Patent ID: 8639039

Claim:
An image processing apparatus comprising: an interface unit for acquiring a readout image produced by capturing an image formed on a medium; a storage unit for storing a plurality of templates generated by superimposing different amounts of blurring on a prescribed pattern contained in said image, and for storing the amounts of blurring superimposed on said plurality of templates, respectively; and a processing unit adapted to detect a pattern region where said prescribed pattern is located on said readout image, calculate the degree of matching between said pattern region and each of said plurality of templates and, based on said degree of matching, identify from among said plurality of templates a template that most closely matches said prescribed pattern located on said readout image, and estimate that the amount of blurring corresponding to said most closely matching template represents the amount of blurring superimposed on said readout image, wherein said plurality of templates include a first template generated by superimposing the amount of blurring on an element-displaced pattern which is a pattern formed in such a manner that when an image of said prescribed pattern is captured by an image capturing apparatus having an arrangement of light receiving elements, if a boundary between a first pixel having a first pixel value and a second pixel having a second pixel value larger than the first pixel value, the first and second pixels being contained in said prescribed pattern, falls on one of the light receiving elements, a value intermediate between the first pixel value and the second pixel value is taken as a corresponding pixel value corresponding to the one of the light receiving elements.