Abstract
The paper presents an opto-double color image cipher using two dimensional (2D) chaotic Arnold transform (AT) as a preprocessing scrambling stage and 2D chaotic Logistic adjusted Sine map (LASM) phase masks in the Fresnel (Fr)-based Hartley Transform (HT). In the proposed opto-double color image cipher, the 2D chaotic LASM is utilized to create chaotic phase masks. The color plainimage red, green and blue channels are firstly scrambled with 2D chaotic AT. Then, the scrambled color plainimage red, green and blue R-G-B channels are modulated using the 2D chaotic LASM phase mask and transformed with the Fr-based HT. The transformed complex R-G-B channels distributions are secondly scrambled with the 2D chaotic AT, modulated secondly with the 2D chaotic LASM phase mask and transformed with Fr-based HT. The utilization of 2D chaotic LASM phase masks in addition to the 2D chaotic AT provides efficient key administration and communication. Also, optical geometric parameters are considered as extra additional keys that enhances the secrecy of the proposed scheme. A comprehensive security study is employed for the proposed scheme and test results verifies and ensures that the proposed scheme is highly immune and resistant against most potential attacks.