1. An image processing apparatus, comprising: a feature extracting portion that extracts a feature of a frequency characteristic of an input image; a correction amount calculating portion that calculates a correction amount of the frequency characteristic from the feature extracted by the feature extracting portion; and an image correcting portion that corrects the input image according to the correction amount calculated by the correction amount calculating portion, wherein the feature extracting portion divides the input image into a plurality of small regions and extracts an average of features of frequency characteristics of the plurality of small regions over an entire screen of the input image, and the correction amount calculating portion compares the average of the feature of the frequency characteristic extracted by the feature extracting portion and a feature of a previously stored reference frequency characteristic and calculates the correction amount that brings the average of the features of the frequency characteristics closer to the feature of the previously stored reference frequency characteristic.