Utilizing Quality Measures in Evaluating Image Encryption Methods

The metrics or measures used in evaluating image quality usually serve applications that aim at enhancing image appearance or at preventing the image quality from degrading after image processing operations. On the other hand, the main goal of cryptography applications is to produce unrecognizable encrypted images that can resist various kinds of attacks. Furthermore, cryptography must consider extra measures such as keyspace and key sensitivity. This paper discusses the most useful quality metrics used in image cryptography and explains the type of values that indicate good encryption according to each metric. These metrics include statistical analysis measures, sensitivity measures, and other metrics.