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Sample records for image encryption algorithm

  1. Wavelet Image Encryption Algorithm Based on AES

    Institute of Scientific and Technical Information of China (English)

    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

    OpenAIRE

    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

    Directory of Open Access Journals (Sweden)

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

    OpenAIRE

    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...

  5. ALGORITHM FOR IMAGE MIXING AND ENCRYPTION

    Directory of Open Access Journals (Sweden)

    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.

  6. Novel permutation measures for image encryption algorithms

    Science.gov (United States)

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

    2016-10-01

    This paper proposes two measures for the evaluation of permutation techniques used in image encryption. First, a general mathematical framework for describing the permutation phase used in image encryption is presented. Using this framework, six different permutation techniques, based on chaotic and non-chaotic generators, are described. The two new measures are, then, introduced to evaluate the effectiveness of permutation techniques. These measures are (1) Percentage of Adjacent Pixels Count (PAPC) and (2) Distance Between Adjacent Pixels (DBAP). The proposed measures are used to evaluate and compare the six permutation techniques in different scenarios. The permutation techniques are applied on several standard images and the resulting scrambled images are analyzed. Moreover, the new measures are used to compare the permutation algorithms on different matrix sizes irrespective of the actual parameters used in each algorithm. The analysis results show that the proposed measures are good indicators of the effectiveness of the permutation technique.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Meteosat Images Encryption based on AES and RSA Algorithms

    Directory of Open Access Journals (Sweden)

    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

    OpenAIRE

    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

    Directory of Open Access Journals (Sweden)

    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 a communication perspective

    CERN Document Server

    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,

  13. Image Encryption Algorithm Based on Chaotic Economic Model

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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. A novel image encryption algorithm based on DNA subsequence operation.

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Qiang Zhang

    2012-01-01

    Full Text Available 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.

  17. A New Reversible Date-Hiding Algorithm for Encrypted Images

    Directory of Open Access Journals (Sweden)

    Laicheng Cao

    2016-01-01

    Full Text Available In order to effectively increase embedding capacity and completely extract the watermarking information in information hiding of encrypted images, a new reversible watermarking embedding algorithm based on rhombus prediction model and difference histogram shifting ideas is proposed. Firstly, the images are pretreated according to rhombus prediction model. Then, the watermarking information is embedded in encrypted images by effective combination of homomorphism encryption scheme and reversible watermarking techniques. Finally, the watermarking information is completely extracted and the images are recovered based on computed difference histogram from left to right and from top to bottom. So, the efficiency and reversibility are ensured when watermarking information is embedded in encrypted image. Experiment results show that the proposed algorithm is simple and easy to realize, the embedding capacity is effectively increased, watermarking information is completely reversible, and the image can be recovered with no distortion.

  18. Design and Implementation of Image Encryption Algorithm Using Chaos

    Directory of Open Access Journals (Sweden)

    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.

  19. Digital Image Encryption Algorithm Design Based on Genetic Hyperchaos

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    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...

  1. Image Encryption Algorithm Based on Chaotic Economic Model

    OpenAIRE

    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...

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

    Science.gov (United States)

    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

  3. Grayscale image encryption algorithm based on chaotic maps

    Institute of Scientific and Technical Information of China (English)

    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.

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

    OpenAIRE

    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-...

  5. Chaotic Image Encryption Algorithm by Correlating Keys with Plaintext

    Institute of Scientific and Technical Information of China (English)

    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.

  6. Design and Implementation of Image Encryption Algorithm Using Chaos

    OpenAIRE

    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...

  7. Chaos-Based Image Encryption Algorithm Using Decomposition

    OpenAIRE

    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. ...

  8. Analyzing the Efficiency of Text-to-Image Encryption Algorithm

    Directory of Open Access Journals (Sweden)

    Ahmad Abusukhon

    2012-12-01

    Full Text Available Today many of the activities are performed online through the Internet. One of the methods used to protect the data while sending it through the Internet is cryptography. In a previous work we proposed the Text-to-Image Encryption algorithm (TTIE as a novel algorithm for network security. In this paper we investigate the efficiency of (TTIE for large scale collection.

  9. An Uncompressed Image Encryption Algorithm Based on DNA Sequences

    Directory of Open Access Journals (Sweden)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    OpenAIRE

    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 ...

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  14. A Novel Algorithm for Watermarking and Image Encryption

    Directory of Open Access Journals (Sweden)

    Rakesh S

    2012-01-01

    Full Text Available Digital watermarking is a method of copyright protection of audio, images, video and text. We propose a new robust watermarking technique based on contourlet transform and singular value decomposition. The paper also proposes a novel encryption algorithm to store a signed double matrix as an RGB image. The entropy of the watermarked image and correlation coefficient of extracted watermark image is very close to ideal values, proving the correctness of proposed algorithm. Also experimental results show resiliency of the scheme against large blurring attack like mean and gaussian filtering, linear filtering (high pass and low pass filtering , non-linear filtering (median filtering, addition of a constant offset to the pixel values and local exchange of pixels .Thus proving the security, effectiveness and robustness of the proposed watermarking algorithm.

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

    Science.gov (United States)

    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

  16. An improved image encryption algorithm based on chaotic maps

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. A fast image encryption algorithm based on chaotic map

    Science.gov (United States)

    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.

  19. A joint watermarking/encryption algorithm for verifying medical image integrity and authenticity in both encrypted and spatial domains.

    Science.gov (United States)

    Bouslimi, D; Coatrieux, G; Roux, Ch

    2011-01-01

    In this paper, we propose a new joint watermarking/encryption algorithm for the purpose of verifying the reliability of medical images in both encrypted and spatial domains. It combines a substitutive watermarking algorithm, the quantization index modulation (QIM), with a block cipher algorithm, the Advanced Encryption Standard (AES), in CBC mode of operation. The proposed solution gives access to the outcomes of the image integrity and of its origins even though the image is stored encrypted. Experimental results achieved on 8 bits encoded Ultrasound images illustrate the overall performances of the proposed scheme. By making use of the AES block cipher in CBC mode, the proposed solution is compliant with or transparent to the DICOM standard.

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

    Science.gov (United States)

    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.

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

    OpenAIRE

    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...

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    OpenAIRE

    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,...

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

    International Nuclear Information System (INIS)

    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)

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    OpenAIRE

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Double images encryption method with resistance against the specific attack based on an asymmetric algorithm.

    Science.gov (United States)

    Wang, Xiaogang; Zhao, Daomu

    2012-05-21

    A double-image encryption technique that based on an asymmetric algorithm is proposed. In this method, the encryption process is different from the decryption and the encrypting keys are also different from the decrypting keys. In the nonlinear encryption process, the images are encoded into an amplitude cyphertext, and two phase-only masks (POMs) generated based on phase truncation are kept as keys for decryption. By using the classical double random phase encoding (DRPE) system, the primary images can be collected by an intensity detector that located at the output plane. Three random POMs that applied in the asymmetric encryption can be safely applied as public keys. Simulation results are presented to demonstrate the validity and security of the proposed protocol.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Optical multiple-image encryption based on phase encoding algorithm in the Fresnel transform domain

    Science.gov (United States)

    Huang, Jian-Ji; Hwang, Hone-Ene; Chen, Chun-Yuan; Chen, Ching-Mu

    2012-10-01

    A novel method of the optical multiple-image encryption based on the modified Gerchberg-Saxton algorithm (MGSA) is presented. This proposed method with an architecture of two adjacent phase only functions (POFs) in the Fresnel transform (FrT) domain that can extremely increase capacity of system for completely avoiding the crosstalk between the decrypted images. Each encrypted target image is separately encoded into a POF by using the MGSA which is with constraining the encrypted target image. Each created POF is then added to a prescribed fixed POF composed of a proposed MGSA-based phase encoding algorithm. Not only the wavelength and multiple-position parameters in the FrT domain as keys to increase system security, the created POFs are also served mutually as the encryption keys to decrypt target image based on cascading two POFs scheme. Compared with prior methods [23,24], the main advantages of this proposed encryption system is that it does not need any transformative lenses and that makes it very efficient and easy to implement optically. Simulation results show that this proposed encryption system can successfully achieve the multiple-image encryption with multiple-position keys, which is more advantageous in security than previous work [24] for its decryption process with only two POFs keys to accomplish this task.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  19. A Brief Study of Video Encryption Algorithms

    Directory of Open Access Journals (Sweden)

    Pranali Pasalkar,

    2015-02-01

    Full Text Available Video is a set of images .Video encryption is encrypting those set of images .Thus video encryption is simply hiding your video from prying eyes .Video monitoring has always been in concerned .Multimedia security is very important for multimedia commerce on Internet such as video on demand and Real time video multicast. There are various video encryption algorithm. All have some kind of weakness .In this paper classification of various existing algorithm, its advantages and disadvantages is discussed.

  20. Image encryption in the wavelet domain

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  3. Optical image encryption topology.

    Science.gov (United States)

    Yong-Liang, Xiao; Xin, Zhou; Qiong-Hua, Wang; Sheng, Yuan; Yao-Yao, Chen

    2009-10-15

    Optical image encryption topology is proposed based on the principle of random-phase encoding. Various encryption topological units, involving peer-to-peer, ring, star, and tree topologies, can be realized by an optical 6f system. These topological units can be interconnected to constitute an optical image encryption network. The encryption and decryption can be performed in both digital and optical methods.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  5. A joint encryption/watermarking algorithm for verifying the reliability of medical images: application to echographic images.

    Science.gov (United States)

    Bouslimi, Dalel; Coatrieux, Gouenou; Roux, Christian

    2012-04-01

    In this paper we propose a joint encryption/watermarking algorithm for the purpose of protecting medical images. The proposed solution gives access to the outcomes of the image integrity and of its origins as its attachment to one patient even if the image is stored encrypted. In this study, the given solution combines the RC4 stream cipher and two substitutive watermarking modulations: the Least Significant Bit Method and the Quantization Index Modulation. If watermarking and encryption are conducted jointly at the protection stage, watermark extraction and decryption can be applied independently. Experimental results achieved on 8 bits encoded echographic images illustrate the overall performances of the proposed scheme. At least, a capacity rate of 1 and 0.5 bits of message per pixel of image can be embedded in the spatial and the encrypted domains respectively, with a peak signal to noise ratio greater than 49 dB.

  6. A novel image encryption algorithm based on chaos maps with Markov properties

    Science.gov (United States)

    Liu, Quan; Li, Pei-yue; Zhang, Ming-chao; Sui, Yong-xin; Yang, Huai-jiang

    2015-02-01

    In order to construct high complexity, secure and low cost image encryption algorithm, a class of chaos with Markov properties was researched and such algorithm was also proposed. The kind of chaos has higher complexity than the Logistic map and Tent map, which keeps the uniformity and low autocorrelation. An improved couple map lattice based on the chaos with Markov properties is also employed to cover the phase space of the chaos and enlarge the key space, which has better performance than the original one. A novel image encryption algorithm is constructed on the new couple map lattice, which is used as a key stream generator. A true random number is used to disturb the key which can dynamically change the permutation matrix and the key stream. From the experiments, it is known that the key stream can pass SP800-22 test. The novel image encryption can resist CPA and CCA attack and differential attack. The algorithm is sensitive to the initial key and can change the distribution the pixel values of the image. The correlation of the adjacent pixels can also be eliminated. When compared with the algorithm based on Logistic map, it has higher complexity and better uniformity, which is nearer to the true random number. It is also efficient to realize which showed its value in common use.

  7. Reversible Data Hiding In Encrypted Images Using Improved Encryption Technique

    Directory of Open Access Journals (Sweden)

    Balika J. Chelliah

    2015-11-01

    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 some errors on data extraction and/or image restoration. In this paper we propose a different scheme which attains real reversibility by reserving room before encryption with a traditional RDH algorithm, and then encrypting the data and embedding the data in the encrypted image, which is encrypted using a new proposed algorithm. The proposed method can achieve real reversibility that is data extraction and image recoveries are free of any error.

  8. Reversible Data Hiding In Encrypted Images Using Improved Encryption Technique

    Directory of Open Access Journals (Sweden)

    Mr. Balika J. Chelliah

    2014-03-01

    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 some errors on data extraction and/or image restoration. In this paper we propose a different scheme which attains real reversibility by reserving room before encryption with a traditional RDH algorithm, and then encrypting the data and embedding the data in the encrypted image, which is encrypted using a new proposed algorithm. The proposed method can achieve real reversibility that is data extraction and image recoveries are free of any error.

  9. New color image encryption algorithm based on compound chaos mapping and hyperchaotic cellular neural network

    Science.gov (United States)

    Li, Jinqing; Bai, Fengming; Di, Xiaoqiang

    2013-01-01

    We propose an image encryption/decryption algorithm based on chaotic control parameter and hyperchaotic system with the composite permutation-diffusion structure. Compound chaos mapping is used to generate control parameters in the permutation stage. The high correlation between pixels is shuffled. In the diffusion stage, compound chaos mapping of different initial condition and control parameter generates the diffusion parameters, which are applied to hyperchaotic cellular neural networks. The diffusion key stream is obtained by this process and implements the pixels' diffusion. Compared with the existing methods, both simulation and statistical analysis of our proposed algorithm show that the algorithm has a good performance against attacks and meets the corresponding security level.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  12. Image encryption algorithm based on wavelet packet decomposition and discrete linear canonical transform

    Science.gov (United States)

    Sharma, K. K.; Jain, Heena

    2013-01-01

    The security of digital data including images has attracted more attention recently, and many different image encryption methods have been proposed in the literature for this purpose. In this paper, a new image encryption method using wavelet packet decomposition and discrete linear canonical transform is proposed. The use of wavelet packet decomposition and DLCT increases the key size significantly making the encryption more robust. Simulation results of the proposed technique are also presented.

  13. A novel image encryption algorithm using chaos and reversible cellular automata

    Science.gov (United States)

    Wang, Xingyuan; Luan, Dapeng

    2013-11-01

    In this paper, a novel image encryption scheme is proposed based on reversible cellular automata (RCA) combining chaos. In this algorithm, an intertwining logistic map with complex behavior and periodic boundary reversible cellular automata are used. We split each pixel of image into units of 4 bits, then adopt pseudorandom key stream generated by the intertwining logistic map to permute these units in confusion stage. And in diffusion stage, two-dimensional reversible cellular automata which are discrete dynamical systems are applied to iterate many rounds to achieve diffusion on bit-level, in which we only consider the higher 4 bits in a pixel because the higher 4 bits carry almost the information of an image. Theoretical analysis and experimental results demonstrate the proposed algorithm achieves a high security level and processes good performance against common attacks like differential attack and statistical attack. This algorithm belongs to the class of symmetric systems.

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

    OpenAIRE

    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...

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

    Science.gov (United States)

    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.

  16. A joint image encryption and watermarking algorithm based on compressive sensing and chaotic map

    Science.gov (United States)

    Xiao, Di; Cai, Hong-Kun; Zheng, Hong-Ying

    2015-06-01

    In this paper, a compressive sensing (CS) and chaotic map-based joint image encryption and watermarking algorithm is proposed. The transform domain coefficients of the original image are scrambled by Arnold map firstly. Then the watermark is adhered to the scrambled data. By compressive sensing, a set of watermarked measurements is obtained as the watermarked cipher image. In this algorithm, watermark embedding and data compression can be performed without knowing the original image; similarly, watermark extraction will not interfere with decryption. Due to the characteristics of CS, this algorithm features compressible cipher image size, flexible watermark capacity, and lossless watermark extraction from the compressed cipher image as well as robustness against packet loss. Simulation results and analyses show that the algorithm achieves good performance in the sense of security, watermark capacity, extraction accuracy, reconstruction, robustness, etc. Project supported by the Open Research Fund of Chongqing Key Laboratory of Emergency Communications, China (Grant No. CQKLEC, 20140504), the National Natural Science Foundation of China (Grant Nos. 61173178, 61302161, and 61472464), and the Fundamental Research Funds for the Central Universities, China (Grant Nos. 106112013CDJZR180005 and 106112014CDJZR185501).

  17. Optical image encryption based on diffractive imaging.

    Science.gov (United States)

    Chen, Wen; Chen, Xudong; Sheppard, Colin J R

    2010-11-15

    In this Letter, we propose a method for optical image encryption based on diffractive imaging. An optical multiple random phase mask encoding system is applied, and one of the phase-only masks is selected and laterally translated along a preset direction during the encryption process. For image decryption, a phase retrieval algorithm is proposed to extract a high-quality plaintext. The feasibility and effectiveness of the proposed method are demonstrated by numerical results. The proposed method can provide a new strategy instead of conventional interference methods, and it may open up a new research perspective for optical image encryption.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Science.gov (United States)

    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

  20. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  1. A novel color image encryption algorithm based on genetic recombination and the four-dimensional memristive hyperchaotic system

    Science.gov (United States)

    Chai, Xiu-Li; Gan, Zhi-Hua; Lu, Yang; Zhang, Miao-Hui; Chen, Yi-Ran

    2016-10-01

    Recently, many image encryption algorithms based on chaos have been proposed. Most of the previous algorithms encrypt components R, G, and B of color images independently and neglect the high correlation between them. In the paper, a novel color image encryption algorithm is introduced. The 24 bit planes of components R, G, and B of the color plain image are obtained and recombined into 4 compound bit planes, and this can make the three components affect each other. A four-dimensional (4D) memristive hyperchaotic system generates the pseudorandom key streams and its initial values come from the SHA 256 hash value of the color plain image. The compound bit planes and key streams are confused according to the principles of genetic recombination, then confusion and diffusion as a union are applied to the bit planes, and the color cipher image is obtained. Experimental results and security analyses demonstrate that the proposed algorithm is secure and effective so that it may be adopted for secure communication. Project supported by the National Natural Science Foundation of China (Grant Nos. 61203094 and 61305042), the Natural Science Foundation of the United States (Grant Nos. CNS-1253424 and ECCS-1202225), the Science and Technology Foundation of Henan Province, China (Grant No. 152102210048), the Foundation and Frontier Project of Henan Province, China (Grant No. 162300410196), the Natural Science Foundation of Educational Committee of Henan Province, China (Grant No. 14A413015), and the Research Foundation of Henan University, China (Grant No. xxjc20140006).

  2. 3D Chaotic Functions for Image Encryption

    Directory of Open Access Journals (Sweden)

    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.

  3. Stream Deniable-Encryption Algorithms

    Directory of Open Access Journals (Sweden)

    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.

  4. Multilevel Image Encryption

    OpenAIRE

    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...

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

    Institute of Scientific and Technical Information of China (English)

    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.

  6. IMAGE ENCRYPTION BASED ON SINGULAR VALUE DECOMPOSITION

    Directory of Open Access Journals (Sweden)

    Nidhal K. El Abbadi

    2014-01-01

    Full Text Available Image encryption is one of the most methods of information hiding. A novel secure encryption method for image encryption is presented in this study. The proposed algorithm based on using singular value decomposition SVD. In this study we start to scramble the image data according to suggested keys (two sequence scrambling process with two different keys to finally create two different matrices. The diagonal matrix from the SVD will be interchanged with the resulted matrices. Another scrambling and diagonal matrices interchange will apply to increase the complexity. The resulted two matrices combine to one matrix according to predefined procedure. The encrypted image is a meaningfull image. The suggested method tested with many images encryption and gives promised results.

  7. Spatial chaos-based image encryption design

    Institute of Scientific and Technical Information of China (English)

    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.

  8. Spatial chaos-based image encryption design

    Institute of Scientific and Technical Information of China (English)

    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.

  9. Advanced Steganography Algorithm using Encrypted secret message

    Directory of Open Access Journals (Sweden)

    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.

  10. Image encryption using the fractional wavelet transform

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. Image encryption using the fractional wavelet transform

    International Nuclear Information System (INIS)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  14. Multiple image encryption by phase retrieval

    Science.gov (United States)

    Di, Hong; Kang, Yanmei; Liu, Yueqin; Zhang, Xin

    2016-07-01

    Multiple image encryption (MIE) was proposed to increase the efficiency of encrypting images by processing several images simultaneously. Because of the advantage of optical technology in processing twodimensional images at high throughput, MIE has been significantly improved by use of methods originating from optics. Phase retrieval was the process of algorithmically finding solutions to the phase loss problem due to light detectors only capturing the intensity. It was to retrieve phase information for the determination of a structure from diffraction data. Error-reduction algorithm is a typical phase retrieval method. Here, we employ it to illustrate that methods in phase retrieval are able to encrypt multiple images and compress them into encrypted data simultaneously. Moreover, the decryption is also designed to handle multiple images at the same time. The whole process including both the encryption and decryption is proposed to improve MIE with respect to the compression and efficiency. The feasibility and encryption of the MIE scheme is demonstrated with encryption experiments under Gaussian white noise and unauthorized access.

  15. Selective image encryption using a spatiotemporal chaotic system.

    Science.gov (United States)

    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

  16. 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

    Institute of Scientific and Technical Information of China (English)

    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。

  17. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  18. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  19. Dual encryption scheme of images using polarized light.

    Science.gov (United States)

    Alfalou, A; Brosseau, C

    2010-07-01

    We propose and analyze a dual encryption/decryption scheme, motivated by recent interest in polarization encoding. Compared to standard optical encryption methods, which are based on phase and amplitude manipulation, this encryption procedure relying on Mueller-Stokes formalism provides large flexibility in the key encryption design. The effectiveness of our algorithm is discussed, thanks to a numerical simulation of the polarization encryption/decryption procedure of a 256 gray-level image. Of additional special interest is the immunity of this encryption algorithm to brute force attacks.

  20. 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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  3. Optical image encryption based on multifractional Fourier transforms.

    Science.gov (United States)

    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

  4. Digital Image Encryption Scheme Based on Multiple Chaotic Systems

    Science.gov (United States)

    Abd El-Latif, Ahmed A.; Li, Li; Zhang, Tiejun; Wang, Ning; Song, Xianhua; Niu, Xiamu

    2012-06-01

    Image encryption is a challenging task due to the significant level of sophistication achieved by forgerers and other cybercriminals. Advanced encryption methods for secure transmission, storage, and retrieval of digital images are increasingly needed for a number of military, medical, homeland security, and other applications. In this paper, we introduce a new digital image encryption algorithm. The new algorithm employs multiple chaotic systems and cryptographic primitive operations within the encryption process, which are efficiently implemented on modern processors, and adopts round keys for encryption using a chaotic map. Experiments conducted show that the proposed algorithm possesses robust security features such as fairly uniform distribution, high sensitivity to both keys and plainimages, almost ideal entropy, and the ability to highly de-correlate adjacent pixels in the cipherimages. Furthermore, it has a large key space, which greatly increases its security for image encryption applications.

  5. Image encryption using high-dimension chaotic system

    Institute of Scientific and Technical Information of China (English)

    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.

  6. A realizable quantum encryption algorithm for qubits

    Institute of Scientific and Technical Information of China (English)

    Zhou Nan-Run; Zeng Gui-Hua

    2005-01-01

    A realizable quantum encryption algorithm for qubits is presented by employing bit-wise quantum computation.System extension and bit-swapping are introduced into the encryption process, which makes the ciphertext space expanded greatly. The security of the proposed algorithm is analysed in detail and the schematic physical implementation is also provided. It is shown that the algorithm, which can prevent quantum attack strategy as well as classical attack strategy, is effective to protect qubits. Finally, we extend our algorithm to encrypt classical binary bits and quantum entanglements.

  7. Securing Images Using Chaotic-based Image Encryption Cryptosystem

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    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. Optical image encryption using multilevel Arnold transform and noninterferometric imaging

    Science.gov (United States)

    Chen, Wen; Chen, Xudong

    2011-11-01

    Information security has attracted much current attention due to the rapid development of modern technologies, such as computer and internet. We propose a novel method for optical image encryption using multilevel Arnold transform and rotatable-phase-mask noninterferometric imaging. An optical image encryption scheme is developed in the gyrator transform domain, and one phase-only mask (i.e., phase grating) is rotated and updated during image encryption. For the decryption, an iterative retrieval algorithm is proposed to extract high-quality plaintexts. Conventional encoding methods (such as digital holography) have been proven vulnerably to the attacks, and the proposed optical encoding scheme can effectively eliminate security deficiency and significantly enhance cryptosystem security. The proposed strategy based on the rotatable phase-only mask can provide a new alternative for data/image encryption in the noninterferometric imaging.

  13. Color Image Encryption Algorithm Based on Chaos and FRFT%基于混沌和FRFT的彩色图像加密算法

    Institute of Scientific and Technical Information of China (English)

    邢丽坤; 华正春; 牛秀龄; 李昕; 武月

    2016-01-01

    In order to strengthen the confidentiality of the image, and to restore the original color image information. This paper proposes a color image based on chaos and fractional Fourier transform encryption algorithm. Specific process is:First of all, Let the image is divided into three parts,for R、G、B. And then the chaotic encryption, finally the discrete FRFT encryption. Use of MATLAB simulation show that the algorithm has good encryption and decryption,It can better hide and save the information of color image.%为了增强图像的保密性,恢复原彩色图像信息,提出了一种基于混沌和分数阶Fourier变换的彩色图像信息加密的算法。具体加密过程为:首先将原图像信号分为R、G、B三个灰色图像,其次对各个图像做混沌算法加密,最后再进行离散FRFT加密,输出最终的密文。利用MATLAB的仿真实验表明,此算法的图像加密和解密效果较好,能够较好的隐藏和保存彩色图像的信息。

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

    Science.gov (United States)

    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.

  15. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  16. Image encryption using eight dimensional chaotic cat map

    Science.gov (United States)

    Ganesan, K.; Murali, K.

    2014-06-01

    In recent years, a large number of discrete chaotic cryptographic algorithms have been proposed. However, most of them encounter some problems such as lack of robustness and security. In this paper, we introduce a new image encryption algorithm based on eight-dimensional (nonlinear) chaotic cat map. Encryption of image is different from that of texts due to some intrinsic features of image such as bulk data capacity and high redundancy, which are generally difficult to handle by traditional methods. In traditional methods the key space is small and the security is weak. The proposed algorithm tries to address these problems and also tries to enhance the encryption speed. In this paper an eight dimensional chaotic cat map is used to encrypt the intensity values of pixels using lookup table method thereby significantly increasing the speed and security of encryption. The proposed algorithm is found to be resistive against chosen/known-plaintext attacks, statistical and differential attacks.

  17. Improved Cryptanalysis of CMC Chaotic Image Encryption Scheme

    Directory of Open Access Journals (Sweden)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  19. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  20. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  1. Multiple-image encryption and multiplexing using a modified Gerchberg-Saxton algorithm and phase modulation in Fresnel-transform domain.

    Science.gov (United States)

    Hwang, Hone-Ene; Chang, Hsuan T; Lie, Wen-Nung

    2009-12-15

    What we believe to be a new technique, based on a modified Gerchberg-Saxton algorithm (MGSA) and a phase modulation scheme in the Fresnel-transform domain, is proposed to reduce cross talks existing in multiple-image encryption and multiplexing. First, each plain image is encoded and multiplexed into a phase function by using the MGSA and a different wavelength/position parameter. Then all the created phase functions are phase modulated to result in different shift amounts of the reconstruction images before being combined together into a single phase-only function. Simulation results show that the cross talks between multiplexed images have been significantly reduced, compared with prior methods [Opt. Lett.30, 1306 (2005); J. Opt. A8, 391 (2006)], thus presenting high promise in increasing the multiplexing capacity and encrypting grayscale and color images.

  2. New Image Scrambling Hiding Algorithm Based on Chaotic Proliferation Encryption%基于混沌扩散加密的图像置乱隐藏算法

    Institute of Scientific and Technical Information of China (English)

    牛永洁; 赵耀锋

    2013-01-01

    In recent years,digital image information hiding technology has been the hot research topics in digital image information hiding.Digital images as carriers of information hiding are not different from traditional encryption methods,the use of information hiding generated by images with the confusing can stand attacks from a malicious person.The combination of two-dimensional logistic encryption algorithm and digital image hiding algorithm uses a large space and image scrambling hidden characteristics.Although the expense of encryption is not efficiency,security and hidden are better,and it is more suitable for practical application,fully embodies the proliferation of encryption,enhances the ability of scrambling algorithm.The security analysis proves that the algorithm is of enough key space and good hideaway effect.%数字图像信息隐藏技术是近年信息隐藏技术中的热点研究课题,以数字图像作为载体的信息隐藏与传统加密方法不同,利用图像所具有的迷惑性产生的隐藏信息更能经受起恶意者的攻击.本文基于混沌扩散构建图像置乱隐藏算法,利用混沌加密密钥空间大和图像置乱隐藏性能好的双重特点,虽然牺牲一部分扩散加密效率,但安全性和隐藏性更好,更适合实际应用,充分体现了加密扩散性,增强了算法置乱能力.实验证明,该算法具有密钥空间大、隐藏效果好等特点.

  3. Reversible Data Hiding In Encrypted Images by Reserving Room before Encryption

    Directory of Open Access Journals (Sweden)

    Harish G, Smitha Shekar B, Prajwal R, Sunil S Shetty

    2014-07-01

    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 subject to some errors on data extraction and/or image restoration. Here, a novel method is proposed so as to reserve 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. The proposed method can achieve real reversibility, i.e., data extraction and image recovery are free of any error.

  4. Chaotic Image Encryption with Random Shuffling of Data

    Directory of Open Access Journals (Sweden)

    Murat Aydos

    2014-02-01

    Full Text Available Security of valuable multimedia contents such as images in personal photograph albums, electronic publishing, frames of multicast video conference can be achieved by image encryption. Secure transmission of these contents is required to be rapid, efficient and practical. Hence, image encryption process must be chosen not only to satisfy the security goals but also to fulfill these requirements. Due to the inadequacy and inefficiency of conventional text based information encryption methods, researchers have proposed several encryption schemes. Many of them are based on chaotic algorithms. Recently, the studies are concentrated on some weaknesses of chaotic algorithms and most of the presented solutions came up with complex structured chaotic maps. In this paper, we present a self-diagonal shuffler mechanism embedded to one dimensional chaotic encryption system to overcome its leak points while keeping simplicity and efficiency properties.

  5. Digital image encryption with chaotic map lattices

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

  8. Image Encryption Algorithm Based on Chaotic Mappings%基于混沌映射的图像加密算法

    Institute of Scientific and Technical Information of China (English)

    卢辉斌; 肖霞

    2011-01-01

    This paper designs a new kind of image encryption algorithm which uses two Logistic systems. The auxiliary key m is obtained by a certain line data of the changed image matrix. The initial values of two Logistic mappings are modified by the key in. The Logistic mappings are used to generate the encryption sequences which are used to encrypt with every pixel of the image. Theoretical analysis and simulation results show the new algorithm not only has better sensitivity and very uniform pixel-value distribution, but also is simple and easy to achieve.%提出一种基于混沌映射的图像加密算法,该算法对图像进行拉伸融合折叠变换,通过映射其矩阵的某行数据,得到修改Logistic 映射初值的关键密钥m,并由2个Logistic混沌映射相结合产生加密序列,将图像与该序列进行相应代数运算,从而获得加密图像.理论分析和实验结果表明,该算法对密钥具有较强的敏感性,且加密图的像素值分布较均匀.

  9. Self Contained Encrypted Image Folding

    CERN Document Server

    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.

  10. Chaotic trigonometric Haar wavelet with focus on image encryption

    OpenAIRE

    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...

  11. 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

    Institute of Scientific and Technical Information of China (English)

    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。

  12. Study on Digital Image Scrambling Algorithm

    OpenAIRE

    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...

  13. Research on medical image encryption in telemedicine systems.

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

  16. Image Encryption based on the RGB PIXEL Transposition and Shuffling

    Directory of Open Access Journals (Sweden)

    Quist Aphetsi Kester

    2013-06-01

    Full Text Available Privacy is one of the key issues information Security addresses. Through encryption one can prevent a third party from understanding raw data during signal transmission. The encryption methods for enhancing the security of digital contents has gained high significance in the current era of breach of security and misuse of the confidential information intercepted and misused by the unauthorized parties. This paper sets out to contribute to the general body of knowledge in the area of cryptography application and by developing a cipher algorithm for image encryption of m*n size by shuffling the RGB pixel values. The algorithm ultimately makes it possible for encryption and decryption of the images based on the RGB pixel. The algorithm was implemented using MATLAB.

  17. Color image encryption based on Coupled Nonlinear Chaotic Map

    Energy Technology Data Exchange (ETDEWEB)

    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.

  18. A fractal-based image encryption system

    KAUST Repository

    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.

  19. 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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Optical encryption for large-sized images

    Science.gov (United States)

    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.

  2. PEA: Polymorphic Encryption Algorithm based on quantum computation

    OpenAIRE

    Komninos, N.; Mantas, G.

    2011-01-01

    In this paper, a polymorphic encryption algorithm (PEA), based on basic quantum computations, is proposed for the encryption of binary bits. PEA is a symmetric key encryption algorithm that applies different combinations of quantum gates to encrypt binary bits. PEA is also polymorphic since the states of the shared secret key control the different combinations of the ciphertext. It is shown that PEA achieves perfect secrecy and is resilient to eavesdropping and Trojan horse attacks. A securit...

  3. Dual-Layer Video Encryption using RSA Algorithm

    Science.gov (United States)

    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.

  4. Hardware Realization of Chaos Based Symmetric Image Encryption

    KAUST Repository

    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.

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

    Science.gov (United States)

    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.

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

    OpenAIRE

    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...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  9. Space-based optical image encryption.

    Science.gov (United States)

    Chen, Wen; Chen, Xudong

    2010-12-20

    In this paper, we propose a new method based on a three-dimensional (3D) space-based strategy for the optical image encryption. The two-dimensional (2D) processing of a plaintext in the conventional optical encryption methods is extended to a 3D space-based processing. Each pixel of the plaintext is considered as one particle in the proposed space-based optical image encryption, and the diffraction of all particles forms an object wave in the phase-shifting digital holography. The effectiveness and advantages of the proposed method are demonstrated by numerical results. The proposed method can provide a new optical encryption strategy instead of the conventional 2D processing, and may open up a new research perspective for the optical image encryption.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

  14. Cryptanalysis of "an improvement over an image encryption method based on total shuffling"

    Science.gov (United States)

    Akhavan, A.; Samsudin, A.; Akhshani, A.

    2015-09-01

    In the past two decades, several image encryption algorithms based on chaotic systems had been proposed. Many of the proposed algorithms are meant to improve other chaos based and conventional cryptographic algorithms. Whereas, many of the proposed improvement methods suffer from serious security problems. In this paper, the security of the recently proposed improvement method for a chaos-based image encryption algorithm is analyzed. The results indicate the weakness of the analyzed algorithm against chosen plain-text.

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

    OpenAIRE

    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...

  16. Image Encryption Based On Diffusion And Multiple Chaotic Maps

    Directory of Open Access Journals (Sweden)

    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.

  17. Gray-scale and color optical encryption based on computational ghost imaging

    Science.gov (United States)

    Tanha, Mehrdad; Kheradmand, Reza; Ahmadi-Kandjani, Sohrab

    2012-09-01

    We propose two approaches for optical encryption based on computational ghost imaging. These methods have the capability of encoding ghost images reconstructed from gray-scale images and colored objects. We experimentally demonstrate our approaches under eavesdropping in two different setups, thereby proving the robustness and simplicity thereof for encryption compared with previous algorithms.

  18. Watermarking patient data in encrypted medical images

    Indian Academy of Sciences (India)

    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.

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

    Science.gov (United States)

    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.

  20. Double-image encryption based on discrete fractional random transform and chaotic maps

    Science.gov (United States)

    Li, Huijuan; Wang, Yurong

    2011-07-01

    A novel double-image encryption algorithm is proposed, based on discrete fractional random transform and chaotic maps. The random matrices used in the discrete fractional random transform are generated by using a chaotic map. One of the two original images is scrambled by using another chaotic map, and then encoded into the phase of a complex matrix with the other original image as its amplitude. Then this complex matrix is encrypted by the discrete fractional random transform. By applying the correct keys which consist of initial values, control parameters, and truncated positions of the chaotic maps, and fractional orders, the two original images can be recovered without cross-talk. Numerical simulation has been performed to test the validity and the security of the proposed encryption algorithm. Encrypting two images together by this algorithm creates only one encrypted image, whereas other single-image encryption methods create two encrypted images. Furthermore, this algorithm requires neither the use of phase keys nor the use of matrix keys. In this sense, this algorithm can raise the efficiency when encrypting, storing or transmitting.

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

    Science.gov (United States)

    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.

  2. Optical color-image encryption and synthesis using coherent diffractive imaging in the Fresnel domain.

    Science.gov (United States)

    Chen, Wen; Chen, Xudong; Sheppard, Colin J R

    2012-02-13

    We propose a new method using coherent diffractive imaging for optical color-image encryption and synthesis in the Fresnel domain. An optical multiple-random-phase-mask encryption system is applied, and a strategy based on lateral translations of a phase-only mask is employed during image encryption. For the decryption, an iterative phase retrieval algorithm is applied to extract high-quality decrypted color images from diffraction intensity maps (i.e., ciphertexts). In addition, optical color-image synthesis is also investigated based on coherent diffractive imaging. Numerical results are presented to demonstrate feasibility and effectiveness of the proposed method. Compared with conventional interference methods, coherent diffractive imaging approach may open up a new research perspective or can provide an effective alternative for optical color-image encryption and synthesis.

  3. Study on Digital Image Scrambling Algorithm

    Directory of Open Access Journals (Sweden)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    OpenAIRE

    Yu, Hua; Wu, Zhen-hua

    2012-01-01

    To establish a sound traceability system of agricultural products, 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 conv...

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

    Directory of Open Access Journals (Sweden)

    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.

  7. Optical encryption with selective computational ghost imaging

    Science.gov (United States)

    Zafari, Mohammad; kheradmand, Reza; Ahmadi-Kandjani, Sohrab

    2014-10-01

    Selective computational ghost imaging (SCGI) is a technique which enables the reconstruction of an N-pixel image from N measurements or less. In this paper we propose an optical encryption method based on SCGI and experimentally demonstrate that this method has much higher security under eavesdropping and unauthorized accesses compared with previous reported methods.

  8. Interference-based multiple-image encryption with silhouette removal by position multiplexing.

    Science.gov (United States)

    Qin, Yi; Gong, Qiong

    2013-06-10

    An approach for multiple-image encryption based on interference and position multiplexing is proposed. In the encryption process, multiple images are analytically hidden into three phase-only masks (POMs). The encryption algorithm for this method is quite simple and does not need iterative encoding. For decryption, both the digital method and optical method could be employed. Also, we analyze the multiplexing capacity through the correlation coefficient. In addition, the silhouette problem that exists in previous interference-based encryption methods with two POMs can be eliminated during the generation procedure of POMs based on the interference principle. Simulation results are presented to verify the validity of the proposed approach.

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

    Science.gov (United States)

    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.

  10. Selective image encryption for Medical and Satellite Images

    OpenAIRE

    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...

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

    Institute of Scientific and Technical Information of China (English)

    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.

  12. Selective image encryption for Medical and Satellite Images

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Encryption of Messages and Images Using Compressed Sensing

    OpenAIRE

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. Multiple-image encryption based on computational ghost imaging

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Image Encryption Using Fibonacci-Lucas Transformation

    OpenAIRE

    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...

  2. Image encryption combining multiple generating sequences controlled fractional DCT with dependent scrambling and diffusion

    Science.gov (United States)

    Liang, Yaru; Liu, Guoping; Zhou, Nanrun; Wu, Jianhua

    2015-02-01

    Based on the fractional discrete cosine transform with multiple generating sequences (MGSFrDCT) and the dependent scrambling and diffusion (DSD), an image encryption algorithm is proposed, in which the multiple-generating sequences greatly enlarge the key space of the encryption system. The real-valued output of MGSFrDCT is beneficial to storage, display and transmission of the cipher-text. During the stage of confusion and diffusion, the locations and values of all MGSFrDCT transformed coefficients change due to DSD, and the initial values and fractional orders of encryption system depend not only on the cipher keys but also on the plain-image due to introduction of a disturbance factor, which allows the encryption system to resist the known-plaintext and chosen-plaintext attacks. Experimental results demonstrate that the proposed encryption algorithm is feasible, effective and secure and able to resist common classical attacks.

  3. Encryption-Decryption RGB Color Image Using Matrix Multiplication

    OpenAIRE

    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...

  4. 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

    Institute of Scientific and Technical Information of China (English)

    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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  8. Steganographic optical image encryption system based on reversible data hiding and double random phase encoding

    Science.gov (United States)

    Chuang, Cheng-Hung; Chen, Yen-Lin

    2013-02-01

    This study presents a steganographic optical image encryption system based on reversible data hiding and double random phase encoding (DRPE) techniques. Conventional optical image encryption systems can securely transmit valuable images using an encryption method for possible application in optical transmission systems. The steganographic optical image encryption system based on the DRPE technique has been investigated to hide secret data in encrypted images. However, the DRPE techniques vulnerable to attacks and many of the data hiding methods in the DRPE system can distort the decrypted images. The proposed system, based on reversible data hiding, uses a JBIG2 compression scheme to achieve lossless decrypted image quality and perform a prior encryption process. Thus, the DRPE technique enables a more secured optical encryption process. The proposed method extracts and compresses the bit planes of the original image using the lossless JBIG2 technique. The secret data are embedded in the remaining storage space. The RSA algorithm can cipher the compressed binary bits and secret data for advanced security. Experimental results show that the proposed system achieves a high data embedding capacity and lossless reconstruction of the original images.

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

    Directory of Open Access Journals (Sweden)

    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.

  10. 基于骑士巡游的灰度图像加密压缩算法%Algorithm of Gray Image Encryption and Compression Based on Knight's Tour

    Institute of Scientific and Technical Information of China (English)

    刘博文; 柏森; 刘程浩; 杜鹤峣

    2012-01-01

    In order to improve the storage and transmission efficiency of confidential images, an algorithm of gray image encryption and compression based on knight's tour is proposed. In this algorithm original image is divided into blocks of 8 ×8, then every block is transformed by DCT to build coefficient blocking matrix. The coefficient blocking matrix is scrambled by the knight's tour to get encrypted image, then the encrypted compressed image could be gained after JPEG compression. The experimental results and analysis show that the algorithm has good effects such as the huge key space and the strong sensitivity. It gets higher compression efficiency on premise of some degree of scrambling.%为了进一步提高涉密图像的存储和传输效率,提出了基于骑士巡游的灰度图像加密压缩算法.该算法将原始图像进行8×8分块,对每个块进行DCT变换,构建以块为单位的系数块化矩阵,然后采用骑士巡游置乱对该系数块化矩阵加密,对置乱加密后图像进行JPEG压缩得到加密压缩图像.实验仿真和分析表明,该算法密钥空间大、密钥敏感性高,在保证一定置乱度的前提下,获得了更高的压缩效率.

  11. IMAGE ENCRYPTION ALGORITHM BASED ON HNON MAPPING AND MAGIC CUBE TRANSFORMATION%基于Hénon映射与魔方变换的图像加密算法

    Institute of Scientific and Technical Information of China (English)

    董虎胜; 陆萍; 钟宝江

    2014-01-01

    We propose an image encryption algorithm,it is based on improved Hénon mapping and magic cube transformation,makes use of improved Hénon mapping sequence to have more ideal statistical and distribution properties,and is more suitable for image encryption.The algorithm first changes the pixels value of image by carrying out XOR operation on them using obtained integer sequence,and then decompose the image into a 3-dimensional matrix,finally,makes the cyclic shift operation on data of each plane by rings along with every axis in 3-dimensional space,that is,uses magic cube rotation transformation to complete image data scrambling.The encryption algorithm has the advantages of low computational cost,large key space,and applicable to all kinds of images.Simulation experimental results show that the algorithm has good image encryption effect,and has quite strong anti-interference capability against common attacks.%提出一种基于改进的Hénon映射与魔方变换的图像加密算法。该加密算法采用改进的Hénon映射序列,使其具有更为理想的统计与分布特性,更适用于图像加密。算法首先利用获得的整数序列与图像的像素值运算而使其改变,再将图像分解为三维数据矩阵,在三维空间沿每一轴向对各平面中的数据按环作循环移位操作,即采用魔方旋转变换完成对图像数据的置乱。该加密算法具有运算量低、密钥空间大与图像普适性等优点。仿真实验结果表明该算法具有良好的图像加密效果,对于常见的攻击具有较强的抗干扰能力。

  12. Image Encryption Using Differential Evolution Approach in Frequency Domain

    CERN Document Server

    Hassan, Maaly Awad S; 10.5121/sipij.2011.2105

    2011-01-01

    This paper presents a new effective method for image encryption which employs magnitude and phase manipulation using Differential Evolution (DE) approach. The novelty of this work lies in deploying the concept of keyed discrete Fourier transform (DFT) followed by DE operations for encryption purpose. To this end, a secret key is shared between both encryption and decryption sides. Firstly two dimensional (2-D) keyed discrete Fourier transform is carried out on the original image to be encrypted. Secondly crossover is performed between two components of the encrypted image, which are selected based on Linear Feedback Shift Register (LFSR) index generator. Similarly, keyed mutation is performed on the real parts of a certain components selected based on LFSR index generator. The LFSR index generator initializes it seed with the shared secret key to ensure the security of the resulting indices. The process shuffles the positions of image pixels. A new image encryption scheme based on the DE approach is developed...

  13. Optical encryption in spatially-incoherent light using two LC SLMs for both information input and encryption element imaging

    Science.gov (United States)

    Bondareva, Alyona P.; Cheremkhin, Pavel A.; Evtikhiev, Nikolay N.; Krasnov, Vitaly V.; Rodin, Vladislav G.; Starikov, Sergey N.

    2014-10-01

    At present time methods of optical encryption are actively developed. The majority of existing methods of optical encryption use not only light intensity distribution, easily registered with photosensors, but also its phase distribution which require application of complex holographic schemes in conjunction with spatially coherent monochromatic illumination. This leads to complex optical schemes and low decryption quality. To eliminate these disadvantages it is possible to implement optical encryption using spatially incoherent monochromatic illumination which requires registration of light intensity distribution only. Encryption is accomplished by means of optical convolution of image of scene to be encrypted and encryption diffractive optical element (DOE) point spread function (PSF) which serves as encryption key. Encryption process is described as follows. Scene is illuminated with spatially-incoherent monochromatic light. In the absence of encryption DOE lens forms image of scene in photosensor plane. DOE serves as encryption element, its PSF - encryption key. Light passing through DOE forms convolution of object image and DOE PSF. Registered by photosensor convolution is encrypted image. Decryption was conducted numerically on computer by means of inverse filtration with regularization. Kinoforms were used as encryption DOE because they have single diffraction order. Two liquid crystal (LC) spatial light modulators (SLM) were used to implement dynamic digital information input and dynamic encryption key change. As input scene amplitude LC SLM HoloEye LC2002 with 800×600 pixels 32×32 μm2 and 256 gray levels was used. To image synthesized encryption kinoforms phase LC SLM HoloEye PLUTO VIS with 1920×1080 pixels 8×8 μm2 and 256 phase levels was used. Set of test images was successfully optically encrypted and then numerically decrypted. Encrypted images contents are hidden. Decrypted images despite quite high noise levels are positively recognizable

  14. Selective Encryption of Human Skin in JPEG Images

    OpenAIRE

    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 ...

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

    OpenAIRE

    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...

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

    OpenAIRE

    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...

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

    Science.gov (United States)

    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.

  18. Application of Cosine Zone Plates to Image Encryption

    Institute of Scientific and Technical Information of China (English)

    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.

  19. A fast chaotic block cipher for image encryption

    Science.gov (United States)

    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.

  20. Reducing Computational Time of Basic Encryption and Authentication Algorithms

    Directory of Open Access Journals (Sweden)

    Sandeep Kumar,

    2011-04-01

    Full Text Available Today most of data are sending via the internet for sharing, so the trust of data files is decreased. For the trust more security and authentication is needed, less security increase the liability ofattacks on data. Digital signature of the data is a solution to this security problem which provides the reliability, authenticity and accuracy. Most basic algorithm for security and authentication is RSA, DSA, algorithms which uses the different key of different sizes. This work presents ECDSA algorithm to encrypt the data, use parameterized hash algorithm to authenticate the data and also compare both RSA and ECDSA methods in respect of time parameters.

  1. Shannon Entropy based Randomness Measurement and Test for Image Encryption

    CERN Document Server

    Wu, Yue; Agaian, Sos

    2011-01-01

    The quality of image encryption is commonly measured by the Shannon entropy over the ciphertext image. However, this measurement does not consider to the randomness of local image blocks and is inappropriate for scrambling based image encryption methods. In this paper, a new information entropy-based randomness measurement for image encryption is introduced which, for the first time, answers the question of whether a given ciphertext image is sufficiently random-like. It measures the randomness over the ciphertext in a fairer way by calculating the averaged entropy of a series of small image blocks within the entire test image. In order to fulfill both quantitative and qualitative measurement, the expectation and the variance of this averaged block entropy for a true-random image are strictly derived and corresponding numerical reference tables are also provided. Moreover, a hypothesis test at significance?-level is given to help accept or reject the hypothesis that the test image is ideally encrypted/random-...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  8. Bi-serial DNA Encryption Algorithm(BDEA)

    CERN Document Server

    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

  9. Adaptive Image Encryption Algorithm Based on Chaos Theory and Hash Function%基于混沌理论和Hash函数的自适应图像加密算法

    Institute of Scientific and Technical Information of China (English)

    赵希奇; 柏逢明; 吕贵花

    2014-01-01

    In this paper, a image encryption algorithm based on chaos theory and Hash functions are proposed for achive the digital image encryption. The scrambling transformation pixel matrix of image is got from extraction chaotic signal and Hash function by using the algorithm,then the adaptive diffusion for image gray scale is carried out by using piecewise Logistic mapping. This algorithm has large key space;the statistical attack capability is strong and effective against entropy attack;secret key sensitivity is strong,good performance;the corresponding security level can be met.%为了实现对数字图像的加密,提出了一种基于混沌理论和Hash函数的自适应图像加密算法。该算法用抽取的Lorenz混沌信号及Hash函数得到像素置乱矩阵,并对图像的像素进行置乱,利用分段Logistic映射对图像灰度进行自适应扩散。理论分析和仿真实验结果表明,该算法具有密钥空间大、抗统计攻击能力强、有效抵抗熵攻击、秘钥敏感性强等良好的性能,能够达到相应的安全水平。

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

    OpenAIRE

    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...

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

    Science.gov (United States)

    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.

  12. 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

    Institute of Scientific and Technical Information of China (English)

    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。

  13. Plaintext Related Image Encryption Scheme Using Chaotic Map

    Directory of Open Access Journals (Sweden)

    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.

  14. Encryption-Decryption RGB Color Image Using Matrix Multiplication

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Security analysis of image encryption algorithm for a class of fractional Fourier transform%一类分数傅里叶变换图像加密算法的安全分析

    Institute of Scientific and Technical Information of China (English)

    周业勤; 龙敏

    2015-01-01

    According to the properties of fractional Fourier transform, a kind of fractional Fourier transform image encryp-tion algorithm is analyzed. The key is not sensitive and the deciphering diagram is of great distortion, when with the naked eye on results chart to judge and extract the image data for comparison. Theoretical analysis and experimental results show that the algorithm is not sensitive to the key when the fractional Fourier transform is directly applied to image encryption. The introduction of RGB mapping to realize the cipher image display and transmission, result a great distortion in pixels.%从分数阶傅里叶变换的性质出发,对一类分数阶傅里叶变换图像加密算法进行分析。对原有算法结果图进行肉眼判断,提取图像中间结果数据进行对比分析,可知算法的密钥具有不敏感性,并且解密图具有很大失真。对分数傅里叶变换进行理论上的分析和讨论。分析及实验结果表明,直接使用分数阶傅里叶变换进行加密的算法对密钥并不敏感,存在安全隐患。为实现密文图像的显示和传输而引入的RGB映射将导致解密图像像素值失真。

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

    Science.gov (United States)

    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

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

    OpenAIRE

    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...

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

    OpenAIRE

    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....

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

    OpenAIRE

    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 ...

  2. NEW SYMMETRIC ENCRYPTION SYSTEM BASED ON EVOLUTIONARY ALGORITHM

    Directory of Open Access Journals (Sweden)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  4. Chaotic image encryption based on running-key related to plaintext.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Fractional Hartley transform applied to optical image encryption

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Cryptanalysis of a novel image encryption scheme based on improved hyperchaotic sequences

    Science.gov (United States)

    Özkaynak, Fatih; Özer, Ahmet Bedri; Yavuz, Sırma

    2012-11-01

    Chaotic cryptography is a new field that has seen a significant amount of research activity during the last 20 years. Despite the many proposals that use various methods in the design of encryption algorithms, there is a definite need for a mathematically rigorous cryptanalysis of these designs. In this study, we analyze the security weaknesses of the "C. Zhu, A novel image encryption scheme based on improved hyperchaotic sequences, Optics Communications 285 (2012) 29-37". By applying chosen plaintext attacks, we show that all the secret parameters can be revealed.

  10. 基于改进AES加密算法的DICOM医学图像安全性研究%Research on the Security of DICOM Medical Images Based on Improved AES Encryption Algorithm

    Institute of Scientific and Technical Information of China (English)

    向涛; 余晨韵; 屈晋宇; 罗小松

    2012-01-01

    In this paper,a medical image encryption algorithm is proposed. The algorithm is based on the design principle of AES, and combined with Skew tent map. The standard procedure of AES is modified so that it can be suitable for the DICOM medical digital images. At first, the block size 4 * 4 in AddRoundKey is replaced by the size of an image.Then the basic information of patient is protected by our proposed algorithm. In addition,the AES's MixColumns and key schedule are improved.The theoretical analysis and numerical simulations show that the improved algorithm not only has better confusion diffusion effects with less computational overhead,but also can maintain the compatibility of DICOM file format.%本文基于AES算法的设计原理提出了一种改进的医学图像加密算法.针对AES算法结合斜帐篷映射对其进行改进,使其适合DICOM医学图像的数据特点.首先将AES中4*4的分块操作方式变成M*N的全图操作,其次增加了对病人基本信息的保护,最后改进了AES中列混合操作与密钥编排方式.通过理论分析与仿真实验证明改进算法具有较好的置乱效果、扩散性强,并且能够很好地保持DICOM文件格式的兼容性.

  11. UNIVERSAL DIGITAL IMAGE ENCRYPTION AND RECOVERY ALGORITHM BASED ON 3 D CHAOTIC SYSTEM%基于三维混沌系统的通用数字图像加密与恢复算法

    Institute of Scientific and Technical Information of China (English)

    卢守东; 肖芳雄

    2013-01-01

    In order to protect digital image information effectively , a new universal encryption algorithm based on 3D chaotic system and its improved sequences is proposed .Firstly, according to the key and the digital image size m ×n , a 3D chaotic sequence with length of m ×n is generated .Then, the chaotic sequence is improved to possess the ideal pseudo-randomness property according to the sub-key and the type of image.Also according to the sub-key and the type of image , at the same time the chaotic sequence is converted to unsigned integer se-quence.Finally, the improved sequence is sorted for generating the corresponding subscript sequence , and pixel coordinates of the image will be scrambled based on it .Meanwhile , the pixel value permutation is realised by using the XOR operation between the unsigned integer se -quence and the corresponding pixel value in turn .In allusion to the malicious shearing or painting attacks ,a recovery algorithm based on neigh-bouring pixels characteristic is presented simultaneously .The effect of the encryption and security is also analysed by using the evaluation in-dex.Experimental results and theoretical analysis show that the algorithm has high running efficiency , large space of keys , good encryption effect, statistical characteristics and security , it also has strong ability in resisting the shearing or painting attacks and anti-noise as well.%为有效保护数字图像的信息,提出一种新的基于三维混沌系统及其改进序列的通用加密算法。首先,根据密钥及数字图像的大小m ×n,产生一个长度为m ×n的三维混沌序列。然后,根据子密钥及图像类型对混沌序列进行改进,使其具有理想的伪随机特性。同时,根据子密钥及图像类型将混沌序列转换为无符号整数序列。最后,对改进后的序列进行排序以生成相应的下标序列,并据此对图像进行像素坐标置乱,同时将无符号整数序列依次与对应的

  12. DATA HIDING IN ENCRYPTED IMAGES USING ARNOLD TRANSFORM

    Directory of Open Access Journals (Sweden)

    S. Siva Shankar

    2016-08-01

    Full Text Available Digital image steganography has several applications in information security and communication. Data hiding in encrypted images ensure that both the cover image and the secret message can be recovered at the receiver end. This work presents a novel data hiding and image encryption scheme using random diffusion and Two dimensional Arnold cat mapping transform. The secret message bits are placed in the least significant bit positions of the cover image. Then a shared key is used to generate random 8 bit random integer stream and is added to the stego image in the random diffusion step. Arnold cat mapping transformation is done to scramble the pixels. The two steps of random diffusion and Arnold transform mapping are done alternatively several times to completely encrypt the image contents. The process is reversed at the receiver end to get both the secret message and the cover image with little loss. The random diffusion step overcomes the limited period of the Arnold transform. The embedding capacity of one bit per pixel is achieved. Security analysis is carried out which shows that the encryption is highly secure. The number of collisions is low thus preventing brute force attacks. The original cover image is recoverable with minimal losses.

  13. 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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  15. Chaotic Image Scrambling Algorithm Based on S-DES

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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.

  17. Optical Image Encryption with Simplified Fractional Hartley Transform

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    OpenAIRE

    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...

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

    Science.gov (United States)

    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.

  1. Color image encryption based on gyrator transform and Arnold transform

    Science.gov (United States)

    Sui, Liansheng; Gao, Bo

    2013-06-01

    A color image encryption scheme using gyrator transform and Arnold transform is proposed, which has two security levels. In the first level, the color image is separated into three components: red, green and blue, which are normalized and scrambled using the Arnold transform. The green component is combined with the first random phase mask and transformed to an interim using the gyrator transform. The first random phase mask is generated with the sum of the blue component and a logistic map. Similarly, the red component is combined with the second random phase mask and transformed to three-channel-related data. The second random phase mask is generated with the sum of the phase of the interim and an asymmetrical tent map. In the second level, the three-channel-related data are scrambled again and combined with the third random phase mask generated with the sum of the previous chaotic maps, and then encrypted into a gray scale ciphertext. The encryption result has stationary white noise distribution and camouflage property to some extent. In the process of encryption and decryption, the rotation angle of gyrator transform, the iterative numbers of Arnold transform, the parameters of the chaotic map and generated accompanied phase function serve as encryption keys, and hence enhance the security of the system. Simulation results and security analysis are presented to confirm the security, validity and feasibility of the proposed scheme.

  2. Optical asymmetric image encryption using gyrator wavelet transform

    Science.gov (United States)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    CERN Document Server

    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...

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Image encryption using the two-dimensional logistic chaotic map

    Science.gov (United States)

    Wu, Yue; Yang, Gelan; Jin, Huixia; Noonan, Joseph P.

    2012-01-01

    Chaos maps and chaotic systems have been proved to be useful and effective for cryptography. In our study, the two-dimensional logistic map with complicated basin structures and attractors are first used for image encryption. The proposed method adopts the classic framework of the permutation-substitution network in cryptography and thus ensures both confusion and diffusion properties for a secure cipher. The proposed method is able to encrypt an intelligible image into a random-like one from the statistical point of view and the human visual system point of view. Extensive simulation results using test images from the USC-SIPI image database demonstrate the effectiveness and robustness of the proposed method. Security analysis results of using both the conventional and the most recent tests show that the encryption quality of the proposed method reaches or excels the current state-of-the-art methods. Similar encryption ideas can be applied to digital data in other formats (e.g., digital audio and video). We also publish the cipher MATLAB open-source-code under the web page https://sites.google.com/site/tuftsyuewu/source-code.

  10. IMAGE ENCRYPTION TECHNIQUES USING CHAOTIC SCHEMES: A REVIEW

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    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...

  12. Design of an image encryption scheme based on a multiple chaotic map

    Science.gov (United States)

    Tong, Xiao-Jun

    2013-07-01

    In order to solve the problem that chaos is degenerated in limited computer precision and Cat map is the small key space, this paper presents a chaotic map based on topological conjugacy and the chaotic characteristics are proved by Devaney definition. In order to produce a large key space, a Cat map named block Cat map is also designed for permutation process based on multiple-dimensional chaotic maps. The image encryption algorithm is based on permutation-substitution, and each key is controlled by different chaotic maps. The entropy analysis, differential analysis, weak-keys analysis, statistical analysis, cipher random analysis, and cipher sensibility analysis depending on key and plaintext are introduced to test the security of the new image encryption scheme. Through the comparison to the proposed scheme with AES, DES and Logistic encryption methods, we come to the conclusion that the image encryption method solves the problem of low precision of one dimensional chaotic function and has higher speed and higher security.

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

    OpenAIRE

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Quasi-Linear Time Fully Homomorphic Public Key Encryption Algorithm (ZK111

    Directory of Open Access Journals (Sweden)

    Zaryab Khan

    2012-11-01

    Full Text Available ZK111 is a quasi-linear O(n · log n fully Homomorphic encryption (FHE algorithm. It works on a novel idea of “perfectly colorblind function” which is nothing but a very unique way of creating p-adic ring homomorphism from p-adic ring X to p-adic ring Y. Unlike its other FHE counterparts, there is NO “noise” in the cipher text. ZK111 preserves full algebraic homomorphism without compromising its quasi-linear efficiency. It is not only FHE, but also the fastest public-key encryption (PKE algorithm known as of today.. Both encryption and decryption are O(n · log n and algorithm still retains it FHE property. Hence it solves the most intriguing and outstanding problem of cryptography. ZK111 is a probabilistic encryption algorithm by nature, and despite being FHE; it is absolutely immune to chosen and adoptive plaintext attack by design.

  16. Gauss-Markov encryption matrix construct and image encryption application%Gauss-Markov加密矩阵构造及图像加密应用

    Institute of Scientific and Technical Information of China (English)

    邹阿金; 刘勇华; 罗移祥

    2012-01-01

    To solve the problem of encryption matrix is difficult to construct, a novel algorithm is proposed to get the encryption matrix. First, a stochastic sequence is generated by Gauss-Markov process. Then, it is converted into a series of low-order integer matrixes and multiple the selected matrices with determinant equal to 1 each other by using tensor production method. Thus, we can construct some high order encryption matrices and use it in digital image encryption. The encryption instance and theoretical analysis show that the proposed algorithm can produce encryption matrices with high security, and have good random characteristics and autocorrelation to meet the requirement of cryptography.%为了解决加密矩阵难以构造的问题,提出一种获得整数矩阵的新算法,利用Gauss-Markov过程生成一个随机序列,将该序列转换为一系列的低阶整数矩阵,从中寻找行列式等于l的整数矩阵,并对这些矩阵进行张量积运算得到高阶加密矩阵,应用于数字图像加密.加密实例和理论分析及对比表明,该算法可自动生成安全性很高的加密矩阵,且加密结果具有良好的随机特性和自相关性,能满足密码学的要求.

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

    OpenAIRE

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    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 ...

  20. 二阶可逆耦合触发细胞自动机的加密技术研究%Two-order Reversible Couple Toggle Cellular Automata Based Image Encryption Algorithm

    Institute of Scientific and Technical Information of China (English)

    彭川

    2012-01-01

    为了有效改进细胞自动机加密系统的实现复杂度和加解密效率,提出了一种二阶可逆耦合触发细胞自动机的图像加密方法.通过对简单的可逆细胞自动机进行扩展,构造二阶可逆细胞自动机,并以耦合触发规则对明文图像实行分块加密.二阶可逆细胞自动机的转移状态由其当前状态以及前一状态决定,有效增大了邻域范围,并且因为采用耦合触发规则,因此能明显增大加密系统的密钥空间,保证了系统的计算安全性.与一般触发自动机反向迭代的串行加密方式相比,该方法对于每个细胞的加密具有本质并行性,因此具有极高的加解密效率.通过实验验证其性能,结果表明与其它算法相比,该算法具有较大的密钥空间,能够有效抵抗蛮力攻击和差分分析攻击,且较小的邻域半径即可得到良好的加密效果,因此非常便于硬件实现.%To effectively improve the implement complexity and execution efficiency, an algorithm for image encryption is proposed which is based on two-order reversible couple toggle cellular automata (CA). By ways that extending the structure of simple reversible CA (RCA) and adopting couple toggle rules, the algorithm ciphers image which is divided into blocks previously. The CA's state is determined by previous state and next state, so it has larger key space and this can make system safe enough. Compared with general toggle CA (TCA) methods, the algorithm has much better efficiency because each cell is updated parallel Experiments and analysis indicate that this method has an enough large key space, high cipher and decipher speed and good scrambling effect. And the cryptosystem can resist brute attack and differential attack effectively.

  1. An image encryption scheme based on quantum logistic map

    Science.gov (United States)

    Akhshani, A.; Akhavan, A.; Lim, S.-C.; Hassan, Z.

    2012-12-01

    The topic of quantum chaos has begun to draw increasing attention in recent years. While a satisfactory definition for it is not settled yet in order to differentiate between its classical counterparts. Dissipative quantum maps can be characterized by sensitive dependence on initial conditions, like classical maps. Considering this property, an implementation of image encryption scheme based on the quantum logistic map is proposed. The security and performance analysis of the proposed image encryption is performed using well-known methods. The results of the reliability analysis are encouraging and it can be concluded that, the proposed scheme is efficient and secure. The results of this study also suggest application of other quantum maps such as quantum standard map and quantum baker map in cryptography and other aspects of security and privacy.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    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...

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

    KAUST Repository

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  8. Optical image encryption and hiding based on a modified Mach-Zehnder interferometer.

    Science.gov (United States)

    Li, Jun; Li, Jiaosheng; Shen, Lina; Pan, Yangyang; Li, Rong

    2014-02-24

    A method for optical image hiding and for optical image encryption and hiding in the Fresnel domain via completely optical means is proposed, which encodes original object image into the encrypted image and then embeds it into host image in our modified Mach-Zehnder interferometer architecture. The modified Mach-Zehnder interferometer not only provides phase shifts to record complex amplitude of final encrypted object image on CCD plane but also introduces host image into reference path of the interferometer to hide it. The final encrypted object image is registered as interference patterns, which resemble a Fresnel diffraction pattern of the host image, and thus the secure information is imperceptible to unauthorized receivers. The method can simultaneously realize image encryption and image hiding at a high speed in pure optical system. The validity of the method and its robustness against some common attacks are investigated by numerical simulations and experiments.

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

    OpenAIRE

    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...

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

    Institute of Scientific and Technical Information of China (English)

    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.

  11. Full Restoration of Visual Encrypted Color Images

    CERN Document Server

    Persson, Simeon

    2011-01-01

    While strictly black and white images have been the basis for visual cryptography, there has been a lack of an easily implemented format for colour images. This paper establishes a simple, yet secure way of implementing visual cryptography with colour, assuming a binary data representation.

  12. Chaos-based encryption for fractal image coding

    Institute of Scientific and Technical Information of China (English)

    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.

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

    CERN Document Server

    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...

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

    OpenAIRE

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    CERN Document Server

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  1. Dynamic encryption method

    DEFF Research Database (Denmark)

    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...

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    CERN Document Server

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  5. Sparse-based multispectral image encryption via ptychography

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  10. Image File Security using Base-64 Algorithm

    Directory of Open Access Journals (Sweden)

    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.

  11. Stego Optical Encryption Based on Chaotic Baker's Map Transformation

    Science.gov (United States)

    Hussain, Iqtadar; Gondal, Muhammad Asif

    2014-06-01

    In this article, an optical image encryption algorithm based on chaotic baker's map is presented. The stego-image is encrypted with the help of double random phase encoding algorithm and then produced disorder with the help of chaotic transformation. Security test shows that the reading of proposed algorithm is very close to the optimal values.

  12. Color image encryption based on color blend and chaos permutation in the reality-preserving multiple-parameter fractional Fourier transform domain

    Science.gov (United States)

    Lang, Jun

    2015-03-01

    In this paper, we propose a novel color image encryption method by using Color Blend (CB) and Chaos Permutation (CP) operations in the reality-preserving multiple-parameter fractional Fourier transform (RPMPFRFT) domain. The original color image is first exchanged and mixed randomly from the standard red-green-blue (RGB) color space to R‧G‧B‧ color space by rotating the color cube with a random angle matrix. Then RPMPFRFT is employed for changing the pixel values of color image, three components of the scrambled RGB color space are converted by RPMPFRFT with three different transform pairs, respectively. Comparing to the complex output transform, the RPMPFRFT transform ensures that the output is real which can save storage space of image and convenient for transmission in practical applications. To further enhance the security of the encryption system, the output of the former steps is scrambled by juxtaposition of sections of the image in the reality-preserving multiple-parameter fractional Fourier domains and the alignment of sections is determined by two coupled chaotic logistic maps. The parameters in the Color Blend, Chaos Permutation and the RPMPFRFT transform are regarded as the key in the encryption algorithm. The proposed color image encryption can also be applied to encrypt three gray images by transforming the gray images into three RGB color components of a specially constructed color image. Numerical simulations are performed to demonstrate that the proposed algorithm is feasible, secure, sensitive to keys and robust to noise attack and data loss.

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

    Science.gov (United States)

    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

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

    International Nuclear Information System (INIS)

    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

  15. Opto-digital image encryption by using Baker mapping and 1-D fractional Fourier transform

    Science.gov (United States)

    Liu, Zhengjun; Li, She; Liu, Wei; Liu, Shutian

    2013-03-01

    We present an optical encryption method based on the Baker mapping in one-dimensional fractional Fourier transform (1D FrFT) domains. A thin cylinder lens is controlled by computer for implementing 1D FrFT at horizontal direction or vertical direction. The Baker mapping is introduced to scramble the amplitude distribution of complex function. The amplitude and phase of the output of encryption system are regarded as encrypted image and key. Numerical simulation has been performed for testing the validity of this encryption scheme.

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Composite Chaotic Pseudo-Random Sequence Encryption Algorithm for Compressed Video

    Institute of Scientific and Technical Information of China (English)

    袁春; 钟玉琢; 杨士强

    2004-01-01

    Stream cryptosystems, which implement encryption by selecting parts of the block data and header information of the compressed video stream, achieve good real-time encryption with high flexibility. Chaotic random number generator-based approaches, for example, logistics maps, are comparatively promising approachs, but are vulnerable to attacks by nonlinear dynamic forecasting. A composite chaotic cryptography scheme was developed to encrypt the compressed video with the logistics map with a Z(231?1) field linear congruential algorithm to strengthen the security of the mono-chaotic cryptography. The scheme maintained real-time performance and flexibility of the chaotic sequence cryptography. The scheme also integrated asymmetrical public-key cryptography and encryption and identity authentification of control parameters at the initialization phase. Encryption is performed in a layered scheme based on the importance of the data in a compressed video stream. The composite chaotic cryptography scheme has the advantage that the value and updating frequency of the control parameters can be changed online to satisfy the network requirements and the processor capability, as well as the security requirements. Cryptanalysis shows that the scheme guarantees robust security,provides good real-time performance,and has flexible implementation. Statistical evaluations and tests verify that the scheme is effective.

  18. Image encryption based on the reality-preserving multiple-parameter fractional Fourier transform

    Science.gov (United States)

    Lang, Jun

    2012-05-01

    In recent years, a number of methods have been proposed in the literature for the encryption of two-dimensional information by using the fractional Fourier transform, but most of their encryptions are complex values and need digital hologram technique to record information, which is inconvenient for digital transmission. In this paper, we propose a new approach for image encryption based on the real-valuedness and decorrelation property of the reality-preserving multiple-parameter fractional Fourier transform in order to meet the requirements of the secure image transmission. In the proposed scheme, the original and encrypted images are respectively in the spatial domain and the reality-preserving multiple-parameter fractional Fourier transformed domain determined by the encryption keys. Numerical simulations are performed to demonstrate that the proposed method is reliable and more robust to blind decryption than several existing methods.

  19. Generation of keys for image optical encryption in spatially incoherent light aimed at reduction of image decryption error

    Science.gov (United States)

    Cheremkhin, Pavel A.; Evtikhiev, Nikolay N.; Krasnov, Vitaly V.; Rodin, Vladislav G.; Starikov, Sergey N.

    2014-05-01

    At present time methods of optical encryption are actively developed. The majority of existing methods of optical encryption use not only light intensity distribution, easily registered with photosensors, but also its phase distribution which require application of complex holographic schemes in conjunction with spatially coherent light. This leads to complex optical schemes and low decryption quality. To eliminate these disadvantages it is possible to implement optical encryption using spatially incoherent illumination which requires registration of light intensity distribution only. However this applies new restrictions on encryption keys: Fourier spectrum amplitude distribution of encryption key should overlap Fourier spectrum amplitude distribution of image to be encrypted otherwise loss of information is unavoidable. Therefore it seems that best key should have white spectrum. On the other hand due to fact that only light intensity distribution is registered, spectra of image to be encrypted and encryption key always have peaks at zero frequency and their heights depend on corresponding total energy. Since encrypted image contains noise, ratio of its average spectrum energy to noise average energy determines signal to noise ratio of decrypted image. Therefore ratio of amplitude at zero frequency to average spectrum amplitude (RZA) of encryption key defines decrypted images quality. For generation of encryption keys with low RZA method of direct search with random trajectory (DSRT) was used. To estimate impact of key RZA on decrypted images error numerical experiments were conducted. For experiments keys with different RZA values but with same energy value were generated and used. Numerically simulated optical encryption and decryption of set of test images was conducted. Results of experiment demonstrate that application of keys with low RZA generated by DSRT method leads to up to 20% lower error in comparison to keys generated by means of uniform random

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

    Science.gov (United States)

    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.

  1. DIGITAL COLOR IMAGE ENCRYPTION BASED ON INVERTIBLE MATRIX WITH SECRET SHARING

    Directory of Open Access Journals (Sweden)

    W.R. Sam Emmanuel

    2013-02-01

    Full Text Available This paper explores the new approach to implement image encryption in digital color images. The self invertible matrix created from the original image is used as keys for the RGB to YCbCr transform and the secret sharing operations. The encryption process carried out by the four steps: pixel permutation, creating RGB matrix, RGB to YCbCr transform and the secret sharing. The quality of the encrypted images are tested with visual inspection and evaluated with different quality measures. The performance of the proposed method is also evaluated by various testing methods.

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

    OpenAIRE

    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...

  3. Encryption of QR code and grayscale image in interference-based scheme with high quality retrieval and silhouette problem removal

    Science.gov (United States)

    Qin, Yi; Wang, Hongjuan; Wang, Zhipeng; Gong, Qiong; Wang, Danchen

    2016-09-01

    In optical interference-based encryption (IBE) scheme, the currently available methods have to employ the iterative algorithms in order to encrypt two images and retrieve cross-talk free decrypted images. In this paper, we shall show that this goal can be achieved via an analytical process if one of the two images is QR code. For decryption, the QR code is decrypted in the conventional architecture and the decryption has a noisy appearance. Nevertheless, the robustness of QR code against noise enables the accurate acquisition of its content from the noisy retrieval, as a result of which the primary QR code can be exactly regenerated. Thereafter, a novel optical architecture is proposed to recover the grayscale image by aid of the QR code. In addition, the proposal has totally eliminated the silhouette problem existing in the previous IBE schemes, and its effectiveness and feasibility have been demonstrated by numerical simulations.

  4. Image encryption schemes for joint photographic experts group and graphics interchange format formats based on three-dimensional baker with compound chaotic sequence generator

    Science.gov (United States)

    Ji, Shiyu; Tong, Xiaojun; Zhang, Miao

    2013-01-01

    We propose several methods to transplant the compound chaotic image encryption scheme with permutation based on three-dimensional (3-D) baker onto image formats such as the joint photographic experts group (JPEG) and graphics interchange format (GIF). The new methods avert the discrete cosine transform and quantization, which result in floating point precision loss, and succeed to encrypt and decrypt JPEG images lossless. The ciphered JPEG images generated by our solution own much better randomness than most other existing schemes. Our proposed method for GIF keeps the property of animation successfully. The security test results indicate the proposed methods have high security, and the speed of our algorithm is faster than classical solutions. Since JPEG and GIF image formats are popular contemporarily, we show that the prospect of chaotic image encryption is promising.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    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...

  9. Optical color image encryption based on an asymmetric cryptosystem in the Fresnel domain

    Science.gov (United States)

    Chen, Wen; Chen, Xudong

    2011-08-01

    In recent years, optical color image encryption has attracted much attention in the information security field. Some approaches, such as digital holography, have been proposed to encrypt color images, but the previously proposed methods are developed based on optical symmetric cryptographic strategies. In this paper, we apply an optical asymmetric cryptosystem for the color image encryption instead of conventional symmetric cryptosystems. A phase-truncated strategy is applied in the Fresnel domain, and multiple-wavelength and indexed image methods are further employed. The security of optical asymmetric cryptosystem is also analyzed during the decryption. Numerical results are presented to demonstrate the feasibility and effectiveness of the proposed optical asymmetric cryptosystem for color image encryption.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

  12. Image encryption and compression based on kronecker compressed sensing and elementary cellular automata scrambling

    Science.gov (United States)

    Chen, Tinghuan; Zhang, Meng; Wu, Jianhui; Yuen, Chau; Tong, You

    2016-10-01

    Because of simple encryption and compression procedure in single step, compressed sensing (CS) is utilized to encrypt and compress an image. Difference of sparsity levels among blocks of the sparsely transformed image degrades compression performance. In this paper, motivated by this difference of sparsity levels, we propose an encryption and compression approach combining Kronecker CS (KCS) with elementary cellular automata (ECA). In the first stage of encryption, ECA is adopted to scramble the sparsely transformed image in order to uniformize sparsity levels. A simple approximate evaluation method is introduced to test the sparsity uniformity. Due to low computational complexity and storage, in the second stage of encryption, KCS is adopted to encrypt and compress the scrambled and sparsely transformed image, where the measurement matrix with a small size is constructed from the piece-wise linear chaotic map. Theoretical analysis and experimental results show that our proposed scrambling method based on ECA has great performance in terms of scrambling and uniformity of sparsity levels. And the proposed encryption and compression method can achieve better secrecy, compression performance and flexibility.

  13. A joint asymmetric watermarking and image encryption scheme

    Science.gov (United States)

    Boato, G.; Conotter, V.; De Natale, F. G. B.; Fontanari, C.

    2008-02-01

    Here we introduce a novel watermarking paradigm designed to be both asymmetric, i.e., involving a private key for embedding and a public key for detection, and commutative with a suitable encryption scheme, allowing both to cipher watermarked data and to mark encrypted data without interphering with the detection process. In order to demonstrate the effectiveness of the above principles, we present an explicit example where the watermarking part, based on elementary linear algebra, and the encryption part, exploiting a secret random permutation, are integrated in a commutative scheme.

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

    OpenAIRE

    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 ...

  15. Halving the dimension of a single image to be encrypted optically to avoid data expansion

    Science.gov (United States)

    Yi, Jiawang; Tan, Guanzheng

    2016-06-01

    When directly applying optical transforms, such as fractional Fourier transform (FrFT), to a single image or real image (input image), the resulting image will become complex-valued, which leads to the doubling of data volume. This data expansion problem can be found in many existing single-image optical encryption schemes. We propose a folding technique to offset the data expansion by constructing a complex input image of half size. And we devise an optical single-image encryption scheme based on double FrFTs, in which this technique together with compressed sensing can bring about the possible maximum compression of encrypted images. Moreover, the chaos-based random circular shift for scrambling is introduced to enhance security. The chaotic random signum matrix is also tried as the measurement matrix, and it displays a good performance. Simulation results demonstrate the validity and security of the proposed scheme.

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

    Institute of Scientific and Technical Information of China (English)

    万玉晴

    2015-01-01

    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。%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.

  17. An RGB Image Encryption Supported by Wavelet-based Lossless Compression

    Directory of Open Access Journals (Sweden)

    Ch. Samson

    2012-09-01

    Full Text Available In this paper we have proposed a method for an RGB image encryption supported by lifting scheme based lossless compression. Firstly we have compressed the input color image using a 2-D integer wavelet transform. Then we have applied lossless predictive coding to achieve additional compression. The compressed image is encrypted by using Secure Advanced Hill Cipher (SAHC involving a pair of involutory matrices, a function called Mix( and an operation called XOR. Decryption followed by reconstruction shows that there is no difference between the output image and the input image. The proposed method can be used for efficient and secure transmission of image data.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

    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.

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

    OpenAIRE

    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...

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

    Science.gov (United States)

    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

  6. A novel chaotic map and an improved chaos-based image encryption scheme.

    Science.gov (United States)

    Zhang, Xianhan; Cao, Yang

    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.

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

    Science.gov (United States)

    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

  8. RESEARCH ON FAST IMAGE ENCRYPTION METHOD FOR MOBILE TERMINALS%移动终端的图像快速加密方法研究

    Institute of Scientific and Technical Information of China (English)

    赵戈; 万玉晴

    2015-01-01

    According to the requirements of intelligent terminals of mobile Internet in image encryption,this article puts forward the four selection principles in regard to encryption approaches for images of mobile terminals based on analysing the traditional methods of image pixel positions scrambling and pixel greyscale value encryption by transformation,and based on these principles we design the encryption algorithm with dual image keys and dual scrambling which combines the Arnold conversion and the chaotic sequence encryption.Meanwhile,in order to improve computing speed of encryption and decryption,and to realise fast image encryption and decryption of mobile terminals,based on periodic verification and theoretical derivation of Arnold conversion,we derive a fast look-up table method for image encryption and decryption matrix of mobile terminals.It is proved by application that the algorithm can satisfy the requirement of transaction processing in image encryption of mobile terminals.%针对移动互联网智能终端的图像加密需求,在对传统的图像像素位置置乱以及像素灰度值变换加密等方法的分析与实验基础上,提出移动终端图像加密方法的四项选择原则,并按此原则设计Arnold变换和混沌序列加密相结合的图像双重密钥双重置乱加密算法。同时,为了提高加解密运算速度,实现移动终端快速图像加解密工作,在基于对Arnold变换的周期性验证和理论推导,得出移动终端的图像加解密矩阵的快速查表法。应用证明,该算法能满足事务处理对移动终端图像加密的需求。

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

    Directory of Open Access Journals (Sweden)

    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

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    OpenAIRE

    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 ...

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

    OpenAIRE

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Medical Images Watermarking Algorithm Based on Improved DCT

    OpenAIRE

    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...

  15. Transmission Error and Compression Robustness of 2D Chaotic Map Image Encryption Schemes

    Directory of Open Access Journals (Sweden)

    Gschwandtner Michael

    2007-01-01

    Full Text Available This paper analyzes the robustness properties of 2D chaotic map image encryption schemes. We investigate the behavior of such block ciphers under different channel error types and find the transmission error robustness to be highly dependent on on the type of error occurring and to be very different as compared to the effects when using traditional block ciphers like AES. Additionally, chaotic-mixing-based encryption schemes are shown to be robust to lossy compression as long as the security requirements are not too high. This property facilitates the application of these ciphers in scenarios where lossy compression is applied to encrypted material, which is impossible in case traditional ciphers should be employed. If high security is required chaotic mixing loses its robustness to transmission errors and compression, still the lower computational demand may be an argument in favor of chaotic mixing as compared to traditional ciphers when visual data is to be encrypted.

  16. New Visual Cryptography Algorithm For Colored Image

    CERN Document Server

    Abdulla, Sozan

    2010-01-01

    Visual Cryptography is a special encryption technique to hide information in images, which divide secret image into multiple layers. Each layer holds some information. The receiver aligns the layers and the secret information is revealed by human vision without any complex computation. The proposed algorithm is for color image, that presents a system which takes four pictures as an input and generates three images which correspond to three of the four input pictures. The decoding requires only selecting some subset of these 3 images, making transparencies of them, and stacking them on top of each other, so the forth picture is reconstructed by printing the three output images onto transparencies and stacking them together. The reconstructed image achieved in same size with original secret image.

  17. Robust Encryption Algorithm Based Sht in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    Hukum Singh

    2015-01-01

    Full Text Available 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 overcoming the problem of axis alignment associated with an optical setup. The proposed encryption scheme is a lensless optical system and its digital implementation has been performed using MATLAB 7.6.0 (R2008a. The scheme has been validated for a grayscale and a binary image. The efficacy of the proposed scheme is verified by computing mean-squared-error (MSE between the recovered and the original images. We have also investigated the scheme’s sensitivity to the encryption parameters and examined its robustness against occlusion and noise attacks.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    OpenAIRE

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Science.gov (United States)

    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

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

    Institute of Scientific and Technical Information of China (English)

    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.

  7. Optical encryption of unlimited-size images based on ptychographic scanning digital holography.

    Science.gov (United States)

    Gao, Qiankun; Wang, Yali; Li, Tuo; Shi, Yishi

    2014-07-20

    The ptychographic scanning operation is introduced into digital holography to expand the field-of-view (FOV). An optical image encryption method based on this technique is further proposed and analyzed. The plaintext is moved sequentially in the way of ptychographic scanning and corresponding pairs of phase-shifted interferograms are recorded as ciphertexts. Then the holographic processing and the ptychographic iterative reconstruction are both employed to retrieve the plaintext. Numerical experiments demonstrate that the proposed system possesses high security level and wide FOV. The proposed method might also be used for other potential applications, such as three-dimensional information encryption and image hiding.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  14. 基于Chen系统的DSP混沌图像加密%DSP Chaotic image encryption based on Chen system

    Institute of Scientific and Technical Information of China (English)

    何丹; 李敬园

    2013-01-01

    介绍了在DSP基础上,实现数字图像的混沌加密及硬件实现方法.根据离散化和数字化处理技术,对三维Chen混沌系统作离散化处理,用C语言和DSP技术产生三维Chen混沌迭代序列,分别对数字图像进行混沌加密和解密.基于芯片型号为TMS32 0VC5509A的DSP开发平台,以灰度图像为例,设计了Chen混沌序列对数字图像进行加密与解密算法,给出了DSP硬件实现结果表明,改善了安全性、提高了速度、满足了实时性要求.%A novel method for realizing chaotic digital image encryption and its hardware implementation based on DSP is presented. By the discrete and digital process technology, the three-dimensional Chen chaotic system is made discrete and Chen chaotic iteration sequence is generated by using Hardware Description Language C and DSP technology.Red,green,and blue tricolor signals of the image are encrypted and decrypted, respectively .On the basis of the DSP exploitation platform with TMS320VC55O9A chip.a gray image with an BMP format is taken as an example. The digital image encryption and decryption algorithm using Chen chaotic sequence is designed,and DSP hardware implementation result is given.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  16. An Adaptive Blind Watermarking Algorithm for Color Image

    Directory of Open Access Journals (Sweden)

    Qiming Liu

    2013-01-01

    Full Text Available This paper proposed a novel blind color digital watermarking algorithm based on Integer Discrete Wavelet Transform (IDWT and Human Visual System (HVS. Firstly, color watermark image was processed into one dimension digital information, and color host image was converted into YIQ color space. Then, according to the features of HVS, encrypted watermark was embedded adaptively into the Y luminance component of the YIQ color space in IDWT domain. The proposed algorithm allowed extracting watermark without the help of original watermark and host image. Experiment results show that the embedded watermark is invisible and robust against common image attacks. 

  17. Efficient transmission of 1D and 2D chaotic map encrypted images with orthogonal frequency division multiplexing

    Science.gov (United States)

    Kasem, Hossam M.; Nasr, Mohamed E.; Sallam, Elsayed A.; Abd El-Samie, F. E.

    2011-10-01

    Image transmission takes place as an important research branch in multimedia broadcasting communication systems in the last decade. Our paper presents image transmission over a FFT-OFDM (Fast Fourier Transform Orthogonal Frequency Division Multiplexing). The need for encryption techniques increase with the appearance of the expression which said that our world became small village, and the use of image application such as conference and World Wide Web which increase rapidly in recent years. Encryption is an effective method for protecting the transmitted data by converting it into a form being invisible over transmission path and visible in receiver side. This paper presents a new hybrid encryption technique based on combination of Backer maps and logistic map. This proposed technique aims to increase PSNR and reduce the noise in the received image. The encryption is done by shuffling the positions of a pixel image using two dimensional Baker maps then encrypt using XOR operation with logistic map to generate cipher image over orthogonal frequency multiplexing (OFDM). The encryption approach adopted in this paper is based on chaotic Baker maps because the encoding and decoding steps in this approach are simple and fast enough for HDTV applications. The experimental results reveal the superiority of the proposed chaotic based image encryption technique using two logistic maps and two dimensional Backer map over normal Backer map.

  18. Application of input amplitude masks in image encryption with spatially incoherent illumination for increase of decrypted images signal-to-noise ratio

    Science.gov (United States)

    Cheremkhin, Pavel A.; Evtikhiev, Nikolay N.; Krasnov, Vitaly V.; Molodtsov, Dmitriy Y.; Rodin, Vladislav G.; Shifrina, Anna V.

    2016-04-01

    The majority of existing methods of optical encryption use not only light intensity distribution, easily registered with photosensors, but also its phase distribution. This provides best encryption strength for fixed quantities of elements and phase levels in a mask. Downsides are holographic registration scheme used in order to register not only light intensity distribution but also its phase distribution and speckle noise occurring due to coherent illumination. That factors lead to very poor decryption quality when it comes from computer simulations to optical implementations. Method of optical encryption with spatially incoherent illumination does not have drawbacks inherent to coherent systems, however, as only light intensity distribution is considered, mean value of image to be encrypted is always above zero which leads to intensive zero spatial frequency peak in image spectrum. Therefore, in case of spatially incoherent illumination, image spectrum, as well as encryption key spectrum, cannot be white. If encryption is based on convolution operation, no matter coherent light used or not, Fourier spectrum amplitude distribution of encryption key should overlap Fourier spectrum amplitude distribution of image to be encrypted otherwise loss of information is unavoidable. Another factor affecting decrypted image quality is original image spectrum. Usually, most part of image energy is concentrated in area of low frequencies. Consequently, only this area in encrypted image contains information about original image, while other areas contain only noise. We propose to use additional encoding of input scene to increase size of the area containing useful information. This provides increase of signal-to-noise ratio in encrypted image and consequentially increases quality of decrypted images. Results of computer simulations of test images optical encryption with spatially incoherent illumination and additional input amplitude masks are presented.

  19. An authenticated image encryption scheme based on chaotic maps and memory cellular automata

    Science.gov (United States)

    Bakhshandeh, Atieh; Eslami, Ziba

    2013-06-01

    This paper introduces a new image encryption scheme based on chaotic maps, cellular automata and permutation-diffusion architecture. In the permutation phase, a piecewise linear chaotic map is utilized to confuse the plain-image and in the diffusion phase, we employ the Logistic map as well as a reversible memory cellular automata to obtain an efficient and secure cryptosystem. The proposed method admits advantages such as highly secure diffusion mechanism, computational efficiency and ease of implementation. A novel property of the proposed scheme is its authentication ability which can detect whether the image is tampered during the transmission or not. This is particularly important in applications where image data or part of it contains highly sensitive information. Results of various analyses manifest high security of this new method and its capability for practical image encryption.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  2. System for Information Encryption Implementing Several Chaotic Orbits

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    OpenAIRE

    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...

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

    Institute of Scientific and Technical Information of China (English)

    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.

  8. Optical interference-based multiple-image encryption using spherical wave illumination and gyrator transform.

    Science.gov (United States)

    Abuturab, Muhammad Rafiq

    2014-10-10

    A new optical interference-based multiple-image encryption using spherical wave illumination and gyrator transform is proposed. In this proposal, each secret color image is divided into normalized red, green, and blue component images and independently encoded into corresponding phase-only component images. Then each phase-only component image of all the images are combined together to produce a single-phase-only component image as an input component image, which is bounded with a random phase mask to form a complex image. The two phase-only masks are analytically obtained from the inverse Fourier transformation of the complex image. The host image is chosen as the first phase-only mask, and the complex image hidden in the host image is regarded as the second phase-only mask. The spherical wave is generated to simultaneously illuminate phase-only masks. Then two modulated masks are gyrator transformed. The corresponding transformed images are phase truncated to obtain encrypted images and amplitude truncated to construct decryption keys. The decryption keys, angles of gyrator transform, wavelength and radius of the spherical wave, and individual decryption keys for authorized users are sensitive keys, which enhance the security layers of the system. The proposed system can be implemented by using optoelectronic architecture. Numerical simulation results demonstrate the flexibility of the system.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    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...

  13. Comparative Analysis of LEON 3 and NIOS II Processor Development Environment: Case Study Rijindael’s Encryption Algorithm

    Directory of Open Access Journals (Sweden)

    Meghana Hasamnis

    2012-06-01

    Full Text Available Embedded system design is becoming complex day by day, combined with reduced time-to-market deadlines. Due to the constraints and complexity in the design of embedded systems, it incorporates hardware / software co-design methodology. An embedded system is a combination of hardware and software parts integrated together on a common platform. A soft-core processor which is a hardware description language (HDL model of a specific processor (CPU can be customized for any application and can be synthesized for FPGA target. This paper gives a comparative analysis of the development environment for embedded systems using LEON 3 and NIOS II Processor, both soft core processors. LEON3 is an open source processor and NIOS II is a commercial processor. Case study under consideration is Rijindael’s Encryption Algorithm (AES. It is a standard encryption algorithm used to encrypt huge bulk of data and for security. Using the co-design methodology the algorithm is implemented on two different platforms. One using the open source and other using the commercial processor and the comparative results of the two different platforms is stated in terms of its performance parameters. The algorithm is partitioned in hardware and software parts and integrated on a common platform.

  14. Multimedia encryption and watermarking encryption and watermarking

    CERN Document Server

    Furht, Borko; Socek, Daniel

    2006-01-01

    ""Multimedia Encryption and Watermarking"" presents a comprehensive survey of contemporary multimedia encryption and watermarking techniques, which enable a secure exchange of multimedia intellectual property. Part I, Digital Rights Management (DRM) for Multimedia, introduces DRM concepts and models for multimedia content protection, and presents the key players. Part II, Multimedia Cryptography, provides an overview of modern cryptography, with the focus on modern image, video, speech, and audio encryption techniques. This book also provides an advanced concept of visual and audio sharing tec

  15. Security of image encryption scheme based on multi-parameter fractional Fourier transform

    Science.gov (United States)

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

    2016-10-01

    Recently, multi-parameter fractional Fourier transform (MPFRFT) has been widely applied in the optics cryptosystem, which has attracted more and more researchers' attention. However, in further study we find a serious security problem on the MPFRFT which is the multi-choice of decryption key corresponding to an encryption key. The existence of multi-decryption-key hinders the application of this algorithm. We present a new generalized fractional Fourier transform, which can overcome the problem and enlarge the key space. The simulation results show that the proposed algorithm has higher security and key sensitivity.

  16. Image encryption and authentication. A fully digital approach

    International Nuclear Information System (INIS)

    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

  17. Optical image encryption with silhouette removal based on interference and phase blend processing

    Science.gov (United States)

    Wang, Qu

    2012-10-01

    To completely eliminate the silhouette problem that inherently exists in the earlier interference-based encryption scheme with two phase-only masks (POMs), we propose a simple new encryption method based on optical interference of one random POM and two analytically obtained POMs. Different from the previous methods which require time-consuming iterative computation or postprocessing of the POMs for silhouette removal, our method can resolve the problem during the production of the POMs based on interference principle. Information associated with the original image is smoothed away by modulation of the random POM. Illegal deciphers cannot retrieve the primitive image using only one or two of the POMs. Incorporated with the linear phase blend operation, our method can provide higher robustness against brute force attacks. Simulation results are presented to support the validity and feasibility of our method.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  19. Medical Images Watermarking Algorithm Based on Improved DCT

    Directory of Open Access Journals (Sweden)

    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

  20. An Algorithm of Lorenz Chaotic Encryption Audio Watermarking Based on DWT%基于Lorenz混沌加密的DWT音频水印算法

    Institute of Scientific and Technical Information of China (English)

    陈雪松; 申美玲

    2011-01-01

    将混沌理论引入音频水印系统的设计中,提出一种基于Lorenz混沌系统的小波域数字音频水印算法.先将图像水印进行Logistic混沌加密,再利用三维Lorenz混沌吸引子在一定初值条件下产生的矩阵二次加密图像水印.把加密后的水印图像作为载体嵌入音频信号的小波域.因为高维混沌的系统结构更为复杂、不可预测性更强,若没有初始值便无法得到加密矩阵,因此保障了水印的安全性;而在水印检测时,只要提供混沌加密的密钥和产生加密矩阵的初始值,就可完成水印的提取.仿真实验采用多种攻击方法,证明此方法具有很强的安全性和鲁棒性.%A methodology for increasing audio watermark robustness based on Lorenz chaotic system was presented.A binary image watermarking was encrypted by a chaotic sequence and a matrix which was generated by Lorenz chaotic attractor depending on the initial data.The digital encrypted image could be embedded in the original signal wavelet domain in the algorithm.Because the high-dimensional chaotic system structure was more complex and unpredictable, only having the initial value of the matrix could be encrypted, the security of the watermark was protected.As long as the chaotic encryption keys and the initial value were provided, watermark extraction could be completed in watermark detection.The experimental results using a variety of attack methods show that the watermarks are imperceptible and the algorithm is robust.

  1. Permutation Code Encryption-New Achievement Based on Path Encryption

    Institute of Scientific and Technical Information of China (English)

    WU Jinmu; LIU Maohua; FU Guiqin; GUO Lina

    2006-01-01

    By researching into the attack to present block cipher, we find an essential reason leading to the assailable encryption strength, set up a new block cipher idea and put forward a block cipher encryption concept path encryption. We present permutation code encryption which is based on path encryption. Now permutation code encryption is a patent of Chinese invention. In Permutation Code Encryption, we use a pseudo-random sequence of the keys to control the paths. The simulation result shows that for n-bit block the encryption strength is novel higher than 2n and the algorithm can finish the encryption of one block in 7.5 ns, which is unrelated with the block length.

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

    Institute of Scientific and Technical Information of China (English)

    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

  3. Multiple-image encryption using polarized light encoding and the optical interference principle in the Fresnel-transform domain.

    Science.gov (United States)

    Wang, Qu; Guo, Qing; Zhou, Jinyun

    2013-12-20

    We propose a multiple-image encryption scheme, based on polarized light encoding and the interference principle of phase-only masks (POMs), in the Fresnel-transform (FrT) domain. In this scheme, each secret image is converted into an intensity image by polarized light encoding, where a random key image and a pixilated polarizer with random angles are employed as keys. The intensity encrypted images produced by different secret images are convolved together and then inverse Fresnel-transformed. Phase and amplitude truncations are used to generate the asymmetric decryption keys. The phase-truncated inverse FrT spectrum is sent into an interference-based encryption (IBE) system to analytically obtain two POMs. To reduce the transmission and storage load on the keys, the chaotic mapping method is employed to generate random distributions of keys for encryption and decryption. One can recover all secret images successfully only if the corresponding decryption keys, the mechanism of FrTs, and correct chaotic conditions are known. The inherent silhouette problem can be thoroughly resolved by polarized light encoding in this proposal, without using any time-consuming iterative methods. The entire encryption and decryption process can be realized digitally, or in combination with optical means. Numerical simulation results are presented to verify the effectiveness and performance of the proposed scheme.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  5. 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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. Image encryption based on the reality-preserving multiple-parameter fractional Fourier transform and chaos permutation

    Science.gov (United States)

    Lang, Jun

    2012-07-01

    In recent years, a number of methods have been proposed in the literature for the encryption of two-dimensional information by use of the fractional Fourier transform, but most of their encryptions are complex value and need digital hologram technique to record their encrypted information, which is inconvenience for digital transmission. In this paper, we first propose a novel reality-preserving multiple-parameter fractional Fourier transform which share real-valuedness outputs as well as most of the properties required for a fractional transform. Then we propose a new approach for image encryption based on the real-valuedness of the reality-preserving multiple-parameter fractional Fourier transform and the decorrelation property of chaotic maps in order to meet the requirements of the secure image transmission. In the proposed scheme, the image is encrypted by juxtaposition of sections of the image in the reality-preserving multiple-parameter fractional Fourier domains and the alignment of sections is determined by chaotic logistic maps. Numerical simulations are performed to demonstrate that the proposed method is reliable and more robust to blind decryption than several existing methods.

  8. 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

    Institute of Scientific and Technical Information of China (English)

    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。

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

    OpenAIRE

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2015-10-27

    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.

  14. Research on image self-recovery algorithm based on DCT

    Directory of Open Access Journals (Sweden)

    Shengbing Che

    2010-06-01

    Full Text Available Image compression operator based on discrete cosine transform was brought up. A securer scrambling locational operator was put forward based on the concept of anti-tamper radius. The basic idea of the algorithm is that it first combined image block compressed data with eigenvalue of image block and its offset block, then scrambled or encrypted and embeded them into least significant bit of corresponding offset block. This algorithm could pinpoint tampered image block and tampering type accurately. It could recover tampered block with good image quality when tamper occured within the limits of the anti-tamper radius. It could effectively resist vector quantization and synchronous counterfeiting attacks on self-embedding watermarking schemes.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  18. FORTRAN Algorithm for Image Processing

    Science.gov (United States)

    Roth, Don J.; Hull, David R.

    1987-01-01

    FORTRAN computer algorithm containing various image-processing analysis and enhancement functions developed. Algorithm developed specifically to process images of developmental heat-engine materials obtained with sophisticated nondestructive evaluation instruments. Applications of program include scientific, industrial, and biomedical imaging for studies of flaws in materials, analyses of steel and ores, and pathology.

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

    OpenAIRE

    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.

  20. Combination of Hybrid Chaotic Encryption and LDPC for Secure Transmission of Images over Wireless Networks

    Directory of Open Access Journals (Sweden)

    Mona F. M. Mursi

    2014-11-01

    Full Text Available Robust and secure transmission strategy for high quality image through wireless networks is considered a great challenge. However, the majority of encrypted image transmission schemes don't consider well the effect of bit errors occurring during transmission. These errors are due to the factors that affect the information such as noise and multipath propagation. That should be handled by an efficient channel coding scheme. Our proposed scheme is based on combining hybrid chaotic encryption, which is based on two-dimensional chaotic maps which is utilized for data security, with an error correction technique based on the Low Density Parity Check (LDPC code. The LDPC is employed as channel coding for data communication in order to solve the problem of the channel’s limited bandwidth and improve throughput. Simulation results show that the proposed scheme achieves a high degree of robustness against channel impairments and wide varieties of attacks as wells as improved reliability of the wireless channel. In addition, LDPC is utilized for error correction in order to solve the limitations of wireless channels.

  1. Multiple-image encryption by space multiplexing based on compressive sensing and the double-random phase-encoding technique.

    Science.gov (United States)

    Deepan, B; Quan, C; Wang, Y; Tay, C J

    2014-07-10

    In this paper, a new multiple-image encryption and decryption technique that utilizes the compressive sensing (CS) concept along with a double-random phase encryption (DRPE) has been proposed. The space multiplexing method is employed for integrating multiple-image data. The method, which results in a nonlinear encryption system, is able to overcome the vulnerability of classical DRPE. The CS technique and space multiplexing are able to provide additional key space in the proposed method. A numerical experiment of the proposed method is implemented and the results show that the proposed method has good accuracy and is more robust than classical DRPE. The proposed system is also employed against chosen-plaintext attacks and it is found that the inclusion of compressive sensing enhances robustness against the attacks.

  2. Decryption of pure-position permutation algorithms

    Institute of Scientific and Technical Information of China (English)

    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. Uncertain state encryption algorithm based on linear congruential sequence%基于线性同余的不定态结果加密算法

    Institute of Scientific and Technical Information of China (English)

    王思乐; 卢素魁; 杨文柱

    2012-01-01

    The traditional encryption algorithms is often more complex and difficult to master, complex algorithms tend to greatly increase the complexity of the program, the same encryption algorithm results are the same and reduce the resistance to crack the encryption result ability. After the linear congruential sequences data on study characteristics as well as in practice after long time exploration and detection based on linear congruential sequences, this paper puts forward a practical method of encryption, simple, easy to realize; as far as possible without loss of intensity of encryption cases to improve the encryption speed, at the same time, the same input encryption results the output of different, some extent increase the anti crack capacity.%传统的加密算法往往比较复杂而难以掌握,复杂的算法往往大大增加程序的复杂度,同一算法加密结果不变又降低了加密结果的抗破解能力.经过对线性同余序列数据特征的研究以及在实践中经过长时间摸索与检测,基于线性同余序列提出了一种实用的加密方法,简单、容易实现;在尽量不损失加密强度的情况下提高了加解密速度,同时,同一输入得到的加密结果输出不同,一定程度上增强了抗破解能力.

  4. Assessing the performance of a method of simultaneous compression and encryption of multiple images and its resistance against various attacks.

    Science.gov (United States)

    Alfalou, A; Brosseau, C; Abdallah, N; Jridi, M

    2013-04-01

    We introduce a double optimization procedure for spectrally multiplexing multiple images. This technique is adapted from a recently proposed optical setup implementing the discrete cosine transformation (DCT). The new analysis technique is a combination of spectral fusion based on the properties of DCT, specific spectral filtering, and quantization of the remaining encoded frequencies using an optimal number of bits. Spectrally multiplexing multiple images defines a first level of encryption. A second level of encryption based on a real key image is used to reinforce encryption. A set of numerical simulations and a comparison with the well known JPEG (Joint Photographic Experts Group) image compression standard have been carried out to demonstrate the improved performances of this method. The focus here will differ from the method of simultaneous fusion, compression, and encryption of multiple images (SFCE) [Opt. Express 19, 24023 (2011)] in the following ways. Firstly, we shall be concerned with optimizing the compression rate by adapting the size of the spectral block to each target image and decreasing the number of bits required to encode each block. This size adaptation is achieved by means of the root-mean-square (RMS) time-frequency criterion. We found that this size adaptation provides a good tradeoff between bandwidth of spectral plane and number of reconstructed output images. Secondly, the encryption rate is improved by using a real biometric key and randomly changing the rotation angle of each block before spectral fusion. By using a real-valued key image we have been able to increase the compression rate of 50% over the original SFCE method. We provide numerical examples of the effects for size, rotation, and shifting of DCT-blocks which play noteworthy roles in the optimization of the bandwidth of the spectral plane. Inspection of the results for different types of attack demonstrates the robustness of our procedure.

  5. 关于加密数据的填充方式的研究%Study on mode and padding in encryption algorithm

    Institute of Scientific and Technical Information of China (English)

    樊志英

    2014-01-01

    Aiming at the interoperability of encryption and decryption in different platform environment,the two important parameters which are encryption mode and padding method used in encryption algorithm are elaborated in combination with en-cryption function Cipher provided by the encryption extended service on the Java platform. The rules in the encryption mode are discussed in detail,and their advantages,disadvantages and application scope are compared. The difference between the plain-text data before and after padding is analyzed in depth,which can narrow the range of encryption and decryption parameters for Java and other platforms,and can effectively solve the interaction problem between encryption and decryption.%针对不同平台环境下加解密的互通问题,结合Java平台下密码扩展服务SunJCE提供的加密类函数Cipher,对加密算法中使用到的明文填充方式进行阐述。详细介绍加密时明文数据的常用填充规则,并比较数据填充前后的区别,深入分析SunJCE支持的填充方式与常用填充规则的对应性,并对RSA算法的加解密互通进行了测试。加密数据填充方式的研究,为Java平台与其他平台之间加解密参数的约定提供了依据。双方只有遵循相同的填充和去填充规则,才能实现有效的解密。

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

    KAUST Repository

    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.

  7. Speckle imaging algorithms for planetary imaging

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. 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

    Institute of Scientific and Technical Information of China (English)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  12. New Comprehensive Study to Assess Comparatively the QKD, XKMS, KDM in the PKI encryption algorithms

    Directory of Open Access Journals (Sweden)

    Bilal Bahaa Zaidan

    2009-11-01

    Full Text Available Protecting data is a very old art and wide use since the Egyptian when they identify the 1st encryption method in this world, the spiciest people categorize protecting data under computer forensic and others locate it under network security, cryptography methods are the backbone of this art, nowadays many of new techniques for the attacker's beings develops, a lot of methods for information protecting start dropping down such as RSA and stander encryption methods, in the same time a new methods has been appeared such as Quantum cryptography, the new methods has faced problems in the key distribution or key management and some time such as RSA there is a function may estimate the keys, In this paper we will make a comparative study between the key management distribution methods, in fact we will talk about QKD Encryption in the fiber optic area vice verse the KDM in the normal networks, for instant there are two known methods, KDM "Diffi- Hellman" and XKMS.

  13. An 3-DES Key Encryption Method Generated by Iris Image%由虹膜图像生成3-DES密钥的加密方法

    Institute of Scientific and Technical Information of China (English)

    曾明权; 卞燕山; 赵刚

    2012-01-01

    介绍虹膜生物特征生成密钥的过程,在此基础上,采用3-DES算法对机密图像进行加密。图像加密方案中,将生物特征技术引入其中,成功获得了所需要的比特位,通过对128比特位进行处理,得到了3-DES算法所需要的密钥,其试验结果表明加密的结果良好,达到了预期的目的。%The progresses that biological characteristics of iris are untilized to generate key are presented, based on which 3-DES algorithm is employed for confidential image encryption. The biological characteristics are introduced into image encryption methods and the needed bits stream are archived. After disposing those 128 bits stream, we attain the key for 3-DES algorithm. Experiments show that the enctyption result is good and prospective target is realized.

  14. Optical multiple-image encryption based on the chaotic structured phase masks under the illumination of a vortex beam in the gyrator domain.

    Science.gov (United States)

    Liansheng, Sui; Bei, Zhou; Xiaojuan, Ning; Ailing, Tian

    2016-01-11

    A novel multiple-image encryption scheme using the nonlinear iterative phase retrieval algorithm in the gyrator transform domain under the illumination of an optical vortex beam is proposed. In order to increase the randomness, the chaotic structured phase mask based on the logistic map, Fresnel zone plate and radial Hilbert mask is proposed. With the help of two chaotic phase masks, each plain image is encoded into two phase-only masks that are considered as the private keys by using the iterative phase retrieval process in the gyrator domain. Then, the second keys of all plain images are modulated into the ciphertext, which has the stationary white noise distribution. Due to the use of the chaotic structured phase masks, the problem of axis alignment in the optical setup can easily be solved. Two private keys are directly relative to the plain images, which makes that the scheme has high resistance against various potential attacks. Moreover, the use of the vortex beam that can integrates more system parameters as the additional keys into one phase mask can improve the security level of the cryptosystem, which makes the key space enlarged widely. Simulation results are given to verify the feasibility and robustness of the proposed encryption scheme.

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

    Science.gov (United States)

    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.

  16. Imaging algorithms in radio interferometry

    CERN Document Server

    Sault, R J

    2007-01-01

    The paper reviews progress in imaging in radio interferometry for the period 1993-1996. Unlike an optical telescope, the basic measurements of a radio interferometer (correlations between antennas) are indirectly related to a sky brightness image. In a real sense, algorithms and computers are the lenses of a radio interferometer. In the last 20 years, whereas interferometer hardware advances have resulted in improvements of a factor of a few, algorithm and computer advances have resulted in orders of magnitude improvement in image quality. Developing these algorithms has been a fruitful and comparatively inexpensive method of improving the performance of existing telescopes, and has made some newer telescopes possible. In this paper, we review recent developments in the algorithms used in the imaging part of the reduction process. What constitutes an `imaging algorithm'? Whereas once there was a steady `forward' progression in the reduction process of editing, calibrating, transforming and, finally, deconvolv...

  17. Double image encryption based on phase-amplitude mixed encoding and multistage phase encoding in gyrator transform domains

    Science.gov (United States)

    Wang, Qu; Guo, Qing; Lei, Liang

    2013-06-01

    We present a novel method for double image encryption that is based on amplitude-phase mixed encoding and multistage random phase encoding in gyrator transform (GT) domains. In the amplitude-phase mixed encoding operation, a random binary distribution matrix is defined to mixed encode two primitive images to a single complex-valued image, which is then encrypted into a stationary white noise distribution by the multistage phase encoding with GTs. Compared with the earlier methods that uses fully phase encoding, the proposed method reduces the difference between two primitive images in key space and sensitivity to the GT orders. The primitive images can be recovered exactly by applying correct keys with initial conditions of chaotic system, the GT orders and the pixel scrambling operation. Numerical simulations demonstrate that the proposed scheme has considerably high security level and certain robustness against data loss and noise disturbance.

  18. Simultaneous nonlinear encryption of grayscale and color images based on phase-truncated fractional Fourier transform and optical superposition principle.

    Science.gov (United States)

    Wang, Xiaogang; Zhao, Daomu

    2013-09-01

    A nonlinear color and grayscale images cryptosystem based on phase-truncated fractional Fourier transform and optical superposition principle is proposed. In order to realize simultaneous encryption of color and grayscale images, each grayscale image is first converted into two phase masks by using an optical coherent superposition, one of which is treated as a part of input information that will be fractional Fourier transformed while the other in the form of a chaotic random phase mask (CRPM) is used as a decryption key. For the purpose of optical performance, all the processes are performed through three channels, i.e., red, green, and blue. Different from most asymmetric encryption methods, the decryption process is designed to be linear for the sake of effective decryption. The encryption level of a double random phase encryption based on phase-truncated Fourier transform is enhanced by extending it into fractional Fourier domain and the load of the keys management and transmission is lightened by using CRPMs. The security of the proposed cryptosystem is discussed and computer simulation results are presented to verify the validity of the proposed method.

  19. Testing a Variety of Encryption Technologies

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    乔中良

    2015-01-01

    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 the example show that the algorithm has the advantages of the greater embedded capacity, and more flexible operation.%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

  1. 基于手指静脉特征图像的加密研究%Research on Encryption Based on Finger Vein Feature Image

    Institute of Scientific and Technical Information of China (English)

    陈暄

    2016-01-01

    Information security in the mobile Internet is currently a hotspot in researches.Starting from encryption of finger vein image, this paper first extracts characteristics of the finger vein image,and gets the size of vein image through establishing image smoother as well as the collected image of vein features through selecting the darkness area and characteristic features.Then,this paper adopts the function based on wavelet,Android mapping,the quadratic Logistic mapping and Baker transform to encrypt the vein image.Conduct experiment to com-pare the correlation analysis and differential attack analysis,and the results show that algorithm in this paper is safe and costs less time,so it is suitable to promote it in the mobile Internet.%移动互联下的信息安全是目前研究的热门,提出从手指静脉图像的加密出发,首先对手指静脉图像的特征进行了提取,通过构建图像平滑器来获得静脉图像的大小,明暗区域的选择和特征图像的加强来获得采集后的静脉特征图像,其次对静脉图像采用基于小波基函数,Arnold映射,二次Logistic 映射和Baker变换的混合加密方式对进行加密;在相关系分析和差分攻击分析等方面实验比较,说明算法具有很好的安全性和低耗时性,能够完全适应在移动互联环境中推广。

  2. Opto-digital spectrum encryption by using Baker mapping and gyrator transform

    Science.gov (United States)

    Chen, Hang; Zhao, Jiguang; Liu, Zhengjun; Du, Xiaoping

    2015-03-01

    A concept of spectrum information hidden technology is proposed in this paper. We present an optical encryption algorithm for hiding both the spatial and spectrum information by using the Baker mapping in gyrator transform domains. The Baker mapping is introduced for scrambling the every single band of the hyperspectral image before adding the random phase functions. Subsequently, three thin cylinder lenses are controlled by PC for implementing the gyrator transform. The amplitude and phase information in the output plane can be regarded as the encrypted information and main key. Some numerical simulations are made to test the validity and capability of the proposed encryption algorithm.

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

    Science.gov (United States)

    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

  4. Optical Encryption with Jigsaw Transform using Matlab

    CERN Document Server

    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.

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

    OpenAIRE

    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...

  6. Research on Optimizing of Encryption Algorithm to Network Communication%网络通信中加密算法优化仿真研究

    Institute of Scientific and Technical Information of China (English)

    李志刚

    2011-01-01

    Research network security encryption problem. In order to protect the security of network communication and information, the communication message information encryption is necessary. But when communication network is attacked, partial communication message is intercepted and vice versa. Traditional AES encryption algorithm in which encryption and decryption used the same keys, can not effectively prevent the cyber attacks and interceptions of messages, leading to the problem that network communication safety is not high. This paper put forward an improved Rijndael method, by using random depth first searching algorithm, different paths were chosen to identify different encrypted data. Different keys were used for encryption and decryption to reduce the rate of crack message, avoiding the problem that encryption and decryption share the same key will result weak ability of anti - attack. Experiments show that the improved algorithm has stronger anti - interference ability and can strengthen the network security effectively.%研究网络通信中的加密问题,提高网络通信安全性.针对保护网络通信信息安全,需要对通信报文信息进行密钥加密,但是当通信受到网络攻击时部分通信报文被截取并破译,加密和解密都使用同一密钥的传统AES加密算法,无法有效阻止网络攻击对报文的截取、破译,造成网络通信安全性不高的问题.为解决上述问题,提出一种改进的Rijndael算法,通过随机深度优先搜索算法,在初始节点与目的节点之间选择不同的路径标识不同加密数据,对加密和解密使用不同的密钥来降低报文的破译率,避免加密和解密共用一个密钥而造成的对网络攻击的抗击性不强的问题.实验表明,改进的算法对网络攻击的抗干扰能力得到了增强,并对加强网络安全提供了有效的保障.

  7. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  8. Advanced Imaging Algorithms for Radiation Imaging Systems

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

  10. Signature Encryption Algorithm Based on Mobile Phone Payment%基于签名加密算法的手机支付

    Institute of Scientific and Technical Information of China (English)

    王斌

    2014-01-01

    信息技术不断的发展过程中,对于信息安全的管理模式就是人们最为关心的问题。如何在安全的环境进行金融管理交易,如何使用更好的加密算法保证网络信息的安全,这些都是本文需要讨论的话题。在通过多曲线的密码的机制功能下,选用不对称的加密方式,设计处理一种签名的加密算法来保证手机支付的安全。这项机制功能也是在密钥信息数字化的基础上增加了签名功能,有效的结合了密码的加密解密功能为一体。算法的加密功能有效的保证了手机支付的安全性和稳定性。%The development of information technology, the most concerned problem for information security management mode is the people. How to carry out financial management transactions in a safe environment, encryption algorithm to use a bet-ter guarantee the security of network information, these are the need to discuss the topic. In the function mechanism of the curve of the password, use asymmetric encryption, designed to handle a signature encryption algorithm to ensure the mobile phone pay-ment security. The function of this mechanism is also increased the signature function based on the digital key information, effec-tively combines the password encryption and decryption functions. Encryption function effectively guarantee the mobile phone payment security and stability.

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

    OpenAIRE

    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 ...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    CERN Document Server

    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.

  14. Image hiding algorithm based on block random scrambling and grayscale transformation

    Science.gov (United States)

    Chen, Yuefen; Lin, Junhuan; Zhang, Shiqing; Chen, Caiming

    2010-07-01

    A new image scrambling algorithm is proposed in this paper. The secret image is encrypted by both random scrambling based on blocks and grayscale transformation based on a pseudo-random sequence, using two keys respectively. The information embedding is implemented in the space domain through replacing the low four bits of the host image pixels with the high four bits of the secret image pixels. A simple system of image hiding and extraction using the proposed algorithm based on Matlab is realized, and its resistance to noising and cropping is analyzed Simulation results show that the proposed algorithm can extract the hided image without knowing the host image information, and has the advantages of simple implementation, large hiding capacity and good safety performance.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  16. Military Image Encryption Hidden Information Identification Technology Research%图像加密隐藏信息识别技术研究

    Institute of Scientific and Technical Information of China (English)

    郝夏斐; 牛红惠

    2012-01-01

    The military encryption image hiding information accurately identify technology, In the military the image of the encrypted information hiding in the picture if the noise, the noise signal and information hiding sensitive signal mixed together, will cause the hidden information sensitive signal deform spectroscopic characteristics. More than traditional algorithm is through the acquisition of image of sensitive information map features can identify the completion of the inspection, noise signal and information hiding mix together, cause hidden information map can identify when deformed features, cause identification accuracy decline. Put forward a kind of reverse hidden transform algorithm military image hidden information identification technology, scrambling to military image processing, the use of interference clear finish recognition technology. Experiments show that the algorithm can avoid the noise signal and the hidden cause of mixed signal characteristics hidden information deform defects, ensure the military image hiding information identification accuracy%研究加密图像隐藏信息准确识别技术.在图像中,如果加密信息隐藏在图片的噪声中,噪声信号和隐藏信息敏感信号混合在一起,将造成隐藏信息的敏感信号图谱特征发生形变.传统算法多是通过采集图像中的敏感信息图谱特征完成检测的,噪声信号和隐藏信息混合在一起,造成隐藏信息图谱可识别特征发生突变,导致识别准确率下降.提出一种逆向隐藏变换算法的图像隐藏信息识别技术,对图像进行置乱处理,运用干扰清除技术完成识别.实验证明,这种算法能够避免由于噪声信号和隐藏信号混合造成的隐藏信息特征发生形变的缺陷,保证了图像隐藏信息识别的准确率.

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

    International Nuclear Information System (INIS)

    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)

  18. A New Measurement Method of Iimage Encryption

    Energy Technology Data Exchange (ETDEWEB)

    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); Li, S [College of Measurement-Control Tech and Communications Engineering, Harbin University of Science and Technology, Harbin, 150080 (China); Zhang, X D [College of Measurement-Control Tech and Communications Engineering, Harbin University of Science and Technology, Harbin, 150080 (China)

    2006-10-15

    Image scrambling transformation is applied widely in the digital watermarking and image encryption. Although more and more scrambling algorithms appear, they lack a method to evaluate the image scrambling degree. According to the relative differences of a point and adjacent point in scrambling front and back, a new method which judges the scrambling degree is proposed. Not only it can evaluate the change of each pixel's position, but also evaluate the change of adjacent pixel's value. Apply Matlab to the simulation experiment, the result indicated that this method can evaluate image scrambling degree well, and it accorded with people's vision too.

  19. An image processing algorithm for PPCR imaging

    Science.gov (United States)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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。

  1. SRI RAMSHALAKA: A VEDIC METHOD OF TEXT ENCRYPTION AND DECRYPTION

    Directory of Open Access Journals (Sweden)

    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.

  2. Image reconstruction algorithms from projections

    International Nuclear Information System (INIS)

    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

  3. Image feature extraction in encrypted domain with privacy-preserving SIFT.

    Science.gov (United States)

    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

  4. 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

    Institute of Scientific and Technical Information of China (English)

    沈学举; 刘旭敏; 许芹祖; 林超

    2014-01-01

    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。%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 .

  5. Spaceborne SAR Imaging Algorithm for Coherence Optimized.

    Directory of Open Access Journals (Sweden)

    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.

  6. Spaceborne SAR Imaging Algorithm for Coherence Optimized.

    Science.gov (United States)

    Qiu, Zhiwei; Yue, Jianping; Wang, Xueqin; Yue, Shun

    2016-01-01

    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. PMID:26871446

  7. Spaceborne SAR Imaging Algorithm for Coherence Optimized

    Science.gov (United States)

    Qiu, Zhiwei; Yue, Jianping; Wang, Xueqin; Yue, Shun

    2016-01-01

    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. PMID:26871446

  8. Improved decryption quality and security of a joint transform correlator-based encryption system

    Science.gov (United States)

    Vilardy, Juan M.; Millán, María S.; Pérez-Cabré, Elisabet

    2013-02-01

    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.

  9. Private predictive analysis on encrypted medical data.

    Science.gov (United States)

    Bos, Joppe W; Lauter, Kristin; Naehrig, Michael

    2014-08-01

    Increasingly, confidential medical records are being stored in data centers hosted by hospitals or large companies. As sophisticated algorithms for predictive analysis on medical data continue to be developed, it is likely that, in the future, more and more computation will be done on private patient data. While encryption provides a tool for assuring the privacy of medical information, it limits the functionality for operating on such data. Conventional encryption methods used today provide only very restricted possibilities or none at all to operate on encrypted data without decrypting it first. Homomorphic encryption provides a tool for handling such computations on encrypted data, without decrypting the data, and without even needing the decryption key. In this paper, we discuss possible application scenarios for homomorphic encryption in order to ensure privacy of sensitive medical data. We describe how to privately conduct predictive analysis tasks on encrypted data using homomorphic encryption. As a proof of concept, we present a working implementation of a prediction service running in the cloud (hosted on Microsoft's Windows Azure), which takes as input private encrypted health data, and returns the probability for suffering cardiovascular disease in encrypted form. Since the cloud service uses homomorphic encryption, it makes this prediction while handling only encrypted data, learning nothing about the submitted confidential medical data.

  10. RC4 Stream Encryption Algorithm Based on Chaos%基于混沌的 RC4 流加密算法

    Institute of Scientific and Technical Information of China (English)

    刘宴兵; 田四梅; 唐浩坤; 吕淑品

    2011-01-01

    针对 WEP、TKIP 使用 IV 向量存在的安全隐患问题,提出一种将混沌映射与 RC4 算法相结合的加密算法,并给出相应的密钥管理方案,同时对该加密算法的密钥空间、随机性及加密效果进行分析.基于混沌的 RC4 算法利用混沌随机序列作为种子密钥,提高密钥的随机性,增加破译难度,且密钥变换空间相比 WEP、TKIP 得到较大的拓展.%Aiming at the problem that vector Ⅳ of WEP and TKIP exists security risks, an encryption algorithm based on chaos and RC4 algorithm is proposed, corresponding key management is followed, while making analysis of the key space, randomicity and encryption effect.The algorithm based on chaos and RC4 algorithm uses chaos random sequence as seed key to improve the randomness of seed key, increases the difficult of deciphering, and compared with WEP and TKIP the space of key transformation is expanded.

  11. E-mail System Based on DES and RSA Encryption Algorithm%基于DES和RSA加密的邮件系统

    Institute of Scientific and Technical Information of China (English)

    蔡斌

    2013-01-01

    随着网络技术的发展,电子邮件的使用越来越多,其安全性也得到越来越多的关注.论文设计的安全电子邮件系统是以对电子邮件内容加以保护的方式,即采用DES加密算法,保证邮件内容在被发送到互联网上之前被加密成为密文,并将公开密钥技术RSA用在电子邮件系统中加密DES密钥,从而有效地实现了电子邮件内容的安全性和保密性以及密钥分配问题.%With the development of network technology,the email accepts more and more usage and the email security receives more and more people's value.This article designs the security electronic mail system by performs the way to protect the email content,namely uses the DES encryption algorithm,guaranteed the mail content is encrypted before transmitted to the Internet,and uses public key technology RSA in the electronic mail system encrypts the DES key,thus effectively realized the email content security as well as the key assignment problem.

  12. FPGA Implementation of Secure Force (64-Bit Low Complexity Encryption Algorithm

    Directory of Open Access Journals (Sweden)

    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.

  13. The Mainstream Image Encryption Technology and Its New Progress%主流图像加密技术及其新进展

    Institute of Scientific and Technical Information of China (English)

    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.

  14. 一种基于双重加密的DWT-DCT域音频公开水印算法%An Audio Public Watermarking Algorithm Based on Double Encrypting in DWT-DCT Domain

    Institute of Scientific and Technical Information of China (English)

    杨志疆; 赵红

    2012-01-01

    In this paper, a new public audio watermarking algorithm based on DWT and DCT is proposed. The scheme proposes to use image scrambling and chaos encrypting as preprocessing during watermark embedding. It makes full use of the multi-resolution of DWT and the energy concentrated of DCT and enbeds encrypted watermark by quantification process in DC and several low frequency AC coefficients of the audio signal. Experimental results show that the proposed scheme has good performance of computing efficiency, security, imperceptibili-ty,highly good robustness to common audio processing operation.%提出了一种新的基于DWT和DCT音频公开水印算法.算法应用图像置乱与混沌原理对水印图像进行双重加密,并充分利用DWT的多分辨率特性与DCT的聚能特性对选取的多段音频进行处理,然后再把加密后的水印嵌入到各段的DCT低中频系数的量化中.仿真实验表明,该算法高效、安全性能好,且具有较好的不可感知性,对常见的音频处理具有较好的鲁棒性.

  15. SOFTWARE IMPLEMENTATION OF AN ECC ENCRYPTION ALGORITHM OVER PRIME FIELDS%素数域上ECC加密算法的软件实现

    Institute of Scientific and Technical Information of China (English)

    刘磊

    2012-01-01

    椭圆曲线密码是目前公认的每比特安全性最高的密码体制,它具有安全性高、速度快、密钥短、实现时所需占用资源少等优点,非常适合应用于银行结算、电子商务和通信等领域,因此研究椭圆曲线密码的实现有重要意义.首先讨论椭圆曲线密码基本理论,然后介绍安全椭圆曲线选取方法以及经典的ECC加密算法,最后在Core(TM)2 Duo CPU E7500 2.93GHz实验平台上用标准C语言对该算法进行实现,验证该加密算法的可行性.%The elliptic curve cryptography (ECC) is generally recognised at present as the most secure encryption system, which provides highest level of security strength-per-bit and has many advantages such as higher safety property, faster speed, shorter key lengths and fewer computational resources for implementation, and is very suitable for the sectors of bank settlement, e-commerce and communication. Therefore it is of significance to study the software implementation of ECC encryption algorithm. In this paper, we first introduce the basic theory of elliptic curve cryptography, and then describe the way to select a secure elliptic curve and the classic ECC encryption algorithm. Finally, we implement this algorithm in C and the assembler on a Core(TM)2 Duo CPU E75OO 2.93GHz workstation, and testify the feasibility of it.

  16. 基于伪随机序列的Arnold加密算法%Arnold Encryption Algorithm Based on PN Sequence

    Institute of Scientific and Technical Information of China (English)

    徐光宪; 吴巍

    2012-01-01

    Arnold Cat transformation is a classical algorithm of image scrambling. But its periodicity restrains the times of image scrambling,so the number of the keys is not enough. This paper presented a modified Arnold method, which u-ses PN sequence and secure hash algorithm to generate a random parameter sequence, then divides an image into 4 pieces and carries out Arnold algorithm to the 4 pieces respectively. The Arnold algorithm effectively increases the number of the keys,and overcomes the attack via the exhaustive analysis, which enhances the security.%Arnold变换是一种经典的图像置乱算法.由于其具有周期性,导致密钥量不够.提出了一种改进的Arnold变换方法,即引入伪随机序列并利用安全哈希算法产生随机参数序列,将数字图像分块,并对每个块图像分别进行Arnold变换,最终得到一幅置乱图像.该算法有效地增加了密钥量,可以克服通过穷举分析等手段进行的攻击,增加了图像的安全性.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. STEGANOGRAPHY FOR TWO AND THREE LSBs USING EXTENDED SUBSTITUTION ALGORITHM

    Directory of Open Access Journals (Sweden)

    R.S. Gutte

    2013-03-01

    Full Text Available The Security of data on internet has become a prior thing. Though any message is encrypted using a stronger cryptography algorithm, it cannot avoid the suspicion of intruder. This paper proposes an approach in such way that, data is encrypted using Extended Substitution Algorithm and then this cipher text is concealed at two or three LSB positions of the carrier image. This algorithm covers almost all type of symbols and alphabets. The encrypted text is concealed variably into the LSBs. Therefore, it is a stronger approach. The visible characteristics of the carrier image before and after concealment remained almost the same. The algorithm has been implemented using Matlab.

  19. Optical image encryption using equal modulus decomposition and multiple diffractive imaging

    Science.gov (United States)

    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.

  20. 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

    Institute of Scientific and Technical Information of China (English)

    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。

  1. Recent advances in optical encryption techniques

    OpenAIRE

    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.

  2. 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

    Institute of Scientific and Technical Information of China (English)

    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。

  3. CHAOS-BASED ADVANCED ENCRYPTION STANDARD

    KAUST Repository

    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

  4. IMPROVED ALGORITHM FOR STRIPMAP SAR IMAGING

    Institute of Scientific and Technical Information of China (English)

    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.

  5. Comparative Study of Image Denoising Algorithms in Digital Image Processing

    Directory of Open Access Journals (Sweden)

    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.

  6. Decryption of pure-position permutation algorithms

    Institute of Scientific and Technical Information of China (English)

    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.

  7. A Hybrid Approach for Detecting Stego Content in Corporate Mail Using Neural Network Based Simplified-Data Encryption Standard Algorithm

    Directory of Open Access Journals (Sweden)

    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.

  8. Optical encryption with cascaded fractional wavelet transforms

    Institute of Scientific and Technical Information of China (English)

    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.

  9. Volumetric Light-field Encryption at the Microscopic Scale

    CERN Document Server

    Li, Haoyu; Muniraj, Inbarasan; Schroeder, Bryce C; Sheridan, John T; Jia, Shu

    2016-01-01

    We report a light-field based method that allows the optical encryption of three-dimensional (3D) volumetric information at the microscopic scale in a single 2D light-field image. The system consists of a microlens array and an array of random phase/amplitude masks. The method utilizes a wave optics model to account for the dominant diffraction effect at this new scale, and the system point-spread function (PSF) serves as the key for encryption and decryption. We successfully developed and demonstrated a deconvolution algorithm to retrieve spatially multiplexed discrete and continuous volumetric data from 2D light-field images. Showing that the method is practical for data transmission and storage, we obtained a faithful reconstruction of the 3D volumetric information from a digital copy of the encrypted light-field image. The method represents a new level of optical encryption, paving the way for broad industrial and biomedical applications in processing and securing 3D data at the microscopic scale.

  10. High Lightweight Encryption Standard (HLES as an Improvement of 512-Bit AES for Secure Multimedia

    Directory of Open Access Journals (Sweden)

    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.

  11. Comparative Study of Image Denoising Algorithms in Digital Image Processing

    OpenAIRE

    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...

  12. Comparative Study of Image Denoising Algorithms in Digital Image Processing

    OpenAIRE

    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...

  13. A RANDOMIZED SELECTIVE ENCRYPTION USING HASHING TECHNIQUE FOR SECURING VIDEO STREAMS

    Directory of Open Access Journals (Sweden)

    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.

  14. TinySBSec-the new lightweight WSN link-layer encryption algorithm%TinySBSec-新型轻量级WSN链路层加密算法

    Institute of Scientific and Technical Information of China (English)

    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。

  15. A cubic map chaos criterion theorem with applications in generalized synchronization based pseudorandom number generator and image encryption

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. A novel method of space-domain image encryption%一种数字图像空域加密新算法

    Institute of Scientific and Technical Information of China (English)

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

    OpenAIRE

    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...

  18. AN EFFICIENT BTC IMAGE COMPRESSION ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Block truncation coding (BTC) is a simple and fast image compression technique suitable for realtime image transmission, and it has high channel error resisting capability and good reconstructed image quality. The main shortcoming of the original BTC algorithm is the high bit rate (normally 2 bits/pixel). In order to reduce the bit rate, an efficient BTC image compression algorithm was presented in this paper. In the proposed algorithm, a simple look-up-table method is presented for coding the higher mean and the lower mean of a block without any extra distortion, and a prediction technique is introduced to reduce the number of bits used to code the bit plane with some extra distortion. The test results prove the effectiveness of the proposed algorithm.

  19. Encrypted integer division

    NARCIS (Netherlands)

    Veugen, P.J.M.

    2010-01-01

    When processing signals in the encrypted domain, homomorphic encryption can be used to enable linear operations on encrypted data. Integer division of encrypted data however requires an additional protocol with the server and will be relatively expensive. We present new solutions for dividing encryp

  20. Image Series Segmentation and Improved MC Algorithm

    Institute of Scientific and Technical Information of China (English)

    WAN Wei-bing; SHI Peng-fei

    2008-01-01

    A semiautomatic segmentation method based on active contour is proposed for computed tomog-raphy (CT) image series. First, to get initial contour, one image slice was segmented exactly by C-V method based on Mumford-Shah model. Next, the computer will segment the nearby slice automatically using the snake model one by one. During segmenting of image slices, former slice boundary, as next slice initial con-tour, may cross over next slice real boundary and never return to right position. To avoid contour skipping over, the distance variance between two slices is evaluated by an threshold, which decides whether to initiate again. Moreover, a new improved marching cubes (MC) algorithm based on 2D images series segmentation boundary is given for 3D image reconstruction. Compared with the standard method, the proposed algorithm reduces detecting time and needs less storing memory. The effectiveness and capabilities of the algorithm were illustrated by experimental results.

  1. Least significant qubit algorithm for quantum images

    Science.gov (United States)

    Sang, Jianzhi; Wang, Shen; Li, Qiong

    2016-08-01

    To study the feasibility of the classical image least significant bit (LSB) information hiding algorithm on quantum computer, a least significant qubit (LSQb) information hiding algorithm of quantum image is proposed. In this paper, we focus on a novel quantum representation for color digital images (NCQI). Firstly, by designing the three qubits comparator and unitary operators, the reasonability and feasibility of LSQb based on NCQI are presented. Then, the concrete LSQb information hiding algorithm is proposed, which can realize the aim of embedding the secret qubits into the least significant qubits of RGB channels of quantum cover image. Quantum circuit of the LSQb information hiding algorithm is also illustrated. Furthermore, the secrets extracting algorithm and circuit are illustrated through utilizing control-swap gates. The two merits of our algorithm are: (1) it is absolutely blind and (2) when extracting secret binary qubits, it does not need any quantum measurement operation or any other help from classical computer. Finally, simulation and comparative analysis show the performance of our algorithm.

  2. 基于MD5加密的Tornado码复制算法改进%An improved algorithm based on MD5 encryption Tornado code

    Institute of Scientific and Technical Information of China (English)

    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。

  3. An improved algorithm based on MD5 encryption Tornado code%基于MD5加密的Tornado码复制算法改进

    Institute of Scientific and Technical Information of China (English)

    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.

  4. Modified Projective Synchronization between Different Fractional-Order Systems Based on Open-Plus-Closed-Loop Control and Its Application in Image Encryption

    Directory of Open Access Journals (Sweden)

    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.

  5. 基于Arnold变换及混沌加密的遥感影像机密信息隐藏研究%Study on Hidden Confidential Information of Remote Sensing Images Based on Arnold Transformation and Chaotic Encryption

    Institute of Scientific and Technical Information of China (English)

    段晓颖; 王阿川

    2011-01-01

    目前数字水印技术已经相当成熟,但是鲜见关于遥感影像机密信息隐藏技术的报道。遥感影像中有些机密信息对没有权限的用户是不可见的,因此我们需要使用信息隐藏技术将其中的机密信息隐藏起来。本文提出了一种基于Arnold变换及混沌加密的机密信息隐藏算法,该算法首先使用Amold变换和混沌加密技术对机密信息进行加密处理,然后采用基于DWT变换的信息隐藏算法将机密信息隐藏到伪遥感影像中。实验结果表明本算法对遥感影像机密信息可进行有效的隐藏,保护了机密信息的安全,由此可以看出信息隐藏技术在遥感影像机密信息安全方面有很重要的作用。%Currently, digital watermarking technology is quite mature, but the reports on the confidential information hiding technology of remote sensing images are rare. Some confidential information of remote sensing images is invisible to the users without permission, so therefore, we need to use information hiding technology to hide confidential information. A hiding algorithm of confidential information based on Arnold transformation and chaotic eneryption technology is presented The algorithm first uses Arnold transformation and chaotic encryption technology to encrypt confidential information and then uses the information hiding algorithm based on DWT transformation to hide the confidential information in the pseudo - remote sensing images. The experimental results show that the confidential information of remote sensing images can be effectively hidden by the algorithm which protects the security of the confidential information, so hiding confidential information in remote sensing images plays an important role in information security.

  6. Fractional Fourier domain optical image hiding using phase retrieval algorithm based on iterative nonlinear double random phase encoding.

    Science.gov (United States)

    Wang, Xiaogang; Chen, Wen; Chen, Xudong

    2014-09-22

    We present a novel image hiding method based on phase retrieval algorithm under the framework of nonlinear double random phase encoding in fractional Fourier domain. Two phase-only masks (POMs) are efficiently determined by using the phase retrieval algorithm, in which two cascaded phase-truncated fractional Fourier transforms (FrFTs) are involved. No undesired information disclosure, post-processing of the POMs or digital inverse computation appears in our proposed method. In order to achieve the reduction in key transmission, a modified image hiding method based on the modified phase retrieval algorithm and logistic map is further proposed in this paper, in which the fractional orders and the parameters with respect to the logistic map are regarded as encryption keys. Numerical results have demonstrated the feasibility and effectiveness of the proposed algorithms.

  7. Algorithms for image processing and computer vision

    CERN Document Server

    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

  8. An Ensemble Classification Algorithm for Hyperspectral Images

    Directory of Open Access Journals (Sweden)

    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.

  9. 基于CUDA的高效IDEA加密算法设计与实现%Design and Implementation of Efficient IDEA Encryption Algorithm Based on CUDA

    Institute of Scientific and Technical Information of China (English)

    朱兴锋

    2011-01-01

    为了实现一个高效的加密算法,本文充分利用图形处理器(GPU)的并行处理能力,提出基于CUDA实现IDEA加密算法的方法,对该方法的设计和实现进行详细的阐述,并通过实验与传统的基于CPU的实现方法进行性能比较,基于CUDA的IDEA实现速度上远远高于基于CPU的实现.%With the parallel processing capability of Graphics Processing Unit (GPU) , design and implementation of IDEA algo-rithm is proposed as an efficient encryption and decryption algorithm, which is elaborated in this paper. Both traditional CPU-based and new one based on GPU are implemented. At last, the performance based on GPU is analyzed, which runs much faster than the traditional approach.

  10. Fast SAR Imaging Algorithm for FLGPR

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A fast SAR imaging algorithm for near- field subsurface forward-looking ground penetrating radar (FLGPR) is presented. By using nonstationary convolution filter, the refocused image spectrum can be reconstructed directly from the backscattered signal spectrum of target area. The experimental results show the proposed method can fast achieve image refocusing. Also it has higher computational efficiency than the phase-shift migration approach and the delay-and-sum (DAS) approach.

  11. 一种基于混沌加密的 DWT 数字音频水印算法%A Digital Audio Watermarking Algorithm Based on Chaotic Encrypting in DWT

    Institute of Scientific and Technical Information of China (English)

    陈雪松; 李昊天; 贾瑞成; 孙立娜; 卜广龙

    2014-01-01

    An algorithm based on the chaos theory of digital audio watermarking algorithm is proposed .For the security of digital audio watermark, the chaos theory in the high dimensional chaos theory is applied to the watermark encryption .For the first time, we use chaotic sequence to encrypt watermark signal , and the second time , we use high dimension chaotic system to encrypt the encrypted watermark again .In order to improve the robustness of the algorithm , the algorithm was embed the same watermark in-formation repeatedly by the way .The principle of majority was used to enhance the error correction capability of watermark infor -mation when the watermark information was extracted .Simulation results showed that the algorithm is of better robustness and se-curity.%提出一种基于混沌加密的DWT数字音频水印算法。算法从水印的安全性出发,水印信息加密过程引入混沌理论,第一次加密过程利用二维映射对水印信息进行置乱加密,再利用高维混沌系统对得到的第一次加密后的水印进行二次加密。为了提高算法鲁棒性,采用同时嵌入多个同一水印信息的方式,通过少数服从多数的原则来确定提取出的水印信息,进而增强水印信息的纠错能力,提高水印的鲁棒性。仿真实验结果及数据分析表明该算法具有较好的鲁棒性及安全性。

  12. Image Recovery Algorithm Based on Learned Dictionary

    Directory of Open Access Journals (Sweden)

    Xinghui Zhu

    2014-01-01

    Full Text Available We proposed a recovery scheme for image deblurring. The scheme is under the framework of sparse representation and it has three main contributions. Firstly, considering the sparse property of natural image, the nonlocal overcompleted dictionaries are learned for image patches in our scheme. And, then, we coded the patches in each nonlocal clustering with the corresponding learned dictionary to recover the whole latent image. In addition, for some practical applications, we also proposed a method to evaluate the blur kernel to make the algorithm usable in blind image recovery. The experimental results demonstrated that the proposed scheme is competitive with some current state-of-the-art methods.

  13. RSA加密算法的有效实现及在云计算中的应用%Analysis to Effective Realization of RSA Encryption Algorithm and Its Application in the Cloud Computing

    Institute of Scientific and Technical Information of China (English)

    谢会娟; 韩昌豪; 吴明珠

    2014-01-01

    随着互联网的发展,云计算模式能够提供便捷的、可用的和按需要网络资源,云计算的核心是如何存储和管理用户的数据,除了配置存储设备的之外,还要考虑到存储在云中的数据的安全性。RSA加密算法是基于一个比较简单的数论-两个大素数相乘十分容易实现,但要对它的乘积进行因式分解却十分困难,RSA加密算法是将乘积公开作为加密密钥的非对称加密方法,在云计算中应用RSA算法对存储在云中的数据进行加密,能够保证了数据的安全性。%With the development of the Internet, cloud computing can provide convenient and available network resources, the core of cloud computing is how to store and manage user data, cloud computing does not provide storage devices, but also takes into account the security of the data stored in the cloud. RSA encryption algorithm is based on a relatively simple theory of math-multiplying two large prime numbers is very easy to achieve, but it's the factorization is very difficult, RSA encryption al⁃gorithm considers a product as a public encryption key and is an asymmetric encryption method. To ensure the security of the da⁃ta, RSA encryption algorithm is applied for the data storage in the cloud.

  14. Universal lossless compression algorithm for textual images

    Science.gov (United States)

    al Zahir, Saif

    2012-03-01

    In recent years, an unparalleled volume of textual information has been transported over the Internet via email, chatting, blogging, tweeting, digital libraries, and information retrieval systems. As the volume of text data has now exceeded 40% of the total volume of traffic on the Internet, compressing textual data becomes imperative. Many sophisticated algorithms were introduced and employed for this purpose including Huffman encoding, arithmetic encoding, the Ziv-Lempel family, Dynamic Markov Compression, and Burrow-Wheeler Transform. My research presents novel universal algorithm for compressing textual images. The algorithm comprises two parts: 1. a universal fixed-to-variable codebook; and 2. our row and column elimination coding scheme. Simulation results on a large number of Arabic, Persian, and Hebrew textual images show that this algorithm has a compression ratio of nearly 87%, which exceeds published results including JBIG2.

  15. Encryption And Portable Data Storage

    Directory of Open Access Journals (Sweden)

    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

  16. A Self-synchronizing Stream Encryption Scheme Based on One-Dimensional Coupled Map Lattices

    Institute of Scientific and Technical Information of China (English)

    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.

  17. 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

    Institute of Scientific and Technical Information of China (English)

    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.

  18. Optical image encryption based on gyrator transformation and chaotic function%基于回转器变换和混沌的光图像加密

    Institute of Scientific and Technical Information of China (English)

    孔德彭; 杜学文; 孔德辉

    2012-01-01

    提出一种基于混沌理论和回转器的光图像加密技术,它由混沌函数产生的随机相位掩膜对光学系统进行加密和解密.利用三种混沌函数对比研究,它们分别是改进的Logistic映射、Hybrid映射和Baker映射,给出了基于混沌理论与光学系统研究思路和方法,通过盲加密、旋转角度的盲解密来证实其鲁棒性与可靠性,借助计算机进行了模拟,证实了光学加密和解密实施可行性,最后给出了均方差的有效性.%The paper proposed a novel method of optical image encryption based on gyrator transformation and chaos theory. The random phase masks generated by chaotic function is used to encrypt and decrypt the optical system. In this method, the three kinds of chaotic functions are compared and studied. They can improve the Logistic mapping, Hybrid mapping and Baker mapping respectively. It gives research idea and method based on chaos theory and optical system. Its robustness and reliability is proved by blind encryption and the blind decryption of the rotation angle. Through the simulation on computer, the feasibility of the optical encryption and decryption is proved and the validity of the mean square error is given finally.

  19. Image Mosaicing Algorithm for Rolled Fingerprint Construction

    Institute of Scientific and Technical Information of China (English)

    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.

  20. Algorithm for Fast Registration of Radar Images

    Directory of Open Access Journals (Sweden)

    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.