Pixel interpolation apparatus, method for pixel interpolation, and image reading apparatus using the same

摘要

An embodiment has: weighting interpolation section for obtaining a pixel value for a missing pixel by a one-dimensional weighting interpolating method, using pixels in the vicinity of the missing pixel as reference pixels, and for generating a primarily interpolated image signal including the interpolated pixel value in place; frequency decomposition section for decomposing the primarily interpolated image signal into frequency components; halftone dot extraction sections for obtaining a halftone dot degree indicating a degree for the vicinity of the missing pixel to be in the halftone dot region, by using higher ones of these frequency components; correction value calculation section for calculating a correction value for the missing pixel, by using lower ones of these frequency components; and correction section for correcting the pixel value of the missing pixel in the primarily interpolated image signal using the correction value depending on the halftone dot degree.