1. An apparatus for processing an image, comprising: a determiner configured to determine an area corresponding to a white-saturation area comprised in a raw image based on raw data representing the raw image, wherein the raw image is obtained by photographing and is not processed; and a converter configured to selectively perform an image space frequency distribution conversion on a portion of the raw data that corresponds to the determined area corresponding to the white-saturation area, wherein the converter is further configured to reduce luminance changes of pixels which are not a preset reference pixel in the area corresponding to the white-saturation area.