Feature value extraction apparatus and feature value extraction method

A feature value extraction apparatus is provided that includes an image input unit that receives an input of an image, and a converted image generation unit that converts the input image into at least one converted image for extracting a feature value of the input image. The apparatus also includes a feature value generation pattern holding unit that stores a feature value generation pattern that includes a plurality of comparison pairs of unit positions for comparing unit values in a unit array in which units, each of which includes at least one pixel, are arranged. The apparatus further includes a feature value extraction unit that compares the unit values corresponding to the comparison pairs through referring to the feature value generation pattern with respect to the converted image, and extracts the feature value of the converted image.