1. An image processing apparatus comprising: a color conversion unit that performs color conversion to convert an original image to a luminance image having a luminance component of the original image as a pixel value and to a chromaticity image having a chromaticity component of the original image as a pixel value; an illumination image generation unit that generates an illumination image having an illumination component of the luminance image as a pixel value from the luminance image; a reflectance image generation unit that generates a reflectance image having a stabilized reflectance component of the luminance image as a pixel value based on the luminance image, the illumination image, change degree information representing a degree of change of the pixel value of the illumination image; a luminance reproduction image generation unit that enhances the reflectance component of the luminance image based on the luminance image and the reflectance image to generate a luminance reproduction image reproduced with being improved visibility of the luminance image; and an inverse color conversion unit that performs conversion inverse to the color conversion performed by the color conversion unit on the luminance reproduction image and the chromaticity image.