Feature extraction device, feature extraction method, and feature extraction program

摘要

Device (10) comprises: a comparison object pixel acquisition unit (433) which acquires pixel values of a plurality of comparison object pixels which, when each pixel of an image is designated as a pixel of interest, and a ring-shaped region with the pixel of interest being designated as the center thereof being designated a vicinity region, said comparison object pixels are included in the vicinity region; a pixel difference calculation unit (434) which calculates the difference between the pixel value of the pixel of interest and the pixel values of each comparison object pixel; and a local binary pattern generation unit (435) which generates a local binary pattern for each pixel. A plurality of vicinity regions are present for each pixel of interest, and the distance of the vicinity regions are established on the basis of the spatial frequency characteristics of a lens with which the image is photographed.

主权项

1. A feature extracting apparatus comprising:
a receiver that receives a window region image which is a partial region of a target image taken through a lens; and a control circuitry, wherein the control circuitry is operative to: set, for each of a plurality of pixels included in the window region image, a pixel as a pixel of interest and acquire pixel values of a plurality of comparison target pixels included in an annular neighborhood region having the pixel of interest at its center; calculate a difference between the pixel value of the pixel of interest and the pixel value of each of the comparison target pixels; and generate, for each of the plurality of pixels, a local binary pattern indicating, using bit values, whether the difference between the pixel value of the pixel and the pixel value of each of the comparison target pixels is equal to or greater than a predetermined threshold, wherein a plurality of the neighborhood regions are present for each of the pixels of interest, and a distance between the plurality of neighborhood regions is determined based on spatial frequency characteristics of the lens.