Color information security system using Arnold transform and double structured phase encoding in gyrator transform domain

A new method for encoding color information based on Arnold transform and double structured phase encoding in gyrator transform domain is introduced. The phase function of Fresnel zone plate is used as structured phase mask. Prior to the encryption, the decomposed red, green, and blue components of the color image are independently permutated by Arnold transform, transmitted through structured phase mask, and then performed gyrator transform. The system parameters of Arnold transform, structured phase mask, and gyrator transform in each component image provide as encryption keys of the scheme. The proposed system avoids problems arising from misalignment. The optical implementation has also been proposed. Numerical simulations’ results are presented to verify the security, validity, and possibility of the proposed approach.

► Arnold transform and structured mask in gyrator domain are used in image encoding.
► Parameters of structured mask and two transforms in each channel are encoding keys.
► The optical implementation of encryption technique has been presented.
► The proposed system avoids problems arising from misalignment.
► Numerical simulations are demonstrated to verify the feasibility of the technique.