1. An image processing apparatus comprising: a specific image detection unit detecting an area including at least a part of a specific image in an input image; a representative color calculation unit calculating a representative color of the specific image on the basis of pixels belonging to the area detected by the specific image detection unit; a first correction curve acquisition unit acquiring a first correction curve for gradation correction on the basis of brightness of the representative color; a second correction curve acquisition unit correcting the representative color by the first correction curve and acquiring a second correction curve for gradation correction for every element color on the basis of the gradation value for every element color constituting the representative color after correction; a first correction unit correcting the gradation values of pixels, which belong to a color gamut defining a dark portion, from among pixels constituting the input image by using the first correction curve; and a second correction unit correcting the gradation value for every element color in each pixel constituting the input image by using the second correction curve.