard and Lossy Algorithm

    Ari Shawakat Tahir

    2015-01-01

    The Steganography is an art and science of hiding information by embedding messages within other, seemingly harmless messages and lots of researches are working in it. Proposed system is using AES Algorithm and Lossy technique to overcome the limitation of previous work and increasing the process’s speed. The sender uses AES Algorithm to encrypt message and image, then using LSB technique to hide encrypted data in encrypted message. The receive get the original data using the keys that had be...

  6. ALGORITHM FOR IMAGE MIXING AND ENCRYPTION

    Ayman M. Abdalla

    2013-04-01

    Full Text Available This new algorithm mixes two or more images of different types and sizes by employing a shuffling procedure combined with S-box substitution to perform lossless image encryption. This combines stream cipher with block cipher, on the byte level, in mixing the images. When this algorithm was implemented, empirical analysis using test images of different types and sizes showed that it is effective and resistant to attacks.

  7. Stegano-Crypto Hiding Encrypted Data in Encrypted Image Using Advanced Encryption Standard and Lossy Algorithm

    Ari Shawakat Tahir

    2015-12-01

    Full Text Available The Steganography is an art and science of hiding information by embedding messages within other, seemingly harmless messages and lots of researches are working in it. Proposed system is using AES Algorithm and Lossy technique to overcome the limitation of previous work and increasing the process’s speed. The sender uses AES Algorithm to encrypt message and image, then using LSB technique to hide encrypted data in encrypted message. The receive get the original data using the keys that had been used in encryption process. The proposed system has been implemented in NetBeans 7.3 software uses image and data in different size to find the system’s speed.

  8. Quantum Image Encryption Algorithm Based on Quantum Image XOR Operations

    Gong, Li-Hua; He, Xiang-Tao; Cheng, Shan; Hua, Tian-Xiang; Zhou, Nan-Run

    2016-07-01

    A novel encryption algorithm for quantum images based on quantum image XOR operations is designed. The quantum image XOR operations are designed by using the hyper-chaotic sequences generated with the Chen's hyper-chaotic system to control the control-NOT operation, which is used to encode gray-level information. The initial conditions of the Chen's hyper-chaotic system are the keys, which guarantee the security of the proposed quantum image encryption algorithm. Numerical simulations and theoretical analyses demonstrate that the proposed quantum image encryption algorithm has larger key space, higher key sensitivity, stronger resistance of statistical analysis and lower computational complexity than its classical counterparts.

  9. Meteosat Images Encryption based on AES and RSA Algorithms

    Boukhatem Mohammed Belkaid

    2015-06-01

    Full Text Available Satellite image Security is playing a vital role in the field of communication system and Internet. This work is interested in securing transmission of Meteosat images on the Internet, in public or local networks. To enhance the security of Meteosat transmission in network communication, a hybrid encryption algorithm based on Advanced Encryption Standard (AES and Rivest Shamir Adleman (RSA algorithms is proposed. AES algorithm is used for data transmission because of its higher efficiency in block encryption and RSA algorithm is used for the encryption of the key of the AES because of its management advantages in key cipher. Our encryption system generates a unique password every new session of encryption. Cryptanalysis and various experiments have been carried out and the results were reported in this paper, which demonstrate the feasibility and flexibility of the proposed scheme.

  10. Digital Image Encryption Algorithm Design Based on Genetic Hyperchaos

    Wang, Jian

    2016-01-01

    In view of the present chaotic image encryption algorithm based on scrambling (diffusion is vulnerable to choosing plaintext (ciphertext) attack in the process of pixel position scrambling), we put forward a image encryption algorithm based on genetic super chaotic system. The algorithm, by introducing clear feedback to the process of scrambling, makes the scrambling effect related to the initial chaos sequence and the clear text itself; it has realized the image features and the organic fusi...

  11. Chaos-Based Image Encryption Algorithm Using Decomposition

    Xiuli Song

    2013-07-01

    Full Text Available The proposed chaos-based image encryption algorithm consists of four stages: decomposition, shuffle, diffusion and combination. Decomposition is that an original image is decomposed to components according to some rule. The purpose of the shuffle is to mask original organization of the pixels of the image, and the diffusion is to change their values. Combination is not necessary in the sender. To improve the efficiency, the parallel architecture is taken to process the shuffle and diffusion. To enhance the security of the algorithm, firstly, a permutation of the labels is designed. Secondly, two Logistic maps are used in diffusion stage to encrypt the components. One map encrypts the odd rows of the component and another map encrypts the even rows. Experiment results and security analysis demonstrate that the encryption algorithm not only is robust and flexible, but also can withstand common attacks such as statistical attacks and differential attacks.

  12. Image Encryption Algorithm Based on Chaotic Economic Model

    S. S. Askar

    2015-01-01

    Full Text Available In literature, chaotic economic systems have got much attention because of their complex dynamic behaviors such as bifurcation and chaos. Recently, a few researches on the usage of these systems in cryptographic algorithms have been conducted. In this paper, a new image encryption algorithm based on a chaotic economic map is proposed. An implementation of the proposed algorithm on a plain image based on the chaotic map is performed. The obtained results show that the proposed algorithm can successfully encrypt and decrypt the images with the same security keys. The security analysis is encouraging and shows that the encrypted images have good information entropy and very low correlation coefficients and the distribution of the gray values of the encrypted image has random-like behavior.

  13. Image encryption a communication perspective

    Abd El-Samie, Fathi E; Elashry, Ibrahim F; Shahieen, Mai H; Faragallah, Osama S; El-Rabaie, El-Sayed M; Alshebeili, Saleh A

    2013-01-01

    Presenting encryption algorithms with diverse characteristics, Image Encryption: A Communication Perspective examines image encryption algorithms for the purpose of secure wireless communication. It considers two directions for image encryption: permutation-based approaches encryption and substitution-based approaches.Covering the spectrum of image encryption principles and techniques, the book compares image encryption with permutation- and diffusion-based approaches. It explores number theory-based encryption algorithms such as the Data Encryption Standard, the Advanced Encryption Standard,

  14. A Novel Image Encryption Algorithm Based on DNA Subsequence Operation

    Zhang, Qiang; Xue, Xianglian; Wei, Xiaopeng

    2012-01-01

    We present a novel image encryption algorithm based on DNA subsequence operation. Different from the traditional DNA encryption methods, our algorithm does not use complex biological operation but just uses the idea of DNA subsequence operations (such as elongation operation, truncation operation, deletion operation, etc.) combining with the logistic chaotic map to scramble the location and the value of pixel points from the image. The experimental results and security analysis show that the proposed algorithm is easy to be implemented, can get good encryption effect, has a wide secret key's space, strong sensitivity to secret key, and has the abilities of resisting exhaustive attack and statistic attack. PMID:23093912

  15. Design and Implementation of Image Encryption Algorithm Using Chaos

    Sandhya Rani M.H.

    2014-06-01

    Full Text Available Images are widely used in diverse areas such as medical, military, science, engineering, art, advertising, entertainment, education as well as training, increasing the use of digital techniques for transmitting and storing images. So maintaining the confidentiality and integrity of images has become a major concern. This makes encryption necessary. The pixel values of neighbouring pixels in a plain image are strongly correlated. The proposed algorithm breaks this correlation increasing the entropy. Correlation is reduced by changing the pixel position this which is called confusion. Histogram is equalized by changing the pixel value this which is called diffusion. The proposed method of encryption algorithm is based on chaos theory. The plain-image is divided into blocks and then performs three levels of shuffling using different chaotic maps. In the first level the pixels within the block are shuffled. In the second level the blocks are shuffled and in the third level all the pixels in an image are shuffled. Finally the shuffled image is diffused using a chaotic sequence generated using symmetric keys, to produce the ciphered image for transmission. The experimental result demonstrates that the proposed algorithm can be used successfully to encrypt/decrypt the images with the secret keys. The analysis of the algorithm also shows that the algorithm gives larger key space and a high key sensitivity. The encrypted image has good encryption effect, information entropy and low correlation coefficient.

  16. Digital Image Encryption Algorithm Design Based on Genetic Hyperchaos

    Jian Wang

    2016-01-01

    Full Text Available In view of the present chaotic image encryption algorithm based on scrambling (diffusion is vulnerable to choosing plaintext (ciphertext attack in the process of pixel position scrambling, we put forward a image encryption algorithm based on genetic super chaotic system. The algorithm, by introducing clear feedback to the process of scrambling, makes the scrambling effect related to the initial chaos sequence and the clear text itself; it has realized the image features and the organic fusion of encryption algorithm. By introduction in the process of diffusion to encrypt plaintext feedback mechanism, it improves sensitivity of plaintext, algorithm selection plaintext, and ciphertext attack resistance. At the same time, it also makes full use of the characteristics of image information. Finally, experimental simulation and theoretical analysis show that our proposed algorithm can not only effectively resist plaintext (ciphertext attack, statistical attack, and information entropy attack but also effectively improve the efficiency of image encryption, which is a relatively secure and effective way of image communication.

  17. The Research of Image Encryption Algorithm Based on Chaos Cellular Automata

    Shuiping Zhang; Huijune Luo

    2012-01-01

    The Research presents an image encryption algorithm which bases on chaotic cellular automata. This algorithm makes use of features that extreme sensitivity of chaotic system to initial conditions, the cellular automaton with a high degree of parallel processing. The encryption algorithm uses two-dimensional chaotic system to Encrypt image, Then establish a cellular automaton model on the initial encrypted image. Encryption key of this algorithm is made up of the initial value by the two-dimen...

  18. Image Encryption Algorithm Based on Chaotic Economic Model

    S. S. Askar; Karawia, A. A.; Ahmad Alshamrani

    2015-01-01

    In literature, chaotic economic systems have got much attention because of their complex dynamic behaviors such as bifurcation and chaos. Recently, a few researches on the usage of these systems in cryptographic algorithms have been conducted. In this paper, a new image encryption algorithm based on a chaotic economic map is proposed. An implementation of the proposed algorithm on a plain image based on the chaotic map is performed. The obtained results show that the proposed algorithm can su...

  19. An Image Encryption Algorithm Utilizing Julia Sets and Hilbert Curves

    Sun, Yuanyuan; Chen, Lina; Xu, Rudan; Kong, Ruiqing

    2014-01-01

    Image encryption is an important and effective technique to protect image security. In this paper, a novel image encryption algorithm combining Julia sets and Hilbert curves is proposed. The algorithm utilizes Julia sets’ parameters to generate a random sequence as the initial keys and gets the final encryption keys by scrambling the initial keys through the Hilbert curve. The final cipher image is obtained by modulo arithmetic and diffuse operation. In this method, it needs only a few parameters for the key generation, which greatly reduces the storage space. Moreover, because of the Julia sets’ properties, such as infiniteness and chaotic characteristics, the keys have high sensitivity even to a tiny perturbation. The experimental results indicate that the algorithm has large key space, good statistical property, high sensitivity for the keys, and effective resistance to the chosen-plaintext attack. PMID:24404181

  20. Grayscale image encryption algorithm based on chaotic maps

    李昌刚; 韩正之

    2003-01-01

    A new image encryption/decryption algorithm has been designed using discrete chaotic systems as aSP (Substitution and Permutation) network architecture often used in cryptosystems. It is composed of two mainmodules: substitution module and permutation module. Both analyses and numerical results imply that the algo-rithm has the desirable security and efficiency.

  1. Chaotic Image Encryption Algorithm by Correlating Keys with Plaintext

    Zhu Congxu; Sun Kehui

    2012-01-01

    A novel image encryption scheme based on the modified skew tent map was proposed in this paper. In the key generating procedure, the algorithm generates a plaintext-dependent secret keys set. In the encryption process, the diffusion operation with cipher output feedback is introduced. Thus, cipher-irmge is sensitive to both initial keys and plaintext through only one round diffusion operation. The key space is large. As a resuk, the algorithm can effectively resist differential attacks, statistical attacks, brute-force attacks, known plaintext and chosen plaintext attacks. Perforrmnce test and security analysis demonstrates that this algorithm is eficient and reliable, with high potential to be adopted for secure comnmnications.

  2. Integral Imaging Based 3-D Image Encryption Algorithm Combined with Cellular Automata

    Li, X. W.; Kim, D. H.; Cho, S. J.; Kim, S. T.

    2013-01-01

    A novel optical encryption method is proposed in this paper to achieve 3-D image encryption. This proposed encryption algorithm combines the use of computational integral imaging (CII) and linear-complemented maximum- length cellular automata (LC-MLCA) to encrypt a 3D image. In the encryption process, the 2-D elemental image array (EIA) recorded by light rays of the 3-D image are mapped inversely through the lenslet array according the ray tracing theory. Next, the 2-D EIA is encrypted by LC-...

  3. Design and Implementation of Image Encryption Algorithm Using Chaos

    Sandhya Rani M.H.; K.L. Sudha

    2014-01-01

    Images are widely used in diverse areas such as medical, military, science, engineering, art, advertising, entertainment, education as well as training, increasing the use of digital techniques for transmitting and storing images. So maintaining the confidentiality and integrity of images has become a major concern. This makes encryption necessary. The pixel values of neighbouring pixels in a plain image are strongly correlated. The proposed algorithm breaks this correlation increasing the en...

  4. Chaos-Based Image Encryption Algorithm Using Decomposition

    Xiuli Song; Hongyao Deng

    2013-01-01

    The proposed chaos-based image encryption algorithm consists of four stages: decomposition, shuffle, diffusion and combination. Decomposition is that an original image is decomposed to components according to some rule. The purpose of the shuffle is to mask original organization of the pixels of the image, and the diffusion is to change their values. Combination is not necessary in the sender. To improve the efficiency, the parallel architecture is taken to process the shuffle and diffusion. ...

  5. An Uncompressed Image Encryption Algorithm Based on DNA Sequences

    Shima Ramesh Maniyath

    2011-07-01

    Full Text Available The rapid growth of the Internet and digitized content made image and video distribution simpler. Hence the need for image and video data protection is on the rise. In this paper, we propose a secure and computationally feasible image and video encryption/decryption algorithm based on DNA sequences. The main purpose of this algorithm is to reduce the big image encryption time. This algorithm is implemented by using the natural DNA sequences as main keys. The first part is the process of pixel scrambling. The original image is confused in the light of the scrambling sequence which is generated by the DNA sequence. The second part is the process of pixel replacement. The pixel gray values of the new image and the one of the three encryption templates generated by the other DNA sequence are XORed bit-by-bit in turn. The main scope of this paper is to propose an extension of this algorithm to videos and making it secure using modern Biological technology. A security analysis for the proposed system is performed and presented.

  6. A chaos-based image encryption algorithm using alternate structure

    ZHANG YiWei; WANG YuMin; SHEN XuBang

    2007-01-01

    Combined with two chaotic maps, a novel alternate structure is applied to image cryptosystem. In proposed algorithm, a general cat-map is used for permutation and diffusion, as well as the OCML (one-way coupled map lattice), which is applied for substitution. These two methods are operated alternately in every round of encryption process, where two subkeys employed in different chaotic maps are generated through the masterkey spreading. Decryption has the same structure with the encryption algorithm, but the masterkey in each round should be reversely ordered in decryption. The cryptanalysis shows that the proposed algorithm bears good immunities to many forms of attacks. Moreover, the algorithm features high execution speed and compact program, which is suitable for various software and hardware applications.

  7. An Improved Piecewise Linear Chaotic Map Based Image Encryption Algorithm

    Hu, Yuping; Wang, Zhijian

    2014-01-01

    An image encryption algorithm based on improved piecewise linear chaotic map (MPWLCM) model was proposed. The algorithm uses the MPWLCM to permute and diffuse plain image simultaneously. Due to the sensitivity to initial key values, system parameters, and ergodicity in chaotic system, two pseudorandom sequences are designed and used in the processes of permutation and diffusion. The order of processing pixels is not in accordance with the index of pixels, but it is from beginning or end alternately. The cipher feedback was introduced in diffusion process. Test results and security analysis show that not only the scheme can achieve good encryption results but also its key space is large enough to resist against brute attack. PMID:24592159

  8. Double color image encryption using iterative phase retrieval algorithm in quaternion gyrator domain

    Shao, Zhuhong; Shu, Huazhong; Wu, Jiasong; Dong, Zhifang; Coatrieux, Gouenou; Coatrieux, Jean-Louis

    2014-01-01

    International audience This paper describes a novel algorithm to encrypt double color images into a single undistinguishable image in quaternion gyrator domain. By using an iterative phase retrieval algorithm, the phase masks used for encryption are obtained. Subsequently, the encrypted image is generated via cascaded quaternion gyrator transforms with different rotation angles. The parameters in quaternion gyrator transforms and phases serve as encryption keys. By knowing these keys, the ...

  9. Integral Imaging Based 3-D Image Encryption Algorithm Combined with Cellular Automata

    X. W. Li

    2013-08-01

    Full Text Available A novel optical encryption method is proposed in this paper to achieve 3-D image encryption. This proposed encryption algorithm combines the use of computational integral imaging (CII and linear-complemented maximum- length cellular automata (LC-MLCA to encrypt a 3D image. In the encryption process, the 2-D elemental image array (EIA recorded by light rays of the 3-D image are mapped inversely through the lenslet array according the ray tracing theory. Next, the 2-D EIA is encrypted by LC-MLCA algorithm. When decrypting the encrypted image, the 2-D EIA is recovered by the LC-MLCA. Using the computational integral imaging reconstruction (CIIR technique and a 3-D object is subsequently reconstructed on the output plane from the 2-D recovered EIA. Because the 2-D EIA is composed of a number of elemental images having their own perspectives of a 3-D image, even if the encrypted image is seriously harmed, the 3-D image can be successfully reconstructed only with partial data. To verify the usefulness of the proposed algorithm, we perform computational experiments and present the experimental results for various attacks. The experiments demonstrate that the proposed encryption method is valid and exhibits strong robustness and security.

  10. Double color image encryption using iterative phase retrieval algorithm in quaternion gyrator domain.

    Shao, Zhuhong; Shu, Huazhong; Wu, Jiasong; Dong, Zhifang; Coatrieux, Gouenou; Coatrieux, Jean Louis

    2014-03-10

    This paper describes a novel algorithm to encrypt double color images into a single undistinguishable image in quaternion gyrator domain. By using an iterative phase retrieval algorithm, the phase masks used for encryption are obtained. Subsequently, the encrypted image is generated via cascaded quaternion gyrator transforms with different rotation angles. The parameters in quaternion gyrator transforms and phases serve as encryption keys. By knowing these keys, the original color images can be fully restituted. Numerical simulations have demonstrated the validity of the proposed encryption system as well as its robustness against loss of data and additive Gaussian noise. PMID:24663832

  11. An improved image encryption algorithm based on chaotic maps

    Xu Shu-Jiang; Wang Ji-Zhi; Yang Su-Xiang

    2008-01-01

    Recently,two chaotic image encryption schemes have been proposed,in which shuffling the positions and changing the grey values of image pixels are combined.This paper provides the chosen plaintext attack to recover the corresponding plaintext of a given ciphertext.Furthermore,it points out that the two schemes are not sufficiently sensitive to small changes of the plaintext.Based on the given analysis,it proposes an improved algorithm which includes two rounds of substitution and one round of permutation to strengthen the overall performance.

  12. A New Algorithm of Encryption and Decryption of Images Using Chaotic Mapping

    Musheer Ahmad

    2010-01-01

    Full Text Available The combination of chaotic theory and cryptography forms an important field of information security. In the past decade, chaos based image encryption is given much attention in the research of information security and a lot of image encryption algorithms based on chaotic maps have been proposed. Due to some inherent features of images like bulk data capacity and high data redundancy, the encryption of images is different from that of texts; therefore it is difficult to handle them by traditional encryption methods. In this communication, a new image encryption algorithm based on three different chaotic maps is proposed. In the proposed algorithm, the plain-image is first decomposed into 8x8 size blocks and then the block based shuffling of image is carried out using 2D Cat map. Further, the control parameters of shuffling are randomly generated by employing 2D coupled Logistic map. After that the shuffled image is encrypted using chaotic sequence generated by one-dimensional Logistic map. The experimental results show that the proposed algorithm can successfully encrypt/decrypt the images with same secret keys, and the algorithm has good encryption effect, large key space and high sensitivity to a small change in secret keys. Moreover, the simulation analysis also demonstrates that the encrypted images have good information entropy, very low correlation coefficients and the distribution of gray values of an encrypted image has random-like behavior.

  13. A Review and Comparative Study of Block based Symmetric Transformation Algorithm for Image Encryption

    Hiral Rathod; Mahendra Singh Sisodia, Sanjay Kumar Sharma

    2011-01-01

    The primary goal of this paper is to provide knowledge of safety of images which is traveling over internet. Moreover, an image-based data requires more effort during encryption and decryption. In this paper I present some advantages and disadvantages of existing algorithm for encryption and decryption of an image with the same objective. Moreover we are also doing analysis of entropy and correlation between pixels value of various image encryption algorithm. From the analysis we are observin...

  14. A fast image encryption algorithm based on chaotic map

    Liu, Wenhao; Sun, Kehui; Zhu, Congxu

    2016-09-01

    Derived from Sine map and iterative chaotic map with infinite collapse (ICMIC), a new two-dimensional Sine ICMIC modulation map (2D-SIMM) is proposed based on a close-loop modulation coupling (CMC) model, and its chaotic performance is analyzed by means of phase diagram, Lyapunov exponent spectrum and complexity. It shows that this map has good ergodicity, hyperchaotic behavior, large maximum Lyapunov exponent and high complexity. Based on this map, a fast image encryption algorithm is proposed. In this algorithm, the confusion and diffusion processes are combined for one stage. Chaotic shift transform (CST) is proposed to efficiently change the image pixel positions, and the row and column substitutions are applied to scramble the pixel values simultaneously. The simulation and analysis results show that this algorithm has high security, low time complexity, and the abilities of resisting statistical analysis, differential, brute-force, known-plaintext and chosen-plaintext attacks.

  15. Chaos-based image encryption using a hybrid genetic algorithm and a DNA sequence

    Enayatifar, Rasul; Abdullah, Abdul Hanan; Isnin, Ismail Fauzi

    2014-05-01

    The paper studies a recently developed evolutionary-based image encryption algorithm. A novel image encryption algorithm based on a hybrid model of deoxyribonucleic acid (DNA) masking, a genetic algorithm (GA) and a logistic map is proposed. This study uses DNA and logistic map functions to create the number of initial DNA masks and applies GA to determine the best mask for encryption. The significant advantage of this approach is improving the quality of DNA masks to obtain the best mask that is compatible with plain images. The experimental results and computer simulations both confirm that the proposed scheme not only demonstrates excellent encryption but also resists various typical attacks.

  16. A New Algorithm of Encryption and Decryption of Images Using Chaotic Mapping

    Musheer Ahmad; M. Shamsher Alam

    2010-01-01

    The combination of chaotic theory and cryptography forms an important field of information security. In the past decade, chaos based image encryption is given much attention in the research of information security and a lot of image encryption algorithms based on chaotic maps have been proposed. Due to some inherent features of images like bulk data capacity and high data redundancy, the encryption of images is different from that of texts; therefore it is difficult to handle them by traditio...

  17. A new image encryption algorithm based on logistic chaotic map with varying parameter.

    Liu, Lingfeng; Miao, Suoxia

    2016-01-01

    In this paper, we proposed a new image encryption algorithm based on parameter-varied logistic chaotic map and dynamical algorithm. The parameter-varied logistic map can cure the weaknesses of logistic map and resist the phase space reconstruction attack. We use the parameter-varied logistic map to shuffle the plain image, and then use a dynamical algorithm to encrypt the image. We carry out several experiments, including Histogram analysis, information entropy analysis, sensitivity analysis, key space analysis, correlation analysis and computational complexity to evaluate its performances. The experiment results show that this algorithm is with high security and can be competitive for image encryption. PMID:27066326

  18. The Research of Image Encryption Algorithm Based on Chaos Cellular Automata

    Shuiping Zhang

    2012-02-01

    Full Text Available The Research presents an image encryption algorithm which bases on chaotic cellular automata. This algorithm makes use of features that extreme sensitivity of chaotic system to initial conditions, the cellular automaton with a high degree of parallel processing. The encryption algorithm uses two-dimensional chaotic system to Encrypt image, Then establish a cellular automaton model on the initial encrypted image. Encryption key of this algorithm is made up of the initial value by the two-dimensional chaotic systems, parameters, two-dimensional cellular automata local evolution rules f and iterations n. Experimental results shows that the algorithm has features that high efficiency, better security, sensitivity to the key and so on.

  19. A chaos-based image encryption algorithm with variable control parameters

    In recent years, a number of image encryption algorithms based on the permutation-diffusion structure have been proposed. However, the control parameters used in the permutation stage are usually fixed in the whole encryption process, which favors attacks. In this paper, a chaos-based image encryption algorithm with variable control parameters is proposed. The control parameters used in the permutation stage and the keystream employed in the diffusion stage are generated from two chaotic maps related to the plain-image. As a result, the algorithm can effectively resist all known attacks against permutation-diffusion architectures. Theoretical analyses and computer simulations both confirm that the new algorithm possesses high security and fast encryption speed for practical image encryption.

  20. A self-adapting image encryption algorithm based on spatiotemporal chaos and ergodic matrix

    Luo Yu-Ling; Du Ming-Hui

    2013-01-01

    To ensure the security of a digital image,a new self-adapting encryption algorithm based on the spatiotemporal chaos and ergodic matrix is proposed in this paper.First,the plain-image is divided into different blocks of the same size,and each block is sorted in ascending order to obtain the corresponding standard ergodic matrix.Then each block is encrypted by the spatiotemporal chaotic system and shuffled according to the standard ergodic matrix.Finally,all modules are rearranged to acquire the final encrypted image.In particular,the plain-image information is used in the initial conditions of the spatiotemporal chaos and the ergodic matrices,so different plain-images will be encrypted to obtain different cipherimages.Theoretical analysis and simulation results indicate that the performance and security of the proposed encryption scheme can encrypt the image effectively and resist various typical attacks.

  1. A new image encryption algorithm based on logistic chaotic map with varying parameter

    Liu, Lingfeng; Miao, Suoxia

    2016-01-01

    In this paper, we proposed a new image encryption algorithm based on parameter-varied logistic chaotic map and dynamical algorithm. The parameter-varied logistic map can cure the weaknesses of logistic map and resist the phase space reconstruction attack. We use the parameter-varied logistic map to shuffle the plain image, and then use a dynamical algorithm to encrypt the image. We carry out several experiments, including Histogram analysis, information entropy analysis, sensitivity analysis,...

  2. An image joint compression-encryption algorithm based on adaptive arithmetic coding

    Through a series of studies on arithmetic coding and arithmetic encryption, a novel image joint compression-encryption algorithm based on adaptive arithmetic coding is proposed. The contexts produced in the process of image compression are modified by keys in order to achieve image joint compression encryption. Combined with the bit-plane coding technique, the discrete wavelet transform coefficients in different resolutions can be encrypted respectively with different keys, so that the resolution selective encryption is realized to meet different application needs. Zero-tree coding is improved, and adaptive arithmetic coding is introduced. Then, the proposed joint compression-encryption algorithm is simulated. The simulation results show that as long as the parameters are selected appropriately, the compression efficiency of proposed image joint compression-encryption algorithm is basically identical to that of the original image compression algorithm, and the security of the proposed algorithm is better than the joint encryption algorithm based on interval splitting. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  3. A new image encryption algorithm based on the fractional-order hyperchaotic Lorenz system

    Wang Zhen; Huang Xia; Li Yu-Xia; Song Xiao-Na

    2013-01-01

    We propose a new image encryption algorithm on the basis of the fractional-order hyperchaotic Lorenz system.While in the process of generating a key stream,the system parameters and the derivative order are embedded in the proposed algorithm to enhance the security.Such an algorithm is detailed in terms of security analyses,including correlation analysis,information entropy analysis,run statistic analysis,mean-variance gray value analysis,and key sensitivity analysis.The experimental results demonstrate that the proposed image encryption scheme has the advantages of large key space and high security for practical image encryption.

  4. A novel hybrid color image encryption algorithm using two complex chaotic systems

    Wang, Leyuan; Song, Hongjun; Liu, Ping

    2016-02-01

    Based on complex Chen and complex Lorenz systems, a novel color image encryption algorithm is proposed. The larger chaotic ranges and more complex behaviors of complex chaotic systems, which compared with real chaotic systems could additionally enhance the security and enlarge key space of color image encryption. The encryption algorithm is comprised of three step processes. In the permutation process, the pixels of plain image are scrambled via two-dimensional and one-dimensional permutation processes among RGB channels individually. In the diffusion process, the exclusive-or (XOR for short) operation is employed to conceal pixels information. Finally, the mixing RGB channels are used to achieve a multilevel encryption. The security analysis and experimental simulations demonstrate that the proposed algorithm is large enough to resist the brute-force attack and has excellent encryption performance.

  5. A novel bit-level image encryption algorithm based on chaotic maps

    Xu, Lu; Li, Zhi; Li, Jian; Hua, Wei

    2016-03-01

    Recently, a number of chaos-based image encryption algorithms have been proposed at the pixel level, but little research at the bit level has been conducted. This paper presents a novel bit-level image encryption algorithm that is based on piecewise linear chaotic maps (PWLCM). First, the plain image is transformed into two binary sequences of the same size. Second, a new diffusion strategy is introduced to diffuse the two sequences mutually. Then, we swap the binary elements in the two sequences by the control of a chaotic map, which can permute the bits in one bitplane into any other bitplane. The proposed algorithm has excellent encryption performance with only one round. The simulation results and performance analysis show that the proposed algorithm is both secure and reliable for image encryption.

  6. Target Image Classification through Encryption Algorithm Based on the Biological Features

    Zhiwu Chen; Qing E. Wu; Weidong Yang

    2014-01-01

    In order to effectively make biological image classification and identification, this paper studies the biological owned characteristics, gives an encryption algorithm, and presents a biological classification algorithm based on the encryption process. Through studying the composition characteristics of palm, this paper uses the biological classification algorithm to carry out the classification or recognition of palm, improves the accuracy and efficiency of the existing biological classifica...

  7. A Novel Image Encryption using an Integration Technique of Blocks Rotation based on the Magic cube and the AES Algorithm

    Ahmed Bashir Abugharsa; Abd. Samad Bin Hasan Basari; Hamida Mohamed Almangush

    2012-01-01

    In recent years, several encryption algorithms have been proposed to protect digital images from cryptographic attacks. These encryption algorithms typically use a relatively small key space and therefore, provide safe, especially if they are of a dimension. In this paper proposes an encryption algorithm for a new image protection scheme based on the rotation of the faces of a Magic Cube. The original image is divided into six sub-images and these sub-images are divided amongst a number of bl...

  8. Hybrid LWT-SVD Watermarking Optimized Using Metaheuristic Algorithms along with Encryption for Medical Image Security

    Venugopal Reddy .CH

    2015-02-01

    Full Text Available Medical image security provides challenges and opportunities, watermarking and encryption of medical images provides the necessary control over the flow of medical information. In this paper a dual security approach is employed .A medical image is considered as watermark and is watermarked inside a natural image. This approach is to wean way the potential attacker by disguising the medical image as a natural image. To further enhance the security the watermarked image is encrypted using encryption algorithms. In this paper a multi–objective optimization approach optimized using different metaheuristic approaches like Genetic Algorithm (GA, Differential Evolution ( DE and Bacterial Foraging Optimization (BFOA is proposed. Such optimization helps in preserving the structural integrity of the medical images, which is of utmost importance. The water marking is proposed to be implemented using both Lifted Wavelet Transforms (LWT and Singular Value Decomposition (SVD technique. The encryption is done using RSA and AES encryption algorithms. A Graphical User Interface (GUI which enables the user to have ease of operation in loading the image, watermark it, encrypt it and also retrieve the original image whenever necessary is also designed and presented in this paper.

  9. A Novel Image Encryption using an Integration Technique of Blocks Rotation based on the Magic cube and the AES Algorithm

    Ahmed Bashir Abugharsa

    2012-07-01

    Full Text Available In recent years, several encryption algorithms have been proposed to protect digital images from cryptographic attacks. These encryption algorithms typically use a relatively small key space and therefore, provide safe, especially if they are of a dimension. In this paper proposes an encryption algorithm for a new image protection scheme based on the rotation of the faces of a Magic Cube. The original image is divided into six sub-images and these sub-images are divided amongst a number of blocks and attached to the faces of a Magic Cube. The faces are then scrambled using rotation of the Magic Cube. Then the rotated image is fed to the AES algorithm which is applied to the pixels of the image to encrypt the scrambled image. Finally, experimental results and security analysis show that the proposed image encryption scheme not only encrypts the picture to achieve perfect hiding, but the algorithm can also withstand exhaustive, statistical and differential attacks.

  10. Analysis and improvement of a chaos-based image encryption algorithm

    The security of digital image attracts much attention recently. In Guan et al. [Guan Z, Huang F, Guan W. Chaos-based image encryption algorithm. Phys Lett A 2005; 346: 153-7.], a chaos-based image encryption algorithm has been proposed. In this paper, the cause of potential flaws in the original algorithm is analyzed in detail, and then the corresponding enhancement measures are proposed. Both theoretical analysis and computer simulation indicate that the improved algorithm can overcome these flaws and maintain all the merits of the original one.

  11. Security analysis of image encryption based on two-dimensional chaotic maps and improved algorithm

    Feng HUANG; Yong FENG

    2009-01-01

    The article proposes a new algorithm to improve the security of image encryption based on two-dimensional chaotic maps.Chaotic maps are often used in encrypting images.However,the encryption has periodic-ity,no diffusion,and at the same time,the real keys space of encryption are fewer than the theoretical keys space,which consequently results in potential security problems.Thus,this article puts forward several ways to solve the problems including adding diffusion mechanism,changing the design of keys and developing a composite encryption system.It designs an algorithm for the version B of the discretized baker map,which is one of the most prevalent chaotic maps,based on which a new image encryption is proposed to avoid the above problems.The simulation results show that the new encryption algorithm is valid and the result can be applied to other two-dimensional chaotic maps,such as the cat map.

  12. Image encryption using fingerprint as key based on phase retrieval algorithm and public key cryptography

    Zhao, Tieyu; Ran, Qiwen; Yuan, Lin; Chi, Yingying; Ma, Jing

    2015-09-01

    In this paper, a novel image encryption system with fingerprint used as a secret key is proposed based on the phase retrieval algorithm and RSA public key algorithm. In the system, the encryption keys include the fingerprint and the public key of RSA algorithm, while the decryption keys are the fingerprint and the private key of RSA algorithm. If the users share the fingerprint, then the system will meet the basic agreement of asymmetric cryptography. The system is also applicable for the information authentication. The fingerprint as secret key is used in both the encryption and decryption processes so that the receiver can identify the authenticity of the ciphertext by using the fingerprint in decryption process. Finally, the simulation results show the validity of the encryption scheme and the high robustness against attacks based on the phase retrieval technique.

  13. A Novel Image Encryption Algorithm Based on DNA Encoding and Spatiotemporal Chaos

    Chunyan Song

    2015-10-01

    Full Text Available DNA computing based image encryption is a new, promising field. In this paper, we propose a novel image encryption scheme based on DNA encoding and spatiotemporal chaos. In particular, after the plain image is primarily diffused with the bitwise Exclusive-OR operation, the DNA mapping rule is introduced to encode the diffused image. In order to enhance the encryption, the spatiotemporal chaotic system is used to confuse the rows and columns of the DNA encoded image. The experiments demonstrate that the proposed encryption algorithm is of high key sensitivity and large key space, and it can resist brute-force attack, entropy attack, differential attack, chosen-plaintext attack, known-plaintext attack and statistical attack.

  14. Image encryption in the wavelet domain

    Bao, Long; Zhou, Yicong; Chen, C. L. Philip

    2013-05-01

    Most existing image encryption algorithms often transfer the original image into a noise-like image which is an apparent visual sign indicating the presence of an encrypted image. Motivated by the data hiding technologies, this paper proposes a novel concept of image encryption, namely transforming an encrypted original image into another meaningful image which is the final resulting encrypted image and visually the same as the cover image, overcoming the mentioned problem. Using this concept, we introduce a new image encryption algorithm based on the wavelet decomposition. Simulations and security analysis are given to show the excellent performance of the proposed concept and algorithm.

  15. Simultaneous image compression, fusion and encryption algorithm based on compressive sensing and chaos

    Liu, Xingbin; Mei, Wenbo; Du, Huiqian

    2016-05-01

    In this paper, a novel approach based on compressive sensing and chaos is proposed for simultaneously compressing, fusing and encrypting multi-modal images. The sparsely represented source images are firstly measured with the key-controlled pseudo-random measurement matrix constructed using logistic map, which reduces the data to be processed and realizes the initial encryption. Then the obtained measurements are fused by the proposed adaptive weighted fusion rule. The fused measurement is further encrypted into the ciphertext through an iterative procedure including improved random pixel exchanging technique and fractional Fourier transform. The fused image can be reconstructed by decrypting the ciphertext and using a recovery algorithm. The proposed algorithm not only reduces data volume but also simplifies keys, which improves the efficiency of transmitting data and distributing keys. Numerical results demonstrate the feasibility and security of the proposed scheme.

  16. Asymmetric optical image encryption based on an improved amplitude-phase retrieval algorithm

    Wang, Y.; Quan, C.; Tay, C. J.

    2016-03-01

    We propose a new asymmetric optical image encryption scheme based on an improved amplitude-phase retrieval algorithm. Using two random phase masks that serve as public encryption keys, an iterative amplitude and phase retrieval process is employed to encode a primary image into a real-valued ciphertext. The private keys generated in the encryption process are used to perform one-way phase modulations. The decryption process is implemented optically using conventional double random phase encoding architecture. Numerical simulations are presented to demonstrate the feasibility and robustness of the proposed system. The results illustrate that the computing efficiency of the proposed method is improved and the number of iterations required is much less than that of the cryptosystem based on the Yang-Gu algorithm.

  17. Fully phase color image encryption based on joint fractional Fourier transform correlator and phase retrieval algorithm

    Ding Lu; Weimin Jin

    2011-01-01

    A novel fully phase color image encryption/decryption scheme based on joint fractional Fourier transform correlator (JFRTC) and phase retrieval algorithm (PRA) is proposed. The security of the system is enhanced by the fractional order as a new added key. This method takes full advantage of the parallel processing features of the optical system and could optically realize single-channel color image encryption.The system and operation procedures are simplified. The simulation results of a color image indicate that the new method provides efficient solutions with a strong sense of security.%@@ A novel fully phase color image encryption/decryption scheme based on joint fractional Fourier transform correlator (JFRTC) and phase retrieval algorithm (PRA) is proposed. The security of the system is enhanced by the fractional order as a new added key. This method takes full advantage of the parallel processing features of the optical system and could optically realize single-channel color image encryption. The system and operation procedures are simplified. The simulation results of a color image indicate that the new method provides efficient solutions with a strong sense of security.

  18. Simultaneous optical image compression and encryption using error-reduction phase retrieval algorithm

    Liu, Wei; Liu, Zhengjun; Liu, Shutian

    2015-12-01

    We report a simultaneous image compression and encryption scheme based on solving a typical optical inverse problem. The secret images to be processed are multiplexed as the input intensities of a cascaded diffractive optical system. At the output plane, a compressed complex-valued data with a lot fewer measurements can be obtained by utilizing error-reduction phase retrieval algorithm. The magnitude of the output image can serve as the final ciphertext while its phase serves as the decryption key. Therefore the compression and encryption are simultaneously completed without additional encoding and filtering operations. The proposed strategy can be straightforwardly applied to the existing optical security systems that involve diffraction and interference. Numerical simulations are performed to demonstrate the validity and security of the proposal.

  19. A novel algorithm for image encryption based on mixture of chaotic maps

    Behnia, S. [Department of Physics, IAU, Urmia (Iran, Islamic Republic of)], E-mail: s.behnia@iaurmia.ac.ir; Akhshani, A.; Mahmodi, H. [Department of Physics, IAU, Urmia (Iran, Islamic Republic of); Akhavan, A. [Department of Engineering, IAU, Urmia (Iran, Islamic Republic of)

    2008-01-15

    Chaos-based encryption appeared recently in the early 1990s as an original application of nonlinear dynamics in the chaotic regime. In this paper, an implementation of digital image encryption scheme based on the mixture of chaotic systems is reported. The chaotic cryptography technique used in this paper is a symmetric key cryptography. In this algorithm, a typical coupled map was mixed with a one-dimensional chaotic map and used for high degree security image encryption while its speed is acceptable. The proposed algorithm is described in detail, along with its security analysis and implementation. The experimental results based on mixture of chaotic maps approves the effectiveness of the proposed method and the implementation of the algorithm. This mixture application of chaotic maps shows advantages of large key space and high-level security. The ciphertext generated by this method is the same size as the plaintext and is suitable for practical use in the secure transmission of confidential information over the Internet.

  20. Optical image encryption using password key based on phase retrieval algorithm

    Zhao, Tieyu; Ran, Qiwen; Yuan, Lin; Chi, Yingying; Ma, Jing

    2016-04-01

    A novel optical image encryption system is proposed using password key based on phase retrieval algorithm (PRA). In the encryption process, a shared image is taken as a symmetric key and the plaintext is encoded into the phase-only mask based on the iterative PRA. The linear relationship between the plaintext and ciphertext is broken using the password key, which can resist the known plaintext attack. The symmetric key and the retrieved phase are imported into the input plane and Fourier plane of 4f system during the decryption, respectively, so as to obtain the plaintext on the CCD. Finally, we analyse the key space of the password key, and the results show that the proposed scheme can resist a brute force attack due to the flexibility of the password key.

  1. Hybrid LWT-SVD Watermarking Optimized Using Metaheuristic Algorithms along with Encryption for Medical Image Security

    Venugopal Reddy .CH; Siddaiah.P

    2015-01-01

    Medical image security provides challenges and opportunities, watermarking and encryption of medical images provides the necessary control over the flow of medical information. In this paper a dual security approach is employed .A medical image is considered as watermark and is watermarked inside a natural image. This approach is to wean way the potential attacker by disguising the medical image as a natural image. To further enhance the security the watermarked image is encrypted using encry...

  2. Hierarchical multiple binary image encryption based on a chaos and phase retrieval algorithm in the Fresnel domain

    Wang, Zhipeng; Lv, Xiaodong; Wang, Hongjuan; Hou, Chenxia; Gong, Qiong; Qin, Yi

    2016-03-01

    Based on the chaos and phase retrieval algorithm, a hierarchical multiple binary image encryption is proposed. In the encryption process, each plaintext is encrypted into a diffraction intensity pattern by two chaos-generated random phase masks (RPMs). Thereafter, the captured diffraction intensity patterns are partially selected by different binary masks and then combined together to form a single intensity pattern. The combined intensity pattern is saved as ciphertext. For decryption, an iterative phase retrieval algorithm is performed, in which a support constraint in the output plane and a median filtering operation are utilized to achieve a rapid convergence rate without a stagnation problem. The proposed scheme has a simple optical setup and large encryption capacity. In particular, it is well suited for constructing a hierarchical security system. The security and robustness of the proposal are also investigated.

  3. Cryptanalysis on an image block encryption algorithm based on spatiotemporal chaos

    Wang Xing-Yuan; He Guo-Xiang

    2012-01-01

    An image block encryption scheme based on spatiotemporal chaos has been proposed recently.In this paper,we analyse the security weakness of the proposal.The main problem of the original scheme is that the generated keystream remains unchanged for encrypting every image.Based on the flaws,we demonstrate a chosen plaintext attack for revealing the equivalent keys with only 6 pairs of plaintext/ciphertext used.Finally,experimental results show the validity of our attack.

  4. Security Analysis of Image Encryption Based on Gyrator Transform by Searching the Rotation Angle with Improved PSO Algorithm

    Sang, Jun; Zhao, Jun; Xiang, Zhili; Cai, Bin; Xiang, Hong

    2015-01-01

    Gyrator transform has been widely used for image encryption recently. For gyrator transform-based image encryption, the rotation angle used in the gyrator transform is one of the secret keys. In this paper, by analyzing the properties of the gyrator transform, an improved particle swarm optimization (PSO) algorithm was proposed to search the rotation angle in a single gyrator transform. Since the gyrator transform is continuous, it is time-consuming to exhaustedly search the rotation angle, even considering the data precision in a computer. Therefore, a computational intelligence-based search may be an alternative choice. Considering the properties of severe local convergence and obvious global fluctuations of the gyrator transform, an improved PSO algorithm was proposed to be suitable for such situations. The experimental results demonstrated that the proposed improved PSO algorithm can significantly improve the efficiency of searching the rotation angle in a single gyrator transform. Since gyrator transform is the foundation of image encryption in gyrator transform domains, the research on the method of searching the rotation angle in a single gyrator transform is useful for further study on the security of such image encryption algorithms. PMID:26251910

  5. Security Analysis of Image Encryption Based on Gyrator Transform by Searching the Rotation Angle with Improved PSO Algorithm.

    Sang, Jun; Zhao, Jun; Xiang, Zhili; Cai, Bin; Xiang, Hong

    2015-01-01

    Gyrator transform has been widely used for image encryption recently. For gyrator transform-based image encryption, the rotation angle used in the gyrator transform is one of the secret keys. In this paper, by analyzing the properties of the gyrator transform, an improved particle swarm optimization (PSO) algorithm was proposed to search the rotation angle in a single gyrator transform. Since the gyrator transform is continuous, it is time-consuming to exhaustedly search the rotation angle, even considering the data precision in a computer. Therefore, a computational intelligence-based search may be an alternative choice. Considering the properties of severe local convergence and obvious global fluctuations of the gyrator transform, an improved PSO algorithm was proposed to be suitable for such situations. The experimental results demonstrated that the proposed improved PSO algorithm can significantly improve the efficiency of searching the rotation angle in a single gyrator transform. Since gyrator transform is the foundation of image encryption in gyrator transform domains, the research on the method of searching the rotation angle in a single gyrator transform is useful for further study on the security of such image encryption algorithms. PMID:26251910

  6. An Image Encryption and Decryption Algorithm Based on Chaos Sequence%基于混沌序列的图像加密解密算法

    陈永红; 黄席樾

    2003-01-01

    In this paper, an image encryption and decryption algorithm based on chaos sequence is proposed. This algorithm provides low computational complexity, high security and no distortion. Finally, experimental results are satisfactory.

  7. Stream Deniable-Encryption Algorithms

    N.A. Moldovyan

    2016-04-01

    Full Text Available A method for stream deniable encryption of secret message is proposed, which is computationally indistinguishable from the probabilistic encryption of some fake message. The method uses generation of two key streams with some secure block cipher. One of the key streams is generated depending on the secret key and the other one is generated depending on the fake key. The key streams are mixed with the secret and fake data streams so that the output ciphertext looks like the ciphertext produced by some probabilistic encryption algorithm applied to the fake message, while using the fake key. When the receiver or/and sender of the ciphertext are coerced to open the encryption key and the source message, they open the fake key and the fake message. To disclose their lie the coercer should demonstrate possibility of the alternative decryption of the ciphertext, however this is a computationally hard problem.

  8. 3D Chaotic Functions for Image Encryption

    Pawan N. Khade

    2012-05-01

    Full Text Available This paper proposes the chaotic encryption algorithm based on 3D logistic map, 3D Chebyshev map, and 3D, 2D Arnolds cat map for color image encryption. Here the 2D Arnolds cat map is used for image pixel scrambling and 3D Arnolds cat map is used for R, G, and B component substitution. 3D Chebyshev map is used for key generation and 3D logistic map is used for image scrambling. The use of 3D chaotic functions in the encryption algorithm provide more security by using the, shuffling and substitution to the encrypted image. The Chebyshev map is used for public key encryption and distribution of generated private keys.

  9. Multilevel Image Encryption

    S Rakesh; Kaller, Ajitkumar A; Shadakshari, B. C.; Annappa, B.

    2012-01-01

    With the fast evolution of digital data exchange and increased usage of multi media images, it is essential to protect the confidential image data from unauthorized access. In natural images the values and position of the neighbouring pixels are strongly correlated. The method proposed in this paper, breaks this correlation increasing entropy of the position and entropy of pixel values using block shuffling and encryption by chaotic sequence respectively. The plain-image is initially row wise...

  10. Performance study of selective encryption in comparison to full encryption for still visual images

    Osama A.KHASHAN; Abdullah M.ZIN; Elankovan A.SUNDARARAJAN

    2014-01-01

    Securing digital images is becoming an important concern in today’s information security due to the extensive use of secure images that are either transmitted over a network or stored on disks. Image encryption is the most effective way to fulfil confidentiality and protect the privacy of images. Nevertheless, owing to the large size and complex structure of digital images, the computational overhead and processing time needed to carry out full image encryption prove to be limiting factors that inhibit it of being used more heavily in real time. To solve this problem, many recent studies use the selective encryption approach to encrypt significant parts of images with a hope to reduce the encryption overhead. However, it is necessary to realistically evaluate its performance compared to full encryption. In this paper, we study the performance and efficiency of image segmentation methods used in the selective encryption approach, such as edges and face detection methods, in determining the most important parts of visual images. Experiments were performed to analyse the computational results obtained by selective image encryption compared to full image encryption using symmetric encryption algorithms. Experiment results have proven that the selective encryption approach based on edge and face detection can significantly reduce the time of encrypting still visual images as compared to full encryption. Thus, this approach can be considered a good alternative in the implementation of real-time applications that require adequate security levels.

  11. Advanced Steganography Algorithm using Encrypted secret message

    Joyshree Nath

    2011-03-01

    Full Text Available In the present work the authors have introduced a new method for hiding any encrypted secret message inside a cover file. For encrypting secret message the authors have used new algorithm proposed by Nath et al(1. For hiding secret message we have used a method proposed by Nath et al(2. In MSA(1 method we have modified the idea of Play fair method into a new platform where we can encrypt or decrypt any file. We have introduced a new randomization method for generating the randomized key matrix to encrypt plain text file and to decrypt cipher text file. We have also introduced a new algorithm for encrypting the plain text multiple times. Our method is totally dependent on the random text_key which is to be supplied by the user. The maximum length of the text_key can be of 16 characters long and it may contain any character(ASCII code 0 to 255. We have developed an algorithm to calculate the randomization number and the encryption number from the given text_key. The size of the encryption key matrix is 16x16 and the total number of matrices can be formed from 16 x 16 is 256! which is quite large and hence if someone applies the brute force method then he/she has to give trail for 256! times which is quite absurd. Moreover the multiple encryption method makes the system further secured. For hiding secret message in the cover file we have inserted the 8 bits of each character of encrypted message file in 8 consecutive bytes of the cover file. We have introduced password for hiding data in the cover file. We propose that our new method could be most appropriate for hiding any file in any standard cover file such as image, audio, video files. Because the hidden message is encrypted hence it will be almost impossible for the intruder to unhide the actual secret message from the embedded cover file. This method may be the most secured method in digital water marking.

  12. Spatial chaos-based image encryption design

    2009-01-01

    In recent years, the chaos based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques, but the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. In this paper, permutation and sub- stitution methods are incorporated to present a stronger image encryption algorithm. Spatial chaotic maps are used to realize the position permutation, and to confuse the relationship between the ci- pher-image and the plain-image. The experimental results demonstrate that the suggested encryption scheme of image has the advantages of large key space and high security; moreover, the distribution of grey values of the encrypted image has a random-like behavior.

  13. Spatial chaos-based image encryption design

    LIU ShuTang; SUN FuYan

    2009-01-01

    In recent years, the chaos based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques, but the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. In this paper, permutation and sub-stitution methods are incorporated to present a stronger image encryption algorithm. Spatial chaotic maps are used to realize the position permutation, and to confuse the relationship between the ci-pher-image and the plain-image. The experimental results demonstrate that the suggested encryption scheme of image has the advantages of large key space and high security; moreover, the distribution of grey values of the encrypted image has a random-like behavior.

  14. Security enhancement of a phase-truncation based image encryption algorithm.

    Wang, Xiaogang; Zhao, Daomu

    2011-12-20

    The asymmetric cryptosystem, which is based on phase-truncated Fourier transforms (PTFTs), can break the linearity of conventional systems. However, it has been proven to be vulnerable to a specific attack based on iterative Fourier transforms when the two random phase masks are used as public keys to encrypt different plaintexts. An improvement from the asymmetric cryptosystem may be taken by relocating the amplitude values in the output plane. In this paper, two different methods are adopted to realize the amplitude modulation of the output image. The first one is to extend the PTFT-based asymmetrical cryptosystem into the anamorphic fractional Fourier transform domain directly, and the second is to add an amplitude mask in the Fourier plane of the encryption scheme. Some numerical simulations are presented to prove the good performance of the proposed cryptosystems. PMID:22193194

  15. Image encryption using the fractional wavelet transform

    Vilardy, Juan M; Useche, J; Torres, C O; Mattos, L, E-mail: vilardy.juan@unicesar.edu.co [Laboratorio de Optica e Informatica, Universidad Popular del Cesar, Sede balneario Hurtado, Valledupar, Cesar (Colombia)

    2011-01-01

    In this paper a technique for the coding of digital images is developed using Fractional Wavelet Transform (FWT) and random phase masks (RPMs). The digital image to encrypt is transformed with the FWT, after the coefficients resulting from the FWT (Approximation, Details: Horizontal, vertical and diagonal) are multiplied each one by different RPMs (statistically independent) and these latest results is applied an Inverse Wavelet Transform (IWT), obtaining the encrypted digital image. The decryption technique is the same encryption technique in reverse sense. This technique provides immediate advantages security compared to conventional techniques, in this technique the mother wavelet family and fractional orders associated with the FWT are additional keys that make access difficult to information to an unauthorized person (besides the RPMs used), thereby the level of encryption security is extraordinarily increased. In this work the mathematical support for the use of the FWT in the computational algorithm for the encryption is also developed.

  16. Image encryption using the fractional wavelet transform

    In this paper a technique for the coding of digital images is developed using Fractional Wavelet Transform (FWT) and random phase masks (RPMs). The digital image to encrypt is transformed with the FWT, after the coefficients resulting from the FWT (Approximation, Details: Horizontal, vertical and diagonal) are multiplied each one by different RPMs (statistically independent) and these latest results is applied an Inverse Wavelet Transform (IWT), obtaining the encrypted digital image. The decryption technique is the same encryption technique in reverse sense. This technique provides immediate advantages security compared to conventional techniques, in this technique the mother wavelet family and fractional orders associated with the FWT are additional keys that make access difficult to information to an unauthorized person (besides the RPMs used), thereby the level of encryption security is extraordinarily increased. In this work the mathematical support for the use of the FWT in the computational algorithm for the encryption is also developed.

  17. Parallel bidirectional image encryption algorithm based on self-adaptive chaos%自适应混沌的并行双向图像加密方案

    刘祝华

    2014-01-01

    In order to improve the running speed of image encryption algorithm and consider the security of the algorithm, a parallel bidirectional image encryption algorithm based on self-adaptive chaos is proposed. The grouping and parallel encryp-tion for images is executed by this algorithm. Two one-dimensional chaotic maping parameters and original value are disturbed by elements in image groups. The encryption sequence is generated through two chaotic sequences’XOR operation. The bidirec-tional encryption is adopted in the algorithm. Diffusion between groups is implemented by using the last element of every group after forward encryption. The change of the last element is spread to the whole group through reverse encryption. The experimen-tal results show that the algorithm encrypts fast,and has high safety.%为了提高图像加密算法的运行速度,同时兼顾算法的安全性,提出了一种自适应混沌的并行双向图像加密算法。算法对图像进行分组并行加密,用分组内的元素对两个一维混沌映射的参数及初始值进行扰动,并将生成的两个混沌序列相异或得到加密序列。采用正反双向加密,在正向加密后使用分组最后一个元素实现分组间扩散,最后通过反向加密将最后一个元素的变化扩散至整个分组。实验结果表明,算法执行速度快,且安全性高。

  18. 基于混沌序列的数字彩色图像加密算法%Encryption Algorithm for Digital Color Image Based on Chaotic Sequences

    何松林

    2011-01-01

    The new encryption algorithm for digital color image is proposed. The image can be encrypted through encryption matrixes generated with Logistic chaotic sequences to exclusive OR(XOR) color matrixes many times. The R, G and B components of the color image can be treated randomly and encrypted image becomes more uniform. Because the chaotic sequences are extremely sensitive to the parameters and the initial values, even ifthe encryption algorithm is open. Without the right key, the useful information can not be got. The encryption key length is effectively enlarged by using multiple sets of parameter of the branch and initial value as the encryption key. The experiments confirm its validity.%提出用Logistic混沌序列产生多个加密矩阵与基色矩阵进行多次异或的方法,对彩色图像的RGB分量进行随机化处理,使加密后的图像均匀.由于混沌序列对参数和初始值的极端敏感性,即使加密算法被公开,没有正确的密钥也无法得到有用信息.因此采用多组分支参数和初始值作为密钥,使密钥长度有效增加.实验结果证明了该算法是有效的.

  19. Selective image encryption using a spatiotemporal chaotic system.

    Xiang, Tao; Wong, Kwok-wo; Liao, Xiaofeng

    2007-06-01

    A universal selective image encryption algorithm, in which the spatiotemporal chaotic system is utilized, is proposed to encrypt gray-level images. In order to resolve the tradeoff between security and performance, the effectiveness of selective encryption is discussed based on simulation results. The scheme is then extended to encrypt RGB color images. Security analyses for both scenarios show that the proposed schemes achieve high security and efficiency. PMID:17614669

  20. A block image encryption algorithm on coupled map lattice%基于耦合映像格子的分组图像加密算法

    杨杨; 张雪锋; 张雁冰

    2012-01-01

    针对传统的基于混沌的数字图像加密算法存在的抗差分攻击性能较弱、对受损密文图像恢复效果较差的问题,设计出一种基于分组密码和交替迭代结构的数字图像加密算法。在每一轮加密中,采用不同的耦合映像格子来构造S盒,使得算法具有更好的安全性能。实验结果表明,该算法不仅具有较好的加密效果,而且对受损密文图像也能得到较好的恢复效果。%Aimed at the problems that traditional digital image encryption algorithm based on chaos performs weak in anti-differential cryptanalysis and has poor effect on recovery of impaired encryption image,a digital image encryption algorithm based on block cipher and alternating iteration structure is designed,which adopts different CML to form S-box during each round of encryption,bringing better security performance to the algorithm.Experiment results show that the algorithm not only possesses well encryption effect,but also very useful for the recovery of impaired encryption image.

  1. Image encryption using P-Fibonacci transform and decomposition

    Zhou, Yicong; Panetta, Karen; Agaian, Sos; Chen, C. L. Philip

    2012-03-01

    Image encryption is an effective method to protect images or videos by transferring them into unrecognizable formats for different security purposes. To improve the security level of bit-plane decomposition based encryption approaches, this paper introduces a new image encryption algorithm by using a combination of parametric bit-plane decomposition along with bit-plane shuffling and resizing, pixel scrambling and data mapping. The algorithm utilizes the Fibonacci P-code for image bit-plane decomposition and the 2D P-Fibonacci transform for image encryption because they are parameter dependent. Any new or existing method can be used for shuffling the order of the bit-planes. Simulation analysis and comparisons are provided to demonstrate the algorithm's performance for image encryption. Security analysis shows the algorithm's ability against several common attacks. The algorithm can be used to encrypt images, biometrics and videos.

  2. Integration of chaotic sequences uniformly distributedin a new image encryption algorithm

    Nassiba Wafa Abderrahim

    2012-03-01

    Full Text Available In this paper we propose a new chaotic secret key cryptosystem, adapted for image encryption in continuous mode, which is based on the use of tow one-dimensional discrete chaotic systems: Bernoulli map and Tent map. The pseudorandom sequences generated by the two maps are characterized by independence of their states, uniformly distributed, so hear integration provides excellent properties of confusion and diffusion, and an important space for the secret key, because it consists of parameters and initial states of the chaotic maps. The security tests results of our cryptosystem are very satisfactory.

  3. 基于自适应排列的快速图像加密算法%Fast Image Encryption Algorithm Based on Self-adaptive Permutation

    刘梅

    2009-01-01

    现有自适应图像加密算法可以抵抗已知明文攻击,其单轮加密速度很快,但安全性和整体加密速度较低.基于自适应排列提出一种新的快速图像加密算法,在确保加密操作简单高效的前提下,改变加密前后图像的像素分布.实验结果表明,该算法性能优于其他同类算法.%Existing self-adaptive image encryption algorithm is resistant to known plaintext attacks and with high speed of single round eneryption, but its security and speed of whole round encryption is low. This paper proposes a new fast image encryption algorithm based on self-adaptive permutation. This algorithm insures the simpleness and high efficiency of encryption operation, and changes the pixel distribution of encrypted image compared with that of original image. Experimental results show that this algorithm has better performance than other kindred algorithms.

  4. 一种高效的彩色图像加密和解密算法%Efficient Encryption and Decryption Algorithm for Color Image

    彭静玉

    2013-01-01

    分析了基于Arnold变换的加密方案在加密效果及加密效率方面的不足。提出了一种新的彩色图像加密及解密算法。加密过程将像素的物理位置置乱并映射到不同的色彩空间;解密过程提出了一种针对彩色图像的逆变换算法,使解密的时间仅依赖加密的密钥而不依赖变换周期。仿真分析比较了该算法在加密效果及加密效率方面的优势。实验数据表明,该加密算法的加密效果理想,且加密效率较高,是一种简单、可行的彩色图像加密方法。%The deficiencies of encryption scheme based on Arnold transformation is analyzed, and a new encryption/decryption algorithm for color image proposed. The physical locations of pixels are scrambled and mapped to different color spaces in the encryption process. An inverse conversion method for color im-age is suggested in decryption process, thus making the decryption time dependent only on the encryption key instead of on the conversion cycle. Simulation and comparison of the advantages of proposed algorithm in encryption effect and encryption efficiency indicates that the proposed algorithm could improve encryp-tion effect while raising the decryption efficiency, and thus a simple and feasible color image encryption method.

  5. 基于RSA的数字图像加密算法%An Encryption Algorithm for Digital Image Based on RSA System

    杨昔阳; 李志伟

    2009-01-01

    It proposes a novel encryption method for digital image based on an Arnold scrambling transform, a chaos encryption algorithm and RSA encryption system. The parameters of the Arnold transform and chaos encryption algorithm are encrypted by RSA system and stored in LSB of an image to ensure the security in transmission. The example in this paper shows that the proposed method is an efficient way to encrypt a digital image.%提出一种基于RSA公钥、Arnold置乱变换和混沌加密算法相结合的公开密钥数字图像加密体制,利用客户的公钥对Arnold置乱变换和混沌序列初值进行RSA加密,确保了只有合法用户才能获取置乱参数信息并将图像复原.RSA对参数的加密信息隐藏于图像LSB中,无需另外传递密文,运算简单,具有良好的加密与隐藏效果.

  6. Optical image encryption based on multifractional Fourier transforms.

    Zhu, B; Liu, S; Ran, Q

    2000-08-15

    We propose a new image encryption algorithm based on a generalized fractional Fourier transform, to which we refer as a multifractional Fourier transform. We encrypt the input image simply by performing the multifractional Fourier transform with two keys. Numerical simulation results are given to verify the algorithm, and an optical implementation setup is also suggested. PMID:18066153

  7. Image encryption using high-dimension chaotic system

    Sun Fu-Yan; Liu Shu-Tang; Lü Zong-Wang

    2007-01-01

    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 new approach for image encryption based on a highdimensional chaotic map. The new scheme employs the Cat map to shuffle the positions, then to confuse the relationship between the cipher-image and the plain-image using the high-dimensional Lorenz chaotic map preprocessed. The results of experimental, statistical analysis and key space analysis show that the proposed image encryption scheme provides an efficient and secure way for real-time image encryption and transmission.

  8. Experimental optical encryption system based on a single-lens imaging architecture combined with a phase retrieval algorithm

    We propose, and experimentally demonstrate, a single-lens imaging system as a compact encoding architecture by using a hybrid protocol for data processing. The encryption process consists of coherent light illuminating a random phase mask attached to an input image (the data), then the outgoing complex field propagates until reaching a second random phase mask next to a lens: encrypted data is obtained at some output plane after the lens. We demonstrate the feasibility of this proposal, and highlight the advantages of using tridimensional speckle as a secure random carrier instead of a standard ciphertext recording—holographic-based encryption techniques. Moreover, we expose the compact system benefits compared to conventional encrypting architectures in terms of energy loss and tolerance against classical attacks applicable to any linear cryptosystem. Experimental results validate our approach. (paper)

  9. A lossless encryption method for medical images using edge maps.

    Zhou, Yicong; Panetta, Karen; Agaian, Sos

    2009-01-01

    Image encryption is an effective approach for providing security and privacy protection for medical images. This paper introduces a new lossless approach, called EdgeCrypt, to encrypt medical images using the information contained within an edge map. The algorithm can fully protect the selected objects/regions within medical images or the entire medical images. It can also encrypt other types of images such as grayscale images or color images. The algorithm can be used for privacy protection in the real-time medical applications such as wireless medical networking and mobile medical services. PMID:19965008

  10. Securing Images Using Chaotic-based Image Encryption Cryptosystem

    Abdalwhab A. Alkher

    2016-03-01

    Full Text Available Given the rapid evolution in imaging and communication techniques, images become very important data transmitted over public networks type. Therefore, a fast and secure encryption system for high-resolution images is a tremendous demand. In this paper, a novel encryption system is proposed to secure images on the basis of Arnold Catmap. In the First, Arnold cat map system is used to scramble the positions of image pixels. Then, chaotic map is used to generate pseudorandom image for substitution. The statistical analysis was performed on the proposed encryption algorithm demonstrating superior confusion and deployment of its properties, which strongly resist statistical attacks. Coefficients of correlation between adjacent pixels showed that correlation between pixels of the encrypted image has significantly decreased. It is noted that the number of pixels of the image encoded drops significantly which indicates that the proposed system can thwart correlation attacks.

  11. Degradative encryption: An efficient way to protect SPIHT compressed images

    Xiang, Tao; Qu, Jinyu; Yu, Chenyun; Fu, Xinwen

    2012-11-01

    Degradative encryption, a new selective image encryption paradigm, is proposed to encrypt only a small part of image data to make the detail blurred but keep the skeleton discernible. The efficiency is further optimized by combining compression and encryption. A format-compliant degradative encryption algorithm based on set partitioning in hierarchical trees (SPIHT) is then proposed, and the scheme is designed to work in progressive mode for gaining a tradeoff between efficiency and security. Extensive experiments are conducted to evaluate the strength and efficiency of the scheme, and it is found that less than 10% data need to be encrypted for a secure degradation. In security analysis, the scheme is verified to be immune to cryptographic attacks as well as those adversaries utilizing image processing techniques. The scheme can find its wide applications in online try-and-buy service on mobile devices, searchable multimedia encryption in cloud computing, etc.

  12. The Image Encryption Algorithms Research Based on the Improved CCS-PRBG%基于改进CCS-PRBG的图像加密算法研究

    顾理琴; 季秀兰

    2014-01-01

    随着信息技术的高速发展,现有的图像加密算法已经无法满足图像数据加密的需求。本文基于图像加密现状和混沌序列密码技术,在双混沌系统伪随机比特发生器技术基础上,提出了一种基于改进CCS-PRBG的图像加密算法,首先对比特位平面进行分解,再对每个比特位平面进行置乱,然后对每个比特位平面进行流密码加密最后合并加密后的比特位平面得到加密图像。实验结果表明,本文提出的基于改进CCS-PRBG的图像加密算法安全性能良好,值得推广使用。%With the rapid development of modern information technology, the existing image encryption algorithm has been unable to meet the needs of the image data encryption.Based on the current situation of image encryption and chaotic sequence code technology, and on the technology of bit generator of double chaos system pseudo random, this paper puts forward a kind of image encryption algorithm based on improved CCS- PRBG, first it decomposes the bit plane, then scrambles for each bit plane, then it carries out the stream cipher encryption for each bit plane and finally merges them, thus we can get encryption image from the encrypted bit plane.The experimental results show that the proposed image encryption algorithm based on improved CCS-PRBG is good in safety performance, and it is worthy to be popularized.

  13. Double-image encryption based on Yang-Gu mixture amplitude-phase retrieval algorithm and high dimension chaotic system in gyrator domain

    Sui, Liansheng; Liu, Benqing; Wang, Qiang; Li, Ye; Liang, Junli

    2015-11-01

    A double-image encryption scheme is proposed based on Yang-Gu mixture amplitude-phase retrieval algorithm and high dimension chaotic system in gyrator transform domain, in which three chaotic random sequences are generated by using Chen system. First, an enlarged image constituted with two plaintext images is scrambled by using the first two sequences, and then separated into two new interim images. Second, one interim image is converted to the private phase key with the help of the third sequence, which is modulated by a random phase key generated based on logistic map. Based on this private phase key, another interim image is converted to the ciphertext with white noise distribution in the Yang-Gu amplitude-phase retrieval process. In the process of encryption and decryption, the images both in spatial domain and gyrator domain are nonlinear and disorder by using high dimension chaotic system. Moreover, the ciphertext image is only a real-valued function which is more convenient for storing and transmitting, and the security of the proposed encryption scheme is enhanced greatly because of high sensitivity of initial values of Chen system and rotation angle of gyrator transform. Extensive cryptanalysis and simulation results have demonstrated the security, validity and feasibility of the propose encryption scheme.

  14. 基于细胞自动机的安全图像加密算法%Secure Image Encryption Algorithm Based on Cellular Automata

    熊永红; 廖晓峰; 周庆

    2011-01-01

    In order to solve the problems that the cipher image encrypted by encryption algorithm based on the merit of the state attractors of Elementary Cellular Automata(ECA) can still discern part outline of the original image, and the plaintext sensitivity is poor, this paper proposes a secure image encryption algorithm. It employs the method which encrypts every bit plane with period two 2D Cellular Automata(CA), and then uses state attractors to encrypt the image, to achieve the effect that I bit change in the plaintext can be spreaded to the whole cipher image. Simulation results show that the improved algorithm is more sensitive, has larger key space, and easy to implement.%利用初等细胞自动机状态环性质进行加密后的密文图像仍可看出原图像的部分轮廓,且明文敏感性差.由此提出一种安全的图像加密算法,采用周期为2的二维细胞自动机对图像进行位平面加密,再通过状态环加密的方法使明文改变1 bit即可影响整个密文图像.仿真结果表明,改进算法敏感性更高,密钥空间更大,且加密速度较快.

  15. 一种多混沌的彩色图像认证加密算法%A Color Image Authentication Encryption Algorithm Based Multi-chaos

    蒲昌玖

    2013-01-01

    In order to protect color image effectively,a color image encryption scheme based on multiple chaotic maps and authentication is presented.The algorithm generated 128-bit Hash keys by the mathematical operation in the RGB components of the color image,and the Hash key is used as part of the image encryption keys.Then,pixels shuffling and pixels substitution are simultaneous implemented to encrypt the color image using Logistic chaotic system,unified chaotic system and Hash keys.Finally,theoretical analyses and simulated experiment show that the color image encryption algorithm shows advantages of larger key space,higher security,a random distribution characteristics of the pixel value of the encrypted image and the zero correlation of adjacent pixels.%为了实现对彩色图像的有效保护,提出一种基于多混沌系统和图像认证功能的彩色图像加密算法.该算法通过对彩色图像RGB分量的运算生成128位Hash值,并把该Hash值作为部分图像加密的密钥.然后通过Logistic混沌系统、统一混沌系统和Hash值对彩色图像进行像素置乱和替代操作以实现图像加密.最后,理论分析和仿真实验结果表明,该加密算法具有密钥空间大,保密性好,加密图像像素值具有类随机均匀分布特性和相邻像素值的零相关特性.

  16. Improved Cryptanalysis of CMC Chaotic Image Encryption Scheme

    Jiansheng Guo

    2010-12-01

    Full Text Available Recently, chaos has attracted much attention in the field of cryptography. To study the security with a known image of a symmetric image encryption scheme, the attack algorithm of equivalent key is given. We give the known image attacks under different other conditions to obtain the equivalent key. The concrete step and complexity of the attack algorithm is given. So the symmetric image encryption scheme based on 3D chaotic cat maps is not secure.

  17. Image Encryption Algorithm Based on Extended Two-dimensional Cellular Automata%基于扩展型二维CA的图像加密算法

    罗小刚; 李轩; 彭承琳; 侯长军; 霍丹群

    2009-01-01

    根据数字图像的存储特点,提出一种基于扩展型二维元胞自动机的图像加密算法,将二维元胞自动机与图像加密技术结合,利用元胞自动机生成数值范围在0~255区间的二维伪随机数矩阵,截取与图像大小相等的伪随机数矩阵作为密码对图像像素进行加密,解密为加密的逆过程.实验结果表明,该算法能快速产生密码,加密形式简单,具有较好的抗攻击能力,适合对数据量大的数字图像进行加密.%According to the storage characteristics of digital image, an image encryption algorithm based on extended two-dimensional Cellular Automata(CA) is proposed in this paper. It combines the two-dimensional CA with the technology of image encryption, which uses CA to generate a two-dimensional matrix pseudo-random number ranged from 0 to 255 automatically and takes a part of this matrix as the code to enerypt image pixels, and the size of this matrix is the same as the image. The decryption is the converse process of encryption. Experimental results demonstrate this algorithm can generate cryptogram rapidly and has a simple encrypt form as well as a better performance against attacks. It is suitable for encrypting digital images with huge data.

  18. Algoritmi selektivnog šifrovanja - pregled sa ocenom performansi / Selective encryption algorithms: Overview with performance evaluation

    Boriša Ž. Jovanović

    2010-10-01

    Full Text Available Digitalni multimedijalni sadržaj postaje zastupljeniji i sve više se razmenjuje putem računarskih mreža i javnih kanala (satelitske komunikacije, bežične mreže, internet, itd. koji predstavljaju nebezbedne medijume za prenos informacija osetljive sadržine. Sve više na značaju dobijaju mehanizmi kriptološke zaštite slika i video sadržaja. Tradicionalni sistemi kriptografske obrade u sistemima za prenos ovih vrsta informacija garantuju visok stepen sigurnosti, ali i imaju svoje nedostatke - visoku cenu implementacije i znatno kašnjenje u prenosu podataka. Pomenuti nedostaci se prevazilaze primenom algoritama selektivnog šifrovanja. / Digital multimedia content is becoming widely used and increasingly exchanged over computer network and public channels (satelite, wireless networks, Internet, etc. which is unsecured transmission media for ex changing that kind of information. Mechanisms made to encrypt image and video data are becoming more and more significant. Traditional cryptographic techniques can guarantee a high level of security but at the cost of expensive implementation and important transmission delays. These shortcomings can be exceeded using selective encryption algorithms. Introduction In traditional image and video content protection schemes, called fully layered, the whole content is first compressed. Then, the compressed bitstream is entirely encrypted using a standard cipher (DES - Data Encryption Algorithm, IDEA - International Data Encryption Algorithm, AES - Advanced Encryption Algorithm etc.. The specific characteristics of this kind of data, high-transmission rate with limited bandwidth, make standard encryption algorithms inadequate. Another limitation of traditional systems consists of altering the whole bitstream syntax which may disable some codec functionalities on the delivery site coder and decoder on the receiving site. Selective encryption is a new trend in image and video content protection. As its

  19. Performance Study on Image Encryption Schemes

    Shah, Jolly

    2011-01-01

    Image applications have been increasing in recent years.Encryption is used to provide the security needed for image applications. In this paper, we classify various image encryption schemes and analyze them with respect to various parameters like tunability, visual degradation, compression friendliness,format compliance, encryption ratio, speed, and cryptographic security.

  20. Performance Study on Image Encryption Schemes

    Jolly Shah; Vikas Saxena

    2011-01-01

    Image applications have been increasing in recent years. Encryption is used to provide the security needed for image applications. In this paper, we classify various image encryption schemes and analyze them with respect to various parameters like tunability, visual degradation, compression friendliness, format compliance, encryption ratio, speed, and cryptographic security.

  1. Cryptanalysis of an ergodic chaotic encryption algorithm

    In this paper, we present the results for the security and the possible attacks on a new symmetric key encryption algorithm based on the ergodicity property of a logistic map. After analysis, we use mathematical induction to prove that the algorithm can be attacked by a chosen plaintext attack successfully and give an example to show how to attack it. According to the cryptanalysis of the original algorithm, we improve the original algorithm, and make a brief cryptanalysis. Compared with the original algorithm, the improved algorithm is able to resist a chosen plaintext attack and retain a considerable number of advantages of the original algorithm such as encryption speed, sensitive dependence on the key, strong anti-attack capability, and so on. (general)

  2. Digital image encryption with chaotic map lattices

    Sun Fu-Yan; Lü Zong-Wang

    2011-01-01

    This paper proposes a secure approach for encryption and decryption of digital images with chaotic map lattices.In the proposed encryption process, eight different types of operations are used to encrypt the pixels of an image and one of them will be used for particular pixels decided by the outcome of the chaotic map lattices. To make the cipher more robust against any attacks, the secret key is modified after encrypting each block of sixteen pixels of the image.The experimental results and security analysis show that the proposed image encryption scheme achieves high security and efficiency.

  3. A novel image encryption scheme based on spatial chaos map

    Sun Fuyan [College of Control Science and Engineering, Shandong University, Jinan 250061 (China)], E-mail: fuyan.sun@gmail.com; Liu Shutang [College of Control Science and Engineering, Shandong University, Jinan 250061 (China); Li Zhongqin [HeiLongJiang Institute of Science and Technology, Harbin 150027 (China); Lue Zongwang [Information and Communication College, Guilin University of Electronic and Technology, Guilin 541004 (China); Corporate Engineering Department, Johnson Electric Co. Ltd., Shenzhen 518125 (China)

    2008-11-15

    In recent years, the chaos-based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques, but the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. In this paper, spatial chaos system are used for high degree security image encryption while its speed is acceptable. The proposed algorithm is described in detail. The basic idea is to encrypt the image in space with spatial chaos map pixel by pixel, and then the pixels are confused in multiple directions of space. Using this method one cycle, the image becomes indistinguishable in space due to inherent properties of spatial chaotic systems. Several experimental results, key sensitivity tests, key space analysis, and statistical analysis show that the approach for image cryptosystems provides an efficient and secure way for real time image encryption and transmission from the cryptographic viewpoint.

  4. A novel image encryption scheme based on spatial chaos map

    In recent years, the chaos-based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques, but the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. In this paper, spatial chaos system are used for high degree security image encryption while its speed is acceptable. The proposed algorithm is described in detail. The basic idea is to encrypt the image in space with spatial chaos map pixel by pixel, and then the pixels are confused in multiple directions of space. Using this method one cycle, the image becomes indistinguishable in space due to inherent properties of spatial chaotic systems. Several experimental results, key sensitivity tests, key space analysis, and statistical analysis show that the approach for image cryptosystems provides an efficient and secure way for real time image encryption and transmission from the cryptographic viewpoint

  5. X-ray Digital Image Encryption Algorithm Based on Chaos Theory and Arnold Transformation%基于混沌理论和Arnold变换的X射线数字图像加密算法

    陶亮; 张运楚; 同玉洁

    2015-01-01

    After a single chaotic algorithm encryption, the image also left the outline of the original image, but there is a problem of insufficient strength of the encryption. This paper presents the algorithm of combining two-dimensional Arnold matrix transformation and Chaos Theory for the encryption of X-ray image, uses the features of Arnold disturbing the image position, combines with the theory of chaos encryption to effectively solve the problem of insufficient strength of the single chaotic image encryption algorithm, and finally shows the effectiveness of the algorithm through experiment. Experimental results show that the encryption of this algorithm is very safe.%图像经单一的混沌算法加密后,还留有原图像轮廓,存在加密强度不足的问题。文章提出应用二维Arnold矩阵变换和混沌理论混合加密X射线图像的算法,利用Arnold扰乱图像位置的特点,结合混沌加密理论,有效地解决了单一混沌加密算法对图像加密强度不够的问题。最后,通过实验验证了该算法的有效性。实验结果表明,该算法的加密安全性很高。

  6. Self Contained Encrypted Image Folding

    Rebollo-Neira, Laura; Constantinides, Anthony; Plastino, Angel

    2012-01-01

    The recently introduced approach for Encrypted Image Folding is generalized to make it Self Contained. The goal is achieved by enlarging the folded image so as to embed all the necessary information for the image recovery. The need for extra size is somewhat compensated by considering a transformation with higher folding capacity. Numerical examples show that the size of the resulting cipher image may be significantly smaller than the plain text one. The implementation of the approach is further extended to deal also with color images.

  7. Chaotic trigonometric Haar wavelet with focus on image encryption

    Ahadpour, Sodeif; Sadra, Yaser

    2014-01-01

    In this paper, after reviewing the main points of Haar wavelet transform and chaotic trigonometric maps, we introduce a new perspective of Haar wavelet transform. The essential idea of the paper is given linearity properties of the scaling function of the Haar wavelet. With regard to applications of Haar wavelet transform in image processing, we introduce chaotic trigonometric Haar wavelet transform to encrypt the plain images. In addition, the encrypted images based on a proposed algorithm w...

  8. Color image encryption by using Yang-Gu mixture amplitude-phase retrieval algorithm in gyrator transform domain and two-dimensional Sine logistic modulation map

    Sui, Liansheng; Liu, Benqing; Wang, Qiang; Li, Ye; Liang, Junli

    2015-12-01

    A color image encryption scheme is proposed based on Yang-Gu mixture amplitude-phase retrieval algorithm and two-coupled logistic map in gyrator transform domain. First, the color plaintext image is decomposed into red, green and blue components, which are scrambled individually by three random sequences generated by using the two-dimensional Sine logistic modulation map. Second, each scrambled component is encrypted into a real-valued function with stationary white noise distribution in the iterative amplitude-phase retrieval process in the gyrator transform domain, and then three obtained functions are considered as red, green and blue channels to form the color ciphertext image. Obviously, the ciphertext image is real-valued function and more convenient for storing and transmitting. In the encryption and decryption processes, the chaotic random phase mask generated based on logistic map is employed as the phase key, which means that only the initial values are used as private key and the cryptosystem has high convenience on key management. Meanwhile, the security of the cryptosystem is enhanced greatly because of high sensitivity of the private keys. Simulation results are presented to prove the security and robustness of the proposed scheme.

  9. Research on medical image encryption in telemedicine systems.

    Dai, Yin; Wang, Huanzhen; Zhou, Zixia; Jin, Ziyi

    2016-04-29

    Recently, advances in computers and high-speed communication tools have led to enhancements in remote medical consultation research. Laws in some localities require hospitals to encrypt patient information (including images of the patient) before transferring the data over a network. Therefore, developing suitable encryption algorithms is quite important for modern medicine. This paper demonstrates a digital image encryption algorithm based on chaotic mapping, which uses the no-period and no-convergence properties of a chaotic sequence to create image chaos and pixel averaging. Then, the chaotic sequence is used to encrypt the image, thereby improving data security. With this method, the security of data and images can be improved. PMID:27163302

  10. Study on Digital Image Scrambling Algorithm

    Wu Xue

    2013-01-01

    Encryption algorithm of traditional cryptology has strong safety, but the effect of encrypting images is not good. Digital image scrambling means that a digital image is transformed into a chaotic image which has no evident significance, but the operator can reconstruct the chaotic image into the original image by using the specific algorithm. Image scrambling encryption technology based on chaos theory makes use of chaotic signal to encrypt image data flow, which has the advantages of high s...

  11. Color image encryption based on Coupled Nonlinear Chaotic Map

    Mazloom, Sahar [Faculty of Electrical, Computer and IT Engineering, Qazvin Islamic Azad University, Qazvin (Iran, Islamic Republic of)], E-mail: sahar.mazloom@gmail.com; Eftekhari-Moghadam, Amir Masud [Faculty of Electrical, Computer and IT Engineering, Qazvin Islamic Azad University, Qazvin (Iran, Islamic Republic of)], E-mail: eftekhari@qazviniau.ac.ir

    2009-11-15

    Image encryption is somehow different from text encryption due to some inherent features of image such as bulk data capacity and high correlation among pixels, which are generally difficult to handle by conventional methods. The desirable cryptographic properties of the chaotic maps such as sensitivity to initial conditions and random-like behavior have attracted the attention of cryptographers to develop new encryption algorithms. Therefore, recent researches of image encryption algorithms have been increasingly based on chaotic systems, though the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. This paper proposes a Coupled Nonlinear Chaotic Map, called CNCM, and a novel chaos-based image encryption algorithm to encrypt color images by using CNCM. The chaotic cryptography technique which used in this paper is a symmetric key cryptography with a stream cipher structure. In order to increase the security of the proposed algorithm, 240 bit-long secret key is used to generate the initial conditions and parameters of the chaotic map by making some algebraic transformations to the key. These transformations as well as the nonlinearity and coupling structure of the CNCM have enhanced the cryptosystem security. For getting higher security and higher complexity, the current paper employs the image size and color components to cryptosystem, thereby significantly increasing the resistance to known/chosen-plaintext attacks. The results of several experimental, statistical analysis and key sensitivity tests show that the proposed image encryption scheme provides an efficient and secure way for real-time image encryption and transmission.

  12. A fractal-based image encryption system

    Abd-El-Hafiz, S. K.

    2014-12-01

    This study introduces a novel image encryption system based on diffusion and confusion processes in which the image information is hidden inside the complex details of fractal images. A simplified encryption technique is, first, presented using a single-fractal image and statistical analysis is performed. A general encryption system utilising multiple fractal images is, then, introduced to improve the performance and increase the encryption key up to hundreds of bits. This improvement is achieved through several parameters: feedback delay, multiplexing and independent horizontal or vertical shifts. The effect of each parameter is studied separately and, then, they are combined to illustrate their influence on the encryption quality. The encryption quality is evaluated using different analysis techniques such as correlation coefficients, differential attack measures, histogram distributions, key sensitivity analysis and the National Institute of Standards and Technology (NIST) statistical test suite. The obtained results show great potential compared to other techniques.

  13. 基于遗传算法的图像加密技术及实现%Image encryption technology based on genetic algorithm and its implementation

    周华; 黄廷磊

    2015-01-01

    为实现数字图像的安全存储和传输,提出一种基于遗传算法的图像加密技术。由该技术生成的密钥序列更具随机性和复杂性,可将一幅图像转化为另一幅图像,从而实现对原图像的加密。Matlab实验结果表明,该算法有效、可行。%In order to achieve secure storage and transmission of digital images,an image encryption technology based on the genetic algorithm is proposed.Secret key sequence generated is more random and complex by this technique.An image can be transformed into another image,so as to achieve the original image encryption.The Matlab experimental results show that the algorithm is effective and feasible.

  14. Image Encryption Based on Diffusion and Multiple Chaotic Maps

    Sathishkumar, G A; Sriraam, Dr N; 10.5121/ijnsa.2011.3214

    2011-01-01

    In the recent world, security is a prime important issue, and encryption is one of the best alternative way to ensure security. More over, there are many image encryption schemes have been proposed, each one of them has its own strength and weakness. This paper presents a new algorithm for the image encryption/decryption scheme. This paper is devoted to provide a secured image encryption technique using multiple chaotic based circular mapping. In this paper, first, a pair of sub keys is given by using chaotic logistic maps. Second, the image is encrypted using logistic map sub key and in its transformation leads to diffusion process. Third, sub keys are generated by four different chaotic maps. Based on the initial conditions, each map may produce various random numbers from various orbits of the maps. Among those random numbers, a particular number and from a particular orbit are selected as a key for the encryption algorithm. Based on the key, a binary sequence is generated to control the encryption algorit...

  15. PERFORMANCE ANALYSIS OF IMAGE SECURITY BASED ON ENCRYPTED HYBRID COMPRESSION

    D. Ramkumar

    2014-01-01

    Full Text Available In this research, we propose an image security scheme using hybrid compression techniques. In this scheme, the data is being provided two-fold security by both encryption stage and hiding stage. The data/message which has to be secured undergoes encryption technique at the initial stage. In this stage, the permutation algorithm is employed which requires a pair of numbers as a key to permute the original message. Following the encryption stage, the deformed message is then embedded onto a JPEG image by considering the low and high quantization tables. The main motivation behind this research work is to provide image security through compression. The final result is an encrypted and compressed JPEG image with a different image quality. The receiver has to perform the reverse process to extract the original data/information. The performance analysis is performed in terms of PSNR for different quantization tables.

  16. Optical encryption for large-sized images

    Sanpei, Takuho; Shimobaba, Tomoyoshi; Kakue, Takashi; Endo, Yutaka; Hirayama, Ryuji; Hiyama, Daisuke; Hasegawa, Satoki; Nagahama, Yuki; Sano, Marie; Oikawa, Minoru; Sugie, Takashige; Ito, Tomoyoshi

    2016-02-01

    We propose an optical encryption framework that can encrypt and decrypt large-sized images beyond the size of the encrypted image using our two methods: random phase-free method and scaled diffraction. In order to record the entire image information on the encrypted image, the large-sized images require the random phase to widely diffuse the object light over the encrypted image; however, the random phase gives rise to the speckle noise on the decrypted images, and it may be difficult to recognize the decrypted images. In order to reduce the speckle noise, we apply our random phase-free method to the framework. In addition, we employ scaled diffraction that calculates light propagation between planes with different sizes by changing the sampling rates.

  17. Dual-Layer Video Encryption using RSA Algorithm

    Chadha, Aman; Mallik, Sushmit; Chadha, Ankit; Johar, Ravdeep; Mani Roja, M.

    2015-04-01

    This paper proposes a video encryption algorithm using RSA and Pseudo Noise (PN) sequence, aimed at applications requiring sensitive video information transfers. The system is primarily designed to work with files encoded using the Audio Video Interleaved (AVI) codec, although it can be easily ported for use with Moving Picture Experts Group (MPEG) encoded files. The audio and video components of the source separately undergo two layers of encryption to ensure a reasonable level of security. Encryption of the video component involves applying the RSA algorithm followed by the PN-based encryption. Similarly, the audio component is first encrypted using PN and further subjected to encryption using the Discrete Cosine Transform. Combining these techniques, an efficient system, invulnerable to security breaches and attacks with favorable values of parameters such as encryption/decryption speed, encryption/decryption ratio and visual degradation; has been put forth. For applications requiring encryption of sensitive data wherein stringent security requirements are of prime concern, the system is found to yield negligible similarities in visual perception between the original and the encrypted video sequence. For applications wherein visual similarity is not of major concern, we limit the encryption task to a single level of encryption which is accomplished by using RSA, thereby quickening the encryption process. Although some similarity between the original and encrypted video is observed in this case, it is not enough to comprehend the happenings in the video.

  18. Hardware Realization of Chaos Based Symmetric Image Encryption

    Barakat, Mohamed L.

    2012-06-01

    This thesis presents a novel work on hardware realization of symmetric image encryption utilizing chaos based continuous systems as pseudo random number generators. Digital implementation of chaotic systems results in serious degradations in the dynamics of the system. Such defects are illuminated through a new technique of generalized post proceeding with very low hardware cost. The thesis further discusses two encryption algorithms designed and implemented as a block cipher and a stream cipher. The security of both systems is thoroughly analyzed and the performance is compared with other reported systems showing a superior results. Both systems are realized on Xilinx Vetrix-4 FPGA with a hardware and throughput performance surpassing known encryption systems.

  19. Perceptual security of encrypted images based on wavelet scaling analysis

    Vargas-Olmos, C.; Murguía, J. S.; Ramírez-Torres, M. T.; Mejía Carlos, M.; Rosu, H. C.; González-Aguilar, H.

    2016-08-01

    The scaling behavior of the pixel fluctuations of encrypted images is evaluated by using the detrended fluctuation analysis based on wavelets, a modern technique that has been successfully used recently for a wide range of natural phenomena and technological processes. As encryption algorithms, we use the Advanced Encryption System (AES) in RBT mode and two versions of a cryptosystem based on cellular automata, with the encryption process applied both fully and partially by selecting different bitplanes. In all cases, the results show that the encrypted images in which no understandable information can be visually appreciated and whose pixels look totally random present a persistent scaling behavior with the scaling exponent α close to 0.5, implying no correlation between pixels when the DFA with wavelets is applied. This suggests that the scaling exponents of the encrypted images can be used as a perceptual security criterion in the sense that when their values are close to 0.5 (the white noise value) the encrypted images are more secure also from the perceptual point of view.

  20. Techniques for a selective encryption of uncompressed and compressed images

    Van Droogenbroeck, Marc; Benedett, Raphaël

    2002-01-01

    This paper describes several techniques to encrypt uncompressed and compressed images. We first present the aims of image encryption. In the usual ways to encryption, all the information is encrypted. But this is not mandatory. In this paper we follow the principles of a technique initially proposed by MAPLES et al. [1] and encrypt only a part of the image content in order to be able to visualize the encrypted images, although not with full precision. This concept leads to techniques that can...

  1. How Good Is The DES Algorithm In Image Ciphering?

    Said F. El-Zoghdy

    2011-03-01

    Full Text Available Digital Images and video encryption plays an important role in today’s multimedia world. Many encryption schemes have been proposed to provide security for digital images. Usually the symmetric key ciphering algorithms are used in encrypting digital images because it is fast and use the techniques for block and stream ciphers. Data Encryption Standard is symmetric key encryption algorithm. In spite of the successful cracking of the data encryption standard by massive brute force attacks, data encryption standard algorithm is an entrenched technology and still useful for many purposes. In this paper, we use some of the image quality encryption measuring factors to study the effect of data encryption standard algorithm in image ciphering. The results show that the data encryption standard algorithm is fast and it achieves a good encryption rate for image ciphering using different modes of operation.

  2. A Novel Image Encryption Algorithm Based on the Two-Dimensional Logistic Map and the Latin Square Image Cipher

    Machkour, M.; Saaidi, A.; Benmaati, M. L.

    2015-12-01

    In this paper, we introduce a new hybrid system consisting of a permutation-substitution network based on two different encryption techniques: chaotic systems and the Latin square. This homogeneity between the two systems allows us to provide the good properties of confusion and diffusion, robustness to the integration of noise in decryption. The security analysis shows that the system is secure enough to resist brute-force attack, differential attack, chosen-plaintext attack, known-plaintext attack and statistical attack. Therefore, this robustness is proven and justified.

  3. A Research paper: An ASCII value based data encryption algorithm and its comparison with other symmetric data encryption algorithms

    Akanksha Mathur

    2012-09-01

    Full Text Available Encryption is the process of transforming plaintext into the ciphertext where plaintext is the input to the encryption process and ciphertext is the output of the encryption process. Decryption isthe process of transforming ciphertext into the plaintext where ciphertext is the input to the decryption process and plaintext is the output of the decryption process. There are various encryption algorithms exist classified as symmetric and asymmetric encryption algorithms. Here, I present an algorithm for data encryption and decryption which is based on ASCII values of characters in the plaintext. This algorithm is used to encrypt data by using ASCII values of the data to be encrypted. The secret used will be modifying o another string and that string is used as a key to encrypt or decrypt the data. So, it can be said that it is a kind of symmetric encryption algorithm because it uses same key for encryption anddecryption but by slightly modifying it. This algorithm operates when the length of input and the length of key are same.

  4. The Application Research of MD5 Encryption Algorithm in DCT Digital Watermarking

    Xijin, Wang; Linxiu, Fan

    This article did the preliminary study of the application of algorithm for MD5 in the digital watermark. It proposed that copyright information will be encrypted using an algorithm MD5, and made rules for the second value image watermarks, through DCT algorithm that embeds an image by the carrier. The extraction algorithms can pick up the watermark and restore MD5 code.

  5. A New Color Image Encryption Scheme Using CML and a Fractional-Order Chaotic System

    Wu, Xiangjun; Li, Yang; Kurths, Jürgen

    2015-01-01

    The chaos-based image cryptosystems have been widely investigated in recent years to provide real-time encryption and transmission. In this paper, a novel color image encryption algorithm by using coupled-map lattices (CML) and a fractional-order chaotic system is proposed to enhance the security and robustness of the encryption algorithms with a permutation-diffusion structure. To make the encryption procedure more confusing and complex, an image division-shuffling process is put forward, where the plain-image is first divided into four sub-images, and then the position of the pixels in the whole image is shuffled. In order to generate initial conditions and parameters of two chaotic systems, a 280-bit long external secret key is employed. The key space analysis, various statistical analysis, information entropy analysis, differential analysis and key sensitivity analysis are introduced to test the security of the new image encryption algorithm. The cryptosystem speed is analyzed and tested as well. Experimental results confirm that, in comparison to other image encryption schemes, the new algorithm has higher security and is fast for practical image encryption. Moreover, an extensive tolerance analysis of some common image processing operations such as noise adding, cropping, JPEG compression, rotation, brightening and darkening, has been performed on the proposed image encryption technique. Corresponding results reveal that the proposed image encryption method has good robustness against some image processing operations and geometric attacks. PMID:25826602

  6. ecure Reversible Data Hiding in Encrypted Images by Allocating Memory before Encryption via Security keys

    Priya Jambhulkar

    2014-06-01

    Full Text Available Digital image and information embedding system have number of important multimedia applications. Recently, attention is paid to reversible data hiding (RDH in encrypted images is more, since it maintains the excellent property that the original cover can be lossless recovered after embedded data is extracted while protecting the image content’s confidentiality. RDH is a technique used to hide data inside image for high security in such a way that original data is not visible. All previous methods embed data by reversibly vacating room from the encrypted images, which may be subject to some errors on data extraction and/or image restoration. In this paper, we propose another method in which we simply encrypt an image without its header by using our own algorithm. And thus it is easy for the data hider to reversibly embed data in the encrypted image. The proposed method can achieve real reversibility, that is, data extraction and image recovery are free of any error.

  7. Secure Reversible Data Hiding in Encrypted Images by Allocating Memory before Encryption via Security keys

    Priya Jambhulkar

    2015-11-01

    Full Text Available Digital image and information embedding system have number of important multimedia applications. Recently, attention is paid to reversible data hiding (RDH in encrypted images is more, since it maintains the excellent property that the original cover can be lossless recovered after embedded data is extracted while protecting the image content’s confidentiality. RDH is a technique used to hide data inside image for high security in such a way that original data is not visible. All previous methods embed data by reversibly vacating room from the encrypted images, which may be subject to some errors on data extraction and/or image restoration. In this paper, we propose another method in which we simply encrypt an image without its header by using our own algorithm. And thus it is easy for the data hider to reversibly embed data in the encrypted image. The proposed method can achieve real reversibility, that is, data extraction and image recovery are free of any error.

  8. Multiple-image encryption with bit-plane decomposition and chaotic maps

    Tang, Zhenjun; Song, Juan; Zhang, Xianquan; Sun, Ronghai

    2016-05-01

    Image encryption is an efficient technique of image content protection. In this work, we propose a useful image encryption algorithm for multiple grayscale images. The proposed algorithm decomposes input images into bit-planes, randomly swaps bit-blocks among different bit-planes, and conducts XOR operation between the scrambled images and secret matrix controlled by chaotic map. Finally, an encrypted PNG image is obtained by viewing four scrambled grayscale images as its red, green, blue and alpha components. Many simulations are done to illustrate efficiency of our algorithm.

  9. OCML-based colour image encryption

    The chaos-based cryptographic algorithms have suggested some new ways to develop efficient image-encryption schemes. While most of these schemes are based on low-dimensional chaotic maps, it has been proposed recently to use high-dimensional chaos namely spatiotemporal chaos, which is modelled by one-way coupled-map lattices (OCML). Owing to their hyperchaotic behaviour, such systems are assumed to enhance the cryptosystem security. In this paper, we propose an OCML-based colour image encryption scheme with a stream cipher structure. We use a 192-bit-long external key to generate the initial conditions and the parameters of the OCML. We have made several tests to check the security of the proposed cryptosystem namely, statistical tests including histogram analysis, calculus of the correlation coefficients of adjacent pixels, security test against differential attack including calculus of the number of pixel change rate (NPCR) and unified average changing intensity (UACI), and entropy calculus. The cryptosystem speed is analyzed and tested as well.

  10. OCML-based colour image encryption

    Rhouma, Rhouma [6' tel, Ecole Superieure de Telecommunications (Sup' com), BP Numero 50, 6014 Mtorech, Gabes (Tunisia)], E-mail: rhoouma@yahoo.fr; Meherzi, Soumaya [6' tel, Ecole Superieure de Telecommunications (Sup' com), BP Numero 50, 6014 Mtorech, Gabes (Tunisia); LSS/SUPELEC/CNRS, Plateau de Moulon, 91192 Gif-sur-Yvette, Cedex (France)], E-mail: mehrzi@lss.supelec.fr; Belghith, Safya [6' tel, Ecole Superieure de Telecommunications (Sup' com), BP Numero 50, 6014 Mtorech, Gabes (Tunisia)], E-mail: safya.belghith@enit.rnu.tn

    2009-04-15

    The chaos-based cryptographic algorithms have suggested some new ways to develop efficient image-encryption schemes. While most of these schemes are based on low-dimensional chaotic maps, it has been proposed recently to use high-dimensional chaos namely spatiotemporal chaos, which is modelled by one-way coupled-map lattices (OCML). Owing to their hyperchaotic behaviour, such systems are assumed to enhance the cryptosystem security. In this paper, we propose an OCML-based colour image encryption scheme with a stream cipher structure. We use a 192-bit-long external key to generate the initial conditions and the parameters of the OCML. We have made several tests to check the security of the proposed cryptosystem namely, statistical tests including histogram analysis, calculus of the correlation coefficients of adjacent pixels, security test against differential attack including calculus of the number of pixel change rate (NPCR) and unified average changing intensity (UACI), and entropy calculus. The cryptosystem speed is analyzed and tested as well.

  11. Single Core Hardware Module to Implement Partial Encryption of Compressed Image

    Mamun B.I. Reaz; M. S. Amin; Fazida H. Hashim; K Asaduzzaman

    2011-01-01

    Problem statement: Real-time secure image and video communication is challenging due to the processing time and computational requirement for encryption and decryption. In order to cope with these concerns, innovative image compression and encryption techniques are required. Approach: In this research, we have introduced partial encryption technique on compressed images and implemented the algorithm on Altera FLEX10K FPGA device that allows for efficient hardware implementation. The compressi...

  12. Image Encryption Based On Diffusion And Multiple Chaotic Maps

    G.A.Sathishkumar

    2011-03-01

    Full Text Available In the recent world, security is a prime important issue, and encryption is one of the best alternative wayto ensure security. More over, there are many image encryption schemes have been proposed, each one ofthem has its own strength and weakness. This paper presents a new algorithm for the imageencryption/decryption scheme. This paper is devoted to provide a secured image encryption techniqueusing multiple chaotic based circular mapping. In this paper, first, a pair of sub keys is given by usingchaotic logistic maps. Second, the image is encrypted using logistic map sub key and in its transformationleads to diffusion process. Third, sub keys are generated by four different chaotic maps. Based on theinitial conditions, each map may produce various random numbers from various orbits of the maps.Among those random numbers, a particular number and from a particular orbit are selected as a key forthe encryption algorithm. Based on the key, a binary sequence is generated to control the encryptionalgorithm. The input image of 2-D is transformed into a 1- D array by using two different scanningpattern (raster and Zigzag and then divided into various sub blocks. Then the position permutation andvalue permutation is applied to each binary matrix based on multiple chaos maps. Finally the receiveruses the same sub keys to decrypt the encrypted images. The salient features of the proposed imageencryption method are loss-less, good peak signal –to noise ratio (PSNR, Symmetric key encryption, lesscross correlation, very large number of secret keys, and key-dependent pixel value replacement.

  13. Watermarking patient data in encrypted medical images

    A Lavanya; V Natarajan

    2012-12-01

    In this paper, we propose a method for watermarking medical images for data integrity which consists of image encryption, data embedding and image-recovery phases. Data embedding can be completely recovered from the watermarked image after the watermark has been extracted. In the proposed method, we utilize standard stream cipher for image encryption and selecting non-region of interest tile to embed patient data. We show that the lower bound of the PSNR (peak-signal-to-noise-ratio) values for medical images is about 48 dB. Experimental results demonstrate that the proposed scheme can embed a large amount of data while keeping high visual quality of test images.

  14. Image compression-encryption scheme based on hyper-chaotic system and 2D compressive sensing

    Zhou, Nanrun; Pan, Shumin; Cheng, Shan; Zhou, Zhihong

    2016-08-01

    Most image encryption algorithms based on low-dimensional chaos systems bear security risks and suffer encryption data expansion when adopting nonlinear transformation directly. To overcome these weaknesses and reduce the possible transmission burden, an efficient image compression-encryption scheme based on hyper-chaotic system and 2D compressive sensing is proposed. The original image is measured by the measurement matrices in two directions to achieve compression and encryption simultaneously, and then the resulting image is re-encrypted by the cycle shift operation controlled by a hyper-chaotic system. Cycle shift operation can change the values of the pixels efficiently. The proposed cryptosystem decreases the volume of data to be transmitted and simplifies the keys distribution simultaneously as a nonlinear encryption system. Simulation results verify the validity and the reliability of the proposed algorithm with acceptable compression and security performance.

  15. A novel color image encryption scheme using alternate chaotic mapping structure

    Wang, Xingyuan; Zhao, Yuanyuan; Zhang, Huili; Guo, Kang

    2016-07-01

    This paper proposes an color image encryption algorithm using alternate chaotic mapping structure. Initially, we use the R, G and B components to form a matrix. Then one-dimension logistic and two-dimension logistic mapping is used to generate a chaotic matrix, then iterate two chaotic mappings alternately to permute the matrix. For every iteration, XOR operation is adopted to encrypt plain-image matrix, then make further transformation to diffuse the matrix. At last, the encrypted color image is obtained from the confused matrix. Theoretical analysis and experimental results has proved the cryptosystem is secure and practical, and it is suitable for encrypting color images.

  16. Multiple Encryption-based Algorithm of Agricultural Product Trace Code

    2012-01-01

    To establish a sound traceability system of agricultural products and guarantee security of agricultural products,an algorithm is proposed to encrypt trace code of agricultural products.Original trace code consists of 34 digits indicating such information as place of origin,name of product,date of production and authentication.Area code is used to indicate enterprise information,the encrypted algorithm is designed because of the increasing code length,such coding algorithms as system conversion and section division are applied for the encrypted conversion of code of origin place and production date code,moreover,section identification code and authentication code are permutated and combined to produce check code.Through the multiple encryption and code length compression,34 digits are compressed to 20 on the basis of ensuring complete coding information,shorter code length and better encryption enable the public to know information about agricultural products without consulting professional database.

  17. A NUMERICAL METHOD BASED ENCRYPTION ALGORITHM WITH STEGANOGRAPHY

    Amartya Ghosh

    2013-02-01

    Full Text Available Now-a-days many encryption algorithms have been proposed for network security. In this paper, a new cryptographic algorithm for network security is proposed to assist the effectiveness of network security. Here symmetric key concept instead of public key is considered to develop the encryption – decryption algorithm. Also, to give more security in the algorithm, the idea of one way function alongwith Newton’s method is applied as a secret key to the proposed work as well as Digital Signature Standard (DSS technology is used to send the key. Moreover, steganography is used to hide the cipher within a picture in encryption algorithm. In brief, a numerical method based secret key encryption – decryption algorithm is developed using steganography to enhance the network security.

  18. Developing and Evaluation of New Hybrid Encryption Algorithms

    DiaaSalama AbdElminaam

    2014-03-01

    Full Text Available Wireless Sensor networks consist of hundreds or thousands of low cost, low power and self-organizing nodes which are highly distributed. As wireless sensor networks continue to grow, so does the need for effective security mechanisms because sensor networks may interact with sensitive data. Encryption algorithms play good roles in information security systems (ISS. Those algorithms consume a significant amount of computing resources such as battery power. Wireless Sensor networks are powered by a battery which is a very limited resource. At present, various types of cryptographic algorithms provide high security to information on networks, but there are also has some drawbacks.  The present asymmetric encryption methods and symmetric encryption methods can offer the security levels but with many limitations. For instance key maintenance is a great problem faced in symmetric encryption methods and less security level is the problem of asymmetric encryption methods even though key maintenance is easy. To improve the strength of these algorithms, we propose a new hybrid cryptographic algorithm in this paper. The algorithm is designed using combination of two symmetric cryptographic techniques and two Asymmetric cryptographic techniques. This protocol provides three cryptographic primitives, integrity, confidentiality and authentication. It is a hybrid encryption method where elliptical curve cryptography (ECC and advanced encryption (AES are combined to provide node encryption. RSA algorithm and Blowfish are combined to provide authentication and (MD5 for integrity. The results show that the proposed hybrid cryptographic algorithm gives better performance in terms of computation time and the size of cipher text.This paper tries to present a fair comparison between the new protocols with four existing different hybrid protocols according to power consumption. A comparison has been conducted for those protocols at different settings for each

  19. Study on Digital Image Scrambling Algorithm

    Wu Xue

    2013-07-01

    Full Text Available Encryption algorithm of traditional cryptology has strong safety, but the effect of encrypting images is not good. Digital image scrambling means that a digital image is transformed into a chaotic image which has no evident significance, but the operator can reconstruct the chaotic image into the original image by using the specific algorithm. Image scrambling encryption technology based on chaos theory makes use of chaotic signal to encrypt image data flow, which has the advantages of high safety, rapid encryption speed, large key space and good scrambling effect. The paper studies invalid-key and quasi invalid-key existed in chaotic sequence which is generated by Logistic map, and proposes image scrambling encryption algorithm based on mixed and chaotic sequence. The algorithm has a good robustness for the JPEG compression with the fixed coefficient, and a good fragileness for the illegal manipulation.

  20. IMAGE ENCRYPTION USING PERMUTATION AND ROTATIONAL XOR TECHNIQUE

    Avi Dixit

    2012-07-01

    Full Text Available Encryption is used to securely transmit data in open networks. Each type of data has its own features, therefore different techniques should be used to protect confidential image data from unauthorized access. Most of the available encryption algorithms are mainly used for textual data and may not be suitable for multimedia data such as images. In this paper, we introduce an algorithm. The binary code of the pixel values of a colour image is extracted and permuted according to the entered 8 bit key which is followed by the permutation of every 8 consecutive pixels [4]. The image is further divided into blocks which are shifted accordingly. The above mentioned technique has a few drawbacks, like the small key size. To further enforce the encryption another method is appended to it which requires a 43 digit key. The encryption takes a total of 10 rounds in which two keys are use, both of which are derived from the 43 digit entered key. The results showed that the correlation between image elements was significantly decreased by using the proposed technique.

  1. Secured Reversible Data Hiding In Encrypted Images Using Hyper Chaos

    T.M. Amarunnishad

    2014-11-01

    Full Text Available Recently, more and more attention is paid to reversible data hiding (RDH in encrypted images, since it maintains the excellent property that the original cover can be losslessly recovered after embedded data is extracted while protecting the image content’s confidentiality. All previous methods embed data by reversibly vacating room from the encrypted images, which may be subject to some errors on data extraction and/or image restoration. Here a novel method is proposed by reserving room before encryption with a traditional RDH algorithm, and thus it is easy for the data hider to reversibly embed data in the encrypted image. Moreover data to be embedded is shuffled using a hyper chaotic function which is difficult to be extracted from the stego image without original key. A digital water mark is also embedded which ensures integrity of the data. The proposed method has been validated against three other available RDH schemes and it is observed that the proposed scheme outperforms these RDH schemes both in visual quality and payload. The proposed method can achieve real reversibility, that is, data extraction and image recovery are free of any error.

  2. Fresnel domain double-phase encoding encryption of color image via ptychography

    Qiao, Liang; Wang, Yali; Li, Tuo; Shi, Yishi

    2015-10-01

    In this paper, color image encryption combined with ptychography has been investigated. Ptychographic imaging possesses a remarkable advantage of simple optics architecture and complex amplitude of object can be reconstructed just by a series of diffraction intensity patterns via aperture movement. Traditional technique of three primary color synthesis is applied for encrypting color image. In order to reduce physical limitations, the encryption's algorithm is based on Fresnel transformation domain. It is illustrated that the proposed optical encryption scheme has well ability to recover the encrypted color plaintext and advances in security enhancement thanks to introducing ptychography, since light probe as key factor enlarges the key space. Finally, the encryption's immunity to noise and reconstruction impact from lateral offset of probe has been investigated.

  3. Several types of the chaotic mapping image encryption algorithm%几类混沌映射图像加密算法的比较

    薛香莲

    2015-01-01

    对图像信息安全技术进行了研究,报告了现阶段图像加密的相关现状,分析了基于混沌理论的图像加密的主要方法,提出分别用一维混沌映射Logistic、二维混沌映射2DLogistic以及Chen超混沌映射对图像进行位置和值置乱来实现图像加密,并从实验仿真结果、密钥空间、密钥灵敏性、灰度直方图、置乱程度以及加密时间等方面来比较以上三种混沌理论作用于图像加密中的各自优缺点。%Studied the image information security technology,the report related to the status quo of the current image encryption,analyzed the main method of image encryption based on chaos theory,put forward respectively in one-dimensional chaotic map Logistic,2 dlogistic two-dimensional chaos mapping and hyperchaos mapping for the position and value of Chen to behave in such a way to realize image encryption, and from the experimental simulation results,the key space,key sensitivity,gray histogram,scrambling degree and the encryption time and so on to compare the above three kinds of chaos theory applied to image encryption in the respective advantages and disadvantages.

  4. Selective image encryption for Medical and Satellite Images

    NaveenKumar S K; Panduranga H T

    2013-01-01

    Information security plays a very important role in fast growing information and communication technology. Few applications like medical image security and satellite image security needs to secure only selected portion of the image. This paper describes a concept of selective image encryption in two ways. First method divides the image in to sub blocks, then selected blocks are applied to encryption process. Second method automatically detects the positions of objects, and then selected objec...

  5. Selective image encryption for Medical and Satellite Images

    NaveenKumar S K

    2013-02-01

    Full Text Available Information security plays a very important role in fast growing information and communication technology. Few applications like medical image security and satellite image security needs to secure only selected portion of the image. This paper describes a concept of selective image encryption in two ways. First method divides the image in to sub blocks, then selected blocks are applied to encryption process. Second method automatically detects the positions of objects, and then selected objects are applied to encryption process. Morphological techniques are used to detect the positions of the objects in given images. These two approaches are specifically developed to encrypt the portion of an image in medical images and satellite image.

  6. 基于五维混沌系统的图像加密研究%Five-dimensional chaotic system based image encryption algorithm

    高亮; 朱博; 孙鸣; 朱建良

    2011-01-01

    随着计算机技术、信息技术和通讯技术等高科技技术在近年来的迅猛发展,信息加密越来越受到人们的重视,提出了基于五维混沌系统用来实现图像加密的方法,并利用迭代次数和方式作为密码,实现了图像加密和解密,为信息加密提供了一种新方法.%With computer technology, information technology and communications technology, high technology, rapid development in recent years, more and more people pay close attention to information encryption. This paper, based on five-dimensional chaotic system realizes image encryption method, and means of using the number of iterations as the password, to realize the image encryption and decryption,the information provides a new method of encryption.

  7. Classification of Novel Selected Region of Interest for Color Image Encryption

    Lahieb Mohammed Jawad

    2015-04-01

    Full Text Available Securing digital image in exchanging huge multimedia data over internet with limited bandwidth is a significant and sensitive issue. Selective image encryption being an effective method for reducing the amount of encrypted data can achieve adequate security enhancement. Determining and selecting the region of interest in digital color images is challenging for selective image encryption due to their complex structure and distinct regions of varying importance. We propose a new feature in acquiring and selecting Region of Interest (ROI for the color images to develop a selective encryption scheme. The hybrid domain is used to encrypt regions based on chaotic map approach which automatically generates secret key. This new attribute is a vitality facet representing the noteworthy part of the color image. The security performance of selective image encryption is found to enhance considerably based on the rates of encrypted area selection. Computation is performed using MATLAB R2008a codes on eight images (Lena, Pepper, Splash, Airplane, House, Tiffany, Baboon and Sailboat each of size 512*512 pixels obtained from standard USC-SIPI Image Database. A block size of 128*128 pixels with threshold levels 0.0017 and 0.48 are employed. Results are analyzed and compared with edge detection method using the same algorithm. Encrypted area, entropy and correlation coefficients performances reveal that the proposed scheme achieves good alternative in the confined region of interest, fulfills the desired confidentiality and protects image privacy.

  8. A Parallel Encryption Algorithm Based on Piecewise Linear Chaotic Map

    Xizhong Wang

    2013-01-01

    Full Text Available We introduce a parallel chaos-based encryption algorithm for taking advantage of multicore processors. The chaotic cryptosystem is generated by the piecewise linear chaotic map (PWLCM. The parallel algorithm is designed with a master/slave communication model with the Message Passing Interface (MPI. The algorithm is suitable not only for multicore processors but also for the single-processor architecture. The experimental results show that the chaos-based cryptosystem possesses good statistical properties. The parallel algorithm provides much better performance than the serial ones and would be useful to apply in encryption/decryption file with large size or multimedia.

  9. Encryption of Messages and Images Using Compressed Sensing

    Daňková, M.

    2015-01-01

    The article deals with compressed sensing used to encrypt data. It allows performing signal capturing, its compression and encryption at the same time. The measurement matrix is generated using a secret key and is exploited for encryption. The article shows an example of its utilization at text and image message, moreover the Arnold transform is used in colour images for increasing security.

  10. Single Core Hardware Module to Implement Partial Encryption of Compressed Image

    Mamun B.I. Reaz

    2011-01-01

    Full Text Available Problem statement: Real-time secure image and video communication is challenging due to the processing time and computational requirement for encryption and decryption. In order to cope with these concerns, innovative image compression and encryption techniques are required. Approach: In this research, we have introduced partial encryption technique on compressed images and implemented the algorithm on Altera FLEX10K FPGA device that allows for efficient hardware implementation. The compression algorithm decomposes images into several different parts. We have used a secured encryption algorithm to encrypt only the crucial parts, which are considerably smaller than the original image, which result in significant reduction in processing time and computational requirement for encryption and decryption. The breadth-first traversal linear lossless quadtree decomposition method is used for the partial compression and RSA is used for the encryption. Results: Functional simulations were commenced to verify the functionality of the individual modules and the system on four different images. We have validated the advantage of the proposed approach through comparison, verification and analysis. The design has utilized 2928 units of LC with a system frequency of 13.42MHz. Conclusion: In this research, the FPGA prototyping of a partial encryption of compressed images using lossless quadtree compression and RSA encryption has been successfully implemented with minimum logic cells. It is found that the compression process is faster than the decompression process in linear quadtree approach. Moreover, the RSA simulations show that the encryption process is faster than the decryption process for all four images tested.

  11. The research on image encryption method based on parasitic audio watermark

    Gao, Pei-pei; Zhu, Yao-ting; Zhang, Shi-tao

    2010-11-01

    In order to improve image encryption strength, an image encryption method based on parasitic audio watermark was proposed in this paper, which relies on double messages such as image domain and speech domain to do image encryption protection. The method utilizes unique Chinese phonetics synthesis algorithm to complete audio synthesis with embedded text, then separate this sentence information into prosodic phrase, obtains complete element set of initial consonant and compound vowel that reflects audio feature of statement. By sampling and scrambling the initial consonant and compound vowel element, synthesizing them with image watermark, and embedding the compound into the image to be encrypted in frequency domain, the processed image contains image watermark information and parasitizes audio feature information. After watermark extraction, using the same phonetics synthesis algorithm the audio information is synthesized and compared with the original. Experiments show that any decryption method in image domain or speech domain could not break encryption protection and image gains higher encryption strength and security level by double encryption.

  12. Overview on Selective Encryption of Image and Video: Challenges and Perspectives

    2009-03-01

    Full Text Available In traditional image and video content protection schemes, called fully layered, the whole content is first compressed. Then, the compressed bitstream is entirely encrypted using a standard cipher (DES, AES, IDEA, etc.. The specific characteristics of this kind of data (high-transmission rate with limited bandwidth make standard encryption algorithms inadequate. Another limitation of fully layered systems consists of altering the whole bitstream syntax which may disable some codec functionalities. Selective encryption is a new trend in image and video content protection. It consists of encrypting only a subset of the data. The aim of selective encryption is to reduce the amount of data to encrypt while preserving a sufficient level of security. This computation saving is very desirable especially in constrained communications (real-time networking, high-definition delivery, and mobile communications with limited computational power devices. In addition, selective encryption allows preserving some codec functionalities such as scalability. This tutorial is intended to give an overview on selective encryption algorithms. The theoretical background of selective encryption, potential applications, challenges, and perspectives is presented.

  13. Overview on Selective Encryption of Image and Video: Challenges and Perspectives

    Massoudi A

    2008-01-01

    Full Text Available In traditional image and video content protection schemes, called fully layered, the whole content is first compressed. Then, the compressed bitstream is entirely encrypted using a standard cipher (DES, AES, IDEA, etc.. The specific characteristics of this kind of data (high-transmission rate with limited bandwidth make standard encryption algorithms inadequate. Another limitation of fully layered systems consists of altering the whole bitstream syntax which may disable some codec functionalities. Selective encryption is a new trend in image and video content protection. It consists of encrypting only a subset of the data. The aim of selective encryption is to reduce the amount of data to encrypt while preserving a sufficient level of security. This computation saving is very desirable especially in constrained communications (real-time networking, high-definition delivery, and mobile communications with limited computational power devices. In addition, selective encryption allows preserving some codec functionalities such as scalability. This tutorial is intended to give an overview on selective encryption algorithms. The theoretical background of selective encryption, potential applications, challenges, and perspectives is presented.

  14. Multiple-image encryption based on computational ghost imaging

    Wu, Jingjing; Xie, Zhenwei; Liu, Zhengjun; Liu, Wei; Zhang, Yan; Liu, Shutian

    2016-01-01

    We propose an optical multiple-image encryption scheme based on computational ghost imaging with the position multiplexing. In the encryption process, each plain image is encrypted into an intensity vector by using the computational ghost imaging with a different diffraction distance. The final ciphertext is generated by superposing all the intensity vectors together. Different from common multiple-image cryptosystems, the ciphertext in the proposed scheme is simply an intensity vector instead of a complex amplitude. Simulation results are presented to demonstrate the validity and security of the proposed multiple-image encryption method. The multiplexing capacity of the proposed method is also investigated. Optical experiment is presented to verify the validity of the proposed scheme in practical application.

  15. Image Encryption Using Fibonacci-Lucas Transformation

    Mishra, Minati; Mishra, Priyadarsini; Adhikary, M. C.; Kumar, Sunit

    2012-01-01

    Secret communication techniques are of great demand since last 3000 years due to the need of information security and confidentiality at various levels of communication such as while communicating confidential personal data, medical data of patients, defence and intelligence information of countries, data related to examinations etc. With advancements in image processing research, Image encryption and Steganographic techniques have gained popularity over other forms of hidden communication te...

  16. ON IMAGE ENCRYPTION ALGORITHM BASED ON DISCRETE FOURIER TRANSFORMATION INTEGRATING WITH DOUBLING CHAOTIC MAP%基于离散傅里叶变换融合双混沌映射的图像加密算法研究

    芮坤坤

    2014-01-01

    频域加密非常适用于大多数数字和光学图像处理体系,而空间域加密则适用于图像通信。为了充分利用在图像频率域和空间域加密的优势,进一步提高图像加密系统的安全性,提出基于离散的傅里叶变换和双混沌映射的图像加密算法,同时对图像的频率域和空间域进行加密。首先,利用二维离散的傅里叶变换将图像从空间域转换成频率域,并用改进的分段Tent映射分别对幅值和位相进行置乱处理;其次,将置乱后图像频率域进行傅里叶逆变换,转换成空间域,获得置乱加密图像;最后,利用改进的Ber-noulli移位映射对置乱加密图像进行扩散处理。在MATLAB仿真平台上,实验结果表明:该算法高度安全,密钥空间大,有较强的密钥敏感性能,有效地提高了抵御选择明文攻击的能力。%Frequency domain encryption very fits most of digital and optical image processing systems,while spatial domain encryption is applicable for image communications.In order to make full use of image encryption advantages in both frequency domain and spatial domain and further improve the security of image encryption system,we propose an image encryption algorithm which is based on discrete Fourier transformation and doubling chaotic map to encrypt frequency and spatial domains of image simultaneously.Firstly,the two-dimensional discrete Fourier transformation is committed to convert the image from the spatial domain to frequency domain,and the improved subsection Tent map is used to scramble the amplitude and phase of the frequency domain respectively;Secondly,the frequency domain of scrambled image is transformed into spatial domain with Fourier inverse transformation to get scrambling encryption image;Finally,the improved Bernoulli displacement map is applied to the scrambling encryption image for diffusion processing.The proposed algorithm is tested on MATLAB simulation platform

  17. Encryption-Decryption RGB Color Image Using Matrix Multiplication

    Mohamad M.AL-Laham

    2015-01-01

    An enhanced technique of color image encryption based on random matrix key encoding is proposed. To encrypt the color image a separation into Red Green and Blue (R, G, B) channels will applied. Each channel is encrypted using a technique called double random matrix key encoding then three new coding image matrices are constructed. To obtain the reconstructed image that is the same as the original image in the receipted side; simple extracted and decryption operations can be mainta...

  18. Symmetric encryption algorithms using chaotic and non-chaotic generators: A review.

    Radwan, Ahmed G; AbdElHaleem, Sherif H; Abd-El-Hafiz, Salwa K

    2016-03-01

    This paper summarizes the symmetric image encryption results of 27 different algorithms, which include substitution-only, permutation-only or both phases. The cores of these algorithms are based on several discrete chaotic maps (Arnold's cat map and a combination of three generalized maps), one continuous chaotic system (Lorenz) and two non-chaotic generators (fractals and chess-based algorithms). Each algorithm has been analyzed by the correlation coefficients between pixels (horizontal, vertical and diagonal), differential attack measures, Mean Square Error (MSE), entropy, sensitivity analyses and the 15 standard tests of the National Institute of Standards and Technology (NIST) SP-800-22 statistical suite. The analyzed algorithms include a set of new image encryption algorithms based on non-chaotic generators, either using substitution only (using fractals) and permutation only (chess-based) or both. Moreover, two different permutation scenarios are presented where the permutation-phase has or does not have a relationship with the input image through an ON/OFF switch. Different encryption-key lengths and complexities are provided from short to long key to persist brute-force attacks. In addition, sensitivities of those different techniques to a one bit change in the input parameters of the substitution key as well as the permutation key are assessed. Finally, a comparative discussion of this work versus many recent research with respect to the used generators, type of encryption, and analyses is presented to highlight the strengths and added contribution of this paper. PMID:26966561

  19. Symmetric encryption algorithms using chaotic and non-chaotic generators: A review

    Radwan, Ahmed G.; AbdElHaleem, Sherif H.; Abd-El-Hafiz, Salwa K.

    2015-01-01

    This paper summarizes the symmetric image encryption results of 27 different algorithms, which include substitution-only, permutation-only or both phases. The cores of these algorithms are based on several discrete chaotic maps (Arnold’s cat map and a combination of three generalized maps), one continuous chaotic system (Lorenz) and two non-chaotic generators (fractals and chess-based algorithms). Each algorithm has been analyzed by the correlation coefficients between pixels (horizontal, vertical and diagonal), differential attack measures, Mean Square Error (MSE), entropy, sensitivity analyses and the 15 standard tests of the National Institute of Standards and Technology (NIST) SP-800-22 statistical suite. The analyzed algorithms include a set of new image encryption algorithms based on non-chaotic generators, either using substitution only (using fractals) and permutation only (chess-based) or both. Moreover, two different permutation scenarios are presented where the permutation-phase has or does not have a relationship with the input image through an ON/OFF switch. Different encryption-key lengths and complexities are provided from short to long key to persist brute-force attacks. In addition, sensitivities of those different techniques to a one bit change in the input parameters of the substitution key as well as the permutation key are assessed. Finally, a comparative discussion of this work versus many recent research with respect to the used generators, type of encryption, and analyses is presented to highlight the strengths and added contribution of this paper. PMID:26966561

  20. AN ENCRYPTION ALGORITHM FOR IMPROVING DATABASE SECURITY USING ROT & REA

    M. Sujitha

    2015-06-01

    Full Text Available Database is an organized collection of data, many user wants to store their personal and confidential data’s in such database. Unauthorized persons may try to get the data’s from database and misuse them without the owner’s knowledge. To overcome such problem the advanced control mechanism, known as Database security was introduced. Encryption algorithm is one of the way to give protection to the database from various threat or hackers who target to get confidential information. This paper discuss about the proposed encryption algorithm to give security to such database.

  1. Radial Hilbert Transform in terms of the Fourier Transform applied to Image Encryption

    In the present investigation, a mathematical algorithm under Matlab platform using Radial Hilbert Transform and Random Phase Mask for encrypting digital images is implemented. The algorithm is based on the use of the conventional Fourier transform and two random phase masks, which provide security and robustness to the system implemented. Random phase masks used during encryption and decryption are the keys to improve security and make the system immune to attacks by program generation phase masks

  2. Digital Image Encryption Based On Multiple Chaotic Maps

    Amir Houshang Arab Avval

    2016-01-01

    Full Text Available A novel and robust chaos-based digital image encryption is proposed. The present paper presents a cipher block image encryption using multiple chaotic maps to lead increased security. An image block is encrypted by the block-based permutation process and cipher block encryption process. In the proposed scheme, secret key includes nineteen control and initial conditions parameter of the four chaotic maps and the calculated key space is 2883. The effectiveness and security of the proposed encryption scheme has been performed using the histograms, correlation coefficients, information entropy, differential analysis, key space analysis, etc. It can be concluded that the proposed image encryption technique is a suitable choice for practical applications.

  3. Selective Encryption of Human Skin in JPEG Images

    Rodrigues, José; Puech, William; Bors, Adrian,

    2006-01-01

    International audience In this study we propose a new approach for selective encryption in the Huffman coding of the Discrete Cosine Transform (DCT) coefficients using the Advanced Encryption Standard (AES). The objective is to partially encrypt the human face in an image or video sequence. This approach is based on the AES stream ciphering using Variable Length Coding (VLC) of the Huffman's vector. The proposed scheme allows the decryption of a specific region of the image and results in ...

  4. Analysis of cipher text size produced by various Encryption Algorithms

    MANI ARORA

    2011-07-01

    Full Text Available In the digital world, it is the need of the hour to secure the data communication from unauthorized access. Over the time a number of techniques and algorithms have came into operation for its security. This research paper is done qualitatively to emphasize the need for securing the data as well as the fast transmission of the encryptedtext. It concerns the analysis of selected symmetric cipher block encryption algorithms from cipher text size point of view.

  5. Overview on Selective Encryption of Image and Video: Challenges and Perspectives

    Massoudi A; Lefebvre F; De Vleeschouwer C; Macq B; Quisquater J-J

    2008-01-01

    In traditional image and video content protection schemes, called fully layered, the whole content is first compressed. Then, the compressed bitstream is entirely encrypted using a standard cipher (DES, AES, IDEA, etc.). The specific characteristics of this kind of data (high-transmission rate with limited bandwidth) make standard encryption algorithms inadequate. Another limitation of fully layered systems consists of altering the whole bitstream syntax which may disable some codec function...

  6. Exploiting root-mean-square time-frequency structure for multiple-image optical compression and encryption

    Alfalou, Ayman; Brosseau, C.

    2010-01-01

    International audience We report on a new algorithm to compress and encrypt simultaneously multiple images (target images). This method, which is based upon a specific spectral multiplexing (fusion without overlapping) of the multiple images, aims to achieve a single encrypted image, at the output plane of our system, that contains all information needed to reconstruct the target images. For that purpose, we divide the Fourier plane of the image to transmit into two types of area, i.e., sp...

  7. Application of Cosine Zone Plates to Image Encryption

    GE Fan; CHEN Lin-Fei; ZHAO Dao-Mu

    2008-01-01

    @@ We analyse the diffraction result of optical field after Cosine zone plate, and theoretically deduce its transform matrix. Under some conditions, its diffraction distribution is a mixture of fractional Fourier spectra. Then we use Cosine zone plate and its diffraction result to image encryption. Possible optical image encryption and decryption implementations are proposed, and some numerical simulation results are also provided.

  8. A joint encryption/watermarking system for verifying the reliability of medical images.

    Bouslimi, Dalel; Coatrieux, Gouenou; Cozic, Michel; Roux, Christian

    2012-09-01

    In this paper, we propose a joint encryption/water-marking system for the purpose of protecting medical images. This system is based on an approach which combines a substitutive watermarking algorithm, the quantization index modulation, with an encryption algorithm: a stream cipher algorithm (e.g., the RC4) or a block cipher algorithm (e.g., the AES in cipher block chaining (CBC) mode of operation). Our objective is to give access to the outcomes of the image integrity and of its origin even though the image is stored encrypted. If watermarking and encryption are conducted jointly at the protection stage, watermark extraction and decryption can be applied independently. The security analysis of our scheme and experimental results achieved on 8-bit depth ultrasound images as well as on 16-bit encoded positron emission tomography images demonstrate the capability of our system to securely make available security attributes in both spatial and encrypted domains while minimizing image distortion. Furthermore, by making use of the AES block cipher in CBC mode, the proposed system is compliant with or transparent to the DICOM standard. PMID:22801525

  9. A Secure Network Communication Protocol Based on Text to Barcode Encryption Algorithm

    Abusukhon Ahmad

    2015-12-01

    Full Text Available Nowadays, after the significant development in the Internet, communication and information exchange around the world has become easier and faster than before. One may send an e-mail or perform money transaction (using a credit card while being at home. The Internet users can also share resources (storage, memory, etc. or invoke a method on a remote machine. All these activities require securing data while the data are sent through the global network. There are various methods for securing data on the internet and ensuring its privacy; one of these methods is data encryption. This technique is used to protect the data from hackers by scrambling these data into a non-readable form. In this paper, we propose a novel method for data encryption based on the transformation of a text message into a barcode image. In this paper, the proposed Bar Code Encryption Algorithm (BCEA is tested and analyzed.

  10. A fast chaotic block cipher for image encryption

    Armand Eyebe Fouda, J. S.; Yves Effa, J.; Sabat, Samrat L.; Ali, Maaruf

    2014-03-01

    Image encryption schemes based on chaos usually involve real number arithmetic operations to generate the chaotic orbits from the chaotic system. These operations are time-consuming and are normally performed with high-end processors. To overcome this drawback, this paper proposes a one round encryption scheme for the fast generation of large permutation and diffusion keys based on the sorting of the solutions of the Linear Diophantine Equation (LDE) whose coefficients are integers and dynamically generated from any type of chaotic systems. The high security and low computational complexity are achieved not only by using large permutation based on the sorting of the solutions of LDE but also by generating only one permutation from the sorting of the solutions of the LDE, then by dynamically updating d number of integers (d>2) in the permutation. The performance of the proposed scheme is evaluated using various types of analysis such as entropy analysis, difference analysis, statistical analysis, key sensitivity analysis, key space analysis and speed analysis. The experimental results indicate that the proposed algorithm is secure and fast as compared to the two round encryption scheme.

  11. Multiple-image encryption based on compressive holography using a multiple-beam interferometer

    Wan, Yuhong; Wu, Fan; Yang, Jinghuan; Man, Tianlong

    2015-05-01

    Multiple-image encryption techniques not only improve the encryption capacity but also facilitate the transmission and storage of the ciphertext. We present a new method of multiple-image encryption based on compressive holography with enhanced data security using a multiple-beam interferometer. By modifying the Mach-Zehnder interferometer, the interference of multiple object beams and unique reference beam is implemented for encrypting multiple images simultaneously into one hologram. The original images modulated with the random phase masks are put in different positions with different distance away from the CCD camera. Each image plays the role of secret key for other images to realize the mutual encryption. Four-step phase shifting technique is combined with the holographic recording. The holographic recording is treated as a compressive sensing process, thus the decryption process is inverted as a minimization problem and the two-step iterative shrinkage/thresholding algorithm (TwIST) is employed to solve this optimization problem. The simulated results about multiple binary and grayscale images encryption are demonstrated to verify the validity and robustness of our proposed method.

  12. Encrypting three-dimensional information system based on integral imaging and multiple chaotic maps

    Xing, Yan; Wang, Qiong-Hua; Xiong, Zhao-Long; Deng, Huan

    2016-02-01

    An encrypting three-dimensional (3-D) information system based on integral imaging (II) and multiple chaotic maps is proposed. In the encrypting process, the elemental image array (EIA) which represents spatial and angular information of the real 3-D scene is picked up by a microlens array. Subsequently, R, G, and B color components decomposed by the EIA are encrypted using multiple chaotic maps. Finally, these three encrypted components are interwoven to obtain the cipher information. The decryption process implements the reverse operation of the encryption process for retrieving the high-quality 3-D images. Since the encrypted EIA has the data redundancy property due to II, and all parameters of the pickup part are the secret keys of the encrypting system, the system sensitivity on the changes of the plaintext and secret keys can be significantly improved. Moreover, the algorithm based on multiple chaotic maps can effectively enhance the security. A preliminary experiment is carried out, and the experimental results verify the effectiveness, robustness, and security of the proposed system.

  13. A one-time one-key encryption algorithm based on the ergodicity of chaos

    In this paper, we propose a new one-time one-key encryption algorithm based on the ergodicity of a skew tent chaotic map. We divide the chaotic trajectory into sub-intervals and map them to integers, and use this scheme to encrypt plaintext and obtain ciphertext. In this algorithm, the plaintext information in the key is used, so different plaintexts or different total numbers of plaintext letters will encrypt different ciphertexts. Simulation results show that the performance and the security of the proposed encryption algorithm can encrypt plaintext effectively and resist various typical attacks. (general)

  14. Bi-serial DNA Encryption Algorithm(BDEA)

    Prabhu, D

    2011-01-01

    The vast parallelism, exceptional energy efficiency and extraordinary information inherent in DNA molecules are being explored for computing, data storage and cryptography. DNA cryptography is a emerging field of cryptography. In this paper a novel encryption algorithm is devised based on number conversion, DNA digital coding, PCR amplification, which can effectively prevent attack. Data treatment is used to transform the plain text into cipher text which provides excellent security

  15. Efficient Hardware Implementation of the Lightweight Block Encryption Algorithm LEA

    Donggeon Lee; Dong-Chan Kim; Daesung Kwon; Howon Kim

    2014-01-01

    Recently, due to the advent of resource-constrained trends, such as smartphones and smart devices, the computing environment is changing. Because our daily life is deeply intertwined with ubiquitous networks, the importance of security is growing. A lightweight encryption algorithm is essential for secure communication between these kinds of resource-constrained devices, and many researchers have been investigating this field. Recently, a lightweight block cipher called LEA was proposed. LEA ...

  16. Micro-lens array based 3-D color image encryption using the combination of gravity model and Arnold transform

    You, Suping; Lu, Yucheng; Zhang, Wei; Yang, Bo; Peng, Runling; Zhuang, Songlin

    2015-11-01

    This paper proposes a 3-D image encryption scheme based on micro-lens array. The 3-D image can be reconstructed by applying the digital refocusing algorithm to the picked-up light field. To improve the security of the cryptosystem, the Arnold transform and the Gravity Model based image encryption method are employed. Experiment results demonstrate the high security in key space of the proposed encryption scheme. The results also indicate that the employment of light field imaging significant strengthens the robustness of the cipher image against some conventional image processing attacks.

  17. A pipelined FPGA implementation of an encryption algorithm based on genetic algorithm

    Thirer, Nonel

    2013-05-01

    With the evolution of digital data storage and exchange, it is essential to protect the confidential information from every unauthorized access. High performance encryption algorithms were developed and implemented by software and hardware. Also many methods to attack the cipher text were developed. In the last years, the genetic algorithm has gained much interest in cryptanalysis of cipher texts and also in encryption ciphers. This paper analyses the possibility to use the genetic algorithm as a multiple key sequence generator for an AES (Advanced Encryption Standard) cryptographic system, and also to use a three stages pipeline (with four main blocks: Input data, AES Core, Key generator, Output data) to provide a fast encryption and storage/transmission of a large amount of data.

  18. Quantum image encryption based on generalized affine transform and logistic map

    Liang, Hao-Ran; Tao, Xiang-Yang; Zhou, Nan-Run

    2016-07-01

    Quantum circuits of the generalized affine transform are devised based on the novel enhanced quantum representation of digital images. A novel quantum image encryption algorithm combining the generalized affine transform with logistic map is suggested. The gray-level information of the quantum image is encrypted by the XOR operation with a key generator controlled by the logistic map, while the position information of the quantum image is encoded by the generalized affine transform. The encryption keys include the independent control parameters used in the generalized affine transform and the logistic map. Thus, the key space is large enough to frustrate the possible brute-force attack. Numerical simulations and analyses indicate that the proposed algorithm is realizable, robust and has a better performance than its classical counterpart in terms of computational complexity.

  19. Quantum image encryption based on generalized affine transform and logistic map

    Liang, Hao-Ran; Tao, Xiang-Yang; Zhou, Nan-Run

    2016-03-01

    Quantum circuits of the generalized affine transform are devised based on the novel enhanced quantum representation of digital images. A novel quantum image encryption algorithm combining the generalized affine transform with logistic map is suggested. The gray-level information of the quantum image is encrypted by the XOR operation with a key generator controlled by the logistic map, while the position information of the quantum image is encoded by the generalized affine transform. The encryption keys include the independent control parameters used in the generalized affine transform and the logistic map. Thus, the key space is large enough to frustrate the possible brute-force attack. Numerical simulations and analyses indicate that the proposed algorithm is realizable, robust and has a better performance than its classical counterpart in terms of computational complexity.

  20. Optical color-image encryption in the diffractive-imaging scheme

    Qin, Yi; Wang, Zhipeng; Pan, Qunna; Gong, Qiong

    2016-02-01

    By introducing the theta modulation technique into the diffractive-imaging-based optical scheme, we propose a novel approach for color image encryption. For encryption, a color image is divided into three channels, i.e., red, green and blue, and thereafter these components are appended by redundant data before being sent to the encryption scheme. The carefully designed optical setup, which comprises of three 4f optical architectures and a diffractive-imaging-based optical scheme, could encode the three plaintexts into a single noise-like intensity pattern. For the decryption, an iterative phase retrieval algorithm, together with a filter operation, is applied to extract the primary color images from the diffraction intensity map. Compared with previous methods, our proposal has successfully encrypted a color rather than grayscale image into a single intensity pattern, as a result of which the capacity and practicability have been remarkably enhanced. In addition, the performance and the security of it are also investigated. The validity as well as feasibility of the proposed method is supported by numerical simulations.

  1. Novel Image Encryption Scheme Based on Chebyshev Polynomial and Duffing Map

    2014-01-01

    We present a novel image encryption algorithm using Chebyshev polynomial based on permutation and substitution and Duffing map based on substitution. Comprehensive security analysis has been performed on the designed scheme using key space analysis, visual testing, histogram analysis, information entropy calculation, correlation coefficient analysis, differential analysis, key sensitivity test, and speed test. The study demonstrates that the proposed image encryption algorithm shows advantages of more than 10113 key space and desirable level of security based on the good statistical results and theoretical arguments. PMID:25143970

  2. Color Satellite Image Encryption Algorithm Based on Improved Generalized Cat Mapping%基于改进广义cat映射的彩色卫星图像加密算法

    2015-01-01

    In order to improve encryption effect of color satellite image,in this paper,a color satellite image encryption algorithm based on improved generalized cat map is proposed; the idea of constructing the generalized cat mapping is used in this algorithm. The transformation of the corresponding first transform expression of discrete generalized cat mapping of the nonlinear transform into second, three color components of color images were three scrambled by using the improved generalized cat mapping; then the diffusion for scrambled image is carried out by using compound chaos mapping. Theoretical analysis and simulation results show that the algorithm can improve encryption effect of the image;it has a large space with a secret key,anti-statistical attack,good performance and strong sensitivity of the secret key and can achieve the appropriate level of safety.%为了提高彩色卫星图像的加密效果,提出了一种基于改进广义cat映射的彩色卫星图像加密算法。该算法利用广义cat映射的构造思想,将离散广义cat映射的第一个变换表达式所对应的变换结果非线性的融入第二个变换表达式,利用改进广义cat映射对彩色卫星图像的三个色彩分量分别进行三轮置乱,然后利用复合混沌映射对置乱后的图像进行扩散。经过理论分析和仿真实验检测,该算法可以更好的改善图像的加密效果,具有密钥空间大、抗统计攻击能力强、密钥敏感性强等良好的性能,能够达到相应的安全水平。

  3. Security Improvement of an Image Encryption Based on mPixel-Chaotic-Shuffle and Pixel-Chaotic-Diffusion

    Ahmad, Musheer; Alsharari, Hamed D.; Nizam, Munazza

    2014-01-01

    In this paper, we propose to improve the security performance of a recently proposed color image encryption algorithm which is based on multi-chaotic systems. The existing cryptosystem employed a pixel-chaotic-shuffle mechanism to encrypt images, in which the generation of shuffling sequences are independent to the plain-image/cipher-image. As a result, it fails to the chosen-plaintext and known-plaintext attacks. Moreover, the statistical features of the cryptosystem are not up to the standa...

  4. Plaintext Related Image Encryption Scheme Using Chaotic Map

    Yong Zhang

    2013-07-01

    Full Text Available A plaintext related image blocking encryption algorithm is proposed in this paper, which includes two kinds of operations on inner-block confusion and inter-block diffusion. Firstly, a float-point lookup table need to be generated by iterating chaotic system; Secondly, choose one of the entries in the look-up table as initial value of chaotic system, and iterate it to produce one secret code sequence for inner-block confusion; Thirdly, by using one pixel value of the former block to locate another entry in the look-up table, iterate it to yield another secret code sequence for inter-block diffusion; Finally, through two rounds of the block-by-block processes, the plain-image will be transformed into the cipher-image. The simulation results show that the proposed method has many good characters.

  5. Encryption-Decryption RGB Color Image Using Matrix Multiplication

    Mohamad M.AL-Laham

    2015-10-01

    Full Text Available An enhanced technique of color image encryption based on random matrix key encoding is proposed. To encrypt the color image a separation into Red Green and Blue (R, G, B channels will applied. Each channel is encrypted using a technique called double random matrix key encoding then three new coding image matrices are constructed. To obtain the reconstructed image that is the same as the original image in the receipted side; simple extracted and decryption operations can be maintained. The results shown that the proposed technique is powerful for color image encryption and decryption and a MATLAB and simulations were used to get the results. The proposed technique has high security features because each color component is separately treated using its own double random matrix key which is generated randomly and make the process of hacking the three keys very difficult

  6. SYMMETRIC ENCRYPTION ALGORITHM IN SPEECH CODING FOR DEFENCE COMMUNICATIONS

    Akella Amarendra Babu

    2012-01-01

    Full Text Available In battlefield, messages must be encrypted to provide protection from enemy interception. Several speech coding algorithms have been developed to provide secure communications. FS1015 LPC in 1984, FS1016 CELP in 1991and FS MELP in 1997 became official federal standards. In 2002, the US DoD adopted enhanced MELP (MELPe. Later on in 2007, US Naval Research Laboratories have designed Variable Data Rate (VDR voice processor. Although certain degree of inherent security is ensured in all the above coding algorithms by way of compression techniques, strength of security in these algorithms is weak as the codecs using the above algorithms are vulnerable to interception. Explicit encryption gadgets need to be provided as accessory to provide strong secure communications. In this paper, we have described an algorithm which provides robust and secure communications. This Robust Secure Coder (RSC is backward compatible with the existing codec’s and operates at marginally higher bit rates when switched to secure mode.

  7. Devil’s Vortex Phase Structure as Frequency Plane Mask for Image Encryption Using the Fractional Mellin Transform

    Sunanda Vashisth

    2014-01-01

    Full Text Available A frequency plane phase mask based on Devil’s vortex structure has been used for image encryption using the fractional Mellin transform. The phase key for decryption is obtained by an iterative phase retrieval algorithm. The proposed scheme has been validated for grayscale secret target images, by numerical simulation. The efficacy of the scheme has been evaluated by computing mean-squared-error between the secret target image and the decrypted image. Sensitivity analysis of the decryption process to variations in various encryption parameters has been carried out. The proposed encryption scheme has been seen to exhibit reasonable robustness against occlusion attack.

  8. A Technique for Image Encryption with Combination of Pixel Rearrangement Scheme Based On Sorting Group-Wise Of RGB Values and Explosive Inter-Pixel Displacement

    Amnesh Goel

    2012-03-01

    Full Text Available Encryption is used to prevent data from unauthorized access and with the appalling headway in network technology seen in the past decade; it has become the need of time to encrypt the images before sending over open network. Though researchers has proposed contrastive methods to encrypt images but correlation between pixels RGB value play a imperative part to guess for original image. So, here we introduce a new image encryption method which first rearranges the pixels within image on basis of RGB values and then forward intervening image for encryption. Experimentally it has shown that pixel rearrangement is enough from image encryption point of view but to send image over open network; inter-pixel displacement algorithm is applied to dispense more armament to image before transmission.

  9. A recoverable stress testing algorithm for compression and encryption cards

    Bao-jun ZHANG; Xue-zeng PAN; Jie-bing WANG; Ling-di PING

    2008-01-01

    This study proposes a recoverable stress testing algorithm (RSTA) for such special devices as compression/decom-pression card and encryption/decryption card. It uses a chaos function to generate a random sequence, and then, according to the random sequence, generates an effective command sequence. The dispatch of command obeys a special schedule strategy we designed for such devices, I.e., the commands are sent according to the command sequence, and the complete commands are put in a buffer for further result check. RSTA is used to test the HIFN compression acceleration card SAICHI- 1000. Test results show that RSTA can make the card work continuously and adequately.

  10. NEW SYMMETRIC ENCRYPTION SYSTEM BASED ON EVOLUTIONARY ALGORITHM

    A. Mouloudi

    2015-12-01

    Full Text Available In this article, we present a new symmetric encryption system which is a combination of our ciphering evolutionary system SEC [1] and a new ciphering method called “fragmentation”. This latter allows the alteration of the appearance frequencies of characters from a given text. Our system has at its disposed two keys, the first one is generated by the evolutionary algorithm, the second one is generated after “fragmentation” part. Both of them are symmetric, session keys and strengthening the security of our system.

  11. Content-based image retrieval in homomorphic encryption domain.

    Bellafqira, Reda; Coatrieux, Gouenou; Bouslimi, Dalel; Quellec, Gwenole

    2015-08-01

    In this paper, we propose a secure implementation of a content-based image retrieval (CBIR) method that makes possible diagnosis aid systems to work in externalized environment and with outsourced data as in cloud computing. This one works with homomorphic encrypted images from which it extracts wavelet based image features next used for subsequent image comparison. By doing so, our system allows a physician to retrieve the most similar images to a query image in an outsourced database while preserving data confidentiality. Our Secure CBIR is the first one that proposes to work with global image features extracted from encrypted images and does not induce extra communications in-between the client and the server. Experimental results show it achieves retrieval performance as good as if images were processed non-encrypted. PMID:26736909

  12. Secure Reversible Data Hiding in Encrypted Images by Allocating Memory before Encryption via Security keys

    Priya Jambhulkar; Pardhi, P R

    2015-01-01

    Digital image and information embedding system have number of important multimedia applications. Recently, attention is paid to reversible data hiding (RDH) in encrypted images is more, since it maintains the excellent property that the original cover can be lossless recovered after embedded data is extracted while protecting the image content’s confidentiality. RDH is a technique used to hide data inside image for high security in such a way that original data is not visible. All previous me...

  13. ecure Reversible Data Hiding in Encrypted Images by Allocating Memory before Encryption via Security keys

    Priya Jambhulkar; Pardhi, P R

    2014-01-01

    Digital image and information embedding system have number of important multimedia applications. Recently, attention is paid to reversible data hiding (RDH) in encrypted images is more, since it maintains the excellent property that the original cover can be lossless recovered after embedded data is extracted while protecting the image content’s confidentiality. RDH is a technique used to hide data inside image for high security in such a way that original data is not visible....

  14. Application of the Chaotic Ergodicity of Standard Map in Image Encryption and Watermarking

    Ruisong Ye; Huiqing Huang

    2010-01-01

    Thanks to the exceptionally good properties in chaotic systems, such as sensitivity to initial conditions and control parameters, pseudo-randomness and ergodicity, chaos-based image encryption algorithms have been widely studied and developed in recent years. Standard map is chaotic so that it can be employed to shuffle the positions of image pixels to get a totally visual difference from the original images. This paper proposes two novel schemes to shuffle digital images. Different from the ...

  15. Advanced Steganography Algorithm Using Randomized Intermediate QR Host Embedded With Any Encrypted Secret Message: ASA_QR Algorithm

    Somdip Dey

    2012-06-01

    Full Text Available Due to tremendous growth in communication technology, now it is a real problem / challenge to send some confidential data / information through communication network. For this reason, Nath et al. developed several information security systems, combining cryptography and steganography together, and the present method, ASA_QR, is also one of them. In the present paper, the authors present a new steganography algorithm to hide any small encrypted secret message inside QR CodeTM , which is then randomized and then, finally embed that randomized QR Code inside some common image. Quick Response Codes (or QR Codes are a type of two-dimensional matrix barcodes used for encoding information. It has become very popular recently for its high storage capacity. The present method is ASA_QR is a combination of strong encryption algorithm and data hiding in two stages to make the entire process extremely hard to break. Here, the secret message is encrypted first and hide it in a QR CodeTM and then again that QR CodeTM is embed in a cover file (picture file in random manner, using the standard method of steganography. In this way the data, which is secured, is almost impossible to be retrieved without knowing the cryptography key, steganography password and the exact unhide method. For encrypting data The authors used a method developed by Nath et al i.e. TTJSA, which is based on generalized modified Vernam Cipher, MSA and NJJSA method; and from the cryptanalysis it is seen that TTJSA is free from any standard cryptographic attacks, like differential attack, plain-text attack or any brute force attack. After encrypting the data using TTJSA,the authors have used standard steganographic method To hide data inside some host file. The present method may be used for sharing secret key, password, digital signature etc.

  16. Chaotic Image Encryption Based on Running-Key Related to Plaintext

    Cao Guanghui

    2014-01-01

    Full Text Available In the field of chaotic image encryption, the algorithm based on correlating key with plaintext has become a new developing direction. However, for this kind of algorithm, some shortcomings in resistance to reconstruction attack, efficient utilization of chaotic resource, and reducing dynamical degradation of digital chaos are found. In order to solve these problems and further enhance the security of encryption algorithm, based on disturbance and feedback mechanism, we present a new image encryption scheme. In the running-key generation stage, by successively disturbing chaotic stream with cipher-text, the relation of running-key to plaintext is established, reconstruction attack is avoided, effective use of chaotic resource is guaranteed, and dynamical degradation of digital chaos is minimized. In the image encryption stage, by introducing random-feedback mechanism, the difficulty of breaking this scheme is increased. Comparing with the-state-of-the-art algorithms, our scheme exhibits good properties such as large key space, long key period, and extreme sensitivity to the initial key and plaintext. Therefore, it can resist brute-force, reconstruction attack, and differential attack.

  17. Chaotic Image Encryption Based on Running-Key Related to Plaintext

    Guanghui, Cao; Kai, Hu; Yizhi, Zhang; Jun, Zhou; Xing, Zhang

    2014-01-01

    In the field of chaotic image encryption, the algorithm based on correlating key with plaintext has become a new developing direction. However, for this kind of algorithm, some shortcomings in resistance to reconstruction attack, efficient utilization of chaotic resource, and reducing dynamical degradation of digital chaos are found. In order to solve these problems and further enhance the security of encryption algorithm, based on disturbance and feedback mechanism, we present a new image encryption scheme. In the running-key generation stage, by successively disturbing chaotic stream with cipher-text, the relation of running-key to plaintext is established, reconstruction attack is avoided, effective use of chaotic resource is guaranteed, and dynamical degradation of digital chaos is minimized. In the image encryption stage, by introducing random-feedback mechanism, the difficulty of breaking this scheme is increased. Comparing with the-state-of-the-art algorithms, our scheme exhibits good properties such as large key space, long key period, and extreme sensitivity to the initial key and plaintext. Therefore, it can resist brute-force, reconstruction attack, and differential attack. PMID:24711727

  18. High security and robust optical image encryption approach based on computer-generated integral imaging pickup and iterative back-projection techniques

    Li, Xiao Wei; Cho, Sung Jin; Kim, Seok Tae

    2014-04-01

    In this paper, a novel optical image encryption algorithm by combining the use of computer-generated integral imaging (CGII) pickup technique and iterative back-projection (IBP) technique is proposed. In this scheme, a color image to be encrypted which is firstly segregated into three channels: red, green, and blue. Each of these three channels is independently captured by using a virtual pinhole array and be computationally transformed as a sub-image array. Then, each of these three sub-image arrays are scrambled by the Fibonacci transformation (FT) algorithm, respectively. These three scrambled sub-image arrays are encrypted by the hybrid cellular automata (HCA), respectively. Ultimately, these three encrypted images are combined to produce the colored encrypted image. In the reconstruction process, because the computational integral imaging reconstruction (CIIR) is a pixel-overlapping reconstruction technique, the interference of the adjacent pixels will decrease the quality of the reconstructed image. To address this problem, we introduce an image super-resolution reconstruction technique, the image can be computationally reconstructed by the IBP technique. Some numerical simulations are made to test the validity and the capability of the proposed image encryption algorithm.

  19. Fractional Hartley transform applied to optical image encryption

    Jimenez, C [Grupo GIFES. Universidad de La Guajira. Riohacha (Colombia); Torres, C; Mattos, L, E-mail: carlosj114@gmail.com [Grupo LOI. Universidad Popular del Cesar. Valledupar (Colombia)

    2011-01-01

    A new method for image encryption is introduced on the basis of two-dimensional (2-D) generalization of 1-D fractional Hartley transform that has been redefined recently in search of its inverse transform We encrypt the image by two fractional orders and random phase codes. It has an advantage over Hartley transform, for its fractional orders can also be used as addictional keys, and that, of course, strengthens image security. Only when all of these keys are correct, can the image be well decrypted. Computer simulations are also perfomed to confirm the possibility of proposed method.

  20. Improving Security of Parallel Algorithm Using Key Encryption Technique

    R. Swarna Raja

    2013-01-01

    Full Text Available In the recent cloud era, computing moves to a new plane of running large scale scientific applications. Many parallel algorithms have been created to support a large dataset. MapReduce is one such parallel data processing framework adopted widely for scientific research, machine learning and high end computing. The most prevalent implementation of MapReduce is the open source project Hadoop. To protect the integrity and confidentiality of data uploaded, MapReduce introduced a Kerberos-based model with tokens for datablocks and processing nodes. The tokens are symmetrically encrypted and distributed across the nodes. Such a technique is vulnerable to man-in-the-middle attacks like data loss, data modification and stealing of keys. In this study, a novel technique is proposed based on public key encryption on top of the Kerberos model to enhance Security. The various attack scenarios on the current Hadoop implementation model has been analyzed and a secure environment has been proposed. The study shows that the proposed framework provides an improved level of security when using RSA (Rivest Shamir Adleman with 65,537 keysize consumed 23 milli seconds, while using 257 bits keysize which consumed 21 milli seconds.

  1. Exploring an Effective Digital Image Encryption Algorithm Based on Stream Cipher and Genetic Algorithm (GA)%一种基于流密码和遗传算法的高效数字图像加密算法探索

    牛振喜

    2011-01-01

    Aim. The introduction of the full paper reviews some relevant matters and then proposes the exploration mentioned in the title, whose result we believe is effective and appears to have a promising future in the encryption field and is fully explained in sections 1 and 2. Their core consists of; "We propose a color digital image encryption algorithm based on the advantages of stream cipher and GA. Firstly, the algorithm divides the image into blocks; then it uses XOR operation to alter the pixel value in each block; next, it exerts different three - dimensional Arnold transforms, which are based on different times of iterations and transformation matrixes, on the different color components; finally, it encrypts the image by applying XOR operation to the image data and the key stream (generated by GA). " Section 2 is entitled "Analysis of Security of Algorithm". Subsection 2. 1 deals with the theoretical analysis of the security of algorithm. Subsection 2. 2 deals with experimental results, presented in Figs. 3 through 12 and Tables 1 and 2, and their analysis. Theoretical analysis and numerical experiments show preliminarily that the algorithm is excellent with large key space, high key sensibility, satisfactory encryption, and being able to resist common attacks effectively.%本文结合流密码和遗传算法的优点,提出了一种彩色数字图像加密算法.该算法首先将图像分块,各块内象素相互异或,再对不同颜色分量执行迭代次数和变换矩阵均不同的三维Arnold变换,最后将遗传算法产生的密钥流与图像数据相异或来对图像进行加密.经过理论分析和实验验证,该算法具有密钥空间大、密钥敏感性高,加密效果好、并能有效抵御常见攻击等优点.

  2. Digital Image Encryption: A Survey%数字图像加密综述

    文昌辞; 王沁; 苗晓宁; 刘向宏; 彭阳翔

    2012-01-01

    According to the feature of digital image, the reason why traditional cipher algorithms are not applicable was analyzed,and the development of digital image encryption was surveyed. Some techniques, such as pixel permutation in space domain,encryption based on chaos, encryption in transform domain, image secret segmentation and sharing, encryption based on neutral network and cellular automata,encryption based on blind source separation, were illustrated, and the corresponding characteristics were analyzed and compared. At last, a large number of typical encryption algorithms were analyzed in detail to expose their weakness,and the future research direction was discussed.%针对数字图像的特点,分析了传统加密算法不适用的原因,陈述了数字图像加密的现状,对基于空间域的像素置乱、基于混沌的加密、基于变换域的加密、基于秘密分割与秘密共享的加密、基于神经网络和元胞自动机的加密以及基于盲源分离的加密进行了详细描述,并对它们的特点进行了分析比较.最后,举例分析了大量典型的加密算法,指出了它们的不足,并探讨了进一步的研究方向.

  3. A Comparison between Memetic algorithm and Genetic algorithm for the cryptanalysis of Simplified Data Encryption Standard algorithm

    Garg, Poonam

    2010-01-01

    Genetic algorithms are a population-based Meta heuristics. They have been successfully applied to many optimization problems. However, premature convergence is an inherent characteristic of such classical genetic algorithms that makes them incapable of searching numerous solutions of the problem domain. A memetic algorithm is an extension of the traditional genetic algorithm. It uses a local search technique to reduce the likelihood of the premature convergence. The cryptanalysis of simplified data encryption standard can be formulated as NP-Hard combinatorial problem. In this paper, a comparison between memetic algorithm and genetic algorithm were made in order to investigate the performance for the cryptanalysis on simplified data encryption standard problems(SDES). The methods were tested and various experimental results show that memetic algorithm performs better than the genetic algorithms for such type of NP-Hard combinatorial problem. This paper represents our first effort toward efficient memetic algo...

  4. Chaotic Image Scrambling Algorithm Based on S-DES

    Yu, X Y [College of Measurement-Control Tech and Communications Engineering, Harbin University of Science and Technology, Harbin, 150080 (China); Zhang, J [College of Measurement-Control Tech and Communications Engineering, Harbin University of Science and Technology, Harbin, 150080 (China); Ren, H E [Information and Computer Engineering College, Northeast Forestry University, Harbin, 150000 (China); Xu, G S [College of Measurement-Control Tech and Communications Engineering, Harbin University of Science and Technology, Harbin, 150080 (China); Luo, X Y [College of Measurement-Control Tech and Communications Engineering, Harbin University of Science and Technology, Harbin, 150080 (China)

    2006-10-15

    With the security requirement improvement of the image on the network, some typical image encryption methods can't meet the demands of encryption, such as Arnold cat map and Hilbert transformation. S-DES system can encrypt the input binary flow of image, but the fixed system structure and few keys will still bring some risks. However, the sensitivity of initial value that Logistic chaotic map can be well applied to the system of S-DES, which makes S-DES have larger random and key quantities. A dual image encryption algorithm based on S-DES and Logistic map is proposed. Through Matlab simulation experiments, the key quantities will attain 10{sup 17} and the encryption speed of one image doesn't exceed one second. Compared to traditional methods, it has some merits such as easy to understand, rapid encryption speed, large keys and sensitivity to initial value.

  5. Security Analysis of a Block Encryption Algorithm Based on Dynamic Sequences of Multiple Chaotic Systems

    DU Mao-Kang; HE Bo; WANG Yong

    2011-01-01

    Recently, the cryptosystem based on chaos has attracted much attention. Wang and Yu (Commun. Nonlin. Sci. Numer. Simulat. 14(2009)574) proposed a block encryption algorithm based on dynamic sequences of multiple chaotic systems. We analyze the potential Saws in the algorithm. Then, a chosen-plaintext attack is presented. Some remedial measures are suggested to avoid the flaws effectively. Furthermore, an improved encryption algorithm is proposed to resist the attacks and to keep all the merits of the original cryptosystem.

  6. Optical Image Encryption with Simplified Fractional Hartley Transform

    LI Xin-Xin; ZHAO Dao-Mu

    2008-01-01

    We present a new method for image encryption on the basis of simplified fractional Hartley transform (SFRHT). SFRHT is a real transform as Hartley transform (HT) and furthermore, superior to HT in virtue of the advantage that it can also append fractional orders as additional keys for the purpose of improving the system security to some extent. With this method, one can encrypt an image with an intensity-only medium such as a photographic film or a CCD camera by spatially incoherent or coherent illumination. The optical realization is then proposed and computer simulations are also performed to verify the feasibility of this method.

  7. Multiple-image encryption using spectral cropping and spatial multiplexing

    Deng, Pingke; Diao, Ming; Shan, Mingguang; Zhong, Zhi; Zhang, Yabin

    2016-01-01

    A multiple-image encryption scheme is proposed using spectral cropping and space multiplexing based on discrete multiple-parameter fractional Fourier transform (DMPFRFT). Spectrum of each original image is firstly cropped by a low-pass filter, and the image is then recovered with the same size of the filter. The recovered images are spatially shifted and multiplexed into a complex signal with the same size of original image. The complex signal is multiplied by a pixel scrambling operation and random phase mask, and then encrypted into one image by DMPFRFT. The multiplexing images can be retrieved with correct keys, and the original images can be then obtained by enlarging the demultiplexing images. Numerical simulations have been done to demonstrate the validity and the security of the proposed method.

  8. Double-image encryption based on joint transform correlation and phase-shifting interferometry

    Lina Shen; Jun Li; Hongsen Chang

    2007-01-01

    An image encryption method combining the joint transform correlator (JTC) architecture with phaseshifting interferometry to realize double random-phase encoding is proposed. The encrypted field and the decrypting key are registered as holograms by phase-shifting interferometry. This method can encrypt two images simultaneously to improve the encryption efficiency of the methods based on JTC architecture, and eliminate the system alignment constraint of the methods based on Mach-Zehnder interferometer (MZI)architecture. Its feasibility and validity are verified by computer simulations. Moreover, image encryption and decryption can be achieved at high speed optically or digitally. The encrypted data are suitable for Internet transmission.

  9. Chaos Encryption Algorithm to Deal with Security Threat to Internet of Things RFID

    Tian Xiaoyong

    2013-05-01

    Full Text Available Internet of Things RFID system is mainly studied problem in current communication area, where the safety of code message become rather important. Chaos encryption algorithm can disperse not only the time area but the scale, which is suitable for computer to deal with and overcome the limitation of block encryption in DES and AES. Using Sequence of the digital to deal with initial value and combining the one dimensional Logistic chaos and three dimensional Lorenz algorithm realize common encryption algorithm of these two chaos methods to calculate the long-term random sequence under the limitation of precision and improve the security.

  10. Optical encryption for large-sized images using random phase-free method

    Shimobaba, Tomoyoshi; Kakue, Takashi; Endo, Yutaka; Hirayama, Ryuji; Hiyama, Daisuke; Hasegawa, Satoki; Nagahama, Yuki; Sano, Marie; Sugie, Takashige; Ito, Tomoyoshi

    2015-01-01

    We propose an optical encryption framework that can encrypt and decrypt large-sized images beyond the size of the encrypted image using our two methods: random phase-free method and scaled diffraction. In order to record the entire image information on the encrypted image, the large-sized images require the random phase to widely diffuse the object light over the encrypted image; however, the random phase gives rise to the speckle noise on the decrypted images, and it may be difficult to reco...

  11. Image encryption using random sequence generated from generalized information domain

    Xia-Yan, Zhang; Guo-Ji, Zhang; Xuan, Li; Ya-Zhou, Ren; Jie-Hua, Wu

    2016-05-01

    A novel image encryption method based on the random sequence generated from the generalized information domain and permutation–diffusion architecture is proposed. The random sequence is generated by reconstruction from the generalized information file and discrete trajectory extraction from the data stream. The trajectory address sequence is used to generate a P-box to shuffle the plain image while random sequences are treated as keystreams. A new factor called drift factor is employed to accelerate and enhance the performance of the random sequence generator. An initial value is introduced to make the encryption method an approximately one-time pad. Experimental results show that the random sequences pass the NIST statistical test with a high ratio and extensive analysis demonstrates that the new encryption scheme has superior security.

  12. Efficient image or video encryption based on spatiotemporal chaos system

    In this paper, an efficient image/video encryption scheme is constructed based on spatiotemporal chaos system. The chaotic lattices are used to generate pseudorandom sequences and then encrypt image blocks one by one. By iterating chaotic maps for certain times, the generated pseudorandom sequences obtain high initial-value sensitivity and good randomness. The pseudorandom-bits in each lattice are used to encrypt the Direct Current coefficient (DC) and the signs of the Alternating Current coefficients (ACs). Theoretical analysis and experimental results show that the scheme has good cryptographic security and perceptual security, and it does not affect the compression efficiency apparently. These properties make the scheme a suitable choice for practical applications.

  13. DATA SECURITY IN LOCAL AREA NETWORK BASED ON FAST ENCRYPTION ALGORITHM

    G. Ramesh

    2010-06-01

    Full Text Available Hacking is one of the greatest problems in the wireless local area networks. Many algorithms have been used to prevent the outside attacks to eavesdrop or prevent the data to be transferred to the end-user safely and correctly. In this paper, a new symmetrical encryption algorithm is proposed that prevents the outside attacks. The new algorithm avoids key exchange between users and reduces the time taken for the encryption and decryption. It operates at high data rate in comparison with The Data Encryption Standard (DES, Triple DES (TDES, Advanced Encryption Standard (AES-256, and RC6 algorithms. The new algorithm is applied successfully on both text file and voice message.

  14. A technique for image encryption using digital signature

    Sinha, Aloka; Singh, Kehar

    2003-04-01

    We propose a new technique to encrypt an image for secure image transmission. The digital signature of the original image is added to the encoded version of the original image. The encoding of the image is done using an appropriate error control code, such as a Bose-Chaudhuri Hochquenghem (BCH) code. At the receiver end, after the decryption of the image, the digital signature can be used to verify the authenticity of the image. Detailed simulations have been carried out to test the encryption technique. An optical correlator, in either the JTC or the VanderLugt geometry, or a digital correlation technique, can be used to verify the authenticity of the decrypted image.

  15. Optical asymmetric image encryption using gyrator wavelet transform

    Mehra, Isha; Nishchal, Naveen K.

    2015-11-01

    In this paper, we propose a new optical information processing tool termed as gyrator wavelet transform to secure a fully phase image, based on amplitude- and phase-truncation approach. The gyrator wavelet transform constitutes four basic parameters; gyrator transform order, type and level of mother wavelet, and position of different frequency bands. These parameters are used as encryption keys in addition to the random phase codes to the optical cryptosystem. This tool has also been applied for simultaneous compression and encryption of an image. The system's performance and its sensitivity to the encryption parameters, such as, gyrator transform order, and robustness has also been analyzed. It is expected that this tool will not only update current optical security systems, but may also shed some light on future developments. The computer simulation results demonstrate the abilities of the gyrator wavelet transform as an effective tool, which can be used in various optical information processing applications, including image encryption, and image compression. Also this tool can be applied for securing the color image, multispectral, and three-dimensional images.

  16. Color image single-channel encryption based on tricolor grating theory

    YUAN Qi-ping; YANG Xiao-ping; GAO Li-juan; ZHAI Hong-chen

    2009-01-01

    A method of color image single-channel encryption is proposed. The proposed method uses tricolor grating to encode a color image into a gray level image, then the gray level image is encrypted by double random phase encryption, so a color image is encrypted in a single-channel and its security is ensured. Computer simulations and the chromatic aberration analysis are given to prove the possibility of the proposed idea.The optical system is simpler and is easy to be applied into practice. The simulation results show that this method is efficiency to encrypt a color image, and it is robust.

  17. Hybrid approach for Image Encryption Using SCAN Patterns and Carrier Images

    T, Panduranga H

    2010-01-01

    We propose a hybrid technique for image encryption which employs the concept of carrier image and SCAN patterns generated by SCAN methodology. Although it involves existing method like SCAN methodology, the novelty of the work lies in hybridizing and carrier image creation for encryption. Here the carrier image is created with the help of alphanumeric keyword. Each alphanumeric key will be having a unique 8bit value generated by 4 out of 8-code. This newly generated carrier image is added with original image to obtain encrypted image. The scan methodology is applied to either original image or carrier image, after the addition of original image and carrier image to obtain highly distorted encrypted image. The resulting image is found to be more distorted in hybrid technique. By applying the reverse process we get the decrypted image.

  18. Exploiting root-mean-square time-frequency structure for multiple-image optical compression and encryption.

    Alfalou, A; Brosseau, C

    2010-06-01

    We report on an algorithm to compress and encrypt simultaneously multiple images (target images). This method, which is based upon a specific spectral multiplexing (fusion without overlapping) of the multiple images, aims to achieve a single encrypted image, at the output plane of our system, that contains all information needed to reconstruct the target images. For that purpose, we divide the Fourier plane of the image to transmit into two types of area, i.e., specific and common areas to each target image. A segmentation criterion taking into account the rms duration of each target image spectrum is proposed. This approach, which consists of merging the input target images together (in the Fourier plane) allows us to reduce the information to be stored and/or transmitted (compression) and induce noise on the output image (encryption). To achieve a good encryption level, a first key image (containing biometric information and providing the intellectual property of the target images) is used. A second encryption key is inserted in the Fourier plane to ensure a relevant phase distribution of the different merged spectra. We also discuss how the encoding information can be optimized by minimizing the number of bits required to encode each pixel. PMID:20517460

  19. Efficient Hardware Implementation of the Lightweight Block Encryption Algorithm LEA

    Donggeon Lee

    2014-01-01

    Full Text Available Recently, due to the advent of resource-constrained trends, such as smartphones and smart devices, the computing environment is changing. Because our daily life is deeply intertwined with ubiquitous networks, the importance of security is growing. A lightweight encryption algorithm is essential for secure communication between these kinds of resource-constrained devices, and many researchers have been investigating this field. Recently, a lightweight block cipher called LEA was proposed. LEA was originally targeted for efficient implementation on microprocessors, as it is fast when implemented in software and furthermore, it has a small memory footprint. To reflect on recent technology, all required calculations utilize 32-bit wide operations. In addition, the algorithm is comprised of not complex S-Box-like structures but simple Addition, Rotation, and XOR operations. To the best of our knowledge, this paper is the first report on a comprehensive hardware implementation of LEA. We present various hardware structures and their implementation results according to key sizes. Even though LEA was originally targeted at software efficiency, it also shows high efficiency when implemented as hardware.

  20. Efficient hardware implementation of the lightweight block encryption algorithm LEA.

    Lee, Donggeon; Kim, Dong-Chan; Kwon, Daesung; Kim, Howon

    2014-01-01

    Recently, due to the advent of resource-constrained trends, such as smartphones and smart devices, the computing environment is changing. Because our daily life is deeply intertwined with ubiquitous networks, the importance of security is growing. A lightweight encryption algorithm is essential for secure communication between these kinds of resource-constrained devices, and many researchers have been investigating this field. Recently, a lightweight block cipher called LEA was proposed. LEA was originally targeted for efficient implementation on microprocessors, as it is fast when implemented in software and furthermore, it has a small memory footprint. To reflect on recent technology, all required calculations utilize 32-bit wide operations. In addition, the algorithm is comprised of not complex S-Box-like structures but simple Addition, Rotation, and XOR operations. To the best of our knowledge, this paper is the first report on a comprehensive hardware implementation of LEA. We present various hardware structures and their implementation results according to key sizes. Even though LEA was originally targeted at software efficiency, it also shows high efficiency when implemented as hardware. PMID:24406859

  1. A Color image encryption scheme based on Generalized Synchronization Theorem

    Han shuangshuang

    2013-07-01

    Full Text Available Base on a generalized synchronization theorem (GCS for discrete chaotic system, this paper introduces a new 6-dimensional generalized chaos synchronization system based on 3D-Lorenz map. Numerical simulation showed that two pair variables of the synchronization system achieve generalized synchronization via a transform H.Combining with the 2-Dimension non equilateral Arnold transformation, a color image encryption scheme was designed. Analyzing the key sensitivity, key space, histogram, information entropy and correlation of adjacent pixels, it showed that the scheme have sound encryption and decryption effects. Numerical simulations reveal that the scheme is effective in commercial network communication for its strong anti-interference ability.

  2. Role of Statistical tests in Estimation of the Security of a New Encryption Algorithm

    Krishna, Addepalli V N

    2010-01-01

    Encryption study basically deals with three levels of algorithms. The first algorithm deals with encryption mechanism, second deals with decryption Mechanism and the third discusses about the generation of keys and sub keys used in the encryption study. In the given study, a new algorithm is discussed. The algorithm executes a series of steps and generates a sequence. This sequence is being used as sub key to be mapped to plain text to generate cipher text. The strength of the encryption & Decryption process depends on the strength of sequence generated against crypto analysis.. In this part of work some statistical tests like Uniformity tests, Universal tests & Repetition tests are tried on the sequence generated to test the strength of it.

  3. IMAGE ENCRYPTION TECHNIQUES USING CHAOTIC SCHEMES: A REVIEW

    Monisha Sharma

    2010-06-01

    Full Text Available Cryptography is about communication in the presence of an adversary. It encompasses many problems like encryption, authentication, and key distribution to name a few. The field of modern cryptography providesa theoretical foundation based on which one can understand what exactly these problems are, how to evaluate protocols that purport to solve them and how to build protocols in whose security one can haveconfidence. Advanced digital technologies have made multimedia data widely available. Recently, multimedia applications become common in practice and thus security of multimedia data has become main concern.The basic issues pertaining to the problem of encryption has been discussed and also a survey on image encryption techniques based on chaotic schemes has been dealt in the present communication.The chaotic image encryption can be developed by using properties of chaos including deterministic dynamics, unpredictable behavior and non-linear transform. This concept leads to techniques that can simultaneously provide security functions and an overall visualcheck, which might be suitable in some applications. Digital images are widely used in various applications, that include military, legal and medical systems and these applications need to control access toimages and provide the means to verify integrity of images.

  4. Quantum secret key encryption algorithm based on quantum discrete logarithm problem

    Chen, Chien-Yuan; Hsueh, Chih-Cheng

    2004-01-01

    In this paper, we first define the quantum discrete logarithm problem (QDLP)which is similar to classical discrete logarithm problem. But, this problem cannot be solved by Shor's quantum algorithm. Based on quantum discrete logarithm problem, we present a novel quantum secret key encryption algorithm. The receiver constructs his quantum channel using their secret key. Then, the sender can use the receiver's quantum channel to encrypt the message. Finally, the receiver dencrypts the ciphertext...

  5. Chaos Encryption Algorithm to Deal with Security Threat to Internet of Things RFID

    Tian Xiaoyong

    2013-01-01

    Internet of Things RFID system is mainly studied problem in current communication area, where the safety of code message become rather important. Chaos encryption algorithm can disperse not only the time area but the scale, which is suitable for computer to deal with and overcome the limitation of block encryption in DES and AES. Using Sequence of the digital to deal with initial value and combining the one dimensional Logistic chaos and three dimensional Lorenz algorithm realize common encry...

  6. An Investigation into Encrypted Message Hiding Through Images Using LSB

    FAHIM IRFAN ALAM; FATEHA KHANAM BAPPEE,; FARID UDDIN AHMED KHONDKER

    2011-01-01

    Data security has become a cause of concern because of the electronic spying especially in the military, government and many sectors of communication fields. This paper investigates a representation forembedding secure data within an image based on substitution method which gives the scope of large amount of secret message hiding within digital images. Specifically we used least significant bit (LSB)substitution method to encrypt the message in image file. For improving the performance of LSB...

  7. Dynamic encryption method

    2013-01-01

    Disclosed is a method of transmitting a data set using encryption, wherein the method comprises the steps of: selecting a first encryption technique, wherein said first encryption technique comprises a first encryption algorithm for encrypting plain data into cipher data, and a first decryption...... algorithm for on provision of a specific key, decrypting cipher data and reproduce plain data; encrypting the first data package comprising plain data, using a first encryption program implementing the first encryption algorithm of said first encryption technique, creating a first encrypted data package...

  8. Vector Quantization Techniques For Partial Encryption of Wavelet-based Compressed Digital Images

    H. A. Younis; T. Y. Abdalla; A.Y. Abdalla

    2009-01-01

    The use of image communication has increased in recent years. In this paper, newpartial encryption schemes are used to encrypt only part of the compressed data. Only6.25-25% of the original data is encrypted for four different images, resulting in asignificant reduction in encryption and decryption time. In the compression step, anadvanced clustering analysis technique (Fuzzy C-means (FCM)) is used. In the encryptionstep, the permutation cipher is used. The effect of number of different clust...

  9. Optical image encryption via photon-counting imaging and compressive sensing based ptychography

    Rawat, Nitin; Hwang, In-Chul; Shi, Yishi; Lee, Byung-Geun

    2015-06-01

    In this study, we investigate the integration of compressive sensing (CS) and photon-counting imaging (PCI) techniques with a ptychography-based optical image encryption system. Primarily, the plaintext real-valued image is optically encrypted and recorded via a classical ptychography technique. Further, the sparse-based representations of the original encrypted complex data can be produced by combining CS and PCI techniques with the primary encrypted image. Such a combination takes an advantage of reduced encrypted samples (i.e., linearly projected random compressive complex samples and photon-counted complex samples) that can be exploited to realize optical decryption, which inherently serves as a secret key (i.e., independent to encryption phase keys) and makes an intruder attack futile. In addition to this, recording fewer encrypted samples provides a substantial bandwidth reduction in online transmission. We demonstrate that the fewer sparse-based complex samples have adequate information to realize decryption. To the best of our knowledge, this is the first report on integrating CS and PCI with conventional ptychography-based optical image encryption.

  10. Application of the Chaotic Ergodicity of Standard Map in Image Encryption and Watermarking

    Ruisong Ye

    2010-11-01

    Full Text Available Thanks to the exceptionally good properties in chaotic systems, such as sensitivity to initial conditions and control parameters, pseudo-randomness and ergodicity, chaos-based image encryption algorithms have been widely studied and developed in recent years. Standard map is chaotic so that it can be employed to shuffle the positions of image pixels to get a totally visual difference from the original images. This paper proposes two novel schemes to shuffle digital images. Different from the conventional schemes based on Standard map, we disorder the pixel positions according to the orbits of the Standard map. The proposed shuffling schemes don’t need to discretize the Standard map and own more cipher leys compared with the conventional shuffling scheme based on the discretized Standard map. The shuffling schemes are applied to encrypt image and disorder the host image in watermarking scheme to enhance the robustness against attacks. Experimental results show that the proposed encryption scheme yields good secure effects. The watermarked images are robust against attacks as well.

  11. An efficient diffusion approach for chaos-based image encryption

    One of the existing chaos-based image cryptosystems is composed of alternative substitution and diffusion stages. A multi-dimensional chaotic map is usually employed in the substitution stage for image pixel permutation while a one-dimensional (1D) chaotic map is used for diffusion purpose. As the latter usually involves real number arithmetic operations, the overall encryption speed is limited by the diffusion stage. In this paper, we propose a more efficient diffusion mechanism using simple table lookup and swapping techniques as a light-weight replacement of the 1D chaotic map iteration. Simulation results show that at a similar security level, the proposed cryptosystem needs about one-third the encryption time of a similar cryptosystem. The effective acceleration of chaos-based image cryptosystems is thus achieved.

  12. Partial Encryption of Co mpressed Image Using Threshold Quantization and AES Cipher

    H. A. Younis; A.Y. Abdalla; Y. Abdalla

    2012-01-01

    Cryptography is one of the technological means to provide security to data beingtransmitted on information and communication systems.When it is necessary to securelytransmit data in limited bandwidth, both compression and encryption must be performed.Researchers have combined compression and encryption together to reduce the overallprocessing time.In this paper, new partial encryption schemes are proposed to encrypt only part of thecompressed image.Soft and hard threshold compression methods ...

  13. A Light-weight Symmetric Encryption Algorithm Based on Feistel Cryptosystem Structure

    Jingli Zheng

    2014-12-01

    Full Text Available WSNs is usually deployed in opening wireless environment, its data is easy to be intercepted by attackers. It is necessary to adopt some encryption measurements to protect data of WSNs. But the battery capacity, CPU performance and RAM capacity of WSNs sensors are all limited, the complex encryption algorithm is not fitted for them. The paper proposed a light-level symmetrical encryption algorithm: LWSEA, which adopt minor encryption rounds, shorter data packet and simplified scrambling function. So the calculation cost of LWSEA is very low. We also adopt longer-bit Key and circular interpolation method to produce Child-Key, which raised the security of LWSEA. The experiments demonstrate that the LWSEA possess better "avalanche effect" and data confusion degree, furthermore, its calculation speed is far faster than DES, but its resource cost is very low. Those excellent performances make LWSEA is much suited for resource-restrained WSNs.

  14. A Secure Symmetric Image Encryption Based on Bit-wise Operation

    Prabir Kr. Naskar

    2014-01-01

    Full Text Available This paper shows a symmetric image encryption based on bit-wise operation (XORing and Shifting. The basic idea is block ciphering (size of each block is 4 bytes technique to cipher the secret bytes, after that ciphered bytes are again shuffled among N positions (N is the size of secret file. The scheme is combination of substitution as well as transposition techniques which provides additional protection of the secret data. The substitution and transposition are done using dynamic substitution box (SBOX and transposition box (TBOX which are generated using the secret key and made to vary for each block during ciphering. The size of encrypted data is same as the size of secret data and the proposed scheme has been tested using different images. We have also presented the security analysis such as key sensitivity analysis, statistical analysis, and differential analysis to prove the strength of our algorithm against crypto analysis.

  15. Vector Quantization Techniques For Partial Encryption of Wavelet-based Compressed Digital Images

    H. A. Younis

    2009-01-01

    Full Text Available The use of image communication has increased in recent years. In this paper, newpartial encryption schemes are used to encrypt only part of the compressed data. Only6.25-25% of the original data is encrypted for four different images, resulting in asignificant reduction in encryption and decryption time. In the compression step, anadvanced clustering analysis technique (Fuzzy C-means (FCM is used. In the encryptionstep, the permutation cipher is used. The effect of number of different clusters is studied.The proposed partial encryption schemes are fast and secure, and do not reduce thecompression performance of the underlying selected compression methods as shown inexperimental results and conclusion.

  16. Classification of Novel Selected Region of Interest for Color Image Encryption

    Lahieb Mohammed Jawad; Ghazali Sulong

    2015-01-01

    Securing digital image in exchanging huge multimedia data over internet with limited bandwidth is a significant and sensitive issue. Selective image encryption being an effective method for reducing the amount of encrypted data can achieve adequate security enhancement. Determining and selecting the region of interest in digital color images is challenging for selective image encryption due to their complex structure and distinct regions of varying importance. We propose a new feature in acqu...

  17. Hardware realization of chaos based block cipher for image encryption

    Barakat, Mohamed L.

    2011-12-01

    Unlike stream ciphers, block ciphers are very essential for parallel processing applications. In this paper, the first hardware realization of chaotic-based block cipher is proposed for image encryption applications. The proposed system is tested for known cryptanalysis attacks and for different block sizes. When implemented on Virtex-IV, system performance showed high throughput and utilized small area. Passing successfully in all tests, our system proved to be secure with all block sizes. © 2011 IEEE.

  18. A Color image encryption scheme based on Generalized Synchronization Theorem

    Han shuangshuang

    2013-01-01

    Base on a generalized synchronization theorem (GCS) for discrete chaotic system, this paper introduces a new 6-dimensional generalized chaos synchronization system based on 3D-Lorenz map. Numerical simulation showed that two pair variables of the synchronization system achieve generalized synchronization via a transform H.Combining with the 2-Dimension non equilateral Arnold transformation, a color image encryption scheme was designed. Analyzing the key sensitivity, key space, histogram, info...

  19. Reversible Integer Wavelet Transform for the Joint of Image Encryption and Watermarking

    Bin Wang

    2015-01-01

    Full Text Available In recent years, signal processing in the encrypted domain has attracted considerable research interest, especially embedding watermarking in encrypted image. In this work, a novel joint of image encryption and watermarking based on reversible integer wavelet transform is proposed. Firstly, the plain-image is encrypted by chaotic maps and reversible integer wavelet transform. Then the lossless watermarking is embedded in the encrypted image by reversible integer wavelet transform and histogram modification. Finally an encrypted image containing watermarking is obtained by the inverse integer wavelet transform. What is more, the original image and watermarking can be completely recovered by inverse process. Numerical experimental results and comparing with previous works show that the proposed scheme possesses higher security and embedding capacity than previous works. It is suitable for protecting the image information.

  20. Composite encryption algorithm based on combing chaos control with choosing rule%基于混沌控制的选择复合加密算法

    王阳; 吴成茂; 梁睿

    2012-01-01

    为了提高图像信息的安全性,提出一种混沌技术和像素扩散加密相结合的图像加密新算法。利用Runge-Kutta方法求解四维混沌系统并经非线性处理产生混沌序列,用以控制图像扩散加密方式并获得多种扩散加密方法相融合的复合加密算法。对图像加密结果的相邻像素相关性、密钥敏感性、抗差分攻击等性能所进行的分析研究以及相关实验结果均表明,所提新算法具有可行性,且安全性能较高。%In order to enhance the security of image information, a New Image Encryption Algorithm based on combination of chaos control with pixel diffusion encryption is proposed. Firstly, Runge-Kutta method is used to solve fourth-dimension chaotic systems, and obtains a chaotic integer sequence by means of non-linear processing. Secondly, image diffusion encryption is controlled by combining the chaotic integer sequence with choosing rule, and obtained the composite encryption algorithm which includes a variety of diffusion encryption methods. In the end, anayze the correlations between pixels, the sensitivity of keys, against differential cryptanalysis of the image encryption results. Experimental results show that, the image encryption algorithm proposed in the paper is feasible and has high safety performance.

  1. Design a New Image Encryption using Fuzzy Integral Permutation with Coupled Chaotic Maps

    Yasaman Hashemi

    2013-01-01

    Full Text Available This article introduces a novel image encryption algorithm based on DNA addition combining and coupled two-dimensional piecewise nonlinear chaotic map. This algorithm consists of two parts. In the first part of the algorithm, a DNA sequence matrix is obtained by encoding each color component, and is divided into some equal blocks and then the generated sequence of Sugeno integral fuzzy and the DNA sequence addition operation is used to add these blocks. Next, the DNA sequence matrix from the previous step is decoded and the complement operation to the result of the added matrix is performed by using Sugeno fuzzy integral. In the second part of the algorithm, the three modified color components are encrypted in a coupling fashion in such a way to strengthen the cryptosystem security. It is observed that the histogram, the correlation and avalanche criterion, can satisfy security and performance requirements (Avalanche criterion > 0.49916283. The experimental results obtained for the CVG-UGR image databases reveal the fact that the proposed algorithm is suitable for practical use to protect the security of digital image information over the Internet.

  2. Security enhancement of double-random phase encryption by iterative algorithm

    We propose an approach to enhance the security of optical encryption based on double-random phase encryption in a 4f system. The phase key in the input plane of the 4f system is generated by the Yang–Gu algorithm to control the phase of the encrypted information in the output plane of the 4f system, until the phase in the output plane converges to a predesigned distribution. Only the amplitude of the encrypted information must be recorded as a ciphertext. The information, which needs to be transmitted, is greatly reduced. We can decrypt the ciphertext with the aid of the predesigned phase distribution and the phase key in the Fourier plane. Our approach can resist various attacks. (paper)

  3. Hiding a Covert Digital Image by Assembling the RSA Encryption Method and the Binary Encoding Method

    Kuang Tsan Lin; Sheng Lih Yeh

    2014-01-01

    The Rivest-Shamir-Adleman (RSA) encryption method and the binary encoding method are assembled to form a hybrid hiding method to hide a covert digital image into a dot-matrix holographic image. First, the RSA encryption method is used to transform the covert image to form a RSA encryption data string. Then, all the elements of the RSA encryption data string are transferred into binary data. Finally, the binary data are encoded into the dot-matrix holographic image. The pixels of the dot-matri...

  4. Performance Analysis of Most Common Encryption Algorithms on Different Web Browsers

    R. Umarani

    2012-11-01

    Full Text Available The hacking is the greatest problem in the wireless local area network (WLAN. Many algorithms like DES, 3DES, AES,UMARAM, RC6 and UR5 have been used to prevent the outside attacks to eavesdrop or prevent the data to be transferred to the end-user correctly. We have proposed a Web programming language to be analyzed with five Web browsers in term of their performances to process the encryption of the programming language’s script with the Web browsers. This is followed by conducting tests simulation in order to obtain the best encryption algorithm versus Web browser. The results of the experimental analysis are presented in the form of graphs. We finally conclude on the findings that different algorithms perform differently to different Web browsers like Internet Explorer, Mozilla Firefox, Opera and Netscape Navigator. Hence, we now determine which algorithm works best and most compatible with which Web browser.A comparison has been conducted for those encryption algorithms at different settings for each algorithm such as encryption/decryption speed in the different web Browsers. Experimental results are given to demonstrate the effectiveness of each algorithm.

  5. CRYPTANALYSIS OF AN IMAGE ENCRYPTION SCHEME WITH A PSEUDORANDOM PERMUTATION AND ITS IMPROVED VERSION

    Wang Jing; Jiang Guoping; Lin Bing

    2012-01-01

    Under Kerckhoff principle,this paper discusses the security property of an image encryption scheme with a pseudorandom permutation.Some findings on the security problems of the algorithm are reported in the following:(1) If each row or column of the plain-image matrix is the same,the receiver cannot decrypt correctly.(2) Each plain-text word is correlated with single cipher-text word,but independent of other cipher-text word,which cannot meet the principles of algorithm designdiffusion and confusion.(3) If the cycle numbers β are relatively small,statistics attack can be used to reveal some visual information of any other plain-images encrypted with the same secret key.Considering the above problems,we propose an improved algorithm and then analyze its performance.Theoretical analysis and simulation results show that the improved algorithm can obtain better cryptographic properties,such as statistical characteristics,difference characteristics,and so on.

  6. Chaos-based encryption for fractal image coding

    Yuen Ching-Hung; Wong Kwok-Wo

    2012-01-01

    A chaos-based cryptosystem for fractal image coding is proposed.The Rényi chaotic map is employed to determine the order of processing the range blocks and to generate the keystream for masking the encoded sequence.Compared with the standard approach of fractal image coding followed by the Advanced Encryption Standard,our scheme offers a higher sensitivity to both plaintext and ciphertext at a comparable operating efficiency.The keystream generated by the Rényi chaotic map passes the randomness tests set by the United States National Institute of Standards and Technology,and so the proposed scheme is sensitive to the key.

  7. An image encryption approach based on chaotic maps

    It is well-known that images are different from texts in many aspects, such as highly redundancy and correlation, the local structure and the characteristics of amplitude-frequency. As a result, the methods of conventional encryption cannot be applicable to images. In this paper, we improve the properties of confusion and diffusion in terms of discrete exponential chaotic maps, and design a key scheme for the resistance to statistic attack, differential attack and grey code attack. Experimental and theoretical results also show that our scheme is efficient and very secure

  8. Design and Analysis of a Novel Digital Image Encryption Scheme

    Pareek, Narendra K

    2012-01-01

    In this paper, a new image encryption scheme using a secret key of 144-bits is proposed. In the substitution process of the scheme, image is divided into blocks and subsequently into color components. Each color component is modified by performing bitwise operation which depends on secret key as well as a few most significant bits of its previous and next color component. Three rounds are taken to complete substitution process. To make cipher more robust, a feedback mechanism is also applied by modifying used secret key after encrypting each block. Further, resultant image is partitioned into several key based dynamic sub-images. Each sub-image passes through the scrambling process where pixels of sub-image are reshuffled within itself by using a generated magic square matrix. Five rounds are taken for scrambling process. The propose scheme is simple, fast and sensitive to the secret key. Due to high order of substitution and permutation, common attacks like linear and differential cryptanalysis are infeasibl...

  9. Study of Encryption and Decryption of Wave File in Image Formats

    Rahul R Upadhyay

    2013-01-01

    This paper describes a novel method of encrypting wave files in popular image formats like JPEG, TIF and PNG along with retrieving them from these image files. MATLAB software is used to perform matrix manipulation to encrypt and decrypt sound files into and from image files. This method is not only a stenographic means but also a data compression technique.

  10. Study of Encryption and Decryption of Wave File in Image Formats

    Rahul R Upadhyay

    2013-07-01

    Full Text Available This paper describes a novel method of encrypting wave files in popular image formats like JPEG, TIF and PNG along with retrieving them from these image files. MATLAB software is used to perform matrix manipulation to encrypt and decrypt sound files into and from image files. This method is not only a stenographic means but also a data compression technique.

  11. Partial Encryption of Co mpressed Image Using Threshold Quantization and AES Cipher

    H.A.Younis

    2012-01-01

    Full Text Available Cryptography is one of the technological means to provide security to data beingtransmitted on information and communication systems.When it is necessary to securelytransmit data in limited bandwidth, both compression and encryption must be performed.Researchers have combined compression and encryption together to reduce the overallprocessing time.In this paper, new partial encryption schemes are proposed to encrypt only part of thecompressed image.Soft and hard threshold compression methods are used in thecompressionstep and the Advanced Encryption Standard (AES cipher is used forthe encryption step. The effect of different threshold values on the performance of the proposed schemes are studied. The proposed partial encryption schemes are fast, secure, and do not reduce the compression performance of the underlying selected compression methods.

  12. Optical encryption for large-sized images using random phase-free method

    Shimobaba, Tomoyoshi; Endo, Yutaka; Hirayama, Ryuji; Hiyama, Daisuke; Hasegawa, Satoki; Nagahama, Yuki; Sano, Marie; Sugie, Takashige; Ito, Tomoyoshi

    2015-01-01

    We propose an optical encryption framework that can encrypt and decrypt large-sized images beyond the size of the encrypted image using our two methods: random phase-free method and scaled diffraction. In order to record the entire image information on the encrypted image, the large-sized images require the random phase to widely diffuse the object light over the encrypted image; however, the random phase gives rise to the speckle noise on the decrypted images, and it may be difficult to recognize the decrypted images. In order to reduce the speckle noise, we apply our random phase-free method to the framework. In addition, we employ scaled diffraction that calculates light propagation between planes with different sizes by changing the sampling rates.

  13. A novel chaotic image encryption scheme using DNA sequence operations

    Wang, Xing-Yuan; Zhang, Ying-Qian; Bao, Xue-Mei

    2015-10-01

    In this paper, we propose a novel image encryption scheme based on DNA (Deoxyribonucleic acid) sequence operations and chaotic system. Firstly, we perform bitwise exclusive OR operation on the pixels of the plain image using the pseudorandom sequences produced by the spatiotemporal chaos system, i.e., CML (coupled map lattice). Secondly, a DNA matrix is obtained by encoding the confused image using a kind of DNA encoding rule. Then we generate the new initial conditions of the CML according to this DNA matrix and the previous initial conditions, which can make the encryption result closely depend on every pixel of the plain image. Thirdly, the rows and columns of the DNA matrix are permuted. Then, the permuted DNA matrix is confused once again. At last, after decoding the confused DNA matrix using a kind of DNA decoding rule, we obtain the ciphered image. Experimental results and theoretical analysis show that the scheme is able to resist various attacks, so it has extraordinarily high security.

  14. An Improved FPGA Implementation of the Modified Hybrid Hiding Encryption Algorithm (MHHEA) for Data Communication Security

    Farouk, Hala A

    2011-01-01

    The hybrid hiding encryption algorithm, as its name implies, embraces concepts from both steganography and cryptography. In this exertion, an improved micro-architecture Field Programmable Gate Array (FPGA) implementation of this algorithm is presented. This design overcomes the observed limitations of a previously-designed micro-architecture. These observed limitations are: no exploitation of the possibility of parallel bit replacement, and the fact that the input plaintext was encrypted serially, which caused a dependency between the throughput and the nature of the used secret key. This dependency can be viewed by some as vulnerability in the security of the implemented micro-architecture. The proposed modified micro-architecture is constructed using five basic modules. These modules are; the message cache, the message alignment module, the key cache, the comparator, and at last the encryption module. In this work, we provide comprehensive simulation and implementation results. These are: the timing diagra...

  15. Data Encryption and Decryption Algorithm Using Hamming Code and Arithmetic Operations

    Kurapati Sundar Teja; Shanmukha Mallikarjuna Bandaru

    2015-01-01

    This paper explains the implementation of data encryption and decryption algorithm using hamming code and arithmetic operations with the help of Verilog HDL. As the days are passing the old algorithms are not remained so strong cryptanalyst are familiar with them. Hamming code is one of forward error correcting code which has got many applications. In this paper hamming code algorithm was discussed and the implementation of it was done with arithmetic operations. For high security...

  16. Encryption On Grayscale Image For Digital Image Confidentiality Using Shamir Secret Sharing Scheme

    Rodiah; Anggraini, Dyah; Fitrianingsih; Kazhimi, Farizan

    2016-04-01

    The use of high-frequency internet in the process of exchanging information and digital transaction is often accompanied by transmitting digital image in the form of raster images. Secret sharing schemes are multiparty protocols that related to the key establishment which provides protection against any threats of losing cryptography key. The greater the key duplication, the higher the risk of losing the key and vice versa. In this study, Secret Sharing Method was used by employing Shamir Threshold Scheme Algorithm on grayscale digital image with the size of 256×256 pixel obtaining 128×128 pixels of shared image with threshold values (4, 8). The result number of shared images were 8 parts and the recovery process can be carried out by at least using 4 shares of the 8 parts. The result of encryption on grayscale image is capable of producing vague shared image (i.e., no perceptible information), therefore a message in the form of digital image can be kept confidential and secure.

  17. Multifractional Fourier Transform Method and Its Applications to Image Encryption

    RANQiwen; WANGQi; MAJing; TANLiying

    2003-01-01

    The multiplicity of the fractional Fourier transform(FRFT),which is intrinsic in any fractional operator,has been claimed by several authors,but never across-the-board developed.Particularly,the weight-type FRFT(WFRFT) has not been investigated.Starting with defining the multifractional Fourier transform (MFRFT),we gained the generalization permutation matrix group (GPMG)representation and multiplicity of the MFRFT,and the relationships among the MFRFT the standard WFRFT and the standard CFRFT.Finally,as a application,a novel image encryption method hased on the MFRFT is propounded.Similation results show that this method is safe,practicable and impactful.

  18. 加密算法之RSA算法%Encryption Algorithm of the RSA Algorithm

    盛仲飙

    2012-01-01

    RSA algorithm is one of the most widely used non-symmetric cipher system. On the base of the study of RSA algorithm theory,principle, algorithm description and so on,the paper further studies the details of the problems in the implementation of RSA algorithm that should be paid attention and its application in the encryption/ decryption, digital signatures, key exchange. Finally, the paper proposes a kind of private key power module operation improvement scheme. The scheme improved the speed of RSA algorithm in the decryption.%RSA算法是使用最广泛的一种非对称密码体制.在对RSA算法的理论基础、原理、算法描述等进行研究的基础上,近一步研究了RSA算法在实现时应注意的问题以及它在数字签名、密钥交换等方面的应用.最后提出了一种对私有密钥进行幂模运算的改进方案,提高了RSA算法在解密时的运算速度.

  19. An Investigation into Encrypted Message Hiding Through Images Using LSB

    FAHIM IRFAN ALAM

    2011-02-01

    Full Text Available Data security has become a cause of concern because of the electronic spying especially in the military, government and many sectors of communication fields. This paper investigates a representation forembedding secure data within an image based on substitution method which gives the scope of large amount of secret message hiding within digital images. Specifically we used least significant bit (LSBsubstitution method to encrypt the message in image file. For improving the performance of LSB which is very simple by nature, we performed noise filtering at the beginning of the process to ensure noise-free data to be transmitted through the image. Also, after the extraction of the secure message at the receiver portion of the network, we used Automatic Repeat reQuest (ARQ method as the error detection and correction process to ensure that the correct data has been transmitted and no information is lost. The improved framework resulted in satisfactory outcomes.

  20. Sparse-based multispectral image encryption via ptychography

    Rawat, Nitin; Shi, Yishi; Kim, Byoungho; Lee, Byung-Geun

    2015-12-01

    Recently, we proposed a model of securing a ptychography-based monochromatic image encryption system via the classical Photon-counting imaging (PCI) technique. In this study, we examine a single-channel multispectral sparse-based photon-counting ptychography imaging (SMPI)-based cryptosystem. A ptychography-based cryptosystem creates a complex object wave field, which can be reconstructed by a series of diffraction intensity patterns through an aperture movement. The PCI sensor records only a few complex Bayer patterned samples that have been utilized in the decryption process. Sparse sensing and nonlinear properties of the classical PCI system, together with the scanning probes, enlarge the key space, and such a combination therefore enhances the system's security. We demonstrate that the sparse samples have adequate information for image decryption, as well as information authentication by means of optical correlation.

  1. Bluetooth Based Chaos Synchronization Using Particle Swarm Optimization and Its Applications to Image Encryption

    Yau, Her-Terng; Hung, Tzu-Hsiang; Hsieh, Chia-Chun

    2012-01-01

    This study used the complex dynamic characteristics of chaotic systems and Bluetooth to explore the topic of wireless chaotic communication secrecy and develop a communication security system. The PID controller for chaos synchronization control was applied, and the optimum parameters of this PID controller were obtained using a Particle Swarm Optimization (PSO) algorithm. Bluetooth was used to realize wireless transmissions, and a chaotic wireless communication security system was developed in the design concept of a chaotic communication security system. The experimental results show that this scheme can be used successfully in image encryption. PMID:22969355

  2. Bluetooth Based Chaos Synchronization Using Particle Swarm Optimization and Its Applications to Image Encryption

    Tzu-Hsiang Hung

    2012-06-01

    Full Text Available This study used the complex dynamic characteristics of chaotic systems and Bluetooth to explore the topic of wireless chaotic communication secrecy and develop a communication security system. The PID controller for chaos synchronization control was applied, and the optimum parameters of this PID controller were obtained using a Particle Swarm Optimization (PSO algorithm. Bluetooth was used to realize wireless transmissions, and a chaotic wireless communication security system was developed in the design concept of a chaotic communication security system. The experimental results show that this scheme can be used successfully in image encryption.

  3. Vulnerability issues on research in WLAN encryption algorithms WEP WPA/WPA2 Personal

    This paper presents historic and new evidence that wireless encryption algorithms can be cracked or even bypassed which has been proved by other researchers. The paper presents a description of how WEP and WPA/WPA2 Personal encrypt data and how the passphrase is shared between the nodes of the network. Modern tools available on the internet have been evaluated, decomposed and tested to provide evidence on the reliability of passwords. A number of criteria are used to compare the tools and their efficiency

  4. Hiding a Covert Digital Image by Assembling the RSA Encryption Method and the Binary Encoding Method

    Kuang Tsan Lin

    2014-01-01

    Full Text Available The Rivest-Shamir-Adleman (RSA encryption method and the binary encoding method are assembled to form a hybrid hiding method to hide a covert digital image into a dot-matrix holographic image. First, the RSA encryption method is used to transform the covert image to form a RSA encryption data string. Then, all the elements of the RSA encryption data string are transferred into binary data. Finally, the binary data are encoded into the dot-matrix holographic image. The pixels of the dot-matrix holographic image contain seven groups of codes used for reconstructing the covert image. The seven groups of codes are identification codes, covert-image dimension codes, covert-image graylevel codes, pre-RSA bit number codes, RSA key codes, post-RSA bit number codes, and information codes. The reconstructed covert image derived from the dot-matrix holographic image and the original covert image are exactly the same.

  5. Applying Encryption Algorithm for Data Security and Privacy in Cloud Computing

    Mohit Marwaha

    2013-01-01

    Full Text Available Cloud computing is the next big thing after internet in the field of information technology; some say its a metaphor for internet. It is an Internet-based computing technology, in which software, shared recourses and information, are provided to consumers and devices on-demand, and as per users requirement on a pay per use model. Even though the cloud continues to grow in popularity, Usability and respectability, Problems with data protection and data privacy and other Security issues play a major setback in the field of Cloud Computing. Privacy and security are the key issue for cloud storage. Encryption is a well known technology for protecting sensitive data. Use of the combination of Public and Private key encryption to hide the sensitive data of users, and cipher text retrieval. The paper analyzes the feasibility of the applying encryption algorithm for data security and privacy in cloud Storage.

  6. Image File Security using Base-64 Algorithm

    Pooja Guwalani

    2014-12-01

    Full Text Available Information security is becoming a vital component of any data storage and transmission operations. Since visual representation of data is gaining importance, data in the form of images are used to exchange and convey information between entities. As the use of digital techniques for transmitting and storing images are increasing, it becomes an important issue to protect the confidentiality, integrity and authenticity of images. There are various techniques which are discovered to encrypt the images to make them more secure. The primary goal of this paper is security management. A mechanism to provide authentication of users and ensure integrity, accuracy and safety of images. Moreover, an image-based data requires more effort during encryption and decryption. In this paper, we describe how Base64 algorithm can be used to achieve this purpose.

  7. Encrypted imaging based on algebraic implementation of double random phase encoding.

    Nakano, Kazuya; Takeda, Masafumi; Suzuki, Hiroyuki; Yamaguchi, Masahiro

    2014-05-10

    The security of important information captured by sensors and cameras is currently a growing concern as information theft via techniques such as side-channel attacks become increasingly more prevalent. Double random phase encoding (DRPE) is an optical encryption method based on optical Fourier transform that is currently being used to implement secure coherent optical systems. In this paper, we propose a new DRPE implementation for incoherent optical systems based on integral photography that can be applied to "encrypted imaging (EI)" to optically encrypt an image before it is captured by an image sensor. Because the proposed incoherent DRPE is constituted from conventional DRPE by rewriting the optical encryption via discretization and Euler's formula, its security level is the same as that of conventional DRPE. The results of an experiment in which we encrypted a plaintext image optically and then decrypted it numerically demonstrate that our proposed incoherent optical security system is feasible. PMID:24922013

  8. Novel Quantum Encryption Algorithm Based on Multiqubit Quantum Shift Register and Hill Cipher

    Based on a quantum shift register, a novel quantum block cryptographic algorithm that can be used to encrypt classical messages is proposed. The message is encoded and decoded by using a code generated by the quantum shift register. The security of this algorithm is analysed in detail. It is shown that, in the quantum block cryptographic algorithm, two keys can be used. One of them is the classical key that is used in the Hill cipher algorithm where Alice and Bob use the authenticated Diffie Hellman key exchange algorithm using the concept of digital signature for the authentication of the two communicating parties and so eliminate the man-in-the-middle attack. The other key is generated by the quantum shift register and used for the coding of the encryption message, where Alice and Bob share the key by using the BB84 protocol. The novel algorithm can prevent a quantum attack strategy as well as a classical attack strategy. The problem of key management is discussed and circuits for the encryption and the decryption are suggested

  9. Data Encryption and Decryption Algorithm Using Hamming Code and Arithmetic Operations

    Kurapati Sundar Teja

    2015-08-01

    Full Text Available This paper explains the implementation of data encryption and decryption algorithm using hamming code and arithmetic operations with the help of Verilog HDL. As the days are passing the old algorithms are not remained so strong cryptanalyst are familiar with them. Hamming code is one of forward error correcting code which has got many applications. In this paper hamming code algorithm was discussed and the implementation of it was done with arithmetic operations. For high security some arithmetic operations are added with hamming code process. A 3-bit data will be encrypted as 14-bit and using decryption process again we will receives 3-bit original data. The implemented design was tested on Spartan3A FPGA kit.

  10. Double-image encryption scheme combining DWT-based compressive sensing with discrete fractional random transform

    Zhou, Nanrun; Yang, Jianping; Tan, Changfa; Pan, Shumin; Zhou, Zhihong

    2015-11-01

    A new discrete fractional random transform based on two circular matrices is designed and a novel double-image encryption-compression scheme is proposed by combining compressive sensing with discrete fractional random transform. The two random circular matrices and the measurement matrix utilized in compressive sensing are constructed by using a two-dimensional sine Logistic modulation map. Two original images can be compressed, encrypted with compressive sensing and connected into one image. The resulting image is re-encrypted by Arnold transform and the discrete fractional random transform. Simulation results and security analysis demonstrate the validity and security of the scheme.

  11. A New Loss-Tolerant Image Encryption Scheme Based on Secret Sharing and Two Chaotic Systems

    Li Li; Ahmed A. Abd El-Latif; Zhenfeng Shi and Xiamu Niu

    2012-01-01

    In this study, we propose an efficient loss-tolerant image encryption scheme that protects both confidentiality and loss-tolerance simultaneously in shadow images. In this scheme, we generate the key sequence based on two chaotic maps and then encrypt the image during the sharing phase based on Shamir’s method. Experimental results show a better performance of the proposed scheme for different images than other methods from human vision. Security analysis confirms a high probability to resist...

  12. EFFICIENT ALGORITHM FOR RSA TEXT ENCRYPTION USING CUDA-C

    Sonam Mahajan

    2014-05-01

    Full Text Available Modern-day computer security relies heavily on cryptography as a means to protect the data that we have become increasingly reliant on. The main research in computer security domain is how to enhance the speed of RSA algorithm. The computing capability of Graphic Processing Unit as a co-processor of the CPU can leverage massive-parallelism. This paper presents a novel algorithm for calculating modulo value that can process large power of numbers which otherwise are not supported by built-in data types. First the traditional algorithm is studied. Secondly, the parallelized RSA algorithm is designed using CUDA framework. Thirdly, the designed algorithm is realized for small prime numbers and large prime number . As a result the main fundamental problem of RSA algorithm such as speed and use of poor or small prime numbers that has led to significant security holes, despite the RSA algorithm's mathematical soundness can be alleviated by this algorithm.

  13. Separable and Error-Free Reversible Data Hiding in Encrypted Image with High Payload

    Yin, Zhaoxia; Luo, Bin; Hong, Wien

    2014-01-01

    This paper proposes a separable reversible data-hiding scheme in encrypted image which offers high payload and error-free data extraction. The cover image is partitioned into nonoverlapping blocks and multigranularity encryption is applied to obtain the encrypted image. The data hider preprocesses the encrypted image and randomly selects two basic pixels in each block to estimate the block smoothness and indicate peak points. Additional data are embedded into blocks in the sorted order of block smoothness by using local histogram shifting under the guidance of the peak points. At the receiver side, image decryption and data extraction are separable and can be free to choose. Compared to previous approaches, the proposed method is simpler in calculation while offering better performance: larger payload, better embedding quality, and error-free data extraction, as well as image recovery. PMID:24977214

  14. Separable and Error-Free Reversible Data Hiding in Encrypted Image with High Payload

    Zhaoxia Yin

    2014-01-01

    Full Text Available This paper proposes a separable reversible data-hiding scheme in encrypted image which offers high payload and error-free data extraction. The cover image is partitioned into nonoverlapping blocks and multigranularity encryption is applied to obtain the encrypted image. The data hider preprocesses the encrypted image and randomly selects two basic pixels in each block to estimate the block smoothness and indicate peak points. Additional data are embedded into blocks in the sorted order of block smoothness by using local histogram shifting under the guidance of the peak points. At the receiver side, image decryption and data extraction are separable and can be free to choose. Compared to previous approaches, the proposed method is simpler in calculation while offering better performance: larger payload, better embedding quality, and error-free data extraction, as well as image recovery.

  15. Optical Image Encryption Using Devil’s Vortex Toroidal Lens in the Fresnel Transform Domain

    Hukum Singh; Yadav, A K; Sunanda Vashisth; Kehar Singh

    2015-01-01

    We have carried out a study of optical image encryption in the Fresnel transform (FrT) domain, using a random phase mask (RPM) in the input plane and a phase mask based on devil’s vortex toroidal lens (DVTL) in the frequency plane. The original images are recovered from their corresponding encrypted images by using the correct parameters of the FrT and the parameters of DVTL. The use of a DVTL-based structured mask enhances security by increasing the key space for encryption and also aids in ...

  16. Medical Image Encryption and Compression Scheme Using Compressive Sensing and Pixel Swapping Based Permutation Approach

    Li-bo Zhang; Zhi-liang Zhu; Ben-qiang Yang; Wen-yuan Liu; Hong-feng Zhu; Ming-yu Zou

    2015-01-01

    This paper presents a solution to satisfy the increasing requirements for secure medical image transmission and storage over public networks. The proposed scheme can simultaneously encrypt and compress the medical image using compressive sensing (CS) and pixel swapping based permutation approach. In the CS phase, the plain image is compressed and encrypted by chaos-based Bernoulli measurement matrix, which is generated under the control of the introduced Chebyshev map. The quantized measureme...

  17. Authentication and Encryption in GSM and 3GUMTS: An Emphasis on Protocols and Algorithms

    Elouafiq, Ali

    2012-01-01

    Mobile communication touches every aspect of our life, it become one of the major dependencies that the 21st Century civilizations rely on. Thereby, security is a major issue that should be targeted by communication technologies. In this paper we will target authentication and encryption in GSM and 3G/UMTS. In order to understand clearly how things work, we will start by presenting the architecture of each network, its major components, its authentication algorithms, protocols used, and KASUMI Block Cipher.

  18. Asymmetric multiple-image encryption based on the cascaded fractional Fourier transform

    Li, Yanbin; Zhang, Feng; Li, Yuanchao; Tao, Ran

    2015-09-01

    A multiple-image cryptosystem is proposed based on the cascaded fractional Fourier transform. During an encryption procedure, each of the original images is directly separated into two phase masks. A portion of the masks is subsequently modulated into an interim mask, which is encrypted into the ciphertext image; the others are used as the encryption keys. Using phase truncation in the fractional Fourier domain, one can use an asymmetric cryptosystem to produce a real-valued noise-like ciphertext, while a legal user can reconstruct all of the original images using a different group of phase masks. The encryption key is an indivisible part of the corresponding original image and is still useful during decryption. The proposed system has high resistance to various potential attacks, including the chosen-plaintext attack. Numerical simulations also demonstrate the security and feasibility of the proposed scheme.

  19. Ensemble Of Blowfish With Chaos Based S Box Design For Text And Image Encryption

    Jeyamala Chandrasekaran

    2011-08-01

    Full Text Available The rapid and extensive usage of Internet in the present decade has put forth information security as an utmost concern. Most of the commercial transactions taking place over the Internet involves a wide variety of data including text, images, audio and video. With the increasing use of digital techniques for transmitting and storing Multimedia data, the fundamental issue of protecting the confidentiality, integrity and authenticity of the information poses a major challenge for security professionals and hassled to the major developments in Cryptography . In cryptography, an S-Box (Substitution-box is a basic componentof symmetric key algorithms, which performs substitution and is typically used to make the relationship between the key and the cipher text non linear and most of the symmetric key algorithms like DES, Blowfish makes use of S boxes. This paper proposes a new method for design of S boxes based on chaos theory. Chaotic equations are popularly known for its randomness, extreme sensitivity to initial conditions and ergodicity. The modified design has been tested with blowfish algorithm which has no effective crypt analysis reported against its design till date because of its salient design features including the key dependant s boxes and complex key generation process. However every new key requires pre-processing equivalent to encrypting about 4 kilobytes of text, which is very slow compared to other block ciphers and it prevents its usage in memory limited applications and embedded systems. The modified design of S boxesmaintains the non linearity [3] [5] and key dependency factors of S boxes with a major reduction in time complexity of generation of S boxes and P arrays. The algorithm has been implemented and the proposed design has been analyzed for size of key space, key sensitivity and Avalanche effect. Experimental results on text and Image Encryption show that the modified design of key generation continues to offer the same

  20. On encryption-compression tradeoff of pre/post-filtered images

    Gurijala, Aparna; Khayam, Syed A.; Radha, Hayder; Deller, J. R., Jr.

    2005-09-01

    Advances in network communications have necessitated secure local-storage and transmission of multimedia content. In particular, military networks need to securely store sensitive imagery which at a later stage may be transmitted over bandwidth-constrained wireless networks. This work investigates compression efficiency of JPEG and JPEG 2000 standards for encrypted images. An encryption technique proposed by Kuo et al. in [4] is employed. The technique scrambles the phase spectrum of an image by addition of the phase of an all-pass pre-filter. The post-filter inverts the encryption process, provided the correct pseudo-random filter coefficients are available at the receiver. Additional benefits of pre/post-filter encryption include the prevention of blocking effects and better robustness to channel noise [4]. Since both JPEG and JPEG 2000 exploit spatial and perceptual redundancies for compression, pre/post-filtered (encrypted) images are susceptible to compression inefficiencies. The PSNR difference between the unencrypted and pre/post-filtered images after decompression is determined for various compression rates. Compression efficiency decreases with an increase in compression rate. For JPEG and JPEG 2000 compression rates between 0.5 to 2.5 bpp, the difference in PSNR is negligible. Partial encryption is proposed wherein a subset of image phase coefficients are scrambled. Due to the phase sensitivity of images, even partial scrambling of the phase information results in unintelligible data. The effect of compression on partially encrypted images is observed for various bit-rates. When 25% of image phase coefficients are scrambled, the JPEG and JPEG 2000 compression performance of encrypted images is almost similar to that of unencrypted images for compression rates in the 0.5 to 3.5 bpp range.

  1. A Modified Location-Dependent Image Encryption for Mobile Information System

    Prasad Reddy.P.V.G.D

    2010-05-01

    Full Text Available The wide spread use of WLAN (Wireless LAN and the popularity of mobile devices increases the frequency of data transmission among mobile users. In such scenario, a need for Secure Communication arises. Secure communication is possible through encryption of data. A lot of encryption techniques have evolved over time. However, most of the data encryption techniques are location-independent. Data encrypted with such techniques can be decrypted anywhere. The encryption technology cannot restrict the location of data decryption. GPS-based encryption (or geoencryption is an innovative technique that uses GPS-technology to encode location information into the encryption keys to provide location based security. In this paper a location-dependent approach is proposed for mobile information system. The mobile client transmits a target latitude/longitude coordinate and an LDEA key is obtained for data encryption to information server. The client can only decrypt the ciphertext when the coordinate acquired form GPS receiver matches with the target coordinate. For improved security, a random key (R-key is incorporated in addition to the LDEA key. The proposed method is applied for images.

  2. Advanced Steganography Algorithm Using Randomized Intermediate QR Host Embedded With Any Encrypted Secret Message: ASA_QR Algorithm

    Somdip Dey; Kalyan Mondal; Joyshree Nath; Asoke Nath

    2012-01-01

    Due to tremendous growth in communication technology, now it is a real problem / challenge to send some confidential data / information through communication network. For this reason, Nath et al. developed several information security systems, combining cryptography and steganography together, and the present method, ASA_QR, is also one of them. In the present paper, the authors present a new steganography algorithm to hide any small encrypted secret message inside QR CodeTM , which is then ...

  3. A Parallel Encryption Algorithm for Block Ciphers Based on Reversible Programmable Cellular Automata

    Das, Debasis

    2010-01-01

    A Cellular Automata (CA) is a computing model of complex System using simple rule. In CA the problem space into number of cell and each cell can be one or several final state. Cells are affected by neighbours' to the simple rule. Cellular Automata are highly parallel and discrete dynamical systems, whose behaviour is completely specified in terms of a local relation. This paper deals with the Cellular Automata (CA) in cryptography for a class of Block Ciphers through a new block encryption algorithm based on Reversible Programmable Cellular Automata Theory. The proposed algorithm belongs to the class of symmetric key systems.

  4. A Compression & Encryption Algorithm on DNA Sequences Using Dynamic Look up Table and Modified Huffman Techniques

    Syed Mahamud Hossein

    2013-09-01

    Full Text Available Storing, transmitting and security of DNA sequences are well known research challenge. The problem has got magnified with increasing discovery and availability of DNA sequences. We have represent DNA sequence compression algorithm based on Dynamic Look Up Table (DLUT and modified Huffman technique. DLUT consists of 43(64 bases that are 64 sub-stings, each sub-string is of 3 bases long. Each sub-string are individually coded by single ASCII code from 33(! to 96(` and vice versa. Encode depends on encryption key choose by user from four base pair {a,t.g and c}and decode also require decryption key provide by the encoded user. Decoding must require authenticate input for encode the data. The sub-strings are combined into a Dynamic Look up Table based pre-coding routine. This algorithm is tested on reverse; complement & reverse complement the DNA sequences and also test on artificial DNA sequences of equivalent length. Speed of encryption and security levels are two important measurements for evaluating any encryption system. Due to proliferate of ubiquitous computing system, where digital contents are accessible through resource constraint biological database security concern is very important issue. A lot of research has been made to find an encryption system which can be run effectively in those biological databases. Information security is the most challenging question to protect the data from unauthorized user. The proposed method may protect the data from hackers. It can provide the three tier security, in tier one is ASCII code, in tier two is nucleotide (a,t,g and c choice by user and tier three is change of label or change of node position in Huffman Tree. Compression of the genome sequences will help to increase the efficiency of their use. The greatest advantage of this algorithm is fast execution, small memory occupation and easy implementation. Since the program to implement the technique have been written originally in the C language

  5. Improvement of Networked Control Systems Performance Using a New Encryption Algorithm

    Seyed Ali Mesbahifard

    2014-07-01

    Full Text Available Networked control systems are control systems which controllers and plants are connected via telecommunication network. One of the most important challenges in networked control systems is the problem of network time delay. Increasing of time delay may affect on control system performance extremely. Other important issue in networked control systems is the security problems. Since it is possible that unknown people access to network especially Internet, the probability of terrible attacks such as deception attacks is greater, therefore presentation of methods which could decrease time delay and increase system immunity are desired. In this paper a symmetric encryption with low data volume against deception attacks is proposed. This method has high security and low time delay rather than the other encryption algorithms and could improve the control system performance against deception attacks.

  6. A new method for decoding an encrypted text by genetic algorithms and its comparison with tabu search and simulated annealing

    Mahdi Sadeghzadeh

    2014-02-01

    Full Text Available Genetic Algorithm is an algorithm based on population and many optimization problems are solved with this method, successfully. With increasing demand for computer attacks, security, efficient and reliable Internet has increased. Cryptographic systems have studied the science of communication is hidden, and includes two case categories including encryption, password and analysis. In this paper, several code analyses based on genetic algorithms, tabu search and simulated annealing for a permutation of encrypted text are investigated. The study also attempts to provide and to compare the performance in terms of the amount of check and control algorithms and the results are compared.

  7. AN APPROACH TO DESIGN ADVANCED STANDARD ENCRYPTION ALGORITHM USING HARDWARE / SOFTWARE CO-DESIGN METHODOLOGY

    MEGHANA A. HASAMNIS

    2012-05-01

    Full Text Available An Advanced Standard Encryption Algorithm (AES is widely used in modern consumer electronicproducts for security. The IEEE 802.15.4 Low-Rate wireless sensor networks also use AES algorithm wherelow power consumption is the priority. To reduce the time taken for encryption of huge data, the algorithm hasto be implemented in hardware. To meet the requirement for low area the algorithm has to be implemented insoftware. Hence, a balance has to be achieved between hardware and software implementations in terms of areaand speed, so as to improve the overall performance of the system. Also with the co-design methodology totalthermal power dissipation is reduced. In this paper, 128 bit AES algorithm is implemented with hardware incombination with software using Altera NIOS II Processor platform. Altera’s Quartus II environment is used fordesign of the system. Cyclone II FPGA is used as a development platform. Software program is written in C language. NIOS II ntegrated Development Environment (IDE is used to integrate hardware and software together. By adopting hardware / software co-design methodology for implementation of AES, results show that a onsiderable improvement in speed can be achieved as compared to software only approach. Further, the significant reduction in area is achieved as compared to hardware only approach. By the approach of co-design an optimized design in terms of speed and area is achieved and also the thermal power dissipation is reduced

  8. A Stream Encryption Scheme with Both Key and Plaintext Avalanche Effects for Designing Chaos-Based Pseudorandom Number Generator with Application to Image Encryption

    Han, Dandan; Min, Lequan; Chen, Guanrong

    Based on a stream encryption scheme with avalanche effect (SESAE), a stream encryption scheme with both key avalanche effect and plaintext avalanche effect (SESKPAE) is introduced. Using this scheme and an ideal 2d-word (d-segment) pseudorandom number generator (PRNG), a plaintext can be encrypted such that each bit of the ciphertext block has a change with the probable probability of (2d ‑ 1)/2d when any word of the key is changed or any bit of the plaintext is changed. To that end, a novel four-dimensional discrete chaotic system (4DDCS) is proposed. Combining the 4DDCS with a generalized synchronization (GS) theorem, a novel eight-dimensional discrete GS chaotic system (8DDGSCS) is constructed. Using the 8DDGSCS, a 216-word chaotic pseudorandom number generator (CPRNG) is designed. The keyspace of the 216-word CPRNG is larger than 21195. Then, the FIPS 140-2 test suit/generalized FIPS 140-2 test suit is used to test the randomness of the 1000-key streams consisting of 20000 bits generated by the 216-word CPRNG, the RC4 algorithm PRNG and the ZUC algorithm PRNG, respectively. The test results show that for the three PRNGs, there are 100%/98.9%, 99.9%/98.8%, 100%/97.9% key streams passing the tests, respectively. Furthermore, the SP800-22 test suite is used to test the randomness of four 100-key streams consisting of 1000000 bits generated by four PRNGs, respectively. The numerical results show that the randomness performances of the 216-word CPRNG is promising, showing that there are no significant correlations between the key streams and the perturbed key streams generated via the 216-word CPRNG. Finally, using the 216-word CPRNG and the SESKPAE to encrypt two gray-scale images, test results demonstrate that the 216-word CPRNG is able to generate both key avalanche effect and plaintext avalanche effect, which are similar to those generated via an ideal CPRNG, and performs better than other comparable schemes.

  9. 移动通信的图像加密系统设计与实现%Design and Implementation on the Image Encryption of Mobile Communication System

    万玉晴

    2015-01-01

    This article presents an image encryption system for smart phones that can solve the problems such as the application requirements of image encryption of smart phones and the current desktop encryption systems are not quite suitable for mobile terminal platform. It propose a technical method with low allocation and fast image encryption for mobile application with the use of image encryption technology based on chaos algorithm. The experiment result shows that the parallel multithreading technical strategy adopted by the system can improve over three times encryption and decryption efficiency of large pixel images. So it can provide a realizable solution for the real-time image encryption of smart phones.%针对智能手机图像的加密应用需求与目前台式加密系统不能很好地适用于移动终端平台等问题,本文设计了一套适用于智能手机的图像加密系统,结合基于混沌算法的图像加密技术,提出了适用于移动端应用的低配置、快速实现图像加密的技术方法。实验结果表明,系统采用的并行多线程技术路线,可以提高大像素图像的加解密效率三倍以上,为智能手机的实时图像加密提供了一种可实现解决方案。

  10. All-optical video-image encryption with enforced security level using independent component analysis

    Alfalou, A.; Mansour, A.

    2007-10-01

    In the last two decades, wireless communications have been introduced in various applications. However, the transmitted data can be, at any moment, intercepted by non-authorized people. That could explain why data encryption and secure transmission have gained enormous popularity. In order to secure data transmission, we should pay attention to two aspects: transmission rate and encryption security level. In this paper, we address these two aspects by proposing a new video-image transmission scheme. This new system consists in using the advantage of optical high transmission rate and some powerful signal processing tools to secure the transmitted data. The main idea of our approach is to secure transmitted information at two levels: at the classical level by using an adaptation of standard optical techniques and at a second level (spatial diversity) by using independent transmitters. In the second level, a hacker would need to intercept not only one channel but all of them in order to retrieve information. At the receiver, we can easily apply ICA algorithms to decrypt the received signals and retrieve information.

  11. MINIMIZATION OF DELAY TIME IN DYNAMIC ENCRYPTION ALGORITHM FOR REAL-TIME APPLICATIONS (DEA-RTA)

    Kuti Toyin Sadiq; Madhavi Kumari

    2014-01-01

    Real-Time Applications (RTA) such as Voice-over IP (VoIP), Instant messages (IM), and video conferencing are sensitive to delay as they are packets base network services. Providing these services over the internet require high level of security to protect user, data and infrastructures. Encryption process is used to provide the security needed for RTA. The encryption and decryption has to take minimal time to achieve acceptable end-to-end delays. The research algorithm proposes a new symmetri...

  12. A new simultaneous compression and encryption method for images suitable to recognize form by optical correlation

    Alfalou, Ayman; Elbouz, Marwa; Jridi, Maher; Loussert, Alain

    2009-09-01

    In some recognition form applications (which require multiple images: facial identification or sign-language), many images should be transmitted or stored. This requires the use of communication systems with a good security level (encryption) and an acceptable transmission rate (compression rate). In the literature, several encryption and compression techniques can be found. In order to use optical correlation, encryption and compression techniques cannot be deployed independently and in a cascade manner. Otherwise, our system will suffer from two major problems. In fact, we cannot simply use these techniques in a cascade manner without considering the impact of one technique over another. Secondly, a standard compression can affect the correlation decision, because the correlation is sensitive to the loss of information. To solve both problems, we developed a new technique to simultaneously compress & encrypt multiple images using a BPOF optimized filter. The main idea of our approach consists in multiplexing the spectrums of different transformed images by a Discrete Cosine Transform (DCT). To this end, the spectral plane should be divided into several areas and each of them corresponds to the spectrum of one image. On the other hand, Encryption is achieved using the multiplexing, a specific rotation functions, biometric encryption keys and random phase keys. A random phase key is widely used in optical encryption approaches. Finally, many simulations have been conducted. Obtained results corroborate the good performance of our approach. We should also mention that the recording of the multiplexed and encrypted spectra is optimized using an adapted quantification technique to improve the overall compression rate.

  13. Application of Stochastic Diffusion for Hiding High Fidelity Encrypted Images

    Blackledge, Jonathan; Al-Rawi, AbdulRahman

    2011-01-01

    Cryptography coupled with information hiding has received increased attention in recent years and has become a major research theme because of the importance of protecting encrypted information in any Electronic Data Interchange system in a way that is both discrete and covert. One of the essential limitations in any cryptography system is that the encrypted data provides an indication on its importance which arouses suspicion and makes it vulnerable to attack. Information hiding of Steganogr...

  14. Grayscale image encryption using a hyperchaotic unstable dissipative system

    Ontanon-García, L.J.; García-Martínez, M.; Campos-Cantón, E.; Čelikovský, Sergej

    London: IEEE, 2013, s. 508-512. ISBN 978-1-908320-16-2. [The 8th International Conference for Internet Technology and Secured Transactions (ICITST-2013). Londýn (GB), 09.12.2013-12.12.2013] R&D Projects: GA ČR(CZ) GAP103/12/1794 Institutional support: RVO:67985556 Keywords : Hyperchaos * piecewise linear systems * multi-scrolls * chaotic encryption * stream cypher encryption Subject RIV: BC - Control Systems Theory

  15. Quantum Hash function and its application to privacy amplification in quantum key distribution, pseudo-random number generation and image encryption.

    Yang, Yu-Guang; Xu, Peng; Yang, Rui; Zhou, Yi-Hua; Shi, Wei-Min

    2016-01-01

    Quantum information and quantum computation have achieved a huge success during the last years. In this paper, we investigate the capability of quantum Hash function, which can be constructed by subtly modifying quantum walks, a famous quantum computation model. It is found that quantum Hash function can act as a hash function for the privacy amplification process of quantum key distribution systems with higher security. As a byproduct, quantum Hash function can also be used for pseudo-random number generation due to its inherent chaotic dynamics. Further we discuss the application of quantum Hash function to image encryption and propose a novel image encryption algorithm. Numerical simulations and performance comparisons show that quantum Hash function is eligible for privacy amplification in quantum key distribution, pseudo-random number generation and image encryption in terms of various hash tests and randomness tests. It extends the scope of application of quantum computation and quantum information. PMID:26823196

  16. Quantum Hash function and its application to privacy amplification in quantum key distribution, pseudo-random number generation and image encryption

    Yang, Yu-Guang; Xu, Peng; Yang, Rui; Zhou, Yi-Hua; Shi, Wei-Min

    2016-01-01

    Quantum information and quantum computation have achieved a huge success during the last years. In this paper, we investigate the capability of quantum Hash function, which can be constructed by subtly modifying quantum walks, a famous quantum computation model. It is found that quantum Hash function can act as a hash function for the privacy amplification process of quantum key distribution systems with higher security. As a byproduct, quantum Hash function can also be used for pseudo-random number generation due to its inherent chaotic dynamics. Further we discuss the application of quantum Hash function to image encryption and propose a novel image encryption algorithm. Numerical simulations and performance comparisons show that quantum Hash function is eligible for privacy amplification in quantum key distribution, pseudo-random number generation and image encryption in terms of various hash tests and randomness tests. It extends the scope of application of quantum computation and quantum information.

  17. A Novel Chaotic Map and an Improved Chaos-Based Image Encryption Scheme

    2014-01-01

    In this paper, we present a novel approach to create the new chaotic map and propose an improved image encryption scheme based on it. Compared with traditional classic one-dimensional chaotic maps like Logistic Map and Tent Map, this newly created chaotic map demonstrates many better chaotic properties for encryption, implied by a much larger maximal Lyapunov exponent. Furthermore, the new chaotic map and Arnold's Cat Map based image encryption method is designed and proved to be of solid robustness. The simulation results and security analysis indicate that such method not only can meet the requirement of imagine encryption, but also can result in a preferable effectiveness and security, which is usable for general applications. PMID:25143990

  18. Double image encryption based on random phase encoding in the fractional Fourier domain.

    Tao, Ran; Xin, Yi; Wang, Yue

    2007-11-26

    A novel image encryption method is proposed by utilizing random phase encoding in the fractional Fourier domain to encrypt two images into one encrypted image with stationary white distribution. By applying the correct keys which consist of the fractional orders, the random phase masks and the pixel scrambling operator, the two primary images can be recovered without cross-talk. The decryption process is robust against the loss of data. The phase-based image with a larger key space is more sensitive to keys and disturbances than the amplitude-based image. The pixel scrambling operation improves the quality of the decrypted image when noise perturbation occurs. The novel approach is verified by simulations. PMID:19550895

  19. Lossless Image Compression and Selective Encryption Using a Discrete Radon Transform

    Kingston, Andrew; Colosimo, Simone; Campisi, Patrizio; Autrusseau, Florent

    2007-01-01

    International audience In this paper we propose a new joint encryption and loss- less compression technique designed for large images 1 . The proposed technique takes advantage of the Mojette transform properties, and can easily be included in a distributed storage architecture. The basic crypto-compression scheme presented is based on a cascade of Radon projection which enables fast encryption of a large amount of digital data. Standard encryp- tion techniques, such as AES, DES, 3DES, or ...

  20. A Novel Bit-level Image Encryption Method Based on Chaotic Map and Dynamic Grouping

    张国基; 沈彦

    2012-01-01

    In this paper,a novel bit-level image encryption method based on dynamic grouping is proposed.In the proposed method,the plain-image is divided into several groups randomly,then permutation-diffusion process on bit level is carried out.The keystream generated by logistic map is related to the plain-image,which confuses the relationship between the plain-image and the cipher-image.The computer simulation results of statistical analysis,information entropy analysis and sensitivity analysis show that the proposed encryption method is secure and reliable enough to be used for communication application.

  1. Robust Encryption Algorithm Based Sht in Wireless Sensor Networks

    Uma.G

    2014-06-01

    Full Text Available In bound applications, the locations of events reportable by a device network have to be compelled to stay anonymous. That is, unauthorized observers should be unable to notice the origin of such events by analyzing the network traffic. I analyze 2 forms of downsides: Communication overhead and machine load problem. During this paper, I gift a brand new framework for modeling, analyzing, and evaluating obscurity in device networks. The novelty of the proposed framework is twofold: initial, it introduces the notion of “interval indistinguishability” and provides a quantitative live to model obscurity in wireless device networks; second, it maps supply obscurity to the applied mathematics downside I showed that the present approaches for coming up with statistically anonymous systems introduce correlation in real intervals whereas faux area unit unrelated. I show however mapping supply obscurity to consecutive hypothesis testing with nuisance Parameters ends up in changing the matter of exposing non-public supply data into checking out associate d egree applicable knowledge transformation that removes or minimize the impact of the nuisance data victimization sturdy cryptography algorithmic rule. By doing therefore, I remodel the matter of analyzing real valued sample points to binary codes, that opens the door for committal to writing theory to be incorporated into the study of anonymous etworks. In existing work, unable to notice unauthorized observer in network traffic. However our work in the main supported enhances their supply obscurity against correlation check. the most goal of supply location privacy is to cover the existence of real events.

  2. Multi-image encryption based on synchronization of chaotic lasers and iris authentication

    Banerjee, Santo; Mukhopadhyay, Sumona; Rondoni, Lamberto

    2012-07-01

    A new technique of transmitting encrypted combinations of gray scaled and chromatic images using chaotic lasers derived from Maxwell-Bloch's equations has been proposed. This novel scheme utilizes the general method of solution of a set of linear equations to transmit similar sized heterogeneous images which are a combination of monochrome and chromatic images. The chaos encrypted gray scaled images are concatenated along the three color planes resulting in color images. These are then transmitted over a secure channel along with a cover image which is an iris scan. The entire cryptology is augmented with an iris-based authentication scheme. The secret messages are retrieved once the authentication is successful. The objective of our work is briefly outlined as (a) the biometric information is the iris which is encrypted before transmission, (b) the iris is used for personal identification and verifying for message integrity, (c) the information is transmitted securely which are colored images resulting from a combination of gray images, (d) each of the images transmitted are encrypted through chaos based cryptography, (e) these encrypted multiple images are then coupled with the iris through linear combination of images before being communicated over the network. The several layers of encryption together with the ergodicity and randomness of chaos render enough confusion and diffusion properties which guarantee a fool-proof approach in achieving secure communication as demonstrated by exhaustive statistical methods. The result is vital from the perspective of opening a fundamental new dimension in multiplexing and simultaneous transmission of several monochromatic and chromatic images along with biometry based authentication and cryptography.

  3. RSA加密算法中MPI的应用%Application of MPI in RSA encryption algorithm

    陆玉阳

    2015-01-01

    RSA加密算法在进行复杂判断和大数运算时,计算时间往往花费较多,对计算机的运行速度、存储容量等方面具有较高的要求.MPI能够提供较快的数值计算和数据处理能力,提供高性能并行计算.该文通过在RSA加密算法中MPI的应用,通过实践证明MPI并行计算可以改进RSA算法,提高加密速度、减少容量需求等.%RSA encryption algorithm in the complex judgment and operation of large Nbers, calculating the time tend to spend more, the computer run faster, have higher requirements in terms of storage capacity. MPI provides fast Nerical calculation and data processing capability, providing high performance parallel computing. Based on RSA encryption algorithm in application of MPI, MPI parallel computing can improve the RSA algorithm proved by practice, increase speed, reduce capacity requirements, and so on.

  4. A New Loss-Tolerant Image Encryption Scheme Based on Secret Sharing and Two Chaotic Systems

    Li Li

    2012-04-01

    Full Text Available In this study, we propose an efficient loss-tolerant image encryption scheme that protects both confidentiality and loss-tolerance simultaneously in shadow images. In this scheme, we generate the key sequence based on two chaotic maps and then encrypt the image during the sharing phase based on Shamir’s method. Experimental results show a better performance of the proposed scheme for different images than other methods from human vision. Security analysis confirms a high probability to resist both brute-force and collusion attacks.

  5. Medical Images Watermarking Algorithm Based on Improved DCT

    Yv-fan SHANG; Yi-ning KANG

    2013-01-01

    Targeting at the incessant securities problems of digital information management system in modern medical system, this paper presents the robust watermarking algorithm for medical images based on Arnold transformation and DCT. The algorithm first deploys the scrambling technology to encrypt the watermark information and then combines it with the visual feature vector of the image to generate a binary logic series through the hash function. The sequence as taken as keys and stored in the third...

  6. Evaluation of security algorithms used for security processing on DICOM images

    Chen, Xiaomeng; Shuai, Jie; Zhang, Jianguo; Huang, H. K.

    2005-04-01

    In this paper, we developed security approach to provide security measures and features in PACS image acquisition and Tele-radiology image transmission. The security processing on medical images was based on public key infrastructure (PKI) and including digital signature and data encryption to achieve the security features of confidentiality, privacy, authenticity, integrity, and non-repudiation. There are many algorithms which can be used in PKI for data encryption and digital signature. In this research, we select several algorithms to perform security processing on different DICOM images in PACS environment, evaluate the security processing performance of these algorithms, and find the relationship between performance with image types, sizes and the implementation methods.

  7. Optical image encryption based on multi-beam interference and common vector decomposition

    Chen, Linfei; He, Bingyu; Chen, Xudong; Gao, Xiong; Liu, Jingyu

    2016-02-01

    Based on multi-beam interference and common vector decomposition, we propose a new method for optical image encryption. In encryption process, the information of an original image is encoded into n amplitude masks and n phase masks which are regarded as a ciphertext and many keys. In decryption process, parallel light irradiates the amplitude masks and phase masks, then passes through lens that takes place Fourier transform, and finally we obtain the original image at the output plane after interference. The security of the encryption system is also discussed in the paper, and we find that only when all the keys are correct, can the information of the original image be recovered. Computer simulation results are presented to verify the validity and the security of the proposed method.

  8. A secure image encryption method based on dynamic harmony search (DHS) combined with chaotic map

    Mirzaei Talarposhti, Khadijeh; Khaki Jamei, Mehrzad

    2016-06-01

    In recent years, there has been increasing interest in the security of digital images. This study focuses on the gray scale image encryption using dynamic harmony search (DHS). In this research, first, a chaotic map is used to create cipher images, and then the maximum entropy and minimum correlation coefficient is obtained by applying a harmony search algorithm on them. This process is divided into two steps. In the first step, the diffusion of a plain image using DHS to maximize the entropy as a fitness function will be performed. However, in the second step, a horizontal and vertical permutation will be applied on the best cipher image, which is obtained in the previous step. Additionally, DHS has been used to minimize the correlation coefficient as a fitness function in the second step. The simulation results have shown that by using the proposed method, the maximum entropy and the minimum correlation coefficient, which are approximately 7.9998 and 0.0001, respectively, have been obtained.

  9. A Technique for Image Encryption with Combination of Pixel Rearrangement Scheme Based On Sorting Group-Wise Of RGB Values and Explosive Inter-Pixel Displacement

    Amnesh Goel; Nidhi Chandra

    2012-01-01

    Encryption is used to prevent data from unauthorized access and with the appalling headway in network technology seen in the past decade; it has become the need of time to encrypt the images before sending over open network. Though researchers has proposed contrastive methods to encrypt images but correlation between pixels RGB value play a imperative part to guess for original image. So, here we introduce a new image encryption method which first rearranges the pixels within image on basis o...

  10. Dynamic video encryption algorithm for H.264/AVC based on a spatiotemporal chaos system.

    Xu, Hui; Tong, Xiao-Jun; Zhang, Miao; Wang, Zhu; Li, Ling-Hao

    2016-06-01

    Video encryption schemes mostly employ the selective encryption method to encrypt parts of important and sensitive video information, aiming to ensure the real-time performance and encryption efficiency. The classic block cipher is not applicable to video encryption due to the high computational overhead. In this paper, we propose the encryption selection control module to encrypt video syntax elements dynamically which is controlled by the chaotic pseudorandom sequence. A novel spatiotemporal chaos system and binarization method is used to generate a key stream for encrypting the chosen syntax elements. The proposed scheme enhances the resistance against attacks through the dynamic encryption process and high-security stream cipher. Experimental results show that the proposed method exhibits high security and high efficiency with little effect on the compression ratio and time cost. PMID:27409446

  11. A Lightweight White-Box Symmetric Encryption Algorithm against Node Capture for WSNs

    Yang Shi

    2015-05-01

    Full Text Available Wireless Sensor Networks (WSNs are often deployed in hostile environments and, thus, nodes can be potentially captured by an adversary. This is a typical white-box attack context, i.e., the adversary may have total visibility of the implementation of the build-in cryptosystem and full control over its execution platform. Handling white-box attacks in a WSN scenario is a challenging task. Existing encryption algorithms for white-box attack contexts require large memory footprint and, hence, are not applicable for wireless sensor networks scenarios. As a countermeasure against the threat in this context, in this paper, we propose a class of lightweight secure implementations of the symmetric encryption algorithm SMS4. The basic idea of our approach is to merge several steps of the round function of SMS4 into table lookups, blended by randomly generated mixing bijections. Therefore, the size of the implementations are significantly reduced while keeping the same security efficiency. The security and efficiency of the proposed solutions are theoretically analyzed. Evaluation shows our solutions satisfy the requirement of sensor nodes in terms of limited memory size and low computational costs.

  12. Medical Image Encryption and Compression Scheme Using Compressive Sensing and Pixel Swapping Based Permutation Approach

    Li-bo Zhang

    2015-01-01

    Full Text Available This paper presents a solution to satisfy the increasing requirements for secure medical image transmission and storage over public networks. The proposed scheme can simultaneously encrypt and compress the medical image using compressive sensing (CS and pixel swapping based permutation approach. In the CS phase, the plain image is compressed and encrypted by chaos-based Bernoulli measurement matrix, which is generated under the control of the introduced Chebyshev map. The quantized measurements are then encrypted by permutation-diffusion type chaotic cipher for the second level protection. Simulations and extensive security analyses have been performed. The results demonstrate that at a large scale of compression ratio the proposed cryptosystem can provide satisfactory security level and reconstruction quality.

  13. 采用混沌函数的图像加密算法%Image Encryption Based on a Chaos Function

    马金发

    2012-01-01

    A novel efficient algorithm is proposed to encrypt images using the combine chaos function and XOR operator. This algorithm can produce a large key space to resist attacks, and encrypt securely images. The proposed algorithm exhibits extreme sensitivity to key and original image, and the cipher image has high non-correlation among pixels, and the ciphers have a high level of randomness. The experimental results show that the algorithm is efficient and secure enough to be used for the image encryption.%提出一种新的图像加密算法,采用混沌函数与“按位异或”操作相结合的方法对图像加密.该算法能够产生一个较大的密钥空间足以抵御外力攻击,能够安全地对图像加密,并具有很强的对密钥和原图像的敏感性,密文图像具有高度的非相关性,而密文具有良好的随机性.实验结果验证了算法的有效性,可以满足图像安全加密的要求.

  14. Image encryption based on a delayed fractional-order chaotic logistic system

    Wang Zhen; Huang Xia; Li Ning; Song Xiao-Na

    2012-01-01

    A new image encryption scheme is proposed based on a delayed fractional-order chaotic logistic system.In the process of generating a key stream,the time-varying delay and fractional derivative are embedded in the proposed scheme to improve the security.Such a scheme is described in detail with security analyses including correlation analysis,information entropy analysis,run statistic analysis,mean-variance gray value analysis,and key sensitivity analysis.Experimental results show that the newly proposed image encryption scheme possesses high security.

  15. Cryptanalysis and improvement of a digital image encryption method with chaotic map lattices

    Wang Xing-Yuan; Liu Lin-Tao

    2013-01-01

    A digital image encryption scheme using chaotic map lattices has been proposed recently.In this paper,two fatal flaws of the cryptosystem are pointed out.According to these two drawbacks,cryptanalysts could recover the plaintext by applying the chosen plaintext attack.Therefore,the proposed cryptosystem is not secure enough to be used in the image transmission system.Experimental results show the feasibility of the attack.As a result,we make some improvements to the encryption scheme,which can completely resist our chosen plaintext attack.

  16. Image encryption based on a delayed fractional-order chaotic logistic system

    A new image encryption scheme is proposed based on a delayed fractional-order chaotic logistic system. In the process of generating a key stream, the time-varying delay and fractional derivative are embedded in the proposed scheme to improve the security. Such a scheme is described in detail with security analyses including correlation analysis, information entropy analysis, run statistic analysis, mean-variance gray value analysis, and key sensitivity analysis. Experimental results show that the newly proposed image encryption scheme possesses high security. (general)

  17. Lag Synchronization of Switched Neural Networks via Neural Activation Function and Applications in Image Encryption.

    Wen, Shiping; Zeng, Zhigang; Huang, Tingwen; Meng, Qinggang; Yao, Wei

    2015-07-01

    This paper investigates the problem of global exponential lag synchronization of a class of switched neural networks with time-varying delays via neural activation function and applications in image encryption. The controller is dependent on the output of the system in the case of packed circuits, since it is hard to measure the inner state of the circuits. Thus, it is critical to design the controller based on the neuron activation function. Comparing the results, in this paper, with the existing ones shows that we improve and generalize the results derived in the previous literature. Several examples are also given to illustrate the effectiveness and potential applications in image encryption. PMID:25594985

  18. A novel chaotic based image encryption using a hybrid model of deoxyribonucleic acid and cellular automata

    Enayatifar, Rasul; Sadaei, Hossein Javedani; Abdullah, Abdul Hanan; Lee, Malrey; Isnin, Ismail Fauzi

    2015-08-01

    Currently, there are many studies have conducted on developing security of the digital image in order to protect such data while they are sending on the internet. This work aims to propose a new approach based on a hybrid model of the Tinkerbell chaotic map, deoxyribonucleic acid (DNA) and cellular automata (CA). DNA rules, DNA sequence XOR operator and CA rules are used simultaneously to encrypt the plain-image pixels. To determine rule number in DNA sequence and also CA, a 2-dimension Tinkerbell chaotic map is employed. Experimental results and computer simulations, both confirm that the proposed scheme not only demonstrates outstanding encryption, but also resists various typical attacks.

  19. High performance optical encryption based on computational ghost imaging with QR code and compressive sensing technique

    Zhao, Shengmei; Wang, Le; Liang, Wenqiang; Cheng, Weiwen; Gong, Longyan

    2015-10-01

    In this paper, we propose a high performance optical encryption (OE) scheme based on computational ghost imaging (GI) with QR code and compressive sensing (CS) technique, named QR-CGI-OE scheme. N random phase screens, generated by Alice, is a secret key and be shared with its authorized user, Bob. The information is first encoded by Alice with QR code, and the QR-coded image is then encrypted with the aid of computational ghost imaging optical system. Here, measurement results from the GI optical system's bucket detector are the encrypted information and be transmitted to Bob. With the key, Bob decrypts the encrypted information to obtain the QR-coded image with GI and CS techniques, and further recovers the information by QR decoding. The experimental and numerical simulated results show that the authorized users can recover completely the original image, whereas the eavesdroppers can not acquire any information about the image even the eavesdropping ratio (ER) is up to 60% at the given measurement times. For the proposed scheme, the number of bits sent from Alice to Bob are reduced considerably and the robustness is enhanced significantly. Meantime, the measurement times in GI system is reduced and the quality of the reconstructed QR-coded image is improved.

  20. A fast image encryption system based on chaotic maps with finite precision representation

    In this paper, a fast chaos-based image encryption system with stream cipher structure is proposed. In order to achieve a fast throughput and facilitate hardware realization, 32-bit precision representation with fixed point arithmetic is assumed. The major core of the encryption system is a pseudo-random keystream generator based on a cascade of chaotic maps, serving the purpose of sequence generation and random mixing. Unlike the other existing chaos-based pseudo-random number generators, the proposed keystream generator not only achieves a very fast throughput, but also passes the statistical tests of up-to-date test suite even under quantization. The overall design of the image encryption system is to be explained while detail cryptanalysis is given and compared with some existing schemes

  1. Towards Symbolic Encryption Schemes

    Ahmed, Naveed; Jensen, Christian D.; Zenner, Erik

    Symbolic encryption, in the style of Dolev-Yao models, is ubiquitous in formal security models. In its common use, encryption on a whole message is specified as a single monolithic block. From a cryptographic perspective, however, this may require a resource-intensive cryptographic algorithm......-known Needham-Schroeder and Denning-Sacco protocols. To avoid such problems, we advocate the use of refined notions of symbolic encryption that have natural correspondence to standard cryptographic encryption schemes....

  2. Hybrid Encryption-Compression Scheme Based on Multiple Parameter Discrete Fractional Fourier Transform with Eigen Vector Decomposition Algorithm

    Deepak Sharma

    2014-09-01

    Full Text Available Encryption along with compression is the process used to secure any multimedia content processing with minimum data storage and transmission. The transforms plays vital role for optimizing any encryption-compression systems. Earlier the original information in the existing security system based on the fractional Fourier transform (FRFT is protected by only a certain order of FRFT. In this article, a novel method for encryption-compression scheme based on multiple parameters of discrete fractional Fourier transform (DFRFT with random phase matrices is proposed. The multiple-parameter discrete fractional Fourier transform (MPDFRFT possesses all the desired properties of discrete fractional Fourier transform. The MPDFRFT converts to the DFRFT when all of its order parameters are the same. We exploit the properties of multiple-parameter DFRFT and propose a novel encryption-compression scheme using the double random phase in the MPDFRFT domain for encryption and compression data. The proposed scheme with MPDFRFT significantly enhances the data security along with image quality of decompressed image compared to DFRFT and FRFT and it shows consistent performance with different images. The numerical simulations demonstrate the validity and efficiency of this scheme based on Peak signal to noise ratio (PSNR, Compression ratio (CR and the robustness of the schemes against bruit force attack is examined.

  3. A NEW TECHNIQUE BASED ON CHAOTIC STEGANOGRAPHY AND ENCRYPTION TEXT IN DCT DOMAIN FOR COLOR IMAGE

    MELAD J. SAEED

    2013-10-01

    Full Text Available Image steganography is the art of hiding information into a cover image. This paper presents a new technique based on chaotic steganography and encryption text in DCT domain for color image, where DCT is used to transform original image (cover image from spatial domain to frequency domain. This technique used chaotic function in two phases; firstly; for encryption secret message, second; for embedding in DCT cover image. With this new technique, good results are obtained through satisfying the important properties of steganography such as: imperceptibility; improved by having mean square error (MSE, peak signal to noise ratio (PSNR and normalized correlation (NC, to phase and capacity; improved by encoding the secret message characters with variable length codes and embedding the secret message in one level of color image only.

  4. An Image Encryption Scheme Based on Hyperchaotic Rabinovich and Exponential Chaos Maps

    Xiaojun Tong

    2015-01-01

    Full Text Available This paper proposes a new four-dimensional hyperchaotic map based on the Rabinovich system to realize chaotic encryption in higher dimension and improve the security. The chaotic sequences generated by Runge-Kutta method are combined with the chaotic sequences generated by an exponential chaos map to generate key sequences. The key sequences are used for image encryption. The security test results indicate that the new hyperchaotic system has high security and complexity. The comparison between the new hyperchaotic system and the several low-dimensional chaotic systems shows that the proposed system performs more efficiently.

  5. Multidimensional Z-Matrix with Control Parameters and Its Applications in Image Encryption

    ZHAO Liang; LIAO Xiao-Feng; XIANG Tao; XIAO Di

    2009-01-01

    An n-dimensional Z-matrix with control parameters is presented,and its periodicity and chaos are testified.Experimental results show that the proposed Z-matrix has a long period and changeable periodicity with different dimensions.Some examples of image encryption with a Z-matrix of different dimensions are listed for demonstrating its appfications.

  6. On the security of gyrator transform-based image encryption by chosen-plaintext attack

    Sang, Jun; Alam, Mohammad S.; Cai, Bin

    2016-04-01

    For the gyrator transform-based image encryption, besides the random operations, the rotation angles used in the gyrator transforms are also taken as the secret keys, which makes such cryptosystems to be more secure. To analyze the security of such cryptosystems, one may start from analyzing the security of a single gyrator transform. In this paper, the security of the gyrator transform-based image encryption by chosen-plaintext attack was discussed in theory. By using the impulse functions as the chosen-plaintext, it was concluded that: (1) For a single gyrator transform, by choosing a plaintext, the rotation angle can be obtained very easily and efficiently; (2) For image encryption with a single random phase encoding and a single gyrator transform, it is hard to find the rotation angle directly with a chosen-plaintext attack. However, assuming the value of one of the elements in the random phase mask is known, the rotation angle can be obtained very easily with a chosen-plaintext attack, and the random phase mask can also be recovered. Furthermore, by exhaustively searching the value of one of the elements in the random phase mask, the rotation angle as well as the random phase mask may be recovered. By obtaining the relationship between the rotation angle and the random phase mask for image encryption with a single random phase encoding and a single gyrator transform, it may be useful for further study on the security of the iterative random operations in the gyrator transform domains.

  7. An RSA Encryption Hardware Algorithm using a Single DSP Block and a Single Block RAM on the FPGA

    Koji Nakano

    2011-07-01

    Full Text Available The main contribution of this paper is to present an efficient hardware algorithm for RSA encryption/decryption based on Montgomery multiplication. Modern FPGAs have a number of embedded DSP blocks (DSP48E1 and embedded memory blocks (BRAM. Our hardware algorithm supporting 2048-bit RSA encryption/decryption is designed to be implemented using one DSP48E1, one BRAM and few logic blocks (slices in the Xilinx Virtex-6 family FPGA. The implementation results showed that our RSA module for 2048-bit RSA encryption/decryption runs in 277.26ms. Quite surprisingly, the multiplier in DSP48E1 used to compute Montgomery multiplication works in more than 97% clock cycles over all clock cycles. Hence, our implementation is close to optimal in the sense that it has only less than 3% overhead in multiplication and no further improvement is possible as long as Montgomery multiplication based algorithm is used. Also, since our circuit uses only one DSP48E1 block and one Block RAM, we can implement a number of RSA modules in an FPGA that can work in parallel to attain high throughput RSA encryption/decryption.

  8. Optical Image Addition and Encryption by Multi-Exposure Based on Fractional Fourier Transform Hologram

    CHEN Lin-Fei; ZHAO Dao-Mu

    2006-01-01

    @@ We propose a new method to add different images together by optical implementation that is realized by the multi-exposure based on fractional Fourier transform hologram. Partial image fusion is proposed and realized by this method. Multiple images encryption can also be implemented by the multi-exposure of the hologram based on fractional Fourier transform. Computer simulations prove that this method is valid.

  9. 基于MD5的可逆无冗余加密算法%The Reversible Non-Redundant Encryption Algorithm Based on MD5 Algorithm

    陈钧; 刘爱华

    2012-01-01

    If MD5 algorithm is directly used to encrypt sensitive data in database, the data is unable to be deerypted by this algorithm itself, even legitimate users query or update some data for the purpose of restoring data. The database becomes more redundant because secret keys need to be saved for reversible encryption algorithms. This paper proposes a reversible non-redundant encryption algorithm based on MD5 algorithm, which can be ~ to used encrypt and decrypt sensitive data in the database regardless of saving secret keys.%直接采用MD5算法对数据库中的敏感数据加密时,合法用户进行查询、更新等操作需要还原数据,MD5算法无法解密数据.可逆的加密算法都需要保存密钥,数据库增加了数据的冗余.本文提出一种基于MD5算法的可逆无冗余算法,实现对数据库中敏感数据进行加密、解密,而且不需要保存密钥.

  10. Interference-based image encryption with silhouette removal by aid of compressive sensing

    Gong, Qiong; Wang, Zhipeng; Lv, Xiaodong; Qin, Yi

    2016-01-01

    Compressive sensing (CS) offers the opportunity to reconstruct a signal from its sparse representation, either in the space domain or the transform domain. Exploiting this character, we propose a simple interference-based image encryption method. For encryption, a synthetic image, which contains sparse samples of the original image and the designated values, is analytically separated into two phase only masks (POMs). Consequently, only fragmentary data of the primary image can be directly collected in the traditional decryption scheme. However, the subsequent CS reconstruction will retrieve a high quality image from the fragmentary information. The proposed method has effectively suppressed the silhouette problem. Moreover, it has also some distinct advantages over the previous approaches.

  11. System for Information Encryption Implementing Several Chaotic Orbits

    Jiménez-Rodríguez Maricela

    2015-07-01

    Full Text Available This article proposes a symmetric encryption algorithm that takes, as input value, the original information of length L, that when encoded, generates the ciphertext of greater length LM. A chaotic discrete system (logistic map is implemented to generate 3 different orbits: the first is used for applying a diffusion technique in order to mix the original data, the second orbit is combined with the mixed information and increases the length of L to LM, and with the third orbit, the confusion technique is implemented. The encryption algorithm was applied to encode an image which is then totally recovered by the keys used to encrypt and his respective, decrypt algorithm. The algorithm can encode any information, just dividing into 8 bits, it can cover the requirements for high level security, it uses 7 keys to encrypt and provides good encryption speed

  12. Color image encryption using iterative phase retrieve process in quaternion Fourier transform domain

    Sui, Liansheng; Duan, Kuaikuai

    2015-02-01

    A single-channel color image encryption method is proposed based on iterative phase iterative process in quaternion Fourier transform domain. First, three components of the plain color image is confused respectively by using cat map. Second, the confused components are combined into a pure quaternion image, which is encode to the phase only function by using an iterative phase retrieval process. Finally, the phase only function is encrypted into the gray scale ciphertext with stationary white noise distribution based on the chaotic diffusion, which has camouflage property to some extent. The corresponding plain color image can be recovered from the ciphertext only with correct keys in the decryption process. Simulation results verify the feasibility and effectiveness of the proposed method.

  13. Triple-image encryption based on phase-truncated Fresnel transform and basic vector operation.

    Pan, Xuemei; Meng, Xiangfeng; Yang, Xiulun; Wang, Yurong; Peng, Xiang; He, Wenqi; Dong, Guoyan; Chen, Hongyi

    2015-10-01

    A triple-image encryption method is proposed that is based on phase-truncated Fresnel transform (PTFT), basic vector composition, and XOR operation. In the encryption process, two random phase masks, with one each placed at the input plane and the transform plane, are generated by basic vector resolution operations over the first and the second plaintext images, and then a ciphered image in the input plane is fabricated by XOR encoding for the third plaintext image. When the cryptosystem is illuminated by an on-axis plane, assisted by PTFT, the ciphered image is finally encrypted into an amplitude-only noise-like image in the output plane. During decryption, possessing the correct private key, decryption keys, and the assistant geometrical parameter keys, and placing them at the corresponding correct positions, the original three plaintext images can be successfully decrypted by inverse PTFT, basic vector composition, and XOR decoding. Theoretical analysis and numerical simulations both verify the feasibility of the proposed method. PMID:26479627

  14. Image encryption schemes for JPEG and GIF formats based on 3D baker with compound chaotic sequence generator

    Ji, Shiyu; Tong, Xiaojun; Zhang, Miao

    2012-01-01

    This paper proposed several methods to transplant the compound chaotic image encryption scheme with permutation based on 3D baker into image formats as Joint Photographic Experts Group (JPEG) and Graphics Interchange Format (GIF). The new method averts the lossy Discrete Cosine Transform and quantization and can encrypt and decrypt JPEG images lossless. Our proposed method for GIF keeps the property of animation successfully. The security test results indicate the proposed methods have high s...

  15. Multiple Image Encryption Technology Based on Logistic Mapping%基于Logistic映射的多重图像加密技术

    王琳娟

    2011-01-01

    利用Logistic混沌序列的随机性、对初始条件敏感及迭代不重复的特性,对数字图像进行空域像素值扰乱和小波变换域系数位置置乱实现图像的多重加密.首先利用产生的混沌序列进行图像像素值的扰乱,然后利用扩散变换对像素值进一步扰乱,最后再产生一组混沌序列对小波系数进行位置置乱,并对置乱后的小波系数重构得到加密图像.实验证明:文中算法扰乱了图像的直方图分布,使得加密图像能够抵抗明文统计的攻击,且密钥空间大,具有很好的加密效果.%The Logistic chaotic sequence is famous for its randomness, the sensitive of the original value and non-repeatability of iteration. A multiple image encryption technology based on scrambling the pixel value of original image and the position of wavelet coefficients are presented. Firstly, the pixel value of original image by using the chaotic sequences based on logistic mapping are modified. Secondly, the pixel value is further scrambled by using diffusion transformation. At last, in order to encrypt the image again, wavelet analysis to improve the performance of encryption are used. The location of wavelet coefficients are changed using another logistic chaotic sequence. An encrypted image is obtained by reconstructing the scrambled wavelet coefficients. The test results show the algorithm disturbs the histogram distribution of original image which enables the encrypted image can resist the statistics attack of known-plaintext. And the algorithm can realize the image encryption with larger key space and good effect.

  16. Triple Layered Encryption Algorithm for IEEE 802.11 WLANs in E-Government Services

    M A Kabir

    2013-09-01

    Full Text Available Wireless local area network (WLAN can provide e-government services at all levels, from local to national as the WLAN enabled devices have the flexibility to move from one place to another within offices while maintaining connectivity with the network. However, government organizations are subject to strict security policies and other compliance requirements. Therefore, WLAN must ensure the safeguard the privacy of individual data with the strictest levels of security. The 802.11 MAC specifications describe an encryption protocol called Wired Equivalent Privacy (WEP which is used to protect wireless communications from eavesdropping. It is also capable of preventing unauthorized access. However, the WEP protocol often fails to accomplish its security goal due to the weakness in RC4 and the way it is applied in WEP protocol. This paper focuses the improvement of existing WEP protocol using the varying secret key for each transmission. This will remove the insecurities that currently make the RC4 unattractive for secured networking and this will add further cryptographic strength if applied to Rijndael algorithm. Our result shows that the proposed algorithm is more suitable for small and medium packets and AES for large packets.

  17. Digital Watermarking through Embedding of Encrypted and Arithmetically Compressed Data into Image using Variable-Length Key

    Sabyasachi Samanta

    2011-03-01

    Full Text Available In this paper, we have encrypted a text to an array of data bits through arithmetic coding technique. Forthis, we have assigned a unique range for both, a number of characters and groups using those. Usingunique range we may assign range only 10 characters. If we want to encrypt a large number ofcharacters, then every character has to assign a range with their group range of hundred, thousand andso on. Long textual message which have to encrypt, is subdivided into a number of groups with fewcharacters. Then the group of characters is encrypted into floating point numbers concurrently to theirgroup range by using arithmetic coding, where they are automatically compressed. Depending on key,the data bits from text are placed to some suitable nonlinear pixel and bit positions about the image. Inthe proposed technique, the key length and the number of characters for any encryption process is bothvariable.

  18. Fast encryption of RGB color digital images using a tweakable cellular automaton based schema

    Faraoun, Kamel Mohamed

    2014-12-01

    We propose a new tweakable construction of block-enciphers using second-order reversible cellular automata, and we apply it to encipher RGB-colored images. The proposed construction permits a parallel encryption of the image content by extending the standard definition of a block cipher to take into account a supplementary parameter used as a tweak (nonce) to control the behavior of the cipher from one region of the image to the other, and hence avoid the necessity to use slow sequential encryption's operating modes. The proposed construction defines a flexible pseudorandom permutation that can be used with efficacy to solve the electronic code book problem without the need to a specific sequential mode. Obtained results from various experiments show that the proposed schema achieves high security and execution performances, and enables an interesting mode of selective area decryption due to the parallel character of the approach.

  19. A New Image Encryption Scheme Based on Dynamic S-Boxes and Chaotic Maps

    Rehman, Atique Ur; Khan, Jan Sher; Ahmad, Jawad; Hwang, Soeng Oun

    2016-03-01

    Substitution box is a unique and nonlinear core component of block ciphers. A better designing technique of substitution box can boost up the quality of ciphertexts. In this paper, a new encryption method based on dynamic substitution boxes is proposed via using two chaotic maps. To break the correlation in an original image, pixels values of the original plaintext image are permuted row- and column-wise through random sequences. The aforementioned random sequences are generated by 2-D Burgers chaotic map. For the generation of dynamic substitution boxes, Logistic chaotic map is employed. In the process of diffusion, the permuted image is divided into blocks and each block is substituted via different dynamic substitution boxes. In contrast to conventional encryption schemes, the proposed scheme does not undergo the fixed block cipher and hence the security level can be enhanced. Extensive security analysis including histogram test is applied on the proposed image encryption technique. All experimental results reveal that the proposed scheme has a high level of security and robustness for transmission of digital images on insecure communication channels.

  20. A Systematic Methodology for Multi-Images Encryption and Decryption Based on Single Chaotic System and FPGA Embedded Implementation

    Hanzhong Zheng; Simin Yu; Xiangqian Xu

    2014-01-01

    A systematic methodology is developed for multi-images encryption and decryption and field programmable gate array (FPGA) embedded implementation by using single discrete time chaotic system. To overcome the traditional limitations that a chaotic system can only encrypt or decrypt one image, this paper initiates a new approach to design n-dimensional (n-D) discrete time chaotic controlled systems via some variables anticontrol, which can achieve multipath drive-response synchronization. To th...

  1. Image encryption and authentication. A fully digital approach

    Optical surveillance is one of the basic safeguards measures implemented by the IAEA. If it were possible to have the data carriers replaced and mailed to the IAEA by staff of the State System for Accounting and Control (SSAC) or by the facility operator or, ultimately have the data remotely transmitted to IAEA Headquarters, this would enable the frequency of on-site inspections to be reduced, since the surveillance information would still be available in a timely manner for evaluation at HQ. The IAEA needs to verify the authenticity of the data, whereas the facility operator will insist on the confidentiality of the data; i.e. a third party must not be able to make any use of the data transferred. The present development effort is concentrated on the appropriate camera electronics ensuring uninterrupted electronic authentication and encryption of the video signals from the camera up to the review station. The design concept is described, some crucial aspects are discussed, and the status and perspectives of the project reported. (author). 4 refs, 2 figs

  2. An Image Encryption Method Based on Bit Plane Hiding Technology

    LIU Bin; LI Zhitang; TU Hao

    2006-01-01

    A novel image hiding method based on the correlation analysis of bit plane is described in this paper. Firstly, based on the correlation analysis, different bit plane of a secret image is hided in different bit plane of several different open images. And then a new hiding image is acquired by a nesting "Exclusive-OR" operation on those images obtained from the first step. At last, by employing image fusion technique, the final hiding result is achieved. The experimental result shows that the method proposed in this paper is effective.

  3. Analysis on MARS and RC6 Encryption Algorithms%MARS算法和RC6算法分析

    王镭; 陈克非

    2001-01-01

    介绍了入围AES第二轮的MARS算法和RC6算法,通过对这两个算法的研究和比较,分析分组加密算法设计特点和趋势,供研究者参考.%In this paper, authors introduce MARS and RC6 encryption algorithms which enter the second round of AES. By ana lysing and comparing these two algorithms, we find some features and tendency of designing symmetric block cipher for researchers

  4. Medical Images Watermarking Algorithm Based on Improved DCT

    Yv-fan SHANG

    2013-12-01

    Full Text Available Targeting at the incessant securities problems of digital information management system in modern medical system, this paper presents the robust watermarking algorithm for medical images based on Arnold transformation and DCT. The algorithm first deploys the scrambling technology to encrypt the watermark information and then combines it with the visual feature vector of the image to generate a binary logic series through the hash function. The sequence as taken as keys and stored in the third party to obtain ownership of the original image. Having no need for artificial selection of a region of interest, no capacity constraint, no participation of the original medical image, such kind of watermark extracting solves security and speed problems in the watermark embedding and extracting. The simulation results also show that the algorithm is simple in operation and excellent in robustness and invisibility. In a word, it is more practical compared with other algorithms

  5. A New Public-Key Encryption Scheme Based on Non-Expansion Visual Cryptography and Boolean Operation

    Abdullah M. Jaafar; Azman Samsudin

    2010-01-01

    Currently, most of the existing public-key encryption schemes are based on complex algorithms with heavy computations. In 1994, Naor and Shamir proposed a simple cryptography method for digital images called visual cryptography. Existing visual cryptography primitives can be considered as a special kind of secret-key cryptography that does not require heavy computations for encrypting and decrypting an image. In this paper, we propose a new public-key encryption scheme for image based on non-...

  6. Comment: Cryptanalysis of an image encryption scheme based on the Hill cipher

    Cheng-qing LI; Dan ZHANG; Guan-rong CHEN

    2008-01-01

    This paper studies the security of an image encryption scheme based on the Hill cipher (Ismail et al.,2006) and reports its following problems:(1) There is a simple necessary and sufficient condition that makes a number of secret keys invalid;(2) It is insensitive to the change of the secret key;(3) It is insensitive to the change of the plain-image;(4) It can be broken with only one known/chosen plaintext;(5) It has some other minor defects.The proposed cryptanalysis discourages any use of the scheme in practice.

  7. A Modified Location-Dependent Image Encryption for Mobile Information System

    Prasad Reddy P.V.G.D; K.R.Sudha; P Sanyasi Naidu

    2010-01-01

    The wide spread use of WLAN (Wireless LAN) and the popularity of mobile devices increases the frequency of data transmission among mobile users. In such scenario, a need for Secure Communication arises. Secure communication is possible through encryption of data. A lot of encryption techniques have evolved over time. However, most of the data encryption techniques are location-independent. Data encrypted with such techniques can be decrypted anywhere. The encryption technology cannot restrict...

  8. A Comparison between Memetic algorithm and Genetic algorithm for the cryptanalysis of Simplified Data Encryption Standard algorithm

    Poonam Garg

    2010-01-01

    Genetic algorithms are a population-based Meta heuristics. They have been successfully applied to many optimization problems. However, premature convergence is an inherent characteristic of such classical genetic algorithms that makes them incapable of searching numerous solutions of the problem domain. A memetic algorithm is an extension of the traditional genetic algorithm. It uses a local search technique to reduce the likelihood of the premature convergence. The cryptanalysis of simplifie...

  9. 基于复用技术和数论的图像加密压缩同步算法%Simultaneous Image Compression and Encryption Using Number Theory and Image Multiplexing

    郭雨; 柏森; 阳溢; 唐鉴波

    2013-01-01

    On the basis of the study of simultaneous image compression and encryption using number theory,combined with image multiplexing technique , an improved algorithm is proposed. Firstly, four different images with the same size are multiplexed into one image. Then, uses number theory knowledge, the multiplexing image is encrypted and compressed. The simulation experiment results show that the proposed algorithm has a good encryption effect and compression ratio.%在前人应用数论对图像进行同时压缩和加密研究的基础之上,结合图像复用技术,提出了一种改进算法.算法首先将4幅相同尺寸但内容不同的图像利用图像复用技术复合成1幅图像,再对复合的图像应用数论方法进行加密和压缩.仿真实验结果表明,算法具有较好的加密效果和压缩比.

  10. A STRING ENCRYPTION ALGORITHM BASED ON CHAOS THEORY%一种基于混沌理论的字符串加密算法

    陈绍钧

    2011-01-01

    提出一种基于混沌理论的字符串加密算法.通过应用混沌理论的"随机过程"产生随机密钥和随机干扰字符串,使用密钥对明文字符串进行异或(XOR)加密,再将运算后的密文同密钥、干扰字符串按照一定规则组合构成完整的混沌密文.该算法具有运算量小、灵活性强、加密强度高的特点.%The paper presents a string encryption algorithm based on chaos theory. By applying chaos theory' s “random process”, the random key and random interference string are generated. The encryption key encodes plaintext strings with XOR operation; then composes the computed encryption text with the encryption key and interference string together according to designated rules to build a complete chaos encryption text. The algorithm bears such features as fewer calculations, greater flexibilities and stronger encryption.

  11. Secure Image Encryption Based On a Chua Chaotic Noise Generator

    A. S. Andreatos

    2013-10-01

    Full Text Available This paper presents a secure image cryptography telecom system based on a Chua's circuit chaotic noise generator. A chaotic system based on synchronised Master–Slave Chua's circuits has been used as a chaotic true random number generator (CTRNG. Chaotic systems present unpredictable and complex behaviour. This characteristic, together with the dependence on the initial conditions as well as the tolerance of the circuit components, make CTRNGs ideal for cryptography. In the proposed system, the transmitter mixes an input image with chaotic noise produced by a CTRNG. Using thresholding techniques, the chaotic signal is converted to a true random bit sequence. The receiver must be able to reproduce exactly the same chaotic noise in order to subtract it from the received signal. This becomes possible with synchronisation between the two Chua's circuits: through the use of specific techniques, the trajectory of the Slave chaotic system can be bound to that of the Master circuit producing (almost identical behaviour. Additional blocks have been used in order to make the system highly parameterisable and robust against common attacks. The whole system is simulated in Matlab. Simulation results demonstrate satisfactory performance, as well as, robustness against cryptanalysis. The system works with both greyscale and colour jpg images.

  12. Multiple Chaotic Real-time Image Encryption System Based on DSP+FPGA%基于DSP+FPGA的多混沌实时视频图像加密系统

    许艳

    2013-01-01

      Aiming at the security and privacy problems of videos/images in digital communications, a system design scheme for realize real-time videos/images encryption is proposed based on DSP+FPGA, and then the realization of multi-chaotic encryption algorithm based on the DSP+FPGA is introduced in detail. The experimental results show that the encryption algorithm can enhance the security of the videos/images transmission, and it is proved that the system can run with rather fast encryption speed for the real-time videos/images.%  针对视频图像在数字通信中存在着安全和隐私问题,提出了基于DSP+FPGA技术来实现实时视频图像加密的系统设计方案,并详细介绍了多混沌加密算法在DSP和FPGA上的实现。实验结果表明多混沌实时视频图像加密增强了视频图像传输的安全性,同时证明了本系统对实时视频图像能快速地进行加密。

  13. An Integrated Algorithm supporting Confidentiality and Integrity for secured Access and Storage of DICOM Images

    Suresh Jaganathan

    2012-04-01

    Full Text Available In healthcare industry, the patient\\'s medical data plays a vital role because diagnosis of any ailments is done by using those data. The high volume of medical data leads to scalability and maintenance issues when using health-care provider\\'s on-site picture archiving and communication system (PACS and network oriented storage system. Therefore a standard is needed for maintaining the medical data and for better diagnosis. Since the medical data reflects in a similar way to individuals’ personal information, secrecy should be maintained. Maintaining secrecy can be done by encrypting the data, but as medical data involves images and videos, traditional text based encryption/decryption schemes are not adequate for providing confidentiality. In this paper, we propose an algorithm for securing the DICOM format medical archives by providing better confidentiality and maintaining their integrity. Our contribution in this algorithm is of twofold: (1 Development of Improved Chaotic based Arnold Cat Map for encryption/decryption of DICOM files and (2 Applying a new hash algorithm based on chaotic theory for those encrypted files for maintaining integrity. By applying this algorithm, the secrecy of medical data is maintained. The proposed algorithm is tested with various DICOM format image archives by studying the following parameters i PSNR - for quality of images and ii Key - for security.

  14. An image encryption scheme based on the MLNCML system using DNA sequences

    Zhang, Ying-Qian; Wang, Xing-Yuan; Liu, Jia; Chi, Ze-Lin

    2016-07-01

    We propose a new image scheme based on the spatiotemporal chaos of the Mixed Linear-Nonlinear Coupled Map Lattices (MLNCML). This spatiotemporal chaotic system has more cryptographic features in dynamics than the system of Coupled Map Lattices (CML). In the proposed scheme, we employ the strategy of DNA computing and one time pad encryption policy, which can enhance the sensitivity to the plaintext and resist differential attack, brute-force attack, statistical attack and plaintext attack. Simulation results and theoretical analysis indicate that the proposed scheme has superior high security.

  15. Data Hiding and Retrival Using Advanced Encryption and Decryption Algorithms Mamtha Shetty, Shreedhar. A. Joshi

    Mamtha Shetty; Shreedhar. A. Joshi

    2014-01-01

    In this era of digital world, with the evolution of technology, there is an essential need for optimization of online digital data and information. Nowadays, Security and Authenticity of digital data has become a big challenge. This paper proposes an innovative method to authenticate the digital documents. A new method is introduced here, which allows multiple encryption and decryption of digital data.

  16. Encrypted Three-dimensional Dynamic Imaging using Snapshot Time-of-flight Compressed Ultrafast Photography

    Liang, Jinyang; Gao, Liang; Hai, Pengfei; Li, Chiye; Wang, Lihong V.

    2015-10-01

    Compressed ultrafast photography (CUP), a computational imaging technique, is synchronized with short-pulsed laser illumination to enable dynamic three-dimensional (3D) imaging. By leveraging the time-of-flight (ToF) information of pulsed light backscattered by the object, ToF-CUP can reconstruct a volumetric image from a single camera snapshot. In addition, the approach unites the encryption of depth data with the compressed acquisition of 3D data in a single snapshot measurement, thereby allowing efficient and secure data storage and transmission. We demonstrated high-speed 3D videography of moving objects at up to 75 volumes per second. The ToF-CUP camera was applied to track the 3D position of a live comet goldfish. We have also imaged a moving object obscured by a scattering medium.

  17. Encrypted Three-dimensional Dynamic Imaging using Snapshot Time-of-flight Compressed Ultrafast Photography.

    Liang, Jinyang; Gao, Liang; Hai, Pengfei; Li, Chiye; Wang, Lihong V

    2015-01-01

    Compressed ultrafast photography (CUP), a computational imaging technique, is synchronized with short-pulsed laser illumination to enable dynamic three-dimensional (3D) imaging. By leveraging the time-of-flight (ToF) information of pulsed light backscattered by the object, ToF-CUP can reconstruct a volumetric image from a single camera snapshot. In addition, the approach unites the encryption of depth data with the compressed acquisition of 3D data in a single snapshot measurement, thereby allowing efficient and secure data storage and transmission. We demonstrated high-speed 3D videography of moving objects at up to 75 volumes per second. The ToF-CUP camera was applied to track the 3D position of a live comet goldfish. We have also imaged a moving object obscured by a scattering medium. PMID:26503834

  18. Medical Image Protection using steganography by crypto-image as cover Image

    Vinay Pandey; Manish Shrivastava

    2012-01-01

    This paper presents securing the transmission of medical images. The presented algorithms will be applied to images. This work presents a new method that combines image cryptography, data hiding and Steganography technique for denoised and safe image transmission purpose. In This method we encrypt the original image with two shares mechanism encryption algorithm then embed the encrypted image with patient information by using lossless data embedding technique with data hiding method after tha...

  19. An Efficient Image Encryption Scheme Based on a Peter De Jong Chaotic Map and a RC4 Stream Cipher

    Hanchinamani, Gururaj; Kulkarni, Linganagouda

    2015-09-01

    Security is a vital issue in communication and storage of the images and encryption is one of the ways to ensure the security. This paper proposes an efficient image encryption scheme based on a Peter De Jong chaotic map and a RC4 stream cipher. A Peter De Jong map is employed to determine the initial keys for the RC4 stream generator and also during permutation stage. The RC4 stream generator is utilized to generate the pseudo random numbers for the pixel value rotation and diffusion operations. Each encryption round is comprised of three stages: permutation, pixel value rotation and diffusion. The permutation is based on scrambling the rows and columns, in addition, circular rotations of the rows and columns in alternate orientations. The second stage circularly rotates each and every pixel value by utilizing M × N pseudo random numbers. The last stage carries out the diffusion twice by scanning the image in two different ways. Each of the two diffusions accomplishes the diffusion in two orientations (forward and backward) with two previously diffused pixels and two pseudo random numbers. The security and performance of the proposed method is assessed thoroughly by using key space, statistical, differential, entropy and performance analysis. Moreover, two rounds of the call to the encrypt function provide the sufficient security. The experimental results show that the proposed encryption scheme is computationally fast with high security.

  20. Study on the key technology of optical encryption based on compressive ghost imaging with double random-phase encoding

    Zhang, Leihong; Pan, Zilan; Liang, Dong; Ma, Xiuhua; Zhang, Dawei

    2015-12-01

    An optical encryption method based on compressive ghost imaging (CGI) with double random-phase encoding (DRPE), named DRPE-CGI, is proposed. The information is first encrypted by the sender with DRPE, the DRPE-coded image is encrypted by the system of computational ghost imaging with a secret key. The key of N random-phase vectors is generated by the sender and will be shared with the receiver who is the authorized user. The receiver decrypts the DRPE-coded image with the key, with the aid of CGI and a compressive sensing technique, and then reconstructs the original information by the technique of DRPE-decoding. The experiments suggest that cryptanalysts cannot get any useful information about the original image even if they eavesdrop 60% of the key at a given time, so the security of DRPE-CGI is higher than that of the security of conventional ghost imaging. Furthermore, this method can reduce 40% of the information quantity compared with ghost imaging while the qualities of reconstructing the information are the same. It can also improve the quality of the reconstructed plaintext information compared with DRPE-GI with the same sampling times. This technique can be immediately applied to encryption and data storage with the advantages of high security, fast transmission, and high quality of reconstructed information.

  1. A non-linear preprocessing for opto-digital image encryption using multiple-parameter discrete fractional Fourier transform

    Azoug, Seif Eddine; Bouguezel, Saad

    2016-01-01

    In this paper, a novel opto-digital image encryption technique is proposed by introducing a new non-linear preprocessing and using the multiple-parameter discrete fractional Fourier transform (MPDFrFT). The non-linear preprocessing is performed digitally on the input image in the spatial domain using a piecewise linear chaotic map (PLCM) coupled with the bitwise exclusive OR (XOR). The resulting image is multiplied by a random phase mask before applying the MPDFrFT to whiten the image. Then, a chaotic permutation is performed on the output of the MPDFrFT using another PLCM different from the one used in the spatial domain. Finally, another MPDFrFT is applied to obtain the encrypted image. The parameters of the PLCMs together with the multiple fractional orders of the MPDFrFTs constitute the secret key for the proposed cryptosystem. Computer simulation results and security analysis are presented to show the robustness of the proposed opto-digital image encryption technique and the great importance of the new non-linear preprocessing introduced to enhance the security of the cryptosystem and overcome the problem of linearity encountered in the existing permutation-based opto-digital image encryption schemes.

  2. Decryption of pure-position permutation algorithms

    赵晓宇; 陈刚; 张亶; 王肖虹; 董光昌

    2004-01-01

    Pure position permutation image encryption algorithms, commonly used as image encryption investigated in this work are unfortunately frail under known-text attack. In view of the weakness of pure position permutation algorithm,we put forward an effective decryption algorithm for all pure-position permutation algorithms. First, a summary of the pure position permutation image encryption algorithms is given by introducing the concept of ergodic matrices. Then, by using probability theory and algebraic principles, the decryption probability of pure-position permutation algorithms is verified theoretically; and then, by defining the operation system of fuzzy ergodic matrices, we improve a specific decryption al-gorithm. Finally, some simulation results are shown.

  3. QR Code Design of Information Security Based on Rijndael Encryption Algorithm and SHA512 Encryption Algorithm%基于SHA512哈希函数和Rijndael加密算法QR二维码信息安全设计

    肖本海; 郑莹娜; 龙建明; 郭盼盼

    2015-01-01

    随着二维码技术广泛应用于电子票务、银行支票、电子保单等多个领域,二维码的信息泄露和信息篡改等安全问题日益突出。为提高二维码内部信息的安全性能,从对二维码内部信息加密和二维码信息防篡改俩个角度来提高。基于Visual Studio 2008 C#平台,设计了一种采用SHA512哈希函数和Rijndael加密算法混合加密的方法,该方法利用Rijndael加密和SHA512数字签名等技术,对Rijndael第一次加密密钥系统随机分配,并对系统随机分配密钥采用二次Rijndael加密防护方法,并通过SHA512对二维码内部信息防篡改校验,达到对二维码信息及其加密密钥的安全保护。在生成QR二维码之前实现了信息加密,并从系统构架、算法原理和实现及安全性能等多个方面进行了测试和分析。分析表明此方法提高了二维码信息的安全性能,达到对密钥高效管理和对信息的多重保护,而在加密后密文信息容量较明文信息有所增加。%With the QR code technology being widely applied in electronic ticketing, bank checks, E-commerce and other fields, many safety problems have emerged, such as information leakage and data tampering. Based on Visual Studio 2008 c platform, the method with Rijndael random variable and random keys secondary Rijndael encryption protection is proposed using Rijndael encryption and SHA512 digital signature technology. This paper presents a novel design of information security before generating QR code. The encryption principle, algorithm and implementation, safety performance of the proposed method are discussed. Also corresponding testing and analysis are provided to verify the feasibility of the proposed algorithm. Results have proved that the information safety performance of QR code is greatly increased with the encryption algorithm, the efficient management and the multiple- protection to a key. This just causes a smaller increase

  4. Data Hiding and Retrival Using Advanced Encryption and Decryption Algorithms Mamtha Shetty, Shreedhar. A. Joshi

    Mamtha Shetty

    2014-04-01

    Full Text Available In this era of digital world, with the evolution of technology, there is an essential need for optimization of online digital data and information. Nowadays, Security and Authenticity of digital data has become a big challenge. This paper proposes an innovative method to authenticate the digital documents. A new method is introduced here, which allows multiple encryption and decryption of digital data.

  5. Hardware stream cipher with controllable chaos generator for colour image encryption

    Barakat, Mohamed L.

    2014-01-01

    This study presents hardware realisation of chaos-based stream cipher utilised for image encryption applications. A third-order chaotic system with signum non-linearity is implemented and a new post processing technique is proposed to eliminate the bias from the original chaotic sequence. The proposed stream cipher utilises the processed chaotic output to mask and diffuse input pixels through several stages of XORing and bit permutations. The performance of the cipher is tested with several input images and compared with previously reported systems showing superior security and higher hardware efficiency. The system is experimentally verified on XilinxVirtex 4 field programmable gate array (FPGA) achieving small area utilisation and a throughput of 3.62 Gb/s. © The Institution of Engineering and Technology 2013.

  6. A Chaos Robustness Criterion for 2D Piecewise Smooth Map with Applications in Pseudorandom Number Generator and Image Encryption with Avalanche Effect

    Dandan Han

    2016-01-01

    Full Text Available This study proposes a chaos robustness criterion for a kind of 2D piecewise smooth maps (2DPSMs. Using the chaos robustness criterion, one can easily determine the robust chaos parameter regions for some 2DPSMs. Combining 2DPSM with a generalized synchronization (GS theorem, this study introduces a novel 6-dimensional discrete GS chaotic system. Based on the system, a 216-word chaotic pseudorandom number generator (CPRNG is designed. The key space of the CPRNG is larger than 2996. Using the FIPS 140-2 test suit/generalized FIPS 140-2 test suit tests the randomness of the 1000 key streams consists of 20,000 bits generated by the CPRNG, the RC4 algorithm, and the ZUC algorithm, respectively. The numerical results show that the three algorithms do not have significant differences. The CPRNG and a stream encryption scheme with avalanche effect (SESAE are used to encrypt an image. The results demonstrate that the CPRNG is able to generate the avalanche effects which are similar to those generated via ideal CPRNGs. The SESAE with one-time-pad scheme makes any attackers have to use brute attacks to break our cryptographic system.

  7. A Systematic Methodology for Multi-Images Encryption and Decryption Based on Single Chaotic System and FPGA Embedded Implementation

    Hanzhong Zheng

    2014-01-01

    Full Text Available A systematic methodology is developed for multi-images encryption and decryption and field programmable gate array (FPGA embedded implementation by using single discrete time chaotic system. To overcome the traditional limitations that a chaotic system can only encrypt or decrypt one image, this paper initiates a new approach to design n-dimensional (n-D discrete time chaotic controlled systems via some variables anticontrol, which can achieve multipath drive-response synchronization. To that end, the designed n-dimensional discrete time chaotic controlled systems are used for multi-images encryption and decryption. A generalized design principle and the corresponding implementation steps are also given. Based on the FPGA embedded hardware system working platform with XUP Virtex-II type, a chaotic secure communication system for three digital color images encryption and decryption by using a 7D discrete time chaotic system is designed, and the related system design and hardware implementation results are demonstrated, with the related mathematical problems analyzed.

  8. Speckle imaging algorithms for planetary imaging

    Johansson, E. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    I will discuss the speckle imaging algorithms used to process images of the impact sites of the collision of comet Shoemaker-Levy 9 with Jupiter. The algorithms use a phase retrieval process based on the average bispectrum of the speckle image data. High resolution images are produced by estimating the Fourier magnitude and Fourier phase of the image separately, then combining them and inverse transforming to achieve the final result. I will show raw speckle image data and high-resolution image reconstructions from our recent experiment at Lick Observatory.

  9. Binary encoding method to encrypt Fourier-transformed information of digital images

    Lin, Kuang Tsan

    2009-02-01

    An encoding method is used to encrypt the Fourier-transformed information of a hidden (covert) digital image in an overt image, while the Fourier-transformed information must be encoded with binary codes. All of the pixels in an overt image are classified into five groups that are called identification, type, tracing, dimension, and information codes. Identification codes are used to judge if the overt image contains codes that belong to the proposed encoding method or not; type codes are used to judge the encoding type; tracing codes are used to judge the encoding trace; dimension codes are used to judge the size of the hidden information; and information codes are used to decode the hidden information. Applying the proposed encoding method is rather easy, and host images corresponding to overt images are not needed for decoding work. The experiment has demonstrated four types of encoding for the proposed encoding method to reconstruct covert images without any distortion or only with a little distortion.

  10. A Parallel Encryption Algorithm for Block Ciphers Based on Reversible Programmable Cellular Automata

    Das, Debasis; Ray, Abhishek

    2010-01-01

    A Cellular Automata (CA) is a computing model of complex System using simple rule. In CA the problem space into number of cell and each cell can be one or several final state. Cells are affected by neighbours' to the simple rule. Cellular Automata are highly parallel and discrete dynamical systems, whose behaviour is completely specified in terms of a local relation. This paper deals with the Cellular Automata (CA) in cryptography for a class of Block Ciphers through a new block encryption al...

  11. Testing a Variety of Encryption Technologies

    Henson, T J

    2001-04-09

    Review and test speeds of various encryption technologies using Entrust Software. Multiple encryption algorithms are included in the product. Algorithms tested were IDEA, CAST, DES, and RC2. Test consisted of taking a 7.7 MB Word document file which included complex graphics and timing encryption, decryption and signing. Encryption is discussed in the GIAC Kickstart section: Information Security: The Big Picture--Part VI.

  12. Simple Encryption/Decryption Application

    Majdi Al-qdah

    2007-06-01

    Full Text Available This paper presents an Encryption/Decryption application that is able to work with any type of file; for example: image files, data files, documentation files…etc. The method of encryption is simple enough yet powerful enough to fit the needs of students and staff in a small institution. The application uses simple key generation method of random number generation and combination. The final encryption is a binary one performed through rotation of bits and XOR operation applied on each block of data in any file using a symmetric decimal key. The key generation and Encryption are all done by the system itself after clicking the encryption button with transparency to the user. The same encryption key is also used to decrypt the encrypted binary file.

  13. Investigating Encrypted Material

    McGrath, Niall; Gladyshev, Pavel; Kechadi, Tahar; Carthy, Joe

    When encrypted material is discovered during a digital investigation and the investigator cannot decrypt the material then s/he is faced with the problem of how to determine the evidential value of the material. This research is proposing a methodology of extracting probative value from the encrypted file of a hybrid cryptosystem. The methodology also incorporates a technique for locating the original plaintext file. Since child pornography (KP) images and terrorist related information (TI) are transmitted in encrypted format the digital investigator must ask the question Cui Bono? - who benefits or who is the recipient? By doing this the scope of the digital investigation can be extended to reveal the intended recipient.

  14. Spread spectrum image data hiding in the encrypted discrete cosine transform coefficients

    Zhang, Xiaoqiang; Wang, Z. Jane

    2013-10-01

    Digital watermarking and data hiding are important tools for digital rights protection of media data. Spread spectrum (SS)-based watermarking and data-hiding approaches are popular due to their outstanding robustness, but their security might not be sufficient. To improve the security of SS, a SS-based image data-hiding approach is proposed by encrypting the discrete cosine transform coefficients of the host image with the piecewise linear chaotic map, before the operation of watermark embedding. To evaluate the performance of the proposed approach, simulations and analyses of its robustness and security are carried out. The average bit-error-rate values on 100 real images from the Berkeley segmentation dataset under the JPEG compression, additive Gaussian noise, salt and pepper noise, and cropping attacks are reported. Experimental results show that the proposed approach can maintain the high robustness of traditional SS schemes and, meanwhile, also improve the security. The proposed approach can extend the key space of traditional SS schemes from 10 to 10 and thus can resist brute-force attack and unauthorized detection watermark attack.

  15. Modified Trial Division Algorithm Using KNJ-Factorization Method To Factorize RSA Public Key Encryption

    Lal, Nidhi; Singh, Anurag Prakash; Kumar, Shishupal

    2015-01-01

    The security of RSA algorithm depends upon the positive integer N, which is the multiple of two precise large prime numbers. Factorization of such great numbers is a problematic process. There are many algorithms has been implemented in the past years. The offered KNJ -Factorization algorithm contributes a deterministic way to factorize RSA. The algorithm limits the search by only considering the prime values. Subsequently prime numbers are odd numbers accordingly it also requires smaller num...

  16. 图像加密域可分离可逆信息隐藏算法的系统设计与实现%Design and implementation of system for separable reversible data hiding in encrypted image

    乔中良

    2015-01-01

    改进了一种图像加密域可分离可逆信息隐藏的算法,设计并实现了一个图像加密域的可分离可逆信息隐藏软件系统。在此系统中,内容拥有者对未压缩的原始图像使用加密密钥进行加密。然后,信息隐藏者使用信息隐藏密钥把加密图像的最低位平面进行压缩,在压缩所得的空余空间里嵌入额外数据。最后得到包含嵌入信息的加密图像:拥有信息隐藏密钥的接收方,尽管不知道原始图片内容也可以提取出隐藏信息;拥有加密密钥的接收方可以获得原始图像的近似图,但是不能提取隐藏信息;如果同时拥有加密密钥和信息隐藏密钥,那么既可以提取出隐藏信息,也可以利用自然图像的空间相关性恢复出图像的相似图像。实例测试的结果表明,算法具有嵌入容量大、操作更灵活的优点。%An algorithm of separable reversible information hiding in encrypted image was improved. A system of separable reversible information hiding in encrypted image was designed and implemented. In the system, a content owner encrypts the original image with an encryption key. An information hider compresses the lowest bit plane of the encrypted image with an information hiding key in order to create a spare space. The additional data is embedded in the spare space. Finally the encrypted image with the embedded information is produced. For the recipient with information hiding key, he can extract the hiding information, but he could not know the original image. For the recipient with the encryption key, he can decrypt the encrypted data directly to obtain an image similar to the original one, but he could not extract the embedding data. For the recipient with information hiding key and the encryption key, he not only can extract the additional data, but also can recover the similar version of the original image by using the spatial correlation of natural image. The results of

  17. Design and Implementation of Encryption Algorithm for Aquatic Products Traceability Code%水产品追溯码加密算法设计与应用

    李文勇; 孙传恒; 刘学馨; 周超; 谢菁; 杨信廷

    2012-01-01

    为解决当前农产品追溯码安全性不高,难以保证一品一码等问题,以水产品为研究对象,提出了一种水产品追溯码加密算法.在深入分析各种追溯码编码方案和AES加密算法的基础上,对水产品监管码进行编码、压缩和十进制等长加密生成水产品追溯码.实验证明算法可行、可靠;密钥的动态变化和追溯码的唯一性,为追溯系统的实际应用提供了安全保障.最后给出了该算法在水产品质量追溯系统中的应用方案.%In order to solve such problems as low-level security of traceability code for agricultural products and difficulty to guarantee the traceability code was unique for one product, taking aquatic products as research object, an encryption algorithm of traceability code for aquatic products was put forward. At the base of analysis to coding solution of traceability code and AES encryption algorithm, the aquatic product was coded. Then, this supervision code was compressed and encrypted by an algorithm namely decimal and equal-length to generate the traceability code for aquatic products. The experimental results showed that the proposed algorithm was feasible and reliable. It ensured the deployment security of traceability system owing to the feature of uniqueness and dynamic cipher of traceability code. An example of the application solution of the encryption algorithm in aquatic products traceability system was introduced.

  18. Optical Encryption with Jigsaw Transform using Matlab

    Giraldo, Leidy Marcela

    2012-01-01

    This article will describe an optical encryption technical of images which it is proposed in an analogical and digital way. The development of the technical to a digital level, it is made to implementing algorithms (routines) in MATLAB. We will propose a functional diagram to the described analogical development from which designated the optical systems associated with each functional block. Level of security that the jigsaw algorithms provide applied on an image, which has been decomposed into its bit-planes, is significantly better if they are applied on an image that has not been previously decomposed.

  19. Thermal image encryption obtained with a SiO2 space-variant subwavelength grating supporting surface phonon-polaritons.

    Dahan, Nir; Niv, Avi; Biener, Gabriel; Kleiner, Vladimir; Hasman, Erez

    2005-12-01

    Space-variant partially polarized thermal emission is investigated. We show that by coupling surface phonon-polaritons to a propagating field, large anisotropy of the emissivity is obtained within a narrow spectral range. We experimentally demonstrate this effect by fabricating a space-variant subwavelength grating on a SiO2 substrate to encrypt an image in the polarization state of a thermal radiation field. PMID:16342718

  20. A Space-bit-plane Scrambling Algorithm for Image Based on Chaos

    Rui Liu

    2011-10-01

    Full Text Available Image scrambling is an important technique in digital image encryption and digital image watermarking. This paper's main purpose is to research how to scramble image by space-bit-plane operation (SBPO. Based on analyzing traditional bit operation of individual pixels image scrambling method, this paper proposed a new scrambling algorithm. The new scrambling algorithm combined with SBPO and chaotic sequence. First, every eight pixels from different areas of image were selected according to chaotic sequence, and grouped together to form a collection. Second, the SBPO was performed in every collection and built eight pixels of the image with new values. The scrambling image was generated when all pixels were processed. In this way, the proposed algorithm transforms drastically the statistical characteristic of original image information, so, it increases the difficulty of an unauthorized individual to break the encryption. The simulation results and the performance analysis show that the algorithm has large secret-key space, high security, fast scrambling speed and strong robustness, and is suitable for practical use to protect the security of digital image information over the Internet.

  1. A Novel Steganographic Scheme Based on Hash Function Coupled With AES Encryption

    Rinu Tresa M J

    2014-04-01

    Full Text Available In the present scenario the use of images increased extremely in the cyber world so that we can easily transfer data with the help of these images in a secured way. Image steganography becomes important in this manner. Steganography and cryptography are the two techniques that are often confused with each other. The input and output of steganogra phy looks alike, but for cryptography the output will be in an encrypted form which always draws attraction to the attacker. This paper combines both steganography and cryptography so that attacker doesn’t know about the existence of message and the message itself is encrypted to ensure more security. The textual data entered by the user is encrypted using AES algorithm. After encryption, the encrypted data is stored in the colour image by using a hash based algorithm. Most of the steganographic algorithms available today is suitable for a specific image format and these algorithms suffers from poor quality of the embedded image. The proposed work does not corrupt the images quality in any form. The striking feature is that this algorithm is suitable for almost all image formats e.g.: jpeg/jpg, Bitmap, TIFF and GIF

  2. 基于MD5与Base64的混合加密算法%MD5-Base64 based hybrid encryption algorithm

    罗江华

    2012-01-01

    介绍了一种基于MD5和Base64的混合加密算法,首先将明文MD5加密得到32位16进制密文,再将32位密文拆分成16个2位16进制数组,并转换成对应的二进制数,最后将16个二进制数组连接成一个128位的2进制数,采用Base64加密原理进行加密.该算法可以避免查询MD5散列值字典获取用户明文密码,更加有效地保证了用户的密码安全,最后给出了算法的PHP实现.%A MD5-Base64 baaed hybrid encryption algorithm was introduced, which encrypted plain text to 32-bit hexadecimal cipher text by MDS encryption, then split this 32-bit hexadecimal into 16 parts, and transformed them into binary Cor each part to join them together as a 128-bit binary, finally, encrypted the 128-bit binary array by using Base64 algorithm. This algorithm can avoid getting user's clear text password by querying MDS hash database, and protect user's password more effectively. This algorithm was described by PHP script language at the fourth section.

  3. All-Optical video-image encryption enforced security level using ICA

    Alfalou, Ayman; Mansour, Ali

    2007-01-01

    In the last two decades, wireless communications have been introduced in various applications. However, the transmitted data can be, at any moment, intercepted by non-authorized person. That could be explain why data encryption and secure transmission have gained enormous popularity. In order to secure data transmission, one should pay attention to two problems: transmission rate and encryption security level. In this manuscript, we address the last two problems by proposing a new videoimage ...

  4. Advanced Imaging Algorithms for Radiation Imaging Systems

    Marleau, Peter [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-10-01

    The intent of the proposed work, in collaboration with University of Michigan, is to develop the algorithms that will bring the analysis from qualitative images to quantitative attributes of objects containing SNM. The first step to achieving this is to develop an indepth understanding of the intrinsic errors associated with the deconvolution and MLEM algorithms. A significant new effort will be undertaken to relate the image data to a posited three-dimensional model of geometric primitives that can be adjusted to get the best fit. In this way, parameters of the model such as sizes, shapes, and masses can be extracted for both radioactive and non-radioactive materials. This model-based algorithm will need the integrated response of a hypothesized configuration of material to be calculated many times. As such, both the MLEM and the model-based algorithm require significant increases in calculation speed in order to converge to solutions in practical amounts of time.

  5. Using a Grid to Evaluate the Threat of Zombie Networks against Asymmetric Encryption Algorithms

    The large network of compromised computers currently available can be used to run complex algorithms in order to solve problems considered to be beyond current computational power. A distribute algorithm for obtaining prime number is presented. The algorithm was run in a grid system to obtain all prime numbers up to 240, measuring execution times and storage requirements. Extrapolating the results to larger limits it was found that using zombie networks it is possible to obtain prime number up to a limit of 250. The main conclusion is that using this technique, low transfer rates and storage capabilities are the current limiting factors, surpassing the limited computing power. (Author)

  6. Using a Grid to Evaluate the Threat of Zombie Networks against Asymmetric Encryption Algorithms

    Palacios, R.

    2007-07-01

    The large network of compromised computers currently available can be used to run complex algorithms in order to solve problems considered to be beyond current computational power. A distribute algorithm for obtaining prime number is presented. The algorithm was run in a grid system to obtain all prime numbers up to 240, measuring execution times and storage requirements. Extrapolating the results to larger limits it was found that using zombie networks it is possible to obtain prime number up to a limit of 250. The main conclusion is that using this technique, low transfer rates and storage capabilities are the current limiting factors, surpassing the limited computing power. (Author)

  7. A novel chaotic encryption scheme based on pseudorandom bit padding

    Sadra, Yaser; Fard, Zahra Arasteh

    2012-01-01

    Cryptography is always very important in data origin authentications, entity authentication, data integrity and confidentiality. In recent years, a variety of chaotic cryptographic schemes have been proposed. These schemes has typical structure which performed the permutation and the diffusion stages, alternatively. The random number generators are intransitive in cryptographic schemes and be used in the diffusion functions of the image encryption for diffused pixels of plain image. In this paper, we propose a chaotic encryption scheme based on pseudorandom bit padding that the bits be generated by a novel logistic pseudorandom image algorithm. To evaluate the security of the cipher image of this scheme, the key space analysis, the correlation of two adjacent pixels and differential attack were performed. This scheme tries to improve the problem of failure of encryption such as small key space and level of security.

  8. A novel chaotic encryption scheme based on pseudorandom bit padding

    Sodeif Ahadpour

    2012-01-01

    Full Text Available Cryptography is always very important in data origin authentications, entity authentication, data integrity and confidentiality. In recent years, a variety of chaotic cryptographic schemes have been proposed. These schemes has typical structure which performed the permutation and the diffusion stages, alternatively. The random number generators are intransitive in cryptographic schemes and be used in the diffusion functions of the image encryption for diffused pixels of plain image. In this paper, we propose a chaotic encryption scheme based on pseudorandom bit padding that the bits be generated by a novel logistic pseudorandom image algorithm. To evaluate the security of the cipher image of this scheme, the key space analysis, the correlation of two adjacent pixels and differential attack were performed. This scheme tries to improve the problem of failure of encryption such as small key space and level of security.

  9. An Integrated Algorithm Supporting Confidentiality and Integrity for Secured Access and Storage of DICOM Images

    Suresh Jaganathan

    2012-04-01

    Full Text Available In healthcare industry, the patient's medical data plays a vital role because diagnosis of anyailments is done by using those data. The high volume of medical data leads to scalability andmaintenance issues when using health-care provider's on-site picture archiving andcommunication system (PACS and network oriented storage system. Therefore a standard isneeded for maintaining the medical data and for better diagnosis. Since the medical data reflectsin a similar way to individuals’ personal information, secrecy should be maintained. Maintainingsecrecy can be done by encrypting the data, but as medical data involves images and videos,traditional text based encryption/decryption schemes are not adequate for providingconfidentiality. In this paper, we propose an algorithm for securing the DICOM format medicalarchives by providing better confidentiality and maintaining their integrity. Our contribution in thisalgorithm is of twofold: (1 Development of Improved Chaotic based Arnold Cat Map forencryption/decryption of DICOM files and (2 Applying a new hash algorithm based on chaotictheory for those encrypted files for maintaining integrity. By applying this algorithm, the secrecy ofmedical data is maintained. The proposed algorithm is tested with various DICOM format imagearchives by studying the following parameters i PSNR - for quality of images and ii Key - forsecurity.

  10. A comparative study of several lightweight encryption algorithms%几种轻量级加密算法的比较研究

    路安平; 杨济民; 李锋; 张宝译; 陈冲

    2014-01-01

    With the rapid development of radio frequency identification(RFID)technology,the lightweight encryption algo-rithm attracts increasing attention. In RFID system,the hardware resources are extremely limited. In order to get a better trade-off between the algorithm's encryption performance and the hardware resource requirements,the elliptic curve cryptography (ECC)is compared with RC4 algorithm in the stream cipher algorithm and PRESENT algorithm in the grouping encryption algo-rithm. Through the Atmega-32 microprocessor in the AVR Studio simulation platform,the comparison results between the three algorithms′ efficiency and the hardware requirements are obtained. The ECC algorithm ,under the condition of the same restricted hardware resources,is better in the operation efficiency and the password security than the other two algorithms. It proves that the non-symmetric encryption algorithm can also be lightweight.%随着无线射频识别(RFID)技术在各个应用领域的迅猛发展,轻量级(lightweight)加密算法日益受到人们的关注。在RFID中硬件资源是极端受限制的,为了在算法加密性能与硬件资源开销间得到一个好的权衡,把椭圆曲线加密算法(ECC)与流密码加密算法中RC4算法,分组加密算法中的PRESENT算法,进行分析比较。并选取Atmega-32微处理器在AVR Studio仿真平台上进行分析比较。实验获得了这三种算法在算法运行效率、密码安全强度和硬件资源开销间的比较结果。得出,在硬件资源同样极端受限的环境下,ECC所表现出的运行效率和密码安全强度是其他两种算法所不能比拟的,证明了非对称加密算法也可以做到轻量化。

  11. Edge-based lightweight image encryption using chaos-based reversible hidden transform and multiple-order discrete fractional cosine transform

    Zhang, Yushu; Xiao, Di; Wen, Wenying; Tian, Yuan

    2013-12-01

    In some special multimedia applications, only the regions with semantic information should be provided better protection whereas the other smooth regions can be free of encryption. However, most of the existing multimedia security schemes only consider bits and pixels rather than semantic information during their encryption. Motivated by this, we propose an edge-based lightweight image encryption scheme using chaos-based reversible hidden transform and multiple-order discrete fractional cosine transform. An image is first carried out by the edge detection based on advanced CNN structure with adaptive thresholds to assess data significance in the image. The detection output is a binary image, in which a “1” reflects the detected pixel whereas a “0” is opposite. Both the detected image and the original image are divided into non-overlapping pixel blocks in the same way, respectively. Whether each block is encrypted or not depends on the significance judged by the corresponding detected block. The significant block is performed by reversible hidden transform followed by multiple-order discrete fractional cosine transform parameters and orders of these two transforms are determined by a two dimensional cross chaotic map. Experiment results show the significant contour features of an image that have been largely hidden only by encrypting about half pixels in the average sense. The keys are extremely sensitive and the proposed scheme can resist noise attack to some extent.

  12. An image processing algorithm for PPCR imaging

    Cowen, Arnold R.; Giles, Anthony; Davies, Andrew G.; Workman, A.

    1993-09-01

    During 1990 The UK Department of Health installed two Photostimulable Phosphor Computed Radiography (PPCR) systems in the General Infirmary at Leeds with a view to evaluating the clinical and physical performance of the technology prior to its introduction into the NHS. An issue that came to light from the outset of the projects was the radiologists reservations about the influence of the standard PPCR computerized image processing on image quality and diagnostic performance. An investigation was set up by FAXIL to develop an algorithm to produce single format high quality PPCR images that would be easy to implement and allay the concerns of radiologists.

  13. Experimental opto-digital synthesis of encrypted sub-samples of an image to improve its decoded quality

    Barrera, John Fredy; Rueda, Edgar; Rios, Carlos; Tebaldi, Myrian; Bolognini, Néstor; Torroba, Roberto

    2011-09-01

    We develop an experimental protocol to visualize decrypted images that otherwise would have been barely recognizable, while keeping the standard security levels. This image deterioration is partly due to the natural speckle noise as well as the practical limitations arising from the optical elements composing the setup. This protocol is based on an optical image synthesis with digital holography using enlarged sub-samples of an entire image together with a multiplexing technique. We implement the process using a Mach-Zehnder interferometer with a joint transform correlator encrypting architecture. As a result, we get smaller speckle patterns on the final assembled image and a spatial frequency enhancement with respect to the decoded image obtained with the conventional procedures.

  14. SRI RAMSHALAKA: A VEDIC METHOD OF TEXT ENCRYPTION AND DECRYPTION

    Rajkishore Prasad

    2013-07-01

    Full Text Available This paper investigates usability of SriRamshalakha, a vedic tool used in Indian Astrology, in the encryption and decryption of plain English text. Sri Ram Shalaka appears in Sri RamChartmanas, one of the very popular sacred epic of Hindu religion, written by great Saint Tulsidasji. SriRamshalakha is used to fetch/infer the approximate answer of questions/decisions by the believers. Basically, the said shalaka embed nine philosophical verses from Sri RamCharitmanas in a matrix form based on which answers to queries are inferred and ingrained. However, none of the verses are visible and directly readable. Thus here we take SriRamshalakha as the ancient Indian method of text encryption and decryption and based on the same algorithms for the encryption and decryption of plain English text areproposed. The developed algorithms are presented with examples and possibility of its use in steganography and text to image transformation are also discussed.

  15. Cancelable face verification using optical encryption and authentication.

    Taheri, Motahareh; Mozaffari, Saeed; Keshavarzi, Parviz

    2015-10-01

    In a cancelable biometric system, each instance of enrollment is distorted by a transform function, and the output should not be retransformed to the original data. This paper presents a new cancelable face verification system in the encrypted domain. Encrypted facial images are generated by a double random phase encoding (DRPE) algorithm using two keys (RPM1 and RPM2). To make the system noninvertible, a photon counting (PC) method is utilized, which requires a photon distribution mask for information reduction. Verification of sparse images that are not recognizable by direct visual inspection is performed by unconstrained minimum average correlation energy filter. In the proposed method, encryption keys (RPM1, RPM2, and PDM) are used in the sender side, and the receiver needs only encrypted images and correlation filters. In this manner, the system preserves privacy if correlation filters are obtained by an adversary. Performance of PC-DRPE verification system is evaluated under illumination variation, pose changes, and facial expression. Experimental results show that utilizing encrypted images not only increases security concerns but also enhances verification performance. This improvement can be attributed to the fact that, in the proposed system, the face verification problem is converted to key verification tasks. PMID:26479930

  16. Image reconstruction algorithms from projections

    Many physical or bio-physical phenomena can be analysed as 'images' that is to say a bi-dimensionnal representation of a characteristic parameter of the material (density, concentration of a given element, resistivity, etc...). The various algorithms reviewed in the paper lead to a numerical reconstitution of such an image from a finite set of measurements considered as 'projections' of the initial object. We first give a physical insight then the mathematical formulation of the various concepts necessary for the presentation of the problem; after that we show why and how many reconstruction algorithms are possible. These different strategies are quickly compared chiefly according to realization facilities, structure, volume and performances (speed, accuracy) of the processing system required

  17. Enhanced Throughput AES Encryption

    Kunal Lala; Ajay Kumar; De, Amit Kumar

    2012-01-01

    This paper presents our experience in implementing the Advanced Encryption Standard (AES) algorithm. We have used 128 bit block size and 128 bit cipher key for the implementation. The AES also known as Rijndael algorithm is used to ensure security of transmission channels. Xilinx design tool 13.3 and Xilinx project navigator design tool are used for synthesis and simulation. Very high speed integrated circuit hardware description language (VHDL) is used for coding. The fully pipelined desig...

  18. FPGA Implementation of Secure Force (64-Bit Low Complexity Encryption Algorithm

    Shujaat Khan

    2015-11-01

    Full Text Available Field-Programmable Gate Arrays (FPGAs have turned out to be a well-liked target for implementing cryptographic block ciphers, a well-designed FPGA solution can combine some of the algorithmic flexibility and cost efficiency of an equivalent software implementation with throughputs that are comparable to custom ASIC designs. The recently proposed Secure Force (SF shows good results in terms of resource utilization compared to older ciphers. SF appears as a promising choice for power and resource constrained secure systems and is well suited to an FPGA implementation. In this paper we explore the design decisions that lead to area/delay tradeoffs in a full loop-unroll implementation of SF-64 on FPGA. This work provides hardware characteristics of SF along with implementation results that are optimal in terms of throughput, latency, power utilization and area efficiency.

  19. Image feature extraction in encrypted domain with privacy-preserving SIFT.

    Hsu, Chao-Yung; Lu, Chun-Shien; Pei, Soo-Chang

    2012-11-01

    Privacy has received considerable attention but is still largely ignored in the multimedia community. Consider a cloud computing scenario where the server is resource-abundant, and is capable of finishing the designated tasks. It is envisioned that secure media applications with privacy preservation will be treated seriously. In view of the fact that scale-invariant feature transform (SIFT) has been widely adopted in various fields, this paper is the first to target the importance of privacy-preserving SIFT (PPSIFT) and to address the problem of secure SIFT feature extraction and representation in the encrypted domain. As all of the operations in SIFT must be moved to the encrypted domain, we propose a privacy-preserving realization of the SIFT method based on homomorphic encryption. We show through the security analysis based on the discrete logarithm problem and RSA that PPSIFT is secure against ciphertext only attack and known plaintext attack. Experimental results obtained from different case studies demonstrate that the proposed homomorphic encryption-based privacy-preserving SIFT performs comparably to the original SIFT and that our method is useful in SIFT-based privacy-preserving applications. PMID:22711774

  20. Multiple image encryption based on Fourier transform holography under spherical wave illumination%球面波照明下傅里叶变换全息多图像加密方法研究

    沈学举; 刘旭敏; 许芹祖; 林超

    2014-01-01

    To reduce the number of binary random phase mask used in an image encryption system and simplify the effect of hidden encryption images on decryption process , an optical multiple-image encryption and hiding scheme was put forward based on Fourier transform holography under spherical wave illumination .Theoretical analysis and numerical simulation of image encryption and hiding encryption image and image decryption were made .The results show that correlation coefficient between encryption image and original image approaches 0, correlation coefficient between host image and hiding encryption image approaches 1 when superposition coefficient ρbetween host image and hiding encryption image is less than 0.3, correlation coefficient between decryption image and original image approaches 1.The encryption method can obtain good encryption effect .%为了减少加密系统所用模板数,简化隐藏图像对解密过程的影响,采用球面波照明研究了基于傅里叶变换全息的多图像加密隐藏方法,并进行了加密、加密图像隐藏和解密的理论分析和数值模拟,加密图像和原始图像间的相关系数趋于0,宿主图像和加密图像的叠加系数ρ<0.3时,宿主图像和隐藏图像的相关系数趋于1,解密图像和原始图像间的相关系数趋于1。结果表明,该加密隐藏方法的加密、解密和隐藏效果良好。

  1. Spaceborne SAR Imaging Algorithm for Coherence Optimized.

    Zhiwei Qiu

    Full Text Available This paper proposes SAR imaging algorithm with largest coherence based on the existing SAR imaging algorithm. The basic idea of SAR imaging algorithm in imaging processing is that output signal can have maximum signal-to-noise ratio (SNR by using the optimal imaging parameters. Traditional imaging algorithm can acquire the best focusing effect, but would bring the decoherence phenomenon in subsequent interference process. Algorithm proposed in this paper is that SAR echo adopts consistent imaging parameters in focusing processing. Although the SNR of the output signal is reduced slightly, their coherence is ensured greatly, and finally the interferogram with high quality is obtained. In this paper, two scenes of Envisat ASAR data in Zhangbei are employed to conduct experiment for this algorithm. Compared with the interferogram from the traditional algorithm, the results show that this algorithm is more suitable for SAR interferometry (InSAR research and application.

  2. The Mainstream Image Encryption Technology and Its New Progress%主流图像加密技术及其新进展

    李琼; 梁冬梅; 鲁菁

    2013-01-01

    With the development of network technology, communications privacy and information security technology is more and more popular. This article reviews the variety of image encryption technology principle, characteristics and development, pointed out the development direction of digital image encryption technology.%随着网络技术的发展,通信隐私和信息安全技术越来越受重视.本文综述了多种图像加密技术的原理、特点和进展,指出了数字图像加密技术的发展方向.

  3. Hardware Implementation of Multimedia Encryption Techniques Using FPGA

    M. A. Mohamed; M.E. Abou-Elsoud; W.M. Kamal El-Din

    2012-01-01

    Multimedia encryption algorithm has gain importance nowadays for copyright protection. Many multimedia encryption Techniques had been designed and tested software base. We will implement a library of hardware realization using FPGA of seven multimedia encryption algorithms. Simulation results had shown that blowfish provided the best result. In addition we proposed new encryption method based on cascaded techniques. This cascaded method provides a great improvement .The discussed techniques w...

  4. 一种基于 me mo ry 的数据加解密算法%An Encryption and Decryption Algorithm of Data Based on Memory

    张金旻; 谢小东

    2015-01-01

    Most memory researches only focus on improving the performance ,which is to enlarge the capacityand and to increase the speed .However ,aided designs to realize more functions have been rarely achieved in present memory studies .So an algorithm to encrypt and decrypt the address of memory is given out in this paper ,and the encryption and decryption of the data is realized ,which is based on the characteristics of memory ,and the feasibility of this algorithm with simulation is validates .%对于memory的研究,大部分都只是停留在对容量的扩充,速度的提高等性能提升方面,很少涉及对mem‐ory进行辅助设计以实现更多的特殊功能。提出了一种通过对memory地址作用加解密算法,利用memory自身的特性来实现对数据的加解密的功能,并通过实验仿真验证了该方法的可行性。

  5. ROBUST SECURE AND BLIND WATERMARKING BASED ON DWT DCT PARTIAL MULTI MAP CHAOTIC ENCRYPTION

    Esam A. Hagras

    2011-11-01

    Full Text Available In this paper, a novel Commutative Watermarking and Partial Encryption (CWPE algorithm based on Discrete Wavelet Transform and Discrete Cosine Transform (DWT-DCT for watermarking and Multi-Map Wavelet Chaotic Encryption (MMW-CE is proposed. The original host image is first decomposed into four sub-bands using (DWT, each sub-band coefficients are relocated using Arnold transform to create a noiselike version, then apply partial encryption scheme using chaotic scrambled random number pattern bitwise XOR with the scrambled horizontal coefficients only and the shuffled approximation coefficients are divided into non-overlapping and equal sized blocks. Watermark embedding process is based on extracting the (DCT middle frequencies of the encrypted approximation coefficients blocks. Comparison based threshold of the extracted DCT mid-band coefficients, watermark bits are embedded in the coefficients of the corresponding DCT middle frequencies. The experimental results show that the proposed algorithm is robust against common signal processing attacks. The proposed algorithm is able to reduce encryption to one quarter of the image information. Statistical and differential analyses are performed to estimate the security strength of the proposed algorithm. The results of the security analysis show that the proposed algorithm provides a high security level for real time application.

  6. Recent advances in optical encryption techniques

    YAN Aimin; HU Zhijuan; POON Tingchung

    2015-01-01

    Optical techniques have shown great potential in information security.This paper reviews the most recent technological and application advances of optical encryption of 2-D and 3-D objects.The main optical encryption techniques and encryption algorithms are summarized and illustrated in detail.Challenges and developments,which are the subject of the contributions to this focus paper,are also discussed,and prospects are predicted.

  7. Encryption using Deterministic Chaos

    Blackledge, Jonathan; Ptitsyn, Nikolai

    2010-01-01

    The concepts of randomness, unpredictability, complexity and entropy form the basis of modern cryptography and a cryptosystem can be interpreted as the design of a key-dependent bijective transformation that is unpredictable to an observer for a given computational resource. For any cryptosystem, including a Pseudo-Random Number Generator (PRNG), encryption algorithm or a key exchange scheme, for example, a cryptanalyst has access to the time series of a dynamic system and knows the PRNG func...

  8. Medical Image Protection using steganography by crypto-image as cover Image

    Vinay Pandey

    2012-09-01

    Full Text Available This paper presents securing the transmission of medical images. The presented algorithms will be applied to images. This work presents a new method that combines image cryptography, data hiding and Steganography technique for denoised and safe image transmission purpose. In This method we encrypt the original image with two shares mechanism encryption algorithm then embed the encrypted image with patient information by using lossless data embedding technique with data hiding method after that for more security. We apply steganography by encrypted image of any other medical image as cover image and embedded images as secrete image with the private key. In receiver side when the message is arrived then we apply the inverse methods in reverse order to get the original image and patient information and to remove noise we extract the image before the decryption of message. We have applied and showed the results of our method to medical images.

  9. 基于FTP的图像混沌加密传输技术的实现%Implementation of transmitting chaotic-encrypted image based on FTP

    刘新杰; 李黎明

    2014-01-01

    In order to accelerate the rate of chaotic-encrypted image transmission system and extend its field of application , this paper proposes a new method of transmitting chaotic-encrypted image: applying VSFTPD software to Mini 2440 ARM platform to setup a FTP server , and using FTP to convey the encrypted image files . The experiment result shows that this system can trans-fer chaotic-encrypted images rapidly and reliably .%为了提高混沌图像加密传输系统的传输速度并扩大应用范围,提出了一种实现混沌图像加密传输的新方法:利用 VSFTPD 软件在 Mini 2440 ARM 平台上构建 FTP 服务器,通过 FTP 实现混沌加密图像数据的传输。实验结果表明,该系统能够实现混沌加密图像的可靠快速传输。

  10. Simple Encryption/Decryption Application

    Majdi Al-qdah; Lin Yi Hui

    2007-01-01

    This paper presents an Encryption/Decryption application that is able to work with any type of file; for example: image files, data files, documentation files…etc. The method of encryption is simple enough yet powerful enough to fit the needs of students and staff in a small institution. The application uses simple key generation method of random number generation and combination. The final encryption is a binary one performed through rotation of bits and XOR operation applied on each b...

  11. Optical image encryption using equal modulus decomposition and multiple diffractive imaging

    Fatima, Areeba; Mehra, Isha; Nishchal, Naveen K.

    2016-08-01

    The equal modulus decomposition (EMD) is a novel asymmetric cryptosystem based on coherent superposition which was proposed to resist the specific attack. In a subsequent work, the scheme was shown to be vulnerable to specific attack. In this paper, we counter the vulnerability through an encoding technique which uses multiple diffraction intensity pattern recordings as the input to the EMD setup in the gyrator domain. This allows suppression of the random phase mask in the EMD path. As a result, the proposed scheme achieves resistance to specific attack. The simulation results and the security analysis demonstrate that EMD based on multiple intensity pattern recording is an effective optical asymmetric cryptosystem suitable for securing data and images.

  12. ENAS-RIF algorithm for image restoration

    Yang, Yang; Yang, Zhen-wen; Shen, Tian-shuang; Chen, Bo

    2012-11-01

    mage of objects is inevitably encountered by space-based working in the atmospheric turbulence environment, such as those used in astronomy, remote sensing and so on. The observed images are seriously blurred. The restoration is required for reconstruction turbulence degraded images. In order to enhance the performance of image restoration, a novel enhanced nonnegativity and support constants recursive inverse filtering(ENAS-RIF) algorithm was presented, which was based on the reliable support region and enhanced cost function. Firstly, the Curvelet denoising algorithm was used to weaken image noise. Secondly, the reliable object support region estimation was used to accelerate the algorithm convergence. Then, the average gray was set as the gray of image background pixel. Finally, an object construction limit and the logarithm function were add to enhance algorithm stability. The experimental results prove that the convergence speed of the novel ENAS-RIF algorithm is faster than that of NAS-RIF algorithm and it is better in image restoration.

  13. Robust Secure and Blind Watermarking Based on DWT DCT Partial Multi Map Chaotic Encryption

    Esam A. Hagras

    2011-12-01

    Full Text Available In this paper, a novel Commutative Watermarking and Partial Encryption (CWPE algorithm based onDiscrete Wavelet Transform and Discrete Cosine Transform (DWT-DCT for watermarking and Multi-MapWavelet Chaotic Encryption (MMW-CE is proposed. The original host image is first decomposed into foursub-bands using (DWT, each sub-band coefficients are relocated using Arnold transform to create a noiselikeversion, then apply partial encryption scheme using chaotic scrambled random number pattern bitwiseXOR with the scrambled horizontal coefficients only and the shuffled approximation coefficients aredivided into non-overlapping and equal sized blocks. Watermark embedding process is based on extractingthe (DCT middle frequencies of the encrypted approximation coefficients blocks. Comparison basedthreshold of the extracted DCT mid-band coefficients, watermark bits are embedded in the coefficients ofthe corresponding DCT middle frequencies. The experimental results show that the proposed algorithm isrobust against common signal processing attacks. The proposed algorithm is able to reduce encryption toone quarter of the image information. Statistical and differential analyses are performed to estimate thesecurity strength of the proposed algorithm. The results of the security analysis show that the proposedalgorithm provides a high security level for real time application.

  14. CHAOS-BASED ADVANCED ENCRYPTION STANDARD

    Abdulwahed, Naif B.

    2013-05-01

    This thesis introduces a new chaos-based Advanced Encryption Standard (AES). The AES is a well-known encryption algorithm that was standardized by U.S National Institute of Standard and Technology (NIST) in 2001. The thesis investigates and explores the behavior of the AES algorithm by replacing two of its original modules, namely the S-Box and the Key Schedule, with two other chaos- based modules. Three chaos systems are considered in designing the new modules which are Lorenz system with multiplication nonlinearity, Chen system with sign modules nonlinearity, and 1D multiscroll system with stair case nonlinearity. The three systems are evaluated on their sensitivity to initial conditions and as Pseudo Random Number Generators (PRNG) after applying a post-processing technique to their output then performing NIST SP. 800-22 statistical tests. The thesis presents a hardware implementation of dynamic S-Boxes for AES that are populated using the three chaos systems. Moreover, a full MATLAB package to analyze the chaos generated S-Boxes based on graphical analysis, Walsh-Hadamard spectrum analysis, and image encryption analysis is developed. Although these S-Boxes are dynamic, meaning they are regenerated whenever the encryption key is changed, the analysis results show that such S-Boxes exhibit good properties like the Strict Avalanche Criterion (SAC) and the nonlinearity and in the application of image encryption. Furthermore, the thesis presents a new Lorenz-chaos-based key expansion for the AES. Many researchers have pointed out that there are some defects in the original key expansion of AES and thus have motivated such chaos-based key expansion proposal. The new proposed key schedule is analyzed and assessed in terms of confusion and diffusion by performing the frequency and SAC test respectively. The obtained results show that the new proposed design is more secure than the original AES key schedule and other proposed designs in the literature. The proposed

  15. Enhanced Throughput AES Encryption

    Kunal Lala

    2012-09-01

    Full Text Available This paper presents our experience in implementing the Advanced Encryption Standard (AES algorithm. We have used 128 bit block size and 128 bit cipher key for the implementation. The AES also known as Rijndael algorithm is used to ensure security of transmission channels. Xilinx design tool 13.3 and Xilinx project navigator design tool are used for synthesis and simulation. Very high speed integrated circuit hardware description language (VHDL is used for coding. The fully pipelined design was implemented on Virtex 6 FPGA family and a throughput of 49.3Gbits/s was achieved with an operational frequency of 384.793 MHz.

  16. A Hybrid Approach for Detecting Stego Content in Corporate Mail Using Neural Network Based Simplified-Data Encryption Standard Algorithm

    P. T. Anitha

    2012-01-01

    Full Text Available Problem statement: The major growth of information technology is based on the security measures implemented. Steganography is a method which is used to give high level security. Approach: Today, email management and email authenticity must be unquestionable with strong chains of custody, constant availability and tamper-proof security. A secure communication can be achieved through neural based steganography. Email is insecure. Results: This research developed an application which can check the Email content of corporate mails by S-DES algorithm along with the neural networks back propagation approach. A new filtering algorithm is also developed which can used to extract only the JPG images from the corporate emails. Experimental research shows that this algorithm is more accurate and reliable than the conventional methods. Conclusion: We anticipate that this study can also give a clear picture of the current trends in Steganography and the experimental results indicate this method is valid in steganalysis. This method can be used for internet/network security.

  17. Decryption of pure-position permutation algorithms

    赵晓宇; 陈刚; 张亶; 王肖虹; 董光昌

    2004-01-01

    Pure position permutation image encryption algorithms,commonly used as image encryption investigated in this work are unfortunately frail under known-text attack.In view of the weakness of pure position permutation algorithm,we put forward an effective decryption algorithm for all pure-position permutation algorithms.First,a summary of the pure position permutation image encryption algorithms is given by introducing the concept of ergodic matrices.Then,by using probability theory and algebraic principles,the decryption probability of pure-position permutation algorithms is verified theoretically; and then,by defining the operation system of fuzzy ergodic matrices,we improve a specific decryption algorithm.Finally,some simulation results are shown.

  18. Algorithms for boundary detection in radiographic images

    Edge detecting techniques applied to radiographic digital images are discussed. Some algorithms have been implemented and the results are displayed to enhance boundary or hide details. An algorithm applied in a pre processed image with contrast enhanced is proposed and the results are discussed

  19. IMPROVED ALGORITHM FOR STRIPMAP SAR IMAGING

    2006-01-01

    This paper proposes a calibrated method for quasi-broadside side-looking mode SAR imaging with small squint angle and an improved method named as phase alignment algorithm of subaperture reference signal. The calibrated method adopts subaperture spotlighting algorithm of broadside mode to image the real data of quasi-broadside mode SAR, then based on the obtained image the small squint angle is estimated and the calibrated subaperture spotlighting algorithm of squint mode is employed to obtain the final image. The calibrated method can calibrate the abnormal region and obtain the correct image. The phase alignment algorithm of subaperture reference signal adjusts phases of respective subaperture reference signals in order to make them be in phase and constructs a new spotlighting window function for SAR imaging. Theoretical analysis shows that with the same sample data, the improved method can increase SAR imaging area in azimuth dimension. The methods are verified by the results of computer simulation.

  20. Optical encryption with cascaded fractional wavelet transforms

    BAO Liang-hua; CHEN Lin-fei; ZHAO Dao-mu

    2006-01-01

    On the basis of fractional wavelet transform, we propose a new method called cascaded fractional wavelet transform to encrypt images. It has the virtues of fractional Fourier transform and wavelet transform. Fractional orders, standard focal lengths and scaling factors are its keys. Multistage fractional Fourier transforms can add the keys easily and strengthen information security. This method can also realize partial encryption just as wavelet transform and fractional wavelet transform. Optical realization of encryption and decryption is proposed. Computer simulations confirmed its possibility.

  1. A fast chaotic encryption scheme based on piecewise nonlinear chaotic maps

    In recent years, a growing number of discrete chaotic cryptographic algorithms have been proposed. However, most of them encounter some problems such as the lack of robustness and security. In this Letter, we introduce a new image encryption algorithm based on one-dimensional piecewise nonlinear chaotic maps. The system is a measurable dynamical system with an interesting property of being either ergodic or having stable period-one fixed point. They bifurcate from a stable single periodic state to chaotic one and vice versa without having usual period-doubling or period-n-tippling scenario. Also, we present the KS-entropy of this maps with respect to control parameter. This algorithm tries to improve the problem of failure of encryption such as small key space, encryption speed and level of security

  2. High Lightweight Encryption Standard (HLES as an Improvement of 512-Bit AES for Secure Multimedia

    GUESMIA Seyf Eddine

    2016-01-01

    Full Text Available In today’s scenario, people share information to another people frequently using network. Due to this, more amount of information are so much private but some are less private. Therefore, the attackers or the hackers take the advantage and start attempting to steal the information since 2001. the symmetric encryption algorithm called 512-bit AES provides high level of security, but it's almost be impossible to be used in multimedia transmissions and mobile systems because of the need for more design area that effect in the use of large memory space in each round and the big encryption time that it takes. This paper presents an improvement of 512-bit AES algorithm with efficient utilization of resources such as processor and memory space. The proposed approach resists the linear and differential encrypt analysis and provides high security level using a 512-bit size of key block and data block and ameliorates the performance by minimizing the use of memory space and time encryption to be able to work in specific characteristics of resource-limited systems. The experimental results on several data (text, image, sound, video show that the used memory space is reduced to quarter, and the encryption time is reduced almost to the half. Therefore, the adopted method is very effective for encryption of multimedia data.

  3. Comparative Study of Image Denoising Algorithms in Digital Image Processing

    Aarti Kumari

    2015-11-01

    Full Text Available This paper proposes a basic scheme for understanding the fundamentals of digital image processing and the image denising algorithm. There are three basic operation categorized on during image processing i.e. image rectification and restoration, enhancement and information extraction. Image denoising is the basic problem in digital image processing. The main task is to make the image free from Noise. Salt & pepper (Impulse noise and the additive white Gaussian noise and blurredness are the types of noise that occur during transmission and capturing. For denoising the image there are some algorithms which denoise the image.

  4. TinySBSec-the new lightweight WSN link-layer encryption algorithm%TinySBSec-新型轻量级WSN链路层加密算法

    白恩健; 朱俊杰

    2014-01-01

    WSN is a kind of wireless network with constrained node resources. The research on the security strategy of the lightweight link-layer is appropriate for the WSN systems working under various kinds of application environ-ments;in addition, the effects are marked. This paper describes a new lightweight WSN link-layer encryption algo-rithm based on the advantages of the stream cipher and block cipher. The security strategy of the new algorithm was analyzed and the new algorithm was tested by using statistical methods. The results show that the new algorithm has good safety performance.%WSN是一种节点资源受限的无线网络,其链路层安全策略的轻量化研究适合于各种应用环境的WSN系统,且效果显著。结合序列密码和分组密码各自的优势,提出了一种新型轻量的WSN链路层加密算法-TinySBSec。对算法的安全性进行了理论分析,并且采用统计学方法,对该算法的安全性能进行了测试,结果证明算法具有良好的安全性能。

  5. An iterative image reconstruction algorithm for SPECT

    Properties of two algorithms for iterative reconstruction of SPECT images, LS-MLEM and LS-OSEM, are studied and compared with the ML-EM algorithm in this paper. By using projection data of heavy-noise, their effectiveness in improving SPECT image quality is evaluated. A phantom with hot and cold lesion is used in the investigation. The reconstructed images using LS-MLEM or LS-OSEM show that there is not a rapid increase in image noise, and the 'best' estimate is assuming that the reconstructed images satisfy the statistical model. The major advantage of using LS-MLEM or LS-OSEM algorithm in SPECT imaging is in their ability to accurately control for heavy-noise. And LS-OSEM algorithm obviously improves the convergence rate. (authors)

  6. An Optical Encryption and Decryption Method and System

    2000-01-01

    The invention relates to securing of information utilising optical imaging technologies and more specifically to phase encryption and decryption of images. An image is encrypted into a mask having a plurality of mask resolution elements (Xm, Ym) by encoding the image using e.g. a phase mask with an...... encoded phase value phi (Xm, Ym) and an encoded amplitude value a (Xm, Ym), and by further encrypting the mask (using e.g. a spatial light modulator) by addition of an encrypting phase value phi c (Xm, Ym) to the encoded phase value phi (Xm, Ym) and by multiplication of an encrypting amplitude value ac...

  7. A RANDOMIZED SELECTIVE ENCRYPTION USING HASHING TECHNIQUE FOR SECURING VIDEO STREAMS

    Lizyflorance. C

    2012-11-01

    Full Text Available Digital video transmissions are widely used in network nowadays. Hence, securing its contents and keeping privacy is vital. Several encryption algorithms have been proposed earlier to achieve securevideo transmission. But altogether attaining efficiency, security and flexibility is a major challenge. To transmit a digital video, encryption is necessary to protect its contents from attacks. As the size of the videos are usually large their contents has to be compressed before transmission. Encryption is applied on the video content after compression. One of the encryption technique selective encryption is used for encrypting video. It encrypts only a subset of data. The selective encryption algorithm reduces the amount of the data to be encrypted and achieves a required level of security. In this paper we study the existing selective encryption algorithm and its classifications. The challenges in the selective encryptionalgorithms and some future directions are presented.

  8. Comparative Study of Image Denoising Algorithms in Digital Image Processing

    Aarti Kumari; Gaurav Pushkarna

    2015-01-01

    This paper proposes a basic scheme for understanding the fundamentals of digital image processing and the image denising algorithm. There are three basic operation categorized on during image processing i.e. image rectification and restoration, enhancement and information extraction. Image denoising is the basic problem in digital image processing. The main task is to make the image free from Noise. Salt & pepper (Impulse) noise and the additive white Gaussian noise and blurredness are th...

  9. Comparative Study of Image Denoising Algorithms in Digital Image Processing

    Aarti; Gaurav Pushkarna

    2014-01-01

    This paper proposes a basic scheme for understanding the fundamentals of digital image processing and the image denising algorithm. There are three basic operation categorized on during image processing i.e. image rectification and restoration, enhancement and information extraction. Image denoising is the basic problem in digital image processing. The main task is to make the image free from Noise. Salt & pepper (Impulse) noise and the additive white Gaussian noise and blurrednes...

  10. A cubic map chaos criterion theorem with applications in generalized synchronization based pseudorandom number generator and image encryption

    This paper sets up a chaos criterion theorem on a kind of cubic polynomial discrete maps. Using this theorem, Zhou-Song's chaos criterion theorem on quadratic polynomial discrete maps and generalized synchronization (GS) theorem construct an eight-dimensional chaotic GS system. Numerical simulations have been carried out to verify the effectiveness of theoretical results. The chaotic GS system is used to design a chaos-based pseudorandom number generator (CPRNG). Using FIPS 140-2 test suit/Generalized FIPS 140-2, test suit tests the randomness of two 1000 key streams consisting of 20 000 bits generated by the CPRNG, respectively. The results show that there are 99.9%/98.5% key streams to have passed the FIPS 140-2 test suit/Generalized FIPS 140-2 test. Numerical simulations show that the different keystreams have an average 50.001% same codes. The key space of the CPRNG is larger than 21345. As an application of the CPRNG, this study gives an image encryption example. Experimental results show that the linear coefficients between the plaintext and the ciphertext and the decrypted ciphertexts via the 100 key streams with perturbed keys are less than 0.00428. The result suggests that the decrypted texts via the keystreams generated via perturbed keys of the CPRNG are almost completely independent on the original image text, and brute attacks are needed to break the cryptographic system

  11. A cubic map chaos criterion theorem with applications in generalized synchronization based pseudorandom number generator and image encryption

    Yang, Xiuping, E-mail: yangxiuping-1990@163.com; Min, Lequan, E-mail: minlequan@sina.com; Wang, Xue, E-mail: wangxue-20130818@163.com [Schools of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083 (China)

    2015-05-15

    This paper sets up a chaos criterion theorem on a kind of cubic polynomial discrete maps. Using this theorem, Zhou-Song's chaos criterion theorem on quadratic polynomial discrete maps and generalized synchronization (GS) theorem construct an eight-dimensional chaotic GS system. Numerical simulations have been carried out to verify the effectiveness of theoretical results. The chaotic GS system is used to design a chaos-based pseudorandom number generator (CPRNG). Using FIPS 140-2 test suit/Generalized FIPS 140-2, test suit tests the randomness of two 1000 key streams consisting of 20 000 bits generated by the CPRNG, respectively. The results show that there are 99.9%/98.5% key streams to have passed the FIPS 140-2 test suit/Generalized FIPS 140-2 test. Numerical simulations show that the different keystreams have an average 50.001% same codes. The key space of the CPRNG is larger than 2{sup 1345}. As an application of the CPRNG, this study gives an image encryption example. Experimental results show that the linear coefficients between the plaintext and the ciphertext and the decrypted ciphertexts via the 100 key streams with perturbed keys are less than 0.00428. The result suggests that the decrypted texts via the keystreams generated via perturbed keys of the CPRNG are almost completely independent on the original image text, and brute attacks are needed to break the cryptographic system.

  12. ALE: AES-based lightweight authenticated encryption

    Bogdanov, Andrey; Mendel, Florian; Regazzoni, Francesco;

    2014-01-01

    In this paper, we propose a new Authenticated Lightweight Encryption algorithm coined ALE. The basic operation of ALE is the AES round transformation and the AES-128 key schedule. ALE is an online single-pass authenticated encryption algorithm that supports optional associated data. Its security...... is at least 2.5 times more performant than the alternatives in their smallest implementations by requiring only about 4 AES rounds to both encrypt and authenticate a 128-bit data block for longer messages. When using the AES-NI instructions, ALE outperforms AES-GCM, AES-CCM and ASC-1 by a...

  13. Improved decryption quality and security of a joint transform correlator-based encryption system

    Some image encryption systems based on modified double random phase encoding and joint transform correlator architecture produce low quality decrypted images and are vulnerable to a variety of attacks. In this work, we analyse the algorithm of some reported methods that optically implement the double random phase encryption in a joint transform correlator. We show that it is possible to significantly improve the quality of the decrypted image by introducing a simple nonlinear operation in the encrypted function that contains the joint power spectrum. This nonlinearity also makes the system more resistant to chosen-plaintext attacks. We additionally explore the system resistance against this type of attack when a variety of probability density functions are used to generate the two random phase masks of the encryption–decryption process. Numerical results are presented and discussed. (paper)

  14. Digital Watermarking through Embedding of Encrypted and Arithmetically Compressed Data into Image using Variable-Length Key

    Sabyasachi Samanta; Saurabh Dutta; ,Goutam Sanyal

    2011-01-01

    In this paper, we have encrypted a text to an array of data bits through arithmetic coding technique. Forthis, we have assigned a unique range for both, a number of characters and groups using those. Usingunique range we may assign range only 10 characters. If we want to encrypt a large number ofcharacters, then every character has to assign a range with their group range of hundred, thousand andso on. Long textual message which have to encrypt, is subdivided into a number of groups with fewc...

  15. Algorithms for reconstructing images for industrial applications

    Several algorithms for reconstructing objects from their projections are being studied in our Laboratory, for industrial applications. Such algorithms are useful locating the position and shape of different composition of materials in the object. A Comparative study of two algorithms is made. The two investigated algorithsm are: The MART (Multiplicative - Algebraic Reconstruction Technique) and the Convolution Method. The comparison are carried out from the point view of the quality of the image reconstructed, number of views and cost. (Author)

  16. A novel method of space-domain image encryption%一种数字图像空域加密新算法

    王学刚; 杨素林

    2012-01-01

    In view of the feature of digital image and on the basis of compound chaos, an images encryption algorithm is proposed. Firstly, it divides the image into two halves. One half has the four high bits,and the other has four low bits. Secondly, under the control of compound chaos, it scrambles positions of pixels, replaces pixels, and diffuses pixels in the two halves respectively. Thirdly, it combines the two halves correspondingly to get an image with 8 bits per pixel, then repalces and diffuses 8-bit pixels. After iterating the two upper procedures 2 times, the cipher-text is obtained. Theory analysis and experiments show that the algorithm is convenient to realize in parallel, takes strong sensitivity with huge key space, conforms to confusion and diffusion principles of cryptography, and gets high security.%针对数字图像的特点,在构造复合混沌系统的基础上提出一种加密算法:首先将4个高比特位和4个低比特位拆开形成2个新的图像,新图像中每个像素只有4比特;然后利用复合混沌系统分别置乱这2个新图像中像素的位置,并分别对它们进行替换和扩散;再后将高、低平面的数据对应组合形成8比特每像素的图像,并用混沌序列中后续的数值对8比特的像素进行代换和扩散.如此迭代2轮,最后得到密文图像.理论和实验结果表明该算法具有易于并行实现的特性,密钥空间大,敏感性强,符合密码学的混淆、扩散原则,安全性高.

  17. Microwave Imaging Equipment And Algorithms

    Semenchik, V.; Pahomov, V.

    2004-01-01

    Microwave holographic imaging is set of methods for obtaining images of hidden objects and determining their electrical properties. The essence of these methods is image reconstruction from measurements of scattered electromagnetic field. The microwave holography is applied in medicine, industry, military, earth sciences etc. The paper presents the description of acting multifrequency microwave holographic experimental set-up.

  18. 基于MD5加密的Tornado码复制算法改进%An improved algorithm based on MD5 encryption Tornado code

    骆正平; 陈中育; 林郁峰; 吴星同

    2015-01-01

    Tornado code based replication algorithm had the advantages of faster encoding and decoding, and could also recover the original data when some data were missing, but when the algorithm was applied to a dis-tributed storage system, the presence of data would be susceptible to theft, tampering risk. For this reason, several optimization strategies were proposed to improve the replication algorithm based on Tornado code:1 ) an encryption mechanism into replication algorithm was introduced in case of even some data were stolen there would be no worry about information leak. 2)the raw data using the MD5 algorithm to generate digital finger-prints produced a digital fingerprint when retrieving data from a distributed storage system with local digital fin-gerprint comparison, it would be easy to determine whether the data had been tampered with.%基于Tornado码的复制算法具有编解码速度比较快、部分数据丢失时亦能被恢复的优点,但将该算法应用于分布式存储系统时,存在数据易被窃取、篡改的风险。为此,对基于Tornado码的复制算法提出了改进:1)引入加密机制,使数据即使被窃取时也不用担心泄密;2)对原始数据使用MD5算法产生数字指纹,当从分布式存储系统取回数据时,计算数字指纹并与本地的数字指纹对比,就可以判断数据是否被篡改。

  19. An improved algorithm based on MD5 encryption Tornado code%基于MD5加密的Tornado码复制算法改进

    骆正平; 陈中育; 林郁峰; 吴星同

    2015-01-01

    基于Tornado码的复制算法具有编解码速度比较快、部分数据丢失时亦能被恢复的优点,但将该算法应用于分布式存储系统时,存在数据易被窃取、篡改的风险。为此,对基于Tornado码的复制算法提出了改进:1)引入加密机制,使数据即使被窃取时也不用担心泄密;2)对原始数据使用MD5算法产生数字指纹,当从分布式存储系统取回数据时,计算数字指纹并与本地的数字指纹对比,就可以判断数据是否被篡改。%Tornado code based replication algorithm had the advantages of faster encoding and decoding, and could also recover the original data when some data were missing, but when the algorithm was applied to a dis-tributed storage system, the presence of data would be susceptible to theft, tampering risk. For this reason, several optimization strategies were proposed to improve the replication algorithm based on Tornado code:1 ) an encryption mechanism into replication algorithm was introduced in case of even some data were stolen there would be no worry about information leak. 2)the raw data using the MD5 algorithm to generate digital finger-prints produced a digital fingerprint when retrieving data from a distributed storage system with local digital fin-gerprint comparison, it would be easy to determine whether the data had been tampered with.

  20. Image processing technologies algorithms, sensors, and applications

    Aizawa, Kiyoharu; Suenaga, Yasuhito

    2004-01-01

    Showcasing the most influential developments, experiments, and architectures impacting the digital, surveillance, automotive, industrial, and medical sciences, Image Processing Technologies tracks the evolution and advancement of computer vision and image processing (CVIP) technologies, examining methods and algorithms for image analysis, optimization, segmentation, and restoration. It focuses on recent approaches and techniques in CVIP applications development and explores various coding methods for individual types of 3-D images. This text/reference brings researchers and specialists up-to-

  1. PERFORMANCE EVALUATION OF CHAOTIC ENCRYPTION TECHNIQUE

    Ancy Mariam Babu

    2013-01-01

    Full Text Available Drastic growth in multimedia communication resulted to numerous security issues in the transmission of data. Moreover, the network used for the digital communication does not provide much security for the data transfer. During this time, tens of millions people using the internet options for essential communication and is being a tool for commercial field increased, So that security is an enormously important issue to deal with. We need to be protected confidentiality of data and provide secure connections for it. Hence we necessitate recognizing the different aspects of security and their applications. Many of these applications ranging from secure commerce, protecting passwords or pin and payments to private communications. As we know that, Cryptography is now becoming an essential aspect of the secure communication. Cryptography is the science of writing secret code with confident algorithm and key. The basic components of cryptography are encryption and decryption algorithms, digital signature and hashed message authentication code. We know that encryption is the synonym of cryptography. Different kinds of encryption are used in this modern era. Chaotic encryption is the type of the encryption which has adopted the concept of chaos. In this study, we are studying the history of cryptography until chaotic cryptography and analyzing the performance of chaotic encryption technique. The evaluation is performed in terms of encryption speed, the CPU utilization with time and the battery power consumption. The experimental results are specified the efficiency of the algorithms.

  2. Modified Projective Synchronization between Different Fractional-Order Systems Based on Open-Plus-Closed-Loop Control and Its Application in Image Encryption

    Hongjuan Liu

    2014-01-01

    Full Text Available A new general and systematic coupling scheme is developed to achieve the modified projective synchronization (MPS of different fractional-order systems under parameter mismatch via the Open-Plus-Closed-Loop (OPCL control. Based on the stability theorem of linear fractional-order systems, some sufficient conditions for MPS are proposed. Two groups of numerical simulations on the incommensurate fraction-order system and commensurate fraction-order system are presented to justify the theoretical analysis. Due to the unpredictability of the scale factors and the use of fractional-order systems, the chaotic data from the MPS is selected to encrypt a plain image to obtain higher security. Simulation results show that our method is efficient with a large key space, high sensitivity to encryption keys, resistance to attack of differential attacks, and statistical analysis.

  3. Algorithms for image processing and computer vision

    Parker, J R

    2010-01-01

    A cookbook of algorithms for common image processing applications Thanks to advances in computer hardware and software, algorithms have been developed that support sophisticated image processing without requiring an extensive background in mathematics. This bestselling book has been fully updated with the newest of these, including 2D vision methods in content-based searches and the use of graphics cards as image processing computational aids. It's an ideal reference for software engineers and developers, advanced programmers, graphics programmers, scientists, and other specialists wh

  4. An Ensemble Classification Algorithm for Hyperspectral Images

    K.Kavitha

    2014-04-01

    Full Text Available Hyperspectral image analysis has been used for many purposes in environmental monitoring, remote sensing, vegetation research and also for land cover classification. A hyperspectral image consists of many layers in which each layer represents a specific wavelength. The layers stack on top of one another making a cube-like image for entire spectrum. This work aims to classify the hyperspectral images and to produce a thematic map accurately. Spatial information of hyperspectral images is collected by applying morphological profile and local binary pattern. Support vector machine is an efficient classification algorithm for classifying the hyperspectral images. Genetic algorithm is used to obtain the best feature subjected for classification. Selected features are classified for obtaining the classes and to produce a thematic map. Experiment is carried out with AVIRIS Indian Pines and ROSIS Pavia University. Proposed method produces accuracy as 93% for Indian Pines and 92% for Pavia University.

  5. 基于自适应遗传算法的数字混沌加密技术研究%Research on Digital Chaotic Encryption Technology Based on Adaptive Genetic Algorithms

    马书月; 王剑

    2011-01-01

    Security for network operation and data transmission for providing reliable business have become one of the present research hotspots. The traditional encryption technology still has some shortages. Security vulnerabilities of encryption technology itself were caused by lower efficiency descend, reliability, safety hazard and stability hidden trouble. Firstly, according to network business encryption features, an adaptive adjustment was researched. Based on crossover probability Pc and mutation probability Pm, an adaptive genetic algorithm was set up. Then based on infor-mation hiding model, digital mapping mechanism was established. Finally, the plaintext in the encryption process was grouped as data flow, based on adaptive genetic algorithm, and each time a data group was encrypted. The encryption method was determined by digital chaos mapping function. Simulation experiments show that the encryption technology has the features of adaptive global optimization, low computing complexity and high reliability.%研究优化网络信息安全问题.传统的加密技术存在一些安全系统可部署性较差,加密技术自身造成的安全漏洞容易导致效率下降、可靠性较低等安全和稳定性隐患,依据网络业务加密特点自适应调整交叉概率Pc和变异概率Pm值,提出了一种自适应遗传算法数字加密技术,算法基于信息混沌迭代模型,建立混沌数字映射8制,最后在加密过程中将明文分组为数据流,依据自适应遗传算法,每次加密一个数据包,其加密方式由数字混沌映射函数确定.仿真结果表明,该加密技术具有自适应优化全局、计算复杂度低和可靠性高等优点.

  6. Encryption And Portable Data Storage

    Cynthia L. Knott

    2011-04-01

    Full Text Available The protection of data is key issue in today’s world. The wide of availability and use of portable technologies such as USB flash has increased concern about securing the data resides on these devices. Because USB flash drives are small, relatively inexpensive, and easy to use, the security of the information stored on these thumb drives is on-going concern. A number of approaches to safeguarding the information stored on these drives are available. This paper examines one approach to this goal through the use of encryption. This method encrypts all the data on the drive. In addition the fact the data on the drive is encrypted is not visually obvious when viewing the contents of the disk. The proposed approach uses publically available and free encryption algorithms. A user password is needed to view and access the data that has been encrypted.  The proposed methodology is quick and easy to use. Individuals who routinely carry around their USB drives need to be able to decrypt and encrypt the device quickly and conveniently. Furthermore, if the device is lost, it is still possible with the method advocated in this paper to include information about how to return the device to the owner without compromising the secured data on the drive. Without encrypting the data on portable drives, the user risks the disclosure of information. This paper argues that portable storage should be secured and suggests a way to secure the data through password and encryption that further enhances the usability and flexibility of the USB flash drive.  The paper includes the results and analysis of an undergraduate student survey that determined what habits and practices they followed with respect to securing their personal data and files.  Some of the questions included in the analysis are the following: Do you encrypt your USB flash drive?Do you use any type of security for your USB flash drive?How important do you think security is for a flash drive? (A

  7. A Self-synchronizing Stream Encryption Scheme Based on One-Dimensional Coupled Map Lattices

    MA Hui; ZHU Kai-En; CHEN Tian-Lun

    2007-01-01

    We present a self-synchronizing stream encryption scheme based on one-dimensional coupled map lattices which is introduced as a model with the essential features of spatiotemporal chaos,and of great complexity and diffusion capability of the little disturbance in the initial condition.To evaluate the scheme,a series of statistical tests are employed,and the results show good random-look nature of the ciphertext.Furthermore,we apply our algorithm to encrypt a grey-scale image to show the key sensitivity.

  8. CONSTRUCTION OF THE ENCRYPTION MATRIX BASED ON CHEBYSHEV CHAOTIC NEURAL NETWORKS

    Zou Ajin; Wu Wei; Li Renfa; Li Yongjiang

    2012-01-01

    The paper proposes a novel algorithm to get the encryption matrix.Firstly,a chaotic sequence generated by Chebyshev chaotic neural networks is converted into a series of low-order integer matrices from which available encryption matrices are selected.Then,a higher order encryption matrix relating real world application is constructed by means of tensor production method based on selected encryption matrices.The results show that the proposed algorithm can produce a "one-time pad cipher" encryption matrix with high security; and the encryption results have good chaos and autocorrelation with the natural frequency of the plaintext being hidden and homogenized.

  9. Three-dimensional photon counting double-random-phase encryption.

    Cho, Myungjin; Javidi, Bahram

    2013-09-01

    In this Letter, we present a three-dimensional (3D) photon counting double-random-phase encryption (DRPE) technique using passive integral imaging. A 3D photon counting DRPE can encrypt a 3D scene and provides more security and authentications due to photon counting Poisson nonlinear transformation on the encrypted image. In addition, 3D imaging allows verification of the 3D object at different depths. Preliminary results and performance evaluation have been presented. PMID:23988912

  10. Image Mosaicing Algorithm for Rolled Fingerprint Construction

    贺迪; 荣钢; 周杰

    2002-01-01

    Fingerprint identification is one of the most important biometric authentication methods. However, current devices for recording digital fingerprints can only capture plain-touch fingerprints. Rolled fingerprints have much more information for recognition, so a method is needed to construct a rolled fingerprint from a series of plain-touch fingerprints. This paper presents a novel algorithm for image mosaicing for real time rolled fingerprint construction in which the images are assembled with corrections to create a smooth, non-fragmented rolled fingerprint in real time. Experimental results demonstrate its effectiveness by comparing it with other conventional algorithms.

  11. Algorithm for Fast Registration of Radar Images

    Subrata Rakshit

    2002-07-01

    Full Text Available Radar imagery provides an all-weather and 24 h coverage, making it ideal for critical defence applications. In some applications, multiple images acquired of an area need to be registered for further processing. Such situations arise for battlefield surveillance based on satellite imagery. The registration has to be done between an earlier (reference image and a new (live image. For automated surveillance, registration is a prerequisite for change detection. Speed is essential due to large volumes of data involved and the need for quick responses. The registration transformation is quite simple, being mainly a global translation. (Scale and rotation corrections can be applied based on known camera parameters. The challenge lies in the fact that the radar images are not as feature-rich as optical images and the image content variation can be as high as 90 per cent. Even though the change on the ground may not be drastic, seasonal variations can significantly alter the radar signatures of ground, vegetation, and water bodies. This necessitates a novel approach different from the techniques developed for optical images. An algorithm has been developed that leads to fast registration of radar images, even in the presence of specular noise and significant scene content variation. The key features of this approach are adaptability to sensor/terrain types, ability to handle large content variations and false positive rejection. The present work shows that this algorithm allows for various cost-performance trade-offs, making it suitable for a wide variety of applications. The algorithm, in various cost-performance configurations, is tested on a set of ERS images. Results of such tests have been reported, indicating the performance of the algorithm for various cost-performance trade-offs.

  12. Data Based Text Encrypting in Audio

    Bommala Suneel Kumar; Satyanarayana, S.

    2013-01-01

    Nowadays data authentication plays a major for the secrete transmission of the data respectively. Here in this data oriented authentication involves encryption followed by the respective decryption. Where in the encryption process takes place in the transmitter end while decryption takes place or handled at the receiver end respectively. Here an algorithm is designed based on the above strategy where complete privacy is maintained by the system. This one of the data hiding technique. Some of ...

  13. Color Digital Image Encryption Using Wavelet Transform and Chaotic Sequence%彩色数字图像的小波变换和混沌序列加密

    张定会; 许赛赛; 余日; 张建伟

    2011-01-01

    根据彩色数字图像的基本特点,运用数字图像加密和解密原理,将离散小波变换和离散混沌序列有机地结合起来,研究了彩色数字图像的小波变换和混沌序列的加密和解密方法;对原始图像进行加密实质是利用混沌序列对其低频小波系数进行加密,对加密图像进行解密实质是利用混沌序列对其低频小波系数进行解密}研究的彩色数字图像加解密方法,为彩色数字图像加密提供了一种有效可行的方法,不仅能够使加密彩色数字图像具有理想的加密效果,而且能够保证加密彩色数字图像足够的安全.%According to the basic characteristic of color digital image, using the encrypting and decrypting theorem of digital image, organically combining discrete wavelet transform with discrete chaotic sequence, the encryption and decryption of color digital image based on wavelet transform and chaotic sequence has been studied. The encryption of original images is to use chaotic sequences to encrypt its low frequency wavelet coefficients. The decryption of encrypted images is to use chaotic sequences to decrypt its low frequency wavelet coefficients. The encryption and decryption of color digital image studied by this paper provides an effective and feasibJe method for color digital image encryption, and not only can make the encrypted color digital image have perfect encryption effect, but also can ensure its sufficient security.

  14. The Peacock Encryption Method

    Kestila, Antti Alexander

    2010-01-01

    Here is described a preliminary method that enables secure 'anti-search-engine' encryption, where the middleman can participate in the encrypted information exchange, without being able to understand the exchanged information, encrypted using a one-way function, as well as being unaware of one of two main exchange participants.

  15. Side-Channel Attack on Elliptic Curve Encryption Algorithm%椭圆曲线加密算法的边信道攻击

    陈力; 葛万成

    2014-01-01

    Elliptic-curve encryption algorithm is currently known as the best algorithm in the public-key crypto-system. In order to break it, a side-channel information attack is designed and used. With near-field probe to measure the power traces generated by the chip, the relation between the power traces and secret key is tried to find out. In this way, the mathematical problems can be avoided. In the experiment, oscilloscope is used to ac-quire the data from the crypto device and then to analyze them. From the differential power analysis, the secret key may be found. The experiment shows that the side-channel attack could work effectively.%椭圆曲线加密算法是目前已知的公共密钥体系中加密强度最高的一种算法,为了将其破解,采用边信道攻击,即通过对密码机在加密过程中的功率变化的分析来尝试获取密钥信息,从而绕过了从数学上破译椭圆曲线密钥极其困难的问题。所搭建的实验平台,利用示波器探测正在运行加密程序的设备,对其中进行差分功率分析,从而找到加密规则。实验结果验证了所采用方法的有效性。

  16. Image enhancement based on edge boosting algorithm

    Ngernplubpla, Jaturon; Chitsobhuk, Orachat

    2015-12-01

    In this paper, a technique for image enhancement based on proposed edge boosting algorithm to reconstruct high quality image from a single low resolution image is described. The difficulty in single-image super-resolution is that the generic image priors resided in the low resolution input image may not be sufficient to generate the effective solutions. In order to achieve a success in super-resolution reconstruction, efficient prior knowledge should be estimated. The statistics of gradient priors in terms of priority map based on separable gradient estimation, maximum likelihood edge estimation, and local variance are introduced. The proposed edge boosting algorithm takes advantages of these gradient statistics to select the appropriate enhancement weights. The larger weights are applied to the higher frequency details while the low frequency details are smoothed. From the experimental results, the significant performance improvement quantitatively and perceptually is illustrated. It can be seen that the proposed edge boosting algorithm demonstrates high quality results with fewer artifacts, sharper edges, superior texture areas, and finer detail with low noise.

  17. ALGORITHMIC IMAGING APPROACH TO IMPOTENCE

    Mahyar Ghafoori

    2012-05-01

    Full Text Available Impotence is a common problem that has great impact on the quality of life. Clinical evaluation usually can exclude endocrinologic imbalance, neurogenic dysfunction, and psychological problems as the etiology. A patient who fails to get an erection after vasoactive medications which are injected probably, has hemodynamic impotence. Dynamic studies that include imaging techniques are now available to discriminate between arterial and venous pathology.Doppler ultrasound with color flow and spectral analysis,dynamic infusion corpus cavernosometry and cavernosography, and selective internal pudendal arteriography are outpatient diagnostic procedures that will differentiate, image and quantify the abnormalities in patients with hemodynamic impotence. Not all tests are needed in every patient. Each of these examinations is preceded with the intracavernosal injection of vasoactive medication. Papaverine hydrochloride, phentolamine mesylate, or prostaglandin El will overcome normal sympathetic tone and produce an erection by smooth muscle relaxation and arterial dilatation in a normal patient. Color-flow Doppler and spectral analysis will showthe cavernosal arteries and can identify the hemodynamic effects of stricture or occlusion. Peak systolic velocity is measured. Normal ranges are well established. Spectral analysis also is used to predict the presence of venous disease. Sizable venous leaks in the dorsal penile vein are readily imaged.While the technique may not adequately identify low-grade venous pathology, it will identify the size and location of fibrous plaque formation associated with Peyronie's disease. Cavernosography or cavernosometry is a separate procedure that will quantitate the severity of venousincompetence as well as specifically identify the various avenues of systemic venous return that must be localized if venous occlusive therapy is chosen. In this study, the peak arterial systolic occlusion pressure is quantified during

  18. A Secure and Robust CDMA Digital Image Watermarking Algorithm Based on DWT2, YIQ Color Space and Arnold Transform

    Mehdi Khalil

    2011-01-01

    In this paper, a secure and robust cryptographic CDMA watermark algorithm based on DWT2, YIQ color space and Arnold transform is proposed. In the approach, for more security of watermark, the binary watermark image W, after scrambling with Arnold cat map is converted to a sequence and then, to determine the pixel to be used on a given key, a random binary sequence R of size n is adopted to encrypt the watermark using a pseudo-random number generator; where n is the size of the watermark. Afte...

  19. SEMI-FRAGILE WATERMARKING ALGORITHM FOR IMAGE TAMPERS LOCALIZATION AND RECOVERY

    Jiang Xuemei; Liu Quan

    2008-01-01

    Two watermarks are embedded into the original image. One is the authentication watermark generated by secret key, which is embedded into the sub-LSB (Least Significant Bit) of the original image for tamper localization; the other is the recovery watermark for tamper recovering. The original image is divided into 8×8 blocks and each block is transformed by Discrete Cosine Transform(DCT). For each block, some lower frequency DCT coefficients are chosen to be quantized and binary encoded so as to gain the recovery watermark of each block, and the recovery watermark is embedded into the LSB of another block by chaos encryption and authentication chain technology. After the two watermarks being detected, the location of any minute changes in image can be detected, and the tampered image data can be recovered effectively. In the paper, the number of coefficients and their bit lengths are carefully chosen in order to satisfy with the payload of each block and gain the capability of self-recovering. The proposed algorithm can well resist against possible forged attacks. Experimental results show that the watermark generated by the proposed algorithm is sensitive to tiny changes in images, and it has higher accuracy of tamper localization and good capability of the tamper recovery.

  20. An Efficient Encryption Algorithm for P2P Networks Robust Against Man-in-the-Middle Adversary

    Roohallah Rastaghi

    2012-11-01

    Full Text Available Peer-to-peer (P2P networks have become popular as a new paradigm for information exchange and are being used in many applications such as file sharing, distributed computing, video conference, VoIP, radio and TV broadcasting. This popularity comes with security implications and vulnerabilities that need to be addressed. Especially duo to direct communication between two end nodes in P2P networks, these networks are potentially vulnerable to Man-in-the-Middle attacks. In this paper, we propose a new public-key cryptosystem for P2P networks that is robust against Man-in-the-Middle adversary. This cryptosystem is based on RSA and knapsack problems. Our precoding-based algorithm uses knapsack problem for performing permutation and padding random data to the message. We show that comparing to other proposed cryptosystems, our algorithm is more efficient and it is fully secure against an active adversary.

  1. Experimental Study of Fractal Image Compression Algorithm

    Chetan R. Dudhagara

    2012-08-01

    Full Text Available Image compression applications have been increasing in recent years. Fractal compression is a lossy compression method for digital images, based on fractals. The method is best suited for textures and natural images, relying on the fact that parts of an image often resemble other parts of the same image. In this paper, a study on fractal-based image compression and fixed-size partitioning will be made, analyzed for performance and compared with a standard frequency domain based image compression standard, JPEG. Sample images will be used to perform compression and decompression. Performance metrics such as compression ratio, compression time and decompression time will be measured in JPEG cases. Also the phenomenon of resolution/scale independence will be studied and described with examples. Fractal algorithms convert these parts into mathematical data called "fractal codes" which are used to recreate the encoded image. Fractal encoding is a mathematical process used to encode bitmaps containing a real-world image as a set of mathematical data that describes the fractal properties of the image. Fractal encoding relies on the fact that all natural, and most artificial, objects contain redundant information in the form of similar, repeating patterns called fractals.

  2. Image completion algorithm based on texture synthesis

    Zhang Hongying; Peng Qicong; Wu Yadong

    2007-01-01

    A new algorithm is proposed for completing the missing parts caused by the removal of foreground or background elements from an image of natural scenery in a visually plausible way.The major contributions of the proposed algorithm are: (1) for most natural images, there is a strong orientation of texture or color distribution.So a method is introduced to compute the main direction of the texture and complete the image by limiting the search to one direction to carry out image completion quite fast; (2) there exists a synthesis ordering for image completion.The searching order of the patches is denned to ensure the regions with more known information and the structures should be completed before filling in other regions; (3) to improve the visual effect of texture synthesis, an adaptive scheme is presented to determine the size of the template window for capturing the features of various scales.A number of examples are given to demonstrate the effectiveness of the proposed algorithm.

  3. The Extensive Bit-level Encryption System (EBES)

    Satyaki Roy

    2013-01-01

    In the present work, the Extensive Bit-level Encryption System (EBES), a bit-level encryption mechanism has been introduced. It is a symmetric key cryptographic technique that combines advanced randomization of bits and serial bitwise feedback generation modules. After repeated testing with a variety of test inputs, frequency analysis, it would be safe to conclude that the algorithm is free from standard cryptographic attacks. It can effectively encrypt short messages and passwords.

  4. A Survey on Keyword Based Search over Outsourced Encrypted Data

    S. Evangeline Sharon

    2013-04-01

    Full Text Available To ensure security, encryption techniques play a major role when data are outsourced to the cloud. Problem of retrieving the data from the cloud servers is considered. Many searching techniques are used for retrieving the data. This study focused on a set of keyword based search algorithms. It provides secure data retrieval with high efficiency. It concludes Ranked Searchable Symmetric Encryption (RSSE scheme meant to be best methodology for searching the encrypted data.

  5. LSB Based Quantum Image Steganography Algorithm

    Jiang, Nan; Zhao, Na; Wang, Luo

    2016-01-01

    Quantum steganography is the technique which hides a secret message into quantum covers such as quantum images. In this paper, two blind LSB steganography algorithms in the form of quantum circuits are proposed based on the novel enhanced quantum representation (NEQR) for quantum images. One algorithm is plain LSB which uses the message bits to substitute for the pixels' LSB directly. The other is block LSB which embeds a message bit into a number of pixels that belong to one image block. The extracting circuits can regain the secret message only according to the stego cover. Analysis and simulation-based experimental results demonstrate that the invisibility is good, and the balance between the capacity and the robustness can be adjusted according to the needs of applications.

  6. Digital image processing an algorithmic approach with Matlab

    Qidwai, Uvais

    2009-01-01

    Introduction to Image Processing and the MATLAB EnvironmentIntroduction Digital Image Definitions: Theoretical Account Image Properties MATLAB Algorithmic Account MATLAB CodeImage Acquisition, Types, and File I/OImage Acquisition Image Types and File I/O Basics of Color Images Other Color Spaces Algorithmic Account MATLAB CodeImage ArithmeticIntroduction Operator Basics Theoretical TreatmentAlgorithmic Treatment Coding ExamplesAffine and Logical Operations, Distortions, and Noise in ImagesIntroduction Affine Operations Logical Operators Noise in Images Distortions in ImagesAlgorithmic Account

  7. Signal and reference wave dually encrypted digital holographic system

    ZHU YiChao; ZHANG JiaSen; GONG QiHuang

    2008-01-01

    We propose a secure digital holographic system with signal and reference waves dually encrypted. Two random phase masks are used to encrypt the images in the input and the Fourier planes. The reference beam is phase encoded by another random phase mask. The encrypted image and the key are recorded by a CCD camera. The data can be processed or transferred directly by computer. We theoretically and experimentally demonstrate encryption and decryption of multiple images and the results show a high quality and good fault tolerance.

  8. Analysis of Image Segmentation Algorithms Using MATLAB

    Deepika Khare

    2012-02-01

    Full Text Available Image segmentation has played an important role in computer vision especially for human tracking. The result of image segmentation is a set of segments that collectively cover the entire image or a set of contours extracted from the image. Its accuracy but very elusive is very crucial in areas as medical, remote sensing and image retrieval where it may contribute to save, sustain and protect human life. This paper presents the analysis and implementation using MATLAB features and one best result can be selected for any algorithm using the subjective evaluation. We considered the techniques under the following five groups: Edge-based, Clustering-based, Region-based, Threshold-based and Graph-based.

  9. Encrypting Binary Bits via Quantum Cryptography

    ZENGGuihua

    2004-01-01

    A quantum cryptographic algorithm, which may be exploited to encrypt classic information is investigated theoretically in this paper. The proposed algorithm can prevent quantum attack strategy as well as classic attack strategy. A proof-in-principle of experimental demonstration, which exploits optical fibre communication technology and photon technology, is suggested.

  10. A modified algorithm for SAR parallel imaging

    HU Ju-rong; WANG Fei; CAO Ning; LU Hao

    2009-01-01

    Synthetic aperture radar can provide two dimension images by converting the acquired echoed SAR signal to targets coordinate and reflectivity. With the advancement of sophisticated SAR signal processing, more and more SAR imaging methods have been proposed for synthetic aperture radar which works at near field and the Fresnel approximation is not appropriate. Time domain correlation is a kind of digital reconstruction method based on processing the synthetic aperture radar data in the two-dimensional frequency domain via Fourier transform. It reconstructs SAR image via simply correlation without any need for approximation or interpolation. But its high computational cost for correlation makes it unsuitable for real time imaging. In order to reduce the computational burden a modified algorithm about time domain correlation was given in this paper. It also can take full advantage of parallel computations of the imaging processor. Its practical implementation was proposed and the preliminary simulation results were presented. Simulation results show that the proposed algorithm is a computationally efficient way of implementing the reconstruction in real time SAR image processing.

  11. A Novel 1D Hybrid Chaotic Map-Based Image Compression and Encryption Using Compressed Sensing and Fibonacci-Lucas Transform

    Tongfeng Zhang

    2016-01-01

    Full Text Available A one-dimensional (1D hybrid chaotic system is constructed by three different 1D chaotic maps in parallel-then-cascade fashion. The proposed chaotic map has larger key space and exhibits better uniform distribution property in some parametric range compared with existing 1D chaotic map. Meanwhile, with the combination of compressive sensing (CS and Fibonacci-Lucas transform (FLT, a novel image compression and encryption scheme is proposed with the advantages of the 1D hybrid chaotic map. The whole encryption procedure includes compression by compressed sensing (CS, scrambling with FLT, and diffusion after linear scaling. Bernoulli measurement matrix in CS is generated by the proposed 1D hybrid chaotic map due to its excellent uniform distribution. To enhance the security and complexity, transform kernel of FLT varies in each permutation round according to the generated chaotic sequences. Further, the key streams used in the diffusion process depend on the chaotic map as well as plain image, which could resist chosen plaintext attack (CPA. Experimental results and security analyses demonstrate the validity of our scheme in terms of high security and robustness against noise attack and cropping attack.

  12. Comprehensive Infrared Image Edge detection Algorithm

    Abhishek Gudipalli

    2012-10-01

    Full Text Available Edge detection is one of the most powerful image analysis tools for enhancing and detecting edges. Indeed, identifying and localizing edges are a low level task in a variety of applications such as 3-D reconstruction, shape recognition, image compression, enhancement, and restoration. This paper introduces a new algorithm for detecting edges based on color space models. In this RGB image is taken as an input image and transforming the RGB image to color models such as YUV, YCbCr and XYZ. The edges have been detected for each component in color models separately and compared with the original image of that particular model. In order to measure the quality assessment between images, SSIM (Structural Similarity Index Method and VIF (Visual Information Fidelity has been calculated. The results have shown that XYZ color model is having high SSIM value and VIF value. In the previous papers, edge detection based on RGB color model has low SSIM and VIF values. So by converting the images into different color models shows a significant improvement in detection of edges. Keywords: Edge detection, Color models, SSIM, VIF.

  13. An improved algorithm of mask image dodging for aerial image

    Zhang, Zuxun; Zou, Songbai; Zuo, Zhiqi

    2011-12-01

    The technology of Mask image dodging based on Fourier transform is a good algorithm in removing the uneven luminance within a single image. At present, the difference method and the ratio method are the methods in common use, but they both have their own defects .For example, the difference method can keep the brightness uniformity of the whole image, but it is deficient in local contrast; meanwhile the ratio method can work better in local contrast, but sometimes it makes the dark areas of the original image too bright. In order to remove the defects of the two methods effectively, this paper on the basis of research of the two methods proposes a balance solution. Experiments show that the scheme not only can combine the advantages of the difference method and the ratio method, but also can avoid the deficiencies of the two algorithms.

  14. The Application of AES Encryption Algorithm in JAVA%AES加密算法在JAVA中的应用研究

    陈坤定

    2012-01-01

    The information security of JAVA has got attention in each industry for development technology on the web. The se- curity of the network data transmission was well improved in JAVA using AES instead of DES. Based on the development trend, the methods of the JAVA AES eccryption algorithm are relatively detailed in troduction in this paper.%JAVA作为网络上流行的开发技术,其信息的安全性已经得到各行业的重视,而AES加密算法作为替代DES的对称加密算法,在JAVA中可以很好地提高网络中数据传输的安全性.基于这个发展趋势,文章对JAVA中AES加密算法的使用方法进行较为详尽的介绍,使JAVA系统能够更好地提高数据传输和数据使用的安全性。

  15. A novel image fusion algorithm based on bandelet transform

    Xiaobo Qu; Jingwen Yan; Guofu Xie; Ziqian Zhu; Bengang Chen

    2007-01-01

    @@ A novel image fusion algorithm based on bandelet transform is proposed. Bandelet transform can take advantage of the geometrical regularity of image structure and represent sharp image transitions such as edges efficiently in image fusion.

  16. Triple Encrypted Holographic Storage and Digital Holographic System

    ZHU Yi-Chao; ZHANG Jia-Sen; GONG Qi-Huang

    2008-01-01

    We propose a triple encrypted holographic memory containing a digital holographic system. The original image is encrypted using double random phase encryption and stored in a LiNbO3:Fe crystal with shift-multiplexing. Both the reference beams of the memory and the digital holographic system are random phase encoded. We theoretically and experimentally demonstrate the encryption and decryption of multiple images and the results show high quality and good fault tolerance. The total key length of this system is larger than 4.7×1033.

  17. Triple Encrypted Holographic Storage and Digital Holographic System

    We propose a triple encrypted holographic memory containing a digital holographic system. The original image is encrypted using double random phase encryption and stored in a LiNbO3:Fe crystal with shift-multiplexing. Both the reference beams of the memory and the digital holographic system are random phase encoded. We theoretically and experimentally demonstrate the encryption and decryption of multiple images and the results show high quality and good fault tolerance. The total key length of this system is larger than 4.7 × 1033. (fundamental areas of phenomenology (including applications))

  18. A Wiener filtering based back projection algorithm for image reconstruction

    In the context of computed tomography (CT), a key techniques is the image reconstruction from projection data. The filtered back projection (FBP) algorithm is commonly used in image reconstruction. Based on cause analysis of the artifacts, we propose a new image reconstruction algorithm combining the Wiener filter and FBP algorithm. The conventional FBP image reconstruction algorithm is improved by adopting Wiener filter: and artifacts in the reconstructed images are obviously reduced. Experimental results of typical flow regimes show that the improved algorithm can effectively improve the image quality. (authors)

  19. A Novel Approach to Fast Image Filtering Algorithm of Infrared Images based on Intro Sort Algorithm

    Gupta, Kapil Kumar; Niranjan, Jitendra Kumar

    2012-01-01

    In this study we investigate the fast image filtering algorithm based on Intro sort algorithm and fast noise reduction of infrared images. Main feature of the proposed approach is that no prior knowledge of noise required. It is developed based on Stefan- Boltzmann law and the Fourier law. We also investigate the fast noise reduction approach that has advantage of less computation load. In addition, it can retain edges, details, text information even if the size of the window increases. Intro sort algorithm begins with Quick sort and switches to heap sort when the recursion depth exceeds a level based on the number of elements being sorted. This approach has the advantage of fast noise reduction by reducing the comparison time. It also significantly speed up the noise reduction process and can apply to real-time image processing. This approach will extend the Infrared images applications for medicine and video conferencing.

  20. Homomorphic Encryption: Theory & Applications

    Sen, Jaydip

    2013-01-01

    The goal of this chapter is to present a survey of homomorphic encryption techniques and their applications. After a detailed discussion on the introduction and motivation of the chapter, we present some basic concepts of cryptography. The fundamental theories of homomorphic encryption are then discussed with suitable examples. The chapter then provides a survey of some of the classical homomorphic encryption schemes existing in the current literature. Various applications and salient propert...

  1. Encryption for digital content

    Kiayias, Aggelos

    2010-01-01

    Encryption for Digital Content is an area in cryptography that is widely used in commercial productions (e.g., Blu-Ray and HD-DVDs). This book provides a comprehensive mathematical treatment of combinatorial encryption techniques used in digital content distribution systems and related attack models. A complete description of broadcast encryption with various revocation and tracing functionalities is included. ""Encryption for Digital Content"" introduces the subset cover framework (currently used in AACS, Blu-Ray and HD-DVDs,) and tracking/revocation mechanisms in various attack models. Pirat

  2. Application of MD5 Encryption Algorithm in Registration and Login Verification Module%MD5加密算法在注册及登录验证模块中的应用

    周小红; 周建伙

    2015-01-01

    With the development of Internet technology,information security is becoming more and more popular.This pa-per introduces the basic principle of the MD5 encryption algorithm.The application of MD5 encryption algorithm in the regis-tration and login verification module in the.NET environment through Visual C# is introduced in detail.The security of MD5 al-gorithm is analyzed.Final y,put forward and realize the improvement method.%随着互联网技术的发展,信息安全越来越受到人们的关注。介绍了MD5加密算法的基本原理,详细介绍如何在。 NET环境下通过Visual C#实现MD5加密算法在注册及登录验证模块中的应用。分析MD5算法的安全性,最后提出并实现自己的改进方法。

  3. Distribution of the Number of Encryptions in Revocation Schemes for Stateless Receivers

    Eagle, Christopher; Gao, Zhicheng; Omar, Mohamed; Panario, Daniel; Richmond, Bruce

    2008-01-01

    International audience We study the number of encryptions necessary to revoke a set of users in the complete subtree scheme (CST) and the subset-difference scheme (SD). These are well-known tree based broadcast encryption schemes. Park and Blake in: Journal of Discrete Algorithms, vol. 4, 2006, pp. 215―238, give the mean number of encryptions for these schemes. We continue their analysis and show that the limiting distribution of the number of encryptions for these schemes is normal. This ...

  4. Face Protection by Fast Selective Encryption in a Video

    Rodrigues, José; Puech, William; Meuel, Peter; Bajard, Jean-Claude; Chaumont, Marc

    2006-01-01

    International audience In this paper we propose an approach for monitoring human activities in an indoor environment using detected and tracked face and selective encryption. The objective is to encrypt partially the human face in a video sequence. This approach is based on AES stream ciphering using VLC (Variable Length Coding) of the Huffman's vector. The proposed scheme allows scalable decryption of a specific region of image and result in a significant reduction in encrypting and decry...

  5. Digital image encryption method of dual randomized phase Fresnel diffraction based on CGH%基于计算全息的菲涅尔双随机相位加密技术

    于娜娜

    2012-01-01

    基于傅里叶计算全息技术,结合菲涅尔双随机相位加密系统,提出了一种数字图像加密方法。该方法以傅里叶计算全息图记录菲涅尔衍射双随机相位加密图像,傅里叶计算全息加密图像隐藏了原图像大小尺度信息,而且再现多个图像,必须针对加密图像共轭方可解密,提高了图像加密的安全性,并且解决了普通方法加密图像难存储的问题,作为原始明文的拥有者,两个随机相位板,应用波长,两次菲涅尔衍射的距离都可作为解密密钥。%A new method of digital image encryption using Fourier CGH,combined the Fresnel dual randomized phase encryption system is proposed.In this method the encryption images of Fresnel diffraction two random phases system is recorded by Fourier CGH,The Fourier CGH is an image without size scale information of the original image and many images representation,but the decryption must according to the conjugate of original encryption,so this method greatly enhances the image encryption security.As the owner of the original image,three phase plate,application wavelength,twice the distance of the Fresnel diffraction can serve as decryption keys.

  6. Segmentation of Medical Image using Clustering and Watershed Algorithms

    M. C.J. Christ; R. M. S. Parvathi

    2011-01-01

    Problem statement: Segmentation plays an important role in medical imaging. Segmentation of an image is the division or separation of the image into dissimilar regions of similar attribute. In this study we proposed a methodology that integrates clustering algorithm and marker controlled watershed segmentation algorithm for medical image segmentation. The use of the conservative watershed algorithm for medical image analysis is pervasive because of its advantages, such as always being able to...

  7. Relaxation Algorithm of Piecing-Error for Sub-Images

    LI Yueping; TANG Pushan

    2001-01-01

    During the process of automatic image recognition or automatic reverse design of IC, people often encounter the problem that some sub-images must be pieced together into a whole image. In the traditional piecing algorithm for sub images, a large accumulated error will be made. In this paper, a relaxation algorithm of piecing-error for sub-images is presented. It can eliminate the accumulated error in the traditional algorithm and greatly improve the quality of pieced image. Based on an initial pieced image, one can continuously adjust the center of every sub-image and its angle to lessen the error between the adjacent sub-images, so the quality of pieced image can be improved. The presented results indicate that the proposed algorithm can dramatically decrease the error while the quality of ultimate pieced image is still acceptable. The time complexity of this algorithm is O(n In n).

  8. Digital Image Mosaic Technology Based on Improved Genetic Algorithm

    Li Yan

    2014-03-01

    Full Text Available Image mosaic technology is an important technology in the field of image processing. Based on the general adaptability and clustering of genetic algorithm, we improve it, and apply it to the mosaic algorithm in image processing. In this paper, we test the validity and reliability of the designed algorithm in the process of image mosaic algorithm. Based on the image illumination mosaic and painting texture mosaic image we achieve certain artistic effect. From the convergence results of general algorithm, the results of numerical show substantially concussion, oscillation amplitude reaches a maximum of . The calculation results of the genetic algorithm still have certain degree of concussion, oscillation amplitude reaches a maximum of , convergence results are slightly better than the general algorithm. The improved genetic algorithm results have no concussion, the stability is very good, and the results have better astringency.

  9. Algorithms evaluation for fundus images enhancement

    Color images of the retina inherently involve noise and illumination artifacts. In order to improve the diagnostic quality of the images, it is desirable to homogenize the non-uniform illumination and increase contrast while preserving color characteristics. The visual result of different pre-processing techniques can be very dissimilar and it is necessary to make an objective assessment of the techniques in order to select the most suitable. In this article the performance of eight algorithms to correct the non-uniform illumination, contrast modification and color preservation was evaluated. In order to choose the most suitable a general score was proposed. The results got good impression from experts, although some differences suggest that not necessarily the best statistical quality of image is the one of best diagnostic quality to the trained doctor eye. This means that the best pre-processing algorithm for an automatic classification may be different to the most suitable one for visual diagnosis. However, both should result in the same final diagnosis.

  10. Interactive Evolutionary Algorithms for Image Enhancement and Creation

    Mist, Joseph James

    2014-01-01

    Image enhancement and creation, particularly for aesthetic purposes, are tasks for which the use of interactive evolutionary algorithms would seem to be well suited. Previous work has concentrated on the development of various aspects of the interactive evolutionary algorithms and their application to various image enhancement and creation problems. Robust evaluation of algorithmic design options in interactive evolutionary algorithms and the comparison of interactive evolutionary algorithms ...

  11. An adaptive algorithm for low contrast infrared image enhancement

    Liu, Sheng-dong; Peng, Cheng-yuan; Wang, Ming-jia; Wu, Zhi-guo; Liu, Jia-qi

    2013-08-01

    An adaptive infrared image enhancement algorithm for low contrast is proposed in this paper, to deal with the problem that conventional image enhancement algorithm is not able to effective identify the interesting region when dynamic range is large in image. This algorithm begin with the human visual perception characteristics, take account of the global adaptive image enhancement and local feature boost, not only the contrast of image is raised, but also the texture of picture is more distinct. Firstly, the global image dynamic range is adjusted from the overall, the dynamic range of original image and display grayscale form corresponding relationship, the gray scale of bright object is raised and the the gray scale of dark target is reduced at the same time, to improve the overall image contrast. Secondly, the corresponding filtering algorithm is used on the current point and its neighborhood pixels to extract image texture information, to adjust the brightness of the current point in order to enhance the local contrast of the image. The algorithm overcomes the default that the outline is easy to vague in traditional edge detection algorithm, and ensure the distinctness of texture detail in image enhancement. Lastly, we normalize the global luminance adjustment image and the local brightness adjustment image, to ensure a smooth transition of image details. A lot of experiments is made to compare the algorithm proposed in this paper with other convention image enhancement algorithm, and two groups of vague IR image are taken in experiment. Experiments show that: the contrast ratio of the picture is boosted after handled by histogram equalization algorithm, but the detail of the picture is not clear, the detail of the picture can be distinguished after handled by the Retinex algorithm. The image after deal with by self-adaptive enhancement algorithm proposed in this paper becomes clear in details, and the image contrast is markedly improved in compared with Retinex

  12. A complete classification of quantum public-key encryption protocols

    Wu, Chenmiao; Yang, Li

    2015-10-01

    We present a classification of quantum public-key encryption protocols. There are six elements in quantum public-key encryption: plaintext, ciphertext, public-key, private-key, encryption algorithm and decryption algorithm. According to the property of each element which is either quantum or classical, the quantum public-key encryption protocols can be divided into 64 kinds. Among 64 kinds of protocols, 8 kinds have already been constructed, 52 kinds can be proved to be impossible to construct and the remaining 4 kinds have not been presented effectively yet. This indicates that the research on quantum public-key encryption protocol should be focus on the existed kinds and the unproposed kinds.

  13. Evaluation of various deformable image registration algorithms for thoracic images

    We evaluated the accuracy of one commercially available and three publicly available deformable image registration (DIR) algorithms for thoracic four-dimensional (4D) computed tomography (CT) images. Five patients with esophagus cancer were studied. Datasets of the five patients were provided by DIR-lab (dir-lab.com) and consisted of thoracic 4D CT images and a coordinate list of anatomical landmarks that had been manually identified. Expert landmark correspondence was used for evaluating DIR spatial accuracy. First, the manually measured displacement vector field (mDVF) was obtained from the coordinate list of anatomical landmarks. Then the automatically calculated displacement vector field (aDVF) was calculated by using the following four DIR algorithms: B-spine implemented in Velocity AI (Velocity Medical, Atlanta, GA, USA), free-form deformation (FFD), Horn–Schunk optical flow (OF) and Demons in DIRART of MATLAB software. Registration error is defined as the difference between mDVF and aDVF. The mean 3D registration errors were 2.7 ± 0.8 mm for B-spline, 3.6 ± 1.0 mm for FFD, 2.4 ± 0.9 mm for OF and 2.4 ± 1.2 mm for Demons. The results showed that reasonable accuracy was achieved in B-spline, OF and Demons, and that these algorithms have the potential to be used for 4D dose calculation, automatic image segmentation and 4D CT ventilation imaging in patients with thoracic cancer. However, for all algorithms, the accuracy might be improved by using the optimized parameter setting. Furthermore, for B-spline in Velocity AI, the 3D registration error was small with displacements of less than ∼10 mm, indicating that this software may be useful in this range of displacements

  14. The Watershed Algorithm for Image Segmentation

    OU Yan; LIN Nan

    2007-01-01

    This article introduced the watershed algorithm for the segmentation, illustrated the segmation process by implementing this algorithm. By comparing with another three related algorithm, this article revealed both the advantages and drawbacks of the watershed algorithm.

  15. A new semi-fragile watermarking algorithm for image authentication

    HAN De-zhi; HU Yu-ping

    2005-01-01

    This paper presents a new semi-fragile watermarking algorithm for image authentication which extracts image features from the low frequency domain to generate two watermarks: one for classifying of the intentional content modification and the other for indicating the modified location. The algorithm provides an effective mechanism for image authentication. The watermark generation and watermark embedment are disposed in the image itself, and the received image authentication needs no information about the original image or watermark. The algorithm increases watermark security and prevents forged watermark. Experimental results show that the algorithm can identify intentional content modification and incidental tampering, and also indicate the location where a modification takes place.

  16. Relaxation Algorithm of Piecing—Error for Sub—Images

    李跃平; 唐璞山

    2001-01-01

    During the process of automatic image recognition or automatic reverse design of IC,people often encounter the problem that some sub-images must be pieced together into a whole image,In the traditional piecing algorithm for subimages,a large accumulated error will be made.In this paper,a relaxation algorithm of piecing -error for sub-images is presented.It can eliminate the accumulated error in the traditional algorithm and greatly improve the quality of pieced image.Based on an initial pieced image,one can continuously adjust the center of every sub-image and its angle to lessen the error between the adjacent sub-images,so the quality of pieced image can be improved.The presented results indicate that the proposed algorithm can dramatically decrease the error while the quality of ultimate pieced image is still acceptable.The time complexity of this algorithm is O(nlnn).

  17. Improved bat algorithm applied to multilevel image thresholding.

    Alihodzic, Adis; Tuba, Milan

    2014-01-01

    Multilevel image thresholding is a very important image processing technique that is used as a basis for image segmentation and further higher level processing. However, the required computational time for exhaustive search grows exponentially with the number of desired thresholds. Swarm intelligence metaheuristics are well known as successful and efficient optimization methods for intractable problems. In this paper, we adjusted one of the latest swarm intelligence algorithms, the bat algorithm, for the multilevel image thresholding problem. The results of testing on standard benchmark images show that the bat algorithm is comparable with other state-of-the-art algorithms. We improved standard bat algorithm, where our modifications add some elements from the differential evolution and from the artificial bee colony algorithm. Our new proposed improved bat algorithm proved to be better than five other state-of-the-art algorithms, improving quality of results in all cases and significantly improving convergence speed. PMID:25165733

  18. Improved Bat Algorithm Applied to Multilevel Image Thresholding

    Adis Alihodzic

    2014-01-01

    Full Text Available Multilevel image thresholding is a very important image processing technique that is used as a basis for image segmentation and further higher level processing. However, the required computational time for exhaustive search grows exponentially with the number of desired thresholds. Swarm intelligence metaheuristics are well known as successful and efficient optimization methods for intractable problems. In this paper, we adjusted one of the latest swarm intelligence algorithms, the bat algorithm, for the multilevel image thresholding problem. The results of testing on standard benchmark images show that the bat algorithm is comparable with other state-of-the-art algorithms. We improved standard bat algorithm, where our modifications add some elements from the differential evolution and from the artificial bee colony algorithm. Our new proposed improved bat algorithm proved to be better than five other state-of-the-art algorithms, improving quality of results in all cases and significantly improving convergence speed.

  19. The application and implementatio of MD5 encryption algorithm in the anthentication of the user management system based on LDAP%MD5算法在统一用户管理系统中身份认证的应用

    郑之华

    2012-01-01

    This paper describes the MD5 encryption algorithm and its working principle, puts forward the application and implementatio of MD5 encryption algorithm in the anthentication of the user management system based on LDAP, and suggestions for improvement ideas.%介绍了MD5加密算法及其工作原理,提出了MD5在基于LDAP的统一用户管理系统中身份认证的应用和实现,并提出了改进思想。

  20. Performance Comparison Of Evolutionary Algorithms For Image Clustering

    Civicioglu, P.; Atasever, U. H.; Ozkan, C.; Besdok, E.; Karkinli, A. E.; Kesikoglu, A.

    2014-09-01

    Evolutionary computation tools are able to process real valued numerical sets in order to extract suboptimal solution of designed problem. Data clustering algorithms have been intensively used for image segmentation in remote sensing applications. Despite of wide usage of evolutionary algorithms on data clustering, their clustering performances have been scarcely studied by using clustering validation indexes. In this paper, the recently proposed evolutionary algorithms (i.e., Artificial Bee Colony Algorithm (ABC), Gravitational Search Algorithm (GSA), Cuckoo Search Algorithm (CS), Adaptive Differential Evolution Algorithm (JADE), Differential Search Algorithm (DSA) and Backtracking Search Optimization Algorithm (BSA)) and some classical image clustering techniques (i.e., k-means, fcm, som networks) have been used to cluster images and their performances have been compared by using four clustering validation indexes. Experimental test results exposed that evolutionary algorithms give more reliable cluster-centers than classical clustering techniques, but their convergence time is quite long.