1. An image processing device comprising: a first flicker component calculation unit that calculates a flicker component of a first exposure image which is a photographed image of a first exposure time; a second flicker component calculation unit that calculates a flicker component of a second exposure image which is a photographed image of a second exposure time different from the first exposure time; a first exposure image flicker correction unit that performs flicker correction on the first exposure image by applying the flicker component of the first exposure image calculated by the first flicker component calculation unit and generates a flicker-corrected first exposure image; and a second exposure image flicker correction unit that performs flicker correction on the second exposure image by applying the flicker component of the second exposure image calculated by the second flicker component calculation unit and generates a flicker-corrected second exposure image, wherein the second flicker component calculation unit calculates the flicker component of the second exposure image as a linear sum of the flicker components of the first exposure images calculated by the first flicker component calculation unit.