A first region that includes a target pixel and extends in a first direction, and multiple regions and that are obtained by shifting the first region by a predetermined amount in direction perpendicular to the first direction are set. A first correction value is obtained using multiple pixel values selected in the regions based on correlation values indicating a degree of correlation with the target pixel. The value of the target pixel is corrected using a correction value obtained from the first correction value and the pixel value selected in the first region, with a weight based on the sizes of the correlation value corresponding to the first correction value and the correlation value corresponding to the pixel value selected in the first region.