A multiple-image encryption scheme is proposed based on the phase retrieval process and phase mask multiplexing in the fractional Fourier transform domain. First, each original gray-scale image is encoded into a phase only function by using the proposed phase retrieval process. Second, all the obtained phase functions are modulated into an interim, which is encrypted into the final ciphertext by using the fractional Fourier transform. From a plaintext image, a group of phase masks is generated in the encryption process. The corresponding decrypted image can be recovered from the ciphertext only with the correct phase mask group in the decryption process. Simulation results show that the proposed phase retrieval process has high convergence speed, and the encryption algorithm can avoid cross-talk; in addition, its encrypted capacity is considerably enhanced.
© 2013 Optical Society of America
Fourier Optics and Signal Processing
Original Manuscript: April 2, 2013
Revised Manuscript: May 11, 2013
Manuscript Accepted: May 13, 2013
Published: May 31, 2013
Sui Liansheng, Xin Meiting, and Tian Ailing, "Multiple-image encryption based on phase mask multiplexing in fractional Fourier transform domain," Opt. Lett. 38, 1996-1998 (2013)