Double-image encryption without information disclosure using phase-truncation Fourier transforms and a random...

Area of Science:

• Cryptography
• Image Processing
• Information Security

Background:

• Phase-truncation-based cryptosystems face risks of unintended information disclosure.
• Existing methods like imaginary part truncating or varying phase keys are insufficient to prevent data leakage.

Purpose of the Study:

• To propose a secure encryption technique that eliminates the risk of information disclosure in phase-truncation cryptosystems.
• To enhance the security of image encryption against sophisticated attacks.

Main Methods:

• A nonlinear spatial and spectral encoding technique utilizing a random amplitude mask (RAM) was developed.
• The proposed method involves a two-layer security process controlled by the RAM.
• Spatial encoding of plaintext images and simultaneous encryption of images and keys were implemented.

Main Results:

• The proposed random amplitude mask (RAM) based encryption effectively prevents information disclosure.
• The hybrid encryption system maintains the trapdoor one-way function property of phase truncation.
• Numerical results confirm the feasibility and high effectiveness of the proposed algorithm.

Conclusions:

• The novel nonlinear spatial and spectral encoding technique significantly improves the security of phase-truncation cryptosystems.
• This method offers a robust solution against attacks that have previously compromised similar systems.
• The encryption algorithm provides enhanced security and data protection for digital images.