An extraction unit determines whether, in a display area of a display unit in which content data obtained from an acquisition unit are displayed, there is a character area in which an area occupied by a character has a proportion greater than a predetermined value. Based on color information of the character in an area which is determined to be the character area by the extraction unit, a setting unit sets a target color temperature when the content data is displayed. A converter changes an original color temperature of the content data to the target color temperature, based on the target color temperature set by the setting unit.