Applied Optics

Evaluations of phase-only double random phase encoding based on key-space analysis

Kazuya Nakano, Masafumi Takeda, Hiroyuki Suzuki, Masahiro Yamaguchi

Published Feb 13, 2013• 14 citations

Abstract

Although initial research shows that double-random phase encoding (DRPE) is vulnerable to known-plaintext attacks that use phase retrieval algorithms, subsequent research has shown that phase-only DRPE, in which the Fourier amplitude component of an image encrypted with classical DRPE remains constant, is resistant to attacks that apply phase retrieval algorithms. Herein, we numerically analyze the key-space of DRPE and investigate the distribution property of decryption keys for classical and phase-only DRPE. We determine the difference in the distribution property of successful decryption keys for these DRPE techniques from the numerical analysis results and then discuss the security offered by them.

DOI: 10.1364/ao.52.001276

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