1. An image processing apparatus comprising: a segmentation unit, arranged to segment an input image into a plurality of regions as sets of pixels having similar feature amounts; a calculator, arranged to calculate a size evaluation value V of an apparent size of each region segmented by the segmentation unit based on a number of pixels S and a shape of the each region, wherein the apparent size indicates a visual size of the region in the input image; and a corrector, arranged to perform chroma emphasis correction on the input image to weaken correction as a region has a larger size evaluation value V, wherein the calculator calculates the size evaluation value V using a dimension H in a vertical direction and a dimension W in a horizontal direction of the region as the shape, and a numerical formula which uses the number of pixels S, the dimension H, and the dimension W, so that the size evaluation value V grows large when a difference between the dimension H and the dimension W becomes small.