Single-channel color image encryption using a modified Gerchberg-Saxton algorithm and mutual encoding in the Fresnel...

Area of Science:

• Optics and Photonics
• Information Security
• Image Processing

Background:

• Traditional double random phase encoding (DRPE) for image encryption can be complex.
• Existing methods may require intricate optical setups and multiple components.
• Secure and efficient encryption of color images remains a challenge.

Purpose of the Study:

• To propose a compact and simplified single-channel color image encryption system.
• To enhance security through novel use of modified Gerchberg-Saxton algorithm (MGSA) and mutual encoding.
• To enable efficient holographic recording and transmission of encrypted data.

Main Methods:

• Utilizing the modified Gerchberg-Saxton algorithm (MGSA) to generate phase-only functions (POFs) as encryption keys.
• Implementing mutual encoding in the Fresnel domain for encryption.
• Employing a single color component for encryption, reducing data size.

Main Results:

• A more compact and simple color encryption system was achieved.
• The system enables recording and transmission of a single grayscale ciphertext using holographic recording.
• Lensless optical setup simplifies implementation and enhances security with system parameters and wavelength as additional keys.

Conclusions:

• The proposed MGSA-based encryption offers a secure, efficient, and simplified approach to color image encryption.
• The lensless, compact design is practical for implementation.
• The method demonstrates feasibility and effectiveness through numerical simulations.