1. An image processing device comprising: a memory for storing a template for pattern matching and an image of a subject; a display unit for displaying the template and the image of the subject; a region specifying device for specifying a region which includes a first region detected by the pattern matching and a second region including an actually desired pattern to be detected in the image of the subject; and an image processing unit for computing first degree of coincidence between the first region and the template and second degree of coincidence between the second region and the template, wherein the display unit displays the first degree of coincidence and second degree of coincidence.