1. An image processing apparatus comprising: a first-image generation unit that generates a first image by performing a visibility enhancement process for enhancing visibility of a subject in an original image, the visibility enhancement process being performed on the original image in a first color space that is a color space not prone to having color values that fall outside a color gamut as a result of conversion of color values of pixels in the original image performed in the visibility enhancement process; a representative chromaticity determination unit that determines a representative chromaticity that represents chromaticities of pixels in a first region that is an entirety or a part of one of the original image and the first image; and a second-image generation unit that generates a second image by performing, in a second color space that is an equivalent color space, a process for adjusting color values of pixels in a second region that is the entirety or the part of the first image to make the representative chromaticity close to a target chromaticity.