A mixing ratio database stores information regarding a mixing ratio of plural materials for producing a color corresponding different color chart IDs. A plurality of pieces of color chart spectral information under determination illumination light are calculated using a plurality of pieces of spectral information of spectral reflection factors contained in a color chart and spectral information of the determination illumination light which is information of illumination light used for color chart determination. One of the calculated plural pieces of color chart spectral information which most closely matches spectral information of a subject is determined. A color chart ID which identifies the determined piece of color chart spectral information is output, and information of a mixing amount of each of the plurality of materials for the output color chart ID is also output based on the information stored in the mixing ratio database.