Patent ID: 7386172

Claim:
An image recognition method for detecting a specific pattern in input image data, comprising: detecting, from the input image data, regions similar to a predetermined number of characteristic regions that are structural components of the specific pattern; storing position information of each of the detected characteristic regions; calculating distance values corresponding to distances between the detected characteristic regions, on the basis of the stored position information; calculating a degree of coincidence between a vector, which is formed by selecting a predetermined number of values from the calculated distance values between the characteristic regions, and a predetermined reference vector having the same number of orders; determining whether a region including the predetermined number of characteristic regions is a region of the specific pattern by comparing the calculated degree of coincidence with a predetermined threshold; calculating a value corresponding to an inner product of the two vectors when the degree of coincidence between the two vectors is calculated; calculating values corresponding to magnitudes of the two vectors; and dividing the value corresponding to the inner product by a product of the values corresponding to the two magnitudes.