To provide a method which clarifies a candidate set via selection of the desired interpretation of a character image by setting a distance within its allowable range against different types of binarization of a sample image for each candidate image.

An image recognition system 120 includes a scanner 126, a display 128, a memory 132 for storing software instructions executed by a CPU 122, etc. The memory 132 includes a software object and a module which includes a normalization unit 134, a distance calculation unit 136, a sorting unit 138 and a clarification unit 140. A sample image 142, which is stored via the memory 132, is recognized when the size of the image 142 is normalized into the size of a reference image 146, and a set of images 146 is decided by a set of candidate images 147. The distance for each image 147 is set within its allowable range against different types of binarization of the image 142.