In an image recognition method of recognizing a plurality of images from an
input image, the plurality of images to be recognized including at least
one of a specific image and images provided by rotating the specific
image, the method includes the steps of: preparing at least one of mask
areas on a window area for each image to be recognized, the window area
being structured by cells which are arrayed in two-dimensionally, the cell
being formed of at least one pixel, the mask area being structured by at
least one of the cells and corresponding to an area representing a feature
of the image to be recognized; first determining whether or not the image
to be recognized exists based on the result of subjecting pixel density
values of the input image in the mask area to operation for each image to
be recognized; and second determining whether or not any of the plurality
of images to be recognized exists in the window area based on the
determination result of the first determining step.