The Property of Frequency Shift in 2D-FRFT Domain with Application to Image Encryption

TL;DR

This paper explores the frequency shift property in 2D-FRFT domain, demonstrating its invariance in image reconstruction and its potential to improve the robustness of image encryption against attacks.

Contribution

It reveals the frequency shift-invariance of image magnitude in 2D-FRFT, enhancing encryption robustness, which is a novel insight in multimedia security.

Findings

Magnitude of image reconstruction is frequency shift-invariant in 2D-FRFT.

The property improves robustness of image encryption against frequency shift attacks.

Experimental results confirm effectiveness of the property in security applications.

Abstract

The Fractional Fourier Transform (FRFT) has been playing a unique and increasingly important role in signal and image processing. In this letter, we investigate the property of frequency shift in two-dimensional FRFT (2D-FRFT) domain. It is shown that the magnitude of image reconstruction from phase information is frequency shift-invariant in 2D-FRFT domain, enhancing the robustness of image encryption, an important multimedia security task. Experiments are conducted to demonstrate the effectiveness of this property against the frequency shift attack, improving the robustness of image encryption.