Patent ID: 8305597

Claim:
An image recognition device comprising: an image reading means for reading image information from a document; an extraction means for extracting a plurality of marks included in the image information; a distance calculation means for calculating distances between the extracted plurality of marks; and a discrimination means for determining whether a specific mark, in which plural marks are arranged, exists in the image information by: determining that the specific mark exists in the image information upon determining that: the distances between the extracted plurality of marks correspond to distances between the plural marks of the specific mark, and a mirror-image relationship between positions of the extracted plurality of marks and the specific mark does not exist, wherein the mirror-image relationship indicates that the positions of the extracted plurality of marks correspond to positions of the plural marks of the specific mark mirrored across an axis, wherein the discrimination means includes a vector-product calculating means for calculating a vector product using two vectors, one vector directed from a first mark to a second mark and another vector directed from the first mark to a third mark, and wherein the discrimination means determines that the mirror-image relationship between positions of the extracted plurality of marks and the specific mark does not exist upon determining that the distances between the extracted plurality of marks correspond to the distances between the plural marks of the specific mark and the vector product corresponds to a vector product of the specific mark.