Optical Engineering

Enhancement of interference-based image encryption using chaotic permutation and phase-blend operation

Qu Wang, Jinyun Zhou, Qing Guo

Published Apr 18, 2012• 4 citations

Abstract

In conventional interference-based optical encryption schemes, a potential cracker can retrieve partial information (silhouette) of the secret image using only one phase-only mask (POM). We resolve this drawback using a phase-blend operation and piecewise linear chaotic map (PWLCM) to further encode the POMs. One cannot recover a secret image visibly when inverse phase-blend operation and inverse chaotic permutation are not carried out with the correct decryption keys. Chaotic parameters of PWLCM, and random phase-angle function in the phase-blend operation enlarge the key space and improve the security of the proposed system greatly. Numerical simulations and optoelectronic experiments are performed to verify the effectiveness of the proposed scheme.

DOI: 10.1117/1.oe.51.4.048201

Related papers

Color image encryption based on enhanced optical interference with different diffraction distances and linear phase color-blend

Lei Liu, Mingguang Shan, Zhi Zhong +1 more

Abstract We develop a novel method to encrypt a color image by combining enhanced optical interference with phase retrieval algorithm and linear phase color-blend (LPCB). In this method, the original color image is encoded into three phase only masks (POMs) with different Fresnel diffraction distances and one fixed random phase mask (RPM). For the decryption in an optical interference system, the three individual POMs are placed in the red, green and blue channels, respectively, and the RPM is placed in the public channel. Only if the right POMs and RPM are fixed in their positions properly, one could achieve the expected information. Compared with traditional interference based color image method, our method eliminates the silhouette problem fully. LPCB is also introduced to modulate the phase value of each pixel of the three POMs to further enhance the security. Numerical simulation results are presented to illustrate the feasibility and effectiveness of the proposed scheme.

Journal of OpticsNov 14, 20183 citations

Optical image encryption using a jigsaw transform for silhouette removal in interference-based methods and decryption with a single spatial light modulator

Pramod Kumar, Joby Joseph, Kehar Singh

Interference-based optical encryption schemes have an inherent silhouette problem due to the equipollent nature of the phase-only masks (POMs) generated using an analytical method. One of the earlier methods suggested that removing the problem by use of exchanging process between two masks increases the computational load. This shortcoming is overcome with a noniterative method using the jigsaw transformation (JT) in a single step, with improved security because the inverse JT of these masks, along with correct permutation keys that are necessary to decrypt the original image. The stringent alignment requirement of the POMs in two different arms during the experiment is removed with an alternative method using a single spatial light modulator. Experimental results are provided to demonstrate the decryption process with the proposed method.

Applied OpticsApr 19, 2011146 citations

Interference-based optical image encryption with silhouette removal by amplitude modulation

Wang Yong, Chenggen Quan

Abstract Interference-based optical encryption schemes have an inherent silhouette problem, due to the equipollent nature of the phase-only masks generated from an analytical method. We propose a new interference-based optical image encryption with silhouette removal by amplitude modulation. Different from the previous methods, which require time-consuming iterative computation or post-processing of the phase-only masks for silhouette removal, the proposed method can resolve the problem by adding an amplitude modulating operation on the original image. The introduction of the amplitude modulator can significantly enhance the security of the system, and the silhouette problem inherent in a conventional interference-based encryption method is fully resolved. The design and parameter choice of the amplitude modulator is discussed. Numerical simulations are presented to verify the validity of the proposed method.

Journal of OpticsAug 30, 201712 citations

Hybrid attack for the optical cryptosystem based on interference and additional fixed phase masks

Yi Xiong, Jiashuai Liu, Hongjie Xu +1 more

This paper presents a security analysis of the optical image encryption scheme based on interference and fixed phase masks. Unlike the traditional interference-based scheme, which uses only one phase-only mask (POMs) generated during the encryption process as the private key, the improved system incorporates fixed phase masks as the additional private keys. While it appears that the security strength of the interference-based scheme is enhanced by expanding the key space, our analysis reveals that these fixed phase masks are independent of the plaintext and can be recovered through a known-plaintext attack (KPA). Once these additional private keys are obtained, the number of unknown private keys is reduced to one, allowing the plaintext information encrypted by the improved interference-based scheme to be recovered from any arbitrarily given ciphertexts without any knowledge of the private key. To show the vulnerability of this cryptosystem, we propose a hybrid attack combining the KPA and ciphertext-only attack (COA) which can break the improved interference-based cryptosystem. Numerical simulations have been performed to confirm the feasibility and effectiveness of the proposed hybrid attack.

Applied OpticsDec 9, 20251 citation

Interference-based multiple-image encryption and authentication via lateral shift multiplexing and sparsification

Guangyu Luan, Caojun Huang, Dong‐Xin Wang

We report a novel optical method of interference-based multiple-image encryption and authentication via lateral shift multiplexing and sparsification. We encode multiple original images into two ciphertexts only containing partial information of the multiple images when the secret key generated randomly is laterally movable within a predefined interval, and we analytically derive the two other keys of each original image. Information discrimination for each original image as well as its silhouette is still prohibited in spite of the utilization of one, two, three, or even four masks for decryption. The three secret keys of each original image signiﬁcantly improve the security of the proposed method, and binary amplitude masks are included in the decryption and authentication procedure. Moreover, the proposed scheme completely eliminates the cross-talk problem and destroys any high correlation between the plaintexts and ciphertexts. Numerical simulations are executed to prove the effectiveness and security of this scheme.

Journal of Modern OpticsNov 13, 20210 citations

Optical Image Encryption with Silhouette Removal

Xingqiang Yang

A novel optical encryption system based on non coherent superposition is proposed. In this system, the original image is hidden into three Phase Only Masks (POMs). One of the phase masks is generated by computer while another two are obtained analytically. For decryption, the diffraction filed of the three POMs is superposed by utilizing the beam splitters. The intensity of the superposition field, which is exactly the original image, could be recorded by CCD camera. Compared with the earlier interference-based method, our approach is simple and easy to be realized by optical elements. Moreover, the silhouette problem existing in the earlier method with two POMs can be resolved in our method, thus the security of the method is further improved. Simulation results are presented to verify the validity of the proposed approach.

Jan 1, 20120 citations