Super-resolution of imagery: understanding the basis for recovery of spatial frequencies beyond the diffraction limit

Since the formation of an image alters the recorded information content from that of the original object, there has been much interest and effort directed to processing the image so as to more closely match the original object. The paper examines credible methods for the reconstruction of spatial frequencies of the object that are greater than the diffraction limit spatial frequencies in the image. Processes that achieve the recreation of frequencies beyond the image passband are usually referred to as super-resolution algorithms. The ability to achieve super-resolution of an image is controversial, with prominent literature proclaiming it as not possible. However, the existence of algorithms that have demonstrated super-resolution in a number of different contexts has made it inescapable to conclude that super-resolution is possible. Understanding the basis of super-resolution also leads to understanding how the various algorithms for super-resolution function