1. An image recognition apparatus, comprising: a storage unit storing a threshold calculated based on a blur level of a normalized image, the normalized image being obtained by normalizing an image in a predetermined size; a measurement unit measuring a blur level of an image; a comparison unit comparing the blur level measured in the measurement unit with the threshold; an image processing unit applying to the image a blurring filter which increases the blur level when the blur level measured in the measurement unit is smaller than the threshold, and applying to the image a deblurring filter which decreases the blur level when the blur level measured in the measurement unit is larger than the threshold; and a recognition unit recognizing the image from features of the image processed in the image processing unit.