Encrypting 2D/3D image using improved lensless integral imaging in Fresnel domain

• 2D/3D image encryption by utilizing the improved lensless integral imaging.
• Distributed memory characteristic of elemental images provides high robustness.
• Multiple dimensional key spaces improve the security of encryption.

We propose a new image encryption technique, for the first time to our knowledge, combined Fresnel transform with the improved lensless integral imaging technique. In this work, before image encryption, the input image is first recorded into an elemental image array (EIA) by using the improved lensless integral imaging technique. The recorded EIA is encrypted into random noise by use of two phase masks located in the Fresnel domain. The positions of phase masks and operation wavelength, as well as the integral imaging system parameters are used as encryption keys that can ensure security. Compared with previous works, the main novelty of this proposed method resides in the fact that the elemental images possess distributed memory characteristic, which greatly improved the robustness of the image encryption algorithm. Meanwhile, the proposed pixel averaging algorithm can effectively address the overlapping problem existing in the computational integral imaging reconstruction process. Numerical simulations are presented to demonstrate the feasibility and effectiveness of the proposed method. Results also indicate the high robustness against data loss attacks.