The data interpolation section 6 includes: a direction data calculation section 61 for calculating a plurality of direction data, each of the plurality of direction date indicating a directional amount along a plurality of directions including at least one of an upper right direction and a lower right direction within the vicinity of a target pixel; a direction detection section 62 for detecting at least one direction of the edge within the vicinity of the target pixel by using the plurality of direction data calculated by the direction data calculation section 61; a direction color signal calculation section 63 for calculating at least one color signal corresponding to the at least one direction detected by the direction detection section 62; and a target pixel color signal calculation section 64 for calculating a color signal for the target pixel by using the at least one color signal calculated by the direction color signal calculating section 63.