Image data representing an image are obtained. A quadrangular area, which is defined by a quadrangle including a group of pixels with a first color, is specified. The first color corresponds to a color of an outline of a hole image in the image. A hole orientation is specified based on positions of the group of pixels with respect to the quadrangular area. The hole orientation represents a direction that the outline of the hole image occupies. When the hole orientation is specified, a candidate area is specified by extending the quadrangular area in an extension direction. The extension direction corresponds to a direction opposite to the hole orientation and extending along one of sides of the quadrangular area.