Nonlinear image encryption and authentication based on phase truncation and reservation in the cylindrical diffraction domain

ABSTRACT

A nonlinear image encryption and authentication strategy based on phase truncation and reservation (PTR) in cylindrical diffraction domain is proposed. First, the cylindrical diffraction spectrum of the input image is sparsely sampled. Then, its sparse presentation is disintegrated into phase part and real-valued amplitude part with the help of the PTR, both of which are essential for decryption and authentication. The decrypted image reveals little information of the original input image visually. Finally, a nonlinear correlation is resorted to authenticate the decrypted image with the input image. In the proposed strategy, the parameters of cylindrical diffraction are utilized to enhance its security. The cylindrical diffraction has the nonlinear characteristics, while the PTR outputs real-valued cyphertext, which further breaks the linearity. Furthermore, the percentage of extracted pixels in sparse sampling needs not to be identified purposely. Numerical simulations demonstrate the feasibility and effectiveness of the proposed scheme.

KEYWORDS:

• Nonlinear image encryption
• image authentication
• cylindrical diffraction
• phase truncation and reservation
• sparse sampling

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported in part by the Doctoral Research Foundation of Hunan University of Science and Technology [grant number E51974] and the Scientific Research Foundation of Hunan Provincial Education Department of China [grant number 19B199].