Double Random Phase Encoding Research Articles

Efficient Three-Dimensional Video Cybersecurity Framework Based on Double Random Phase Encoding

With the rapidly increasing rate of using online services and social media websites, cybercriminals have caused a great deterioration in the network security with enormous undesired consequences. Encryption techniques may be ... | Find, read and cite all the research you need on Tech Science Press

Three-Dimensional Photon Counting Optical Encryption With Enhanced Visual Quality and Security Level

In this paper, we propose three-dimensional (3D) photon counting double random phase encryption (DRPE) with enhanced visual quality and security level. Conventional 3D photon counting DRPE can quickly encrypt the data by using the 4f optical system and random phase masks with enhanced security because the 3D photon counting technique is used. 3D photon counting DRPE extracts photons from the encrypted data by using statistical methods such as the Poisson random process, and the visual quality of the decrypted data can be enhanced through the 3D reconstruction process. However, it still has a problem to visualize the data when we extract extremely a few photons. To improve the security and the visual quality of the decrypted data, we propose the random amplitude reconstruction process in the encryption stage. Our proposed method reconstructs the amplitude of the encrypted data at a random depth. Thus, the shifting pixel value and depth information can be another important key for decryption through the random process. Therefore, it can effectively decrypt data securely, and the visual quality of the decrypted data can be enhanced. Finally, through the random reconstruction process in the decryption stage, our proposed method can simultaneously enhance the security and visual quality. To verify our proposed method, we carry out the simulation and optical experiment.

Medical image encryption based on biometric keys and lower–upper decomposition with partial pivoting

The security of medical image transmission in telemedicine is very important to patients' privacy and health. A new asymmetric medical image encryption scheme is proposed. The medical image is encrypted by two spiral phase masks (SPM) and the lower-upper decomposition with partial pivoting, where the SPM is generated from the iris, chaotic random phase mask, and amplitude truncated spiral phase transformation. The proposed scheme has the following advantages: First, the iris is used for medical image encryption, which improves the security of the encryption scheme. Second, the combination of asymmetric optical encryption and three-dimensional Lorenz chaos improves the key space and solves the linear problem based on double-random phase encoding. Third, compared with other encryption schemes, the proposed scheme has advantages in occlusion attacks, key space, correlation, and information entropy. Numerical simulation and optical results verify the feasibility and robustness of the encryption scheme.

Exploiting optical chaos for double images encryption with compressive sensing and double random phase encoding

Images as a common information carrier are widely disseminated and used at present, meanwhile, image security and privacy protection are also facing severe tests. To enhance the security of images, an asymmetric double color images cryptosystem introduced optical chaos technology is proposed based on compression sensing (CS) and double random phase encoding (DRPE). It is the first time that the combination of CS, DRPE and optical chaos technology is demonstrated to the best of our knowledge. By means of the optical chaos keys generated by a constructed optical chaos model, the two color images are first decomposed into their respective Red–Green–Blue (RGB) channels, CS based on discrete wavelet transform is then performed for the first encryption. Afterwards, the second encrypion of DRPE in fractional Fourier transform domain (FrFT) with optical chaos technology is also used, and the asymmetric encryption by carrying out equal modulus decomposition (EMD) with optical chaos keys further enhance the security finally. Simulation results and security analysis confirm that the cryptosystem owns multi-layer protection and adequate resistance to brute-force attack, statistical attack, differential attack, noise attack and chosen-plaintext attack, which is efficient and capable of guaranteeing the security of images and can provide an alternative solution for image security and privacy protection.

Security analysis and modified attack algorithms for a nonlinear optical cryptosystem based on DRPE

In this paper, security of a nonlinear optical cryptosystem based on double random phase encoding (DRPE) is analyzed. In the cryptosystem, a time-varying nonlinear term is combined with the classical DRPE technique to enhance security. The advantages of the nonlinear term are its easy distribution and no effect on the decrypted image. Also, it is confirmed that the method is resistant to conventional plaintext attacks such as known-plaintext attack, chosen-plaintext attack, and ciphertext only attack. However, our security analysis shows that the method is vulnerable to the modified chosen-plaintext, and known-plaintext attacks. The original image can be recovered successfully using the proposed attack algorithms. Numerical simulation results are presented to validate the proposed attack methods and test effectiveness of our analysis.

A novel 1D chaotic system for image encryption, authentication and compression in cloud

To solve the privacy image problem stored in cloud, we propose a compressive sensing (CS) based image compression, authentication, encryption algorithm in cloud, which can implement computation outsourcing to get rid of the expensive storage and computation costs. To achieve these goals, combined with the logistic-tent-sine chaotic map, a logistic-tent-sine chaotic map (LTSS) is proposed for it has larger chaotic ranges and better chaotic behaviors than simple 1D chaotic map such as a logistic chaotic map. Then, the LTSS chaotic system is employed for image protection algorithm in cloud, which contains three parts: data owner, cloud services and data user. The primary role of the data owner part is to compress and encrypt the image while embedding the owner’s Palmprint discriminative and binary features for authentication. The low-frequency part of the image is encrypted using the proposed Binary Data Cyclic Encryption algorithm (BDCE) while the owner’s palmprint features are embedded for authentication of the data owner. The high-frequency data are randomized for compression by the CS and following encrypted by the Double Random Phase Encoding (DRPE). For the cloud services, authentication services depend on the key and palmprint features and the high computational compressed sensing reconstruction is implemented in cloud can reduce the user burden. For data users, a user should provide the correct key and right palmprint, and then obtain an image available from the cloud service. The algorithm has better quality compared with the common compressive sensing based algorithms and robust to noise and occlusion for using the discrete wavelet transform. What is more, theoretical analysis and empirical evaluations show that the proposed algorithm can resist to exhaustive attack, differential attack and classical attacks.

Image compression-encryption algorithm based on 2D compressive sensing and double random phase encoding

In this paper, an image compression and encryption algorithm based on 2D compressive sensing and double random phase encoding is proposed. Compared with traditional encryption algorithms, 2D compressive sensing can realize image compression and encryption at the same time, with high execution efficiency. Double random phase encoding can not only realize image encryption fast, but also has robustness. Moreover, combining 2D compressive sensing with double random phase encoding can obtain better encryption security. Simulation results show that this algorithm has better image compression performance, and can ensure security and robustness.

An Asymmetric Optical Cryptosystem of Double Image Encryption Based on Optical Vortex Phase Mask Using Gyrator Transform Domain

Background: Optical Vortex (OV) has attracted attention amongst many researchers. Paper proposes a nonlinear scheme of image encryption based on Optical Vortex (OV) and Double Random Phase Encoding (DRPE) in the Gyrator Transform (GT) domain under phase truncation operations. Objective: The amplitude and phase truncation operation in the image encryption generates two decryption keys and convert the method to nonlinear. It has also been proposed opto-electronically. Original image can only be decrypted with correct values of OV, GT rotation angles and Decryption Keys (DKs). Methods: A novel asymmetric image encryption scheme, using optical vortex mask has been proposed in view of amplitude and phase truncation operation. The scheme becomes more strengthened by the parameters used in the Optical Vortex (OV) and by taking the (n)th power operation in the encryption path and (n)th root operation in the decryption path. Results: It shows that for each of the encryption parameters, binary image has greater sensitivity as compared to the grayscale image. This scheme inflates the security by making use of OV-based Structured Phase Mask (SPM) as it expands the key space. The scheme has also been investigated for its robustness and its sensitivity against various attacks such as noise and occlusion attacks under number of iterations. Conclusion: This scheme provides solution to the problem of key space with the use of GT rotational angles and OV phase mask thus enhances the security. The scheme has been verified based on various security parameters such as occlusion, noise attacks, CC, entropy etc.

Optical image encryption based on quantum walks

In this paper, we propose a new optical encryption approach based on quantum walks and double random phase encoding technique. Quantum walks have been proven as an excellent tool for designing modern cryptographic mechanisms due to its ability to resist probable attacks from both digital and quantum computers. In the proposed approach, we use the alternate quantum walks (AQW) at two encryption stages. First, inner encryption and encoding by double random phase encoding (DRPE) which executed using permutation followed by substitution. Furthermore, AQW is adapted to generate two random masks for the DRPE process. Simulation-based validation of our proposed technique, including correlation, histogram, sensitivity, key space as well as noise and data loss analysis provide impetus to consider its use in applications in modern optical cryptosystems.

Security-enhanced optical cryptosystem using nonergodic scrambling phase mask.

Cryptanalysis revealed a security flaw in the double random phase encoding (DRPE) system, and the original image was recovered via a ciphertext-only attack. In this paper, a nonergodic scrambling phase mask (NESPM) is designed, and a security-enhanced cryptosystem is established by replacing the bonded random phase mask (RPM) in the DRPE system with the designed NESPM. The original image in the security-enhanced cryptosystem is optically scrambled at "macropixel" level by the bonded NESPM, instead of being diffused by the RPM, as in the DRPE system. Due to such a scrambling operation, the ergodic property of the Fourier-plane speckle pattern in the designed cryptosystem is removed, and the original image cannot be recovered via the attack. Experimental results demonstrate that the designed cryptosystem is resistant to the attack. Security enhancement is achieved.

Image Compression-Encryption Scheme via Fiber Specklegram-Based Compressive Sensing and Double Random Phase Encoding

An image compression-encryption scheme utilizing the combination of fiber specklegram-based compressive sensing (CS) and double random phase encoding (DRPE) was demonstrated. The original image is compressed and encrypted by CS and then re-encrypted by DRPE. The measurement matrices for CS are constructed from multimode fiber specklegrams resulting from modes excitation and interference, which show better performance compared with those based on Gaussian random variables. Since fiber specklegrams have strong dependence on configuration, such measurement matrix can be constructed either by one specklegram or by specklegrams from different launched wavelengths. The double-encrypted image demonstrated good safety and reliability in several common attacks and presented high key sensitivity, which indicates good performance of the proposed scheme.

Chaotic image encryption based on bidimensional empirical mode decomposition and double random phase encoding

In this paper, to enhance the security of double random phase encoding (DRPE), Lorenz system and bidimensional empirical mode decomposition (BEMD) are introduced into an image encryption process. By means of BEMD, the original grayscale image is decomposed into three sub-images, then they are diffused and confused by using the pseudorandom sequences generated by Lorenz system. At last, the three result images are encoded by using DRPE, we obtain the color ciphered image. Thorough experimental tests are carried out with detailed analysis, demonstrating the feasibility and high security of the new scheme.

Analysis of singular phase based on double random phase encoding using phase retrieval algorithm

We analyze the properties of the singular phase based on phase retrieval. The phase can be estimated from the result of the known-plaintext attack on a typical optical encryption technique, namely double random phase encoding. The key generated by the singular phase for decryption can be used to decrypt only the known ciphertext image used for the attack. However, it is not obvious whether any unknown ciphertext image can be decrypted using the singular key (a phase key image that has the singular property). Therefore, we prepared various ciphertext images by changing two parameters, namely the plaintext image and a random phase mask in the spatial plane, and analyzed the properties of the singular key by decrypting these unknown ciphertext images. The results show that when the unknown ciphertext images generated by changing only the plaintext image are decrypted, the known plaintext pattern is obtained. In contrast, when the unknown ciphertext images generated by changing only the random phase mask are decrypted, no pattern is obtained. These cases both indicate that cryptanalysis failed. Nevertheless, when the known plaintext pattern is obtained, it indicates that the correlation between the known and unknown random phase masks is high, giving the attacker an important clue.

Shift, rotation and scale invariant optical fingerprint verification system with double random phase encoding

Biometric features such as fingerprint images can be authenticated by not only computer algorithms but also optical systems. In previous works, double random phase encoding (DRPE) optical lens system is employed for fingerprint verification. However, such a system can yield authentication failure when the key is generated from a slightly distorted fingerprint image. In this work, a fingerprint image pre-processing scheme for DRPE fingerprint optical authentication system is proposed. Simulated experimental results demonstrate the proposed method has significantly better robustness to shift, rotation and scale variance than some of the conventional DRPE-based approaches.

Experimental optical encryption scheme for the double random phase encoding using a nonlinear joint transform correlator

We present a new experimental system for optical encryption using a nonlinear joint transform correlator (JTC) to implement the optical security technique of the double random phase encoding (DRPE). The DRPE, which is usually performed in a 4f-processor, encodes an image into a noisy distribution (encrypted image) by using two random phase masks (RPMs). In our experimental setup, the input plane of the JTC is fully encoded in phase and this plane contains two non-overlapping data functions (images). In the encryption step, the phase-encoded image to be encrypted and the two RPMs are placed in the input plane of the JTC with the purpose of obtaining the needed intensity distributions at the output plane to compute the encrypted image. The optical and numerical transformations are performed in the Fourier domain. A nonlinear operation is introduced to modify the joint power spectrum (JPS) of the JTC in order to reproduce exactly the same results of the DRPE. The experimental optical encryption scheme based on a three-step JTC is implemented by using an optoelectronic setup. The input plane of the JTC is optically implemented by means of a phase-only spatial light modulator (SLM). The decryption process is performed using a virtual optical system. Experimental and numerical results of the optical encryption and simulated decryption systems are presented, in order to show the feasibility of the proposed security system.

Optical encryption based on double random-phase encoding: secure versus unsecure variants.

A smart brute-force double random-phase encoding attack is presented that takes advantage of an unreported vulnerability: the smoothness of mean squared error (MSE) and correlation coefficient (CC) curves in a key-sensitivity analysis. The vulnerability reported here is made visible in a key-sensitivity analysis. It is shown that a modular arithmetic pre-coding provides significant robustness against this form of attack because the pre-coding creates a highly nonlinear, highly oscillatory MSE and CC curve in the key space. Knowledge of this new vulnerability and how to prevent this in the first place provides a better understanding of the robustness of various double random-phase encoding designs.

Cancelable face and fingerprint recognition based on the 3D jigsaw transform and optical encryption

Biometric systems are widely used now for security applications. Two major problems are encountered in biometric systems: the security problem and the dependence on a single biometric for verification. The security problem arises from the utilization of the original biometrics in databases. So, if these databases are attacked, the biometrics are lost forever. Hence, there is a need to secure original biometrics by keeping them away from utilization in biometric databases. Cancelable biometrics is an emerging security trend in the field of biometric authentication. Cancelable biometric systems depend on the transformation of biometric features into new formats so that users can replace their biometric templates in the same or different systems. In this paper, we present a proposed cancelable face and fingerprint recognition algorithm based on the 3D jigsaw transform and optical encryption. The algorithm adopts the Fractional Fourier Transform (FRFT) in the optical encryption scheme with a single random phase mask. This structure can be implemented all optically with a single lens. The proposed cancelable biometric recognition algorithm employs an optical image encryption scheme that depends on two cascaded stages of 2D-FRFT with separable kernels in both dimensions. The two stages are separated with a random phase mask. A preceding bit plane permutation process is performed on the obtained biometrics prior to the FRFT operation to achieve a high level of security. To validate the proposed algorithm for cancelable biometric recognition, different sets of face and fingerprint images are used. A comparative study is presented between the proposed algorithm and the optical Double Random Phase Encoding (DRPE) algorithm. The simulations results obtained for performance evaluation show that the proposed algorithm is safe, reliable, and feasible. It has good encryption and cancelability that reveal good performance.

Generalized optical encryption framework based on Shearlets for medical image

The security of medical image data for transmission and storage is a critical issue. Texture information of medical images is important for diagnosis. Since Shearlets is particularly effective in characterizing texture information, in this paper, we propose a generalized optical encryption framework based on Shearlets and double random phase encoding (DRPE) especially for medical images. In the proposed encryption framework, the secret medical image is first decomposed into n sub-images with shearlet transform. Then, the sub-images or pixel positions are shuffled by scrambling algorithm. Subsequently, the shuffled sub-images are synthesized into one image. Finally, the synthesized image is encoded with DRPE. The security level of the proposed encryption framework can be improved by changing the parameters of shearlet transform and selecting different methods for scrambling pixels and synthesizing multiple images to single image. Extensive simulation results have shown the performance of the proposed optical encryption framework. The proposed encryption framework can be improved along with novelty scrambling method and reversible synthesize methods.

Learning-based attacks for detecting the vulnerability of computer-generated hologram based optical encryption.

Optical encryption has attracted wide attention for its remarkable characteristics. Inspired by the development of double random phase encoding, many researchers have developed a number of optical encryption systems for practical applications. It has also been found that computer-generated hologram (CGH) is highly promising for optical encryption, and the CGH-based optical encryption possesses remarkable advantages of simplicity and high feasibility for practical implementations. An input image, i.e., plaintext, can be iteratively or non-iteratively encoded into one or several phase-only masks via phase retrieval algorithms. Without security keys, it is impossible for unauthorized receivers to correctly extract the input image from ciphertext. However, cryptoanalysis of CGH-based optical encryption systems has not been effectively carried out before, and it is also concerned whether CGH-based optical encryption is sufficiently secure for practical applications. In this paper, learning-based attack is proposed to demonstrate the vulnerability of CGH-based optical security system without the direct retrieval of optical encryption keys for the first time to our knowledge. Many pairs of the extracted CGH patterns and their corresponding input images (i.e., ciphertext-plaintext pairs) are used to train a designed learning model. After training, it is straightforward to directly retrieve unknown plaintexts from the given ciphertexts (i.e., phase-only masks) by using the trained learning model without subsidiary conditions. Moreover, the proposed learning-based attacks are also feasible and effective for the cryptoanalysis of CGH-based optical security systems with multiple cascaded phase-only masks. The proposed learning-based attacking method paves the way for the cryptoanalysis of CGH-based optical encryption.

Symmetric cryptosystem to secure images utilizing chaotic deterministic phase mask in Fresnel transform domain employing singular value decomposition

This research work proposes a lens less secure symmetric image encryption system using a novel chaotic deterministic phase mask (CDPM) in the light of Fresnel transform (FrT) deploying singular value decomposition (SVD). Here, two CDPM’s are used instead of random phase masks (RPM) in Fresnel transform based double random phase encoding (DRPE) scheme with the addition of SVD. The variation of CDPM and SVD amplifies the security of the Fresnel transform based DRPE in comparison to the traditional one. The key space of the proposed cryptosystem is large constituting the complex phase masks (CDPM), the order of SVD, the distance between the significant planes and the wavelength of the Fresnel transform. The system is simple, fast and tough to break. The encrypted image can be sent over an unsecured channel since the security lies in the secrecy of the keys. The enhanced framework resists the possible attacks on traditional DRPE and therefore reinforces DRPE security. The utilization of a novel complex mask that gives advantages of both chaotic map and deterministic phase mask improves the quality of the cryptosystem. The performance analysis and the result outcomes exhibit the efficacy of the designed cryptosystem.