1. Improved decryption quality and security of a joint transform correlator-based encryption system.
- Author
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Vilardy, Juan M, Millán, María S, and Pérez-Cabré, Elisabet
- Subjects
- *
DATA encryption , *ALGORITHMS , *FOURIER transform optics , *NONLINEAR optics , *STATISTICAL correlation , *IMAGE quality in imaging systems - Abstract
Some image encryption systems based on modified double random phase encoding and joint transform correlator architecture produce low quality decrypted images and are vulnerable to a variety of attacks. In this work, we analyse the algorithm of some reported methods that optically implement the double random phase encryption in a joint transform correlator. We show that it is possible to significantly improve the quality of the decrypted image by introducing a simple nonlinear operation in the encrypted function that contains the joint power spectrum. This nonlinearity also makes the system more resistant to chosen-plaintext attacks. We additionally explore the system resistance against this type of attack when a variety of probability density functions are used to generate the two random phase masks of the encryption-decryption process. Numerical results are presented and discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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