High-performance compression and double cryptography based on compressive ghost imaging with the fast Fourier transform

• We propose an optical encryption based on compressive ghost imaging with fast Fourier transform.
• We demonstrate the feasibility of the proposed optical encryption by experiment and numerical simulation. Further we test the security of the proposed scheme against chosen-plaintext attack and ciphertext-only attack.
• We verify the compression of the method proposed in the paper with the amount of information transmitted, because of the combination of fast Fourier transform and compressive sensing, the method achieve the high performance on the compression, further reduce the storage space.

To solve the problem that large images can hardly be retrieved for stringent hardware restrictions and the security level is low, a method based on compressive ghost imaging (CGI) with Fast Fourier Transform (FFT) is proposed, named FFT-CGI. Initially, the information is encrypted by the sender with FFT, and the FFT-coded image is encrypted by the system of CGI with a secret key. Then the receiver decrypts the image with the aid of compressive sensing (CS) and FFT. Simulation results are given to verify the feasibility, security, and compression of the proposed encryption scheme. The experiment suggests the method can improve the quality of large images compared with conventional ghost imaging and achieve the imaging for large-sized images, further the amount of data transmitted largely reduced because of the combination of compressive sensing and FFT, and improve the security level of ghost images through ciphertext-only attack (COA), chosen-plaintext attack (CPA), and noise attack. This technique can be immediately applied to encryption and data storage with the advantages of high security, fast transmission, and high quality of reconstructed information.