Optical multiple-image compression-encryption via single-pixel Radon transform.

Compression is a common operation in multiple-image encryption (MIE) schemes. For most of the existing MIE schemes, the compression process would lead to the waste of the detect data. In this paper, a novel MIE scheme based on the single-pixel Radon transform (RT) is proposed. In the encryption process, the single-pixel RT of each image from 0° to 180° is performed. This process can be realized by an optical setup. All Radon spectra are combined and encrypted by the asymmetric cryptosystem based on phase-truncated Fourier transforms (PTFT). To increase the security, the Arnold map and logistic map are used to scramble and diffuse the result of PTFT. Unlike conventional MIE schemes, there is no extra compression operation and data waste in the proposed method. The key sensitivity, the multiplexing capacity, and the security under various attacks are analyzed through simulation results. The optical experiment is also performed to demonstrate the feasibility of the proposed optical MIE scheme.