Quantum cryptographic algorithm for color images using quantum Fourier transform and double random-phase encoding

A novel encryption/decryption method for color images is proposed, in which quantum Fourier transform (QFT) and double random-phase encoding (DRPE) techniques have been used. The encryption process can be realized by performing two secret random-phase encoding operations respectively in the input and the QFT planes. Because all quantum operations are invertible, the decryption process is the inverse of the encryption process. Supported by detailed numerical simulation and theoretical analysis, the method has clarified its robustness, security and computational complexity over its classical counterpart. And it opens the door for introducing color image encryption into quantum scenarios.