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.

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

An image encryption algorithm based on chaotic system and compressive sensing

Color image encryption based on hybrid hyper-chaotic system and cellular automata

A visually secure image encryption scheme based on compressive sensing

A fast image encryption algorithm based on compressive sensing and hyperchaotic map

Image compression and encryption scheme based on 2D compressive sensing and fractional Mellin transform

Disclosed is an image encryption method based on two-dimensional compressed sensing and non-linear fraction Mellin transform Part of Hadamand matrix built through a chaotic system serves as a measurement matrix, projection measurement is carried out on an original image subjected to two-dimensional discrete cosine transform in two orthogonal directions to obtain a measurement value, compression encryption of the image is realized, and the defect of a too large data amount after fraction Mellin transform is carried out on the image is overcome; non-linear fraction Mellin transform is carried out on the measurement value according to an annular range to obtain a ciphertext, and the problem that a linear compressed sensing encryption system is low in safety is resolved The initial value of the chaotic system and the transform order of fraction Mellin transform serve as the main secret key, and the central coordinates of coordinate transform and inner radius and outer radius of the transform implementation area serve as a secondary secret key The two-dimensional compressed sensing technology and non-linear fraction Mellin transform are effectively combined, the consumption amount of the secret keys is small, the secret key space is large, and high safety is realized

Image encryption method based on two-dimensional compressed sensing and non-linear fraction Mellin transform

This paper theoretically investigates a secondary-encryption optical chaotic communication system scheme based on an optical injection structure with single optical feedback and dual-dispersion optical feedback lasers. In the scheme, a fiber reflector (FR) and Fabry–Perot interferometer (FPI) are selected as the laser feedback cavity and effectively conceals time delay signatures (TDSs) of the generated chaotic signals. By switching the responding laser connected to the driving laser with the message feeding method, messages directly participating in the process of encryption signal generation are avoided to generate the first encrypted chaotic sequence that can characterize a message. Subsequently, chaotic phase disturbance technology is used to complete the secondary encryption. By virtue of the spectral broadening effect of chaotic phase disturbance, the message rate and the randomness of the encrypted signal can be effectively enhanced. We use the synchronous power error to decrypt the message at the receiver, which simplifies the system structure and realizes the scheme with low hardware costs. The proposed scheme overcomes the shortcomings of existed schemes, which generate chaotic signal sensitive to channel noise and have complex system structures. In addition, the proposed scheme shows good robustness in terms of handling noise for transmitting digital signals, a bit error rate (BER) of 6.7 × 10 −4 at a simulation signal-to-noise ratio of 10 dB, and good application prospects in harsh transmission environments, such as submarine optical fiber transmission. • A secondary encryption optical chaotic communication system is proposed, which show good robustness in terms of handling noise for transmitting digital signals. • By switching the responding laser connected to the driving laser as a message feeding method,the security of the system can be improved greatly. • The dispersion characteristic of F P I is used to widen the time delay signature pulse. • A bit error rate of 6.7×10 -4 is achieved at the signal-to-noise ratio of 10dB in the simulation. 

Haolin Li

Papers

Image compression and encryption scheme based on 2D compressive sensing and fractional Mellin transform

Image encryption method based on two-dimensional compressed sensing and non-linear fraction Mellin transform

Secondary-encryption optical chaotic communication system based on one driving laser and two responding lasers