Method of Asymmetric Optical Encryption of Images Using Spatially Incoherent Illumination
The method of asymmetric encryption of images based on the double optical encryption with spatially incoherent illumination is presented. Numerical simulations of the presented method in various modifications are carried out and their efficiency is estimated. The modification providing the best balance between maintaining the advantages peculiar to the optical encryption and quality of the decoded images is chosen. In this case the value of the normalized standard deviation (NSTD) of the decoded image from original one for asymmetric encryption differs no more than by 8% from NSTD of standard optical encryption with spatially incoherent illumination.
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