Multi-layer single-pixel imaging end-to-end optical image encryption

The secure transmission of image information is an essential issue in communication, but it is also important in situations where the transmission channel resources are limited, such as quantum transmission. We propose a multi-layer single-pixel imaging end-to-end optical encryption framework with the characteristic advantage of a small key storage space requirement. Compared with previous single-layer encryption methods, the proposed approach greatly expands the key space and enhances the difficulty of brute-force cracking. The framework encrypts the image when the imaging signal is measured, which avoids the risk of leaking the plaintext information in processing. Numerical simulations and experiments verify the feasibility and robustness of this method. The proposed method can encrypt images end-to-end in both spatial and frequency domains, offering a new framework for robust, affordable, and secure optical image encryption.