Color Image Encryption Method Research Articles

Scale Invariant Digital Color Image Encryption Using a 3D Modular Chaotic Map

Cryptography is one of the most important security mechanisms for the transmission of digital media on the Internet. Most proposed cryptographic image methods based on chaotic maps are dependent upon image sizes and most of them worked on square images. In this paper for tackling this problem, a scale-invariant color image encryption method in three-dimensional space is presented. At first, the two-dimensional color image is converted into three-dimensional space, in this case, the red, green, and blue color spectrums are divided into a set of gray-level square sub-images. Then, to have confusion and diffusion properties, the 3D substitution and 3D permutation operation are performed on the sub-images. In substitution operations, the pixel values of the sub-images are changed with the help of XOR and circular shift operators with appropriate keys. In permutation operation, the position of the pixels is changed using modular three-dimensional chaos mappings. To have scale-invariant three-dimensional permutation, the sub-images are divided into one or more windows with equal size, and then 3D modular chaotic map operations are performed on each window with separate keys. Depending on the number of sub-images, there may be two last windows that have overlapping. To increase the speed of color image encryption, the steps of a 3D modular chaotic map on the windows can be implemented in parallel. The proposed approach relative to the similar color image encryption algorithms increases the key space and improves standard parameters, such as entropy, sensitivity, adjacent pixel correlations, and histogram uniformity.

A Digital Image Confidentiality Scheme Based on Pseudo-Quantum Chaos and Lucas Sequence.

Several secure image encryption systems have been researched and formed by chaotic mechanisms in current decades. This work recommends an innovative quantum color image encryption method focused on the Lucas series-based substitution box to enhance the competence of encryption. The suggested encryption technique has more excellent key space and significant confidentiality. The chaotic system, along with the substitution box, exhibits additional complicated dynamical behavior, sufficient arbitrariness, and uncertainty than all others focused on just chaotic models. Theoretical and simulation assessments show that the offered image encryption performs admirably, its traditional equivalents in terms by efficiency in terms of statistical analysis.

Optical color image encryption based on Hadamard single-pixel imaging and Arnold transformation

An optical color image encryption method based on Hadamard single-pixel imaging (SPI) and Arnold transformation is proposed, in which, optical full-color image encryption with good imaging quality and high security performance can be accomplished by only one bucket detector (BD). In the encryption process, after controlling and modulating the Hadamard matrix by the coefficient matrix key, three different sets of colored Hadamard patterns are generated to be projected onto the target colored object; Subsequently, the collected experimental data: R, G, and B components are detected by a BD, which are then scrambled by Arnold transformation to further increase the security; Finally the colored ciphertext image can be recombined and obtained to transferring to the receivers. During the decryption, with the colored ciphertext and all the corrected keys, the original secret color image can be successfully decrypted by the extraction of R, G, B components, inverse Arnold transformation, the correlated computation in SPI, and inverse Hadamard transformation. The feasibility of this method and its robustness against some types of attacks are verified by both computer simulations and optical experiments.

12×12 S-box Design and its Application to RGB Image Encryption

Customarily, 8×8 S-box is a 16×16 look up table over Galois field GF28, algebra over the binary field F2. A 12×12 S-box over GF212 is not workable as the computer memory does not manage it. The finite chain ring F2[x]<x12> is fundamentally an algebra over the binary field F2. In this paper we considered the advantage and devise a novel method of 12×12 S-box design over the unit elements of finite chain ring F2[x]<x12>. The newly obtained S-box has greatly higher confusion ability than any of 8×8 S-box. To observe this effect, an RGB image encryption application is given. In the proposed encryption scheme, we doubled the bits of 12×12 S-box from 12 to 24 for creating confusion in the data. Consequently, a new method of color image encryption is designed by which 24 binary bits are utilized at the place of byte. Whereas for diffusion we apply the linear permutation P=i×32 mod 257 and finally bitwise Exclusive-or operation is operationalized. Analysis reveals that the proposed image encryption approach might switch many 8×8 S-box based color image encryption schemes.

A color image encryption method based on memristive hyperchaotic system and DNA encryption

In this paper, a color image encryption method using the memristive hyperchaotic system and deoxyribonucleic acid (DNA) encryption is proposed. First, the pseudo-random sequences are generated by a keystream generation mechanism based on a memristive hyperchaotic system and the plain image. Due to this, the memristive hyperchaotic system has a complex dynamical behavior and is highly sensitive to initial conditions, the proposed keystream generation mechanism is highly random which is also dependent on the plain images. Second, a permutation based on the cycle-shift operation is designed to eliminate the correlations between adjacent pixels in the plain images. Then, the scrambled sequences are processed by DNA encryption to increase the system ability to defense the brute force attacks. Finally, the cipher image is obtained after the diffusion and interaction among red, green and blue components. Experimental analysis and performance comparisons show that the proposed method has high security, good efficiency and strong robustness under different attacks.

Color Image Encryption Using Pixel Scrambling Operator and Reality-Preserving MPFRHT

To ensure the confidentiality of color images during their storage or transmission on insecure networks, a number of encryption methods based on fractional transforms have been proposed and widely investigated. However, most of their outputs are complex values that are inconvenient for record and transmission. Also, those methods always deal with a whole color component with the same fractional-order and ignore the textural features that are contained in different image parts. In this paper, we first define a reality-preserving multiple-parameter fractional Hartley transform (RPMPFRHT), whose output is real value, and then a novel color image encryption method is proposed that divides the RGB components into different blocks and uses a constructed pixel scrambling operator to mix and hide the original color information. The outputs are transformed to different RPMPFRHT domains and further scrambled by a non-adjacent coupled map lattices system. Numerical simulations are performed to demonstrate that the proposed encryption algorithm is feasible, secure, sensitive to keys, and robust to potential attacks.

A fast color image encryption technique based on three dimensional chaotic map

In this paper, a fast color image encryption method based on the suggested three dimensional chaotic map is presented. Generally, the suggested map generates three numbers and then these numbers are Bitxor-ed with RGB channels of image. Process is continued with dividing an image into 4 × 4 parts and changing these parts locations. Proposed technique divides each part into 16 × 16 blocks and then the blocks are permuted with different keys of presented map. The encrypted image is generated after all blocks of parts permuted. This process guarantees the sensitivity of proposed approach in changing one bit of image and refers to the diffusion. Furthermore, proposed scheme saves the latest generated numbers of permuting process and uses them to permute next block. This process is very sensitive to any changes in keys and refers to the confusion. The evaluation results of standard tests on some images confirm that the proposed method has good key space, security, fast speed and strong robustness against most well-known attacks.

An Efficient and Highly Secure Technique to Encrypt and Decrypt Color Images

Digital color images are considered as the most widely used data. They are exchanged frequently on the internet and via email, so an efficient and highly secure method of color image encryption and decryption is needed. Different methods of encryption-decryption are used, but most of them suffer from low efficiency or low-security level or both. In this paper, an efficient and highly secure method of encryption-decryption will be proposed, tested, and implemented. The efficiency parameters will be calculated and compared with other methods’ parameters to prove the efficiency of the proposed method.

Color image encryption method based on 2D-variational mode decomposition

In order to reduce the correlation between adjacent pixels in a plaintext image, and to solve the small key space problem of image encryption algorithms when a low-dimension chaotic map is used, a new encryption method for color images is proposed based on two-dimensional variational mode decomposition (2D-VMD) combined with eight-dimensional (8D) hyper-chaotic systems. 2D-VMD decomposes R, G and B components of a color image respectively. The 8D hyper-chaotic system is constructed by means of variable coupling. After improving and combining the original sequences obtained by iterating the system, two groups of key sequences associated with the plain-image are obtained. One group is used to scramble each mode image obtained by 2D-VMD; the other is used to replace the pixel values of the scrambled mode images. For different mode images, different key sequences are adopted. The encrypted images whose number is equal to the number of the modes can then be obtained. The experimental results show that, compared with the existing methods, the correlation coefficients between the pixels in the spatial domain of the plain-image can be reduced by 2D-VMD, as it’s more difficult to crack. In addition, the encryption method has better statistical and differential characteristics, as well as large enough key space, and better plain-image sensitivity.

Color image encryption method based on computer generated hologram and &lt;i&gt;θ&lt;/i&gt; modulation

In this paper, a new method of encrypting a color image based on &lt;i&gt;θ&lt;/i&gt; modulation is proposed by using the tricolor principle and computer-generated hologram (CGH) technology. The encryption process includes the &lt;i&gt;θ&lt;/i&gt;-modulated three primary color components and the coding of computer-generated hologram, which is implemented in a Fresnel diffraction and spatial filtering system. Firstly, the color image modulated by the first random phase key is divided into three encryption channels by red laser, green laser, blue laser, and tricolor filters. Each channel is introduced by a transmissive amplitude-type sinusoidal grating with different directions, which is used to separate the three primary color components in the spatial spectrum plane. Secondly, the modulation results of tricolor components are superimposed together to form a compound image, and the phase truncation of the superposition result is performed to achieve the asymmetric encryption. Finally, the amplitude of the compound image is modulated by the second random phase key and is encoded into a binary real-value gray-color CGH by Roman-type coding method. Therefore, the gray-color information of the original image is completely hidden in the encrypted CGH, which is more general and deceptive in the storage and transmission process. Decryption is an inverse process of the encryption. Firstly, the encrypted CGH is placed on the input plane of the spatial filtering and Fresnel diffraction system. Secondly, the demodulation of CGH phase key and the spatial filtering based on optical filter are performed. Finally, the color plaintext image is obtained by using the correct Fresnel diffraction. The simulation results show the validity and feasibility of the proposed method. In addition, the anti-noise attack and anti-shearing attack performance of this color image encryption method are investigated. Compared with results from the three presented methods reported in the literature, our investigated results demonstrate that this method has good robustness to noise attack and shearing attack, and has obvious advantages when the attack noise density is larger. Due to the characteristics of high security and anti-noise, we believe that this color image encryption method promises to have important applications in the information transmission and multi-user authentication.

A Novel Delay Linear Coupling Logistics Map Model for Color Image Encryption.

With the popularity of the Internet, the transmission of images has become more frequent. It is of great significance to study efficient and secure image encryption algorithms. Based on traditional Logistic maps and consideration of delay, we propose a new one-dimensional (1D) delay and linearly coupled Logistic chaotic map (DLCL) in this paper. Time delay is a common phenomenon in various complex systems in nature, and it will greatly change the dynamic characteristics of the system. The map is analyzed in terms of trajectory, Lyapunov exponent (LE) and Permutation entropy (PE). The results show that this map has wide chaotic range, better ergodicity and larger maximum LE in comparison with some existing chaotic maps. A new method of color image encryption is put forward based on DLCL. In proposed encryption algorithm, after various analysis, it has good encryption performance, and the key used for scrambling is related to the original image. It is illustrated by simulation results that the ciphered images have good pseudo randomness through our method. The proposed encryption algorithm has large key space and can effectively resist differential attack and chosen plaintext attack.

Image Encryption Using Columnar Transportation Technique and Bits Reversing

Security has become very important aspect during data transmission and storage. Cryptography is used to maintain security. Columnar Transportation Technique is one of the most common methods that used in image encryption. In this paper, we proposed an encryption technique based on columnar Transportation and bits reversing, and named the method (CTR). Different colored images are used in the experiments. Experimental results showed that the proposed method is a secure and effective as a color image encryption method.&#x0D;

Color image encryption in non-RGB color spaces

To protect the contents of images in the mobile internet era during image storage and transmission, image encryption has achieved a tremendous success during the last decades. Traditional color image encryption method often use the RGB color space. We have the observation that in non-RGB color spaces, the luminance channels often contain more information for content recognition than the chroma channels do. Thus, in this paper we propose to use high level encryption schemes in more informative channels and low level encryption schemes in less informative channels. The 2D Arnold’s cat map followed by the 3D Lu chaotic map are conducted in the luminance channel. The less complicated DNA coding and 1D logistic map based encryption scheme is leveraged in the chroma channels. We use this strategies in 4 typical non-RGB color spaces, i.e., YCbCr, YIQ, HSV, L*a*b*. We evaluate and compare the performances and the time consumptions of the methods in the 4 Non-RGB color spaces. The experimental results reveal that the encryption methods in Non-RGB color spaces can achieve similar results as the method that conducts the same encryption level in each channel of the RBG color space, including the resistance to several attacks such as brute-force attack, statistic attack, correlation attack, while consuming less time. The method in YCbCr color space performances the best in the time consumption.

Image encryption based on Arnold transformation

In this paper we present a new color image encryption method based on Arnold transformation and logistic chaotic map. The proposed approach uses the Arnold matrix modified and adapted to simultaneously make a permutation and confusion to image pixels using logistic map, then shifting pixel thus obtained will be put in. The result and analysis take shelter our cryptosystem against static attack and exhaustive.

A new image encryption using color scrambling based on chaotic permutation multiple circular shrinking and expanding

In this paper, we propose a new color image encryption method using color scrambling based on the chaotic permutation multiple circular shrinking and expanding (CPMCS/ CPMCE). The plain color image with a size of m x n x 3 is arranged in two-dimensional array, where each row consists of the Red, Green, and Blue (RGB) component, forming two-dimensional array with a size of m x 3n. The arranged 2D array then permuted by CPMCS for the each row and column. To reconstruct the original image, the ciphered image is arranged in 2D array then is permuted by CPMCE for each column and row. The proposed method is characterized by very high key space that reaches 22,895,713 for an image size of 256x256, so that resistance to brute force attack and can anticipate the emergence of quantum computers. It also resistant to a differential attack due to change a single bit in the plain image causes a significant change in the ciphered image. The proposed encryption also yield completely difference ciphered image series from the same plain image just using arbitrary increment sequence key. It is also robust to JPEG compression so the ciphered image can be stored in smaller size, such as for the ciphered Lena image only needs 1/5.2 of the original one when compressed using JPEG 70 %. It also resistant to noise scheme (Gaussian, Poisson, Salt&Pepper, and spekle), data loss, and brightness-contrast adjustment, so the ciphered image can be transmitted in a non error free communication system.

An asymmetric color image encryption method by using deduced gyrator transform

An encryption algorithm is proposed by using the properties of deduced gyrator transform (GT). After being transformed by the GT algorithm and multiplied by a phase distribution p*, the spectrum modulus of the input image is considered to be the encrypted image by further performing Fourier transformation. To resist the attack from iterative phase retrieval, the red, green and blue components of the input image is modulated by a random phase mask and then combined using convolution. The encryption result is real-valued, which is convenient for display, transmission and storage. In the decryption process, the three original color components can be recovered with decryption keys which are different from the encryption keys. An optoelectronic hybrid system for the encryption process is also presented. Computer simulations are presented to demonstrate its performance, and the security of the proposed system is analyzed as well.

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

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.

Color 3D Image Encryption Technique by Combined Use of Computational Integral Imaging Joint Image Scrambling Technique

In this paper, we propose a novel three-dimensional (3D) color image encryption scheme based on computational integral imaging (CII) and Arnold transform technique. An elemental image array (EIA) is firstly captured by recording the light rays emanating from 3D image through a lenslet array. Then, the captured color EIA is decomposed into three independent channels: red, green and blue, and each channel is encrypted by Arnold transform. In the reconstruction process, the pseudo-inverse filter is used to improve quality of the reconstructed 3D color image in CII system. Numerical simulations have been done to prove the validity and the security of the proposed 3D color image encryption method.

Optical color image encryption using position multiplexing technique based on phase truncation operation

Abstract We propose an optical color image cryptosystem based on position multiplexing technique and phase truncation operation. Compared with the reported color image encryption method, we employ the position multiplexing technique to encrypt the color image in only one spatial channel. Meanwhile, our proposed method can maintain the nonlinear characteristic of the cryptosystem and avoid various types of the currently existing attacks, especially the iterative attack. Simulation results are presented to demonstrate the security and robustness performance of the proposed method.

RGB Color Image Encryption Method Based on Lorenz Chaotic System and DNA Computation

In this paper, an RGB color image encryption method based on the Lorenz chaotic system and DNA computation is presented. This method can not only change the location of the image pixel but also change the pixel values. Firstly, we split the RGB color image into R, G, B three components. Then, we use the 2D-hyperchaotic sequence to disorder the location of R, G, B three-component pixels. Secondly, three different chaotic sequences are generated by a one-dimensional logistic chaotic map, and the pixel values of the three components R, G, B can be scrambled through the three logistic chaotic sequences. Then the R, G, B digital images can be transformed into DNA coding matrices based on DNA coding rules. Thirdly, 3D chaotic sequences are generated by use of Lorenz chaotic system and are encoded based on DNA encoding rules in order to generate three DNA sequences. Finally, the encrypted image can be obtained by utilizing DNA operations on the DNA sequences of three components R, G, B and DNA sequences generated by the Lorenz chaotic system. The experiment results and encryption effect demonstrate that the proposed scheme is effective, and it has strong sensibility, high security, and good ability of resisting statistic attack.