Image encryption by visual cryptography with error analysis

Abstract

In composite cryptography, a test image is encrypted into a set of other images, which later can be combined in a particular manner to recover the hidden test image. An increase in image resolution decreases the ease of decoder alignment and increases computational time. In this work, a method to quantify the quality of the recovered image is proposed by the introduction of a quantifier called the error ration. Results indicate that the error ration monotonically decreases as the resolution increases. The method facilitates enhanced image quality at reduced computational time.