<p>Provided is an image processing device which can obtain an image having an improved gradation irregularity while maintaining the image in a dark or a bright state. The image processing device includes: a conversion unit which converts input gradation of a target pixel and peripheral pixels into an ideal index value by using an ideal mapping curve; an extraction unit which extracts the target index value corresponding to the ideal index value of the target pixel and the peripheral pixels by using the target mapping curve; a ratio calculation unit which calculates an ideal ratio; and a correction unit which makes corrections so that the target ratio is identical to the ideal ratio and the target index value of the target pixel is bright, thereby obtaining a correction index value.</p>
