Multiple-image encryption based on light-field imaging and gravity model

A new multiple-image encryption method based on a light-field imaging system and the gravity model is presented in this paper. An inverse process of light-field imaging was used for multiple-image encryption. The method first combined multiple images into one light-field image. It was then encrypted using the gravity model, which further improved the security. The structural parameters of the light-field imaging system and the different objective distances of each original image could be used as part of the secret keys. A refocusing reconstruction algorithm for the light-field image was used in the decryption process. Experiments and analyses have shown that the proposed scheme could easily be accessed and provides a large key space and high sensitivity in the key space. Furthermore, it is robust against occlusion attacks. Compared with the repeated use of gravity model alone, the proposed method offers enhanced statistical properties and efficiency benefits. The proposed encryption can be achieved by a computational way, which can eliminate the negative effects of hardware limitations and aberrations.