A coordinate-conversion-parameter determination apparatus includes a marker detector that detects feature points of a marker from each of a first and second images; a three-dimensional position determiner that calculates three-dimensional coordinates of each of the feature points of the marker in a camera coordinate system in which reference is a first place, based on positions of the feature points in the first and second images; and a coordinate-conversion-parameter determiner that calculates a coordinate conversion parameter so that a sum of absolute values of errors between three-dimensional coordinates in a world coordinate system, the three-dimensional coordinates in the world coordinate system being obtained by converting the three-dimensional coordinates of the feature points of the marker in the camera coordinate system by using the coordinate conversion parameter, and three-dimensional coordinates of feature points in the world coordinate system that correspond to the feature points of the marker in real space is minimized.
Coordinate-conversion-parameter determination apparatus, coordinate-conversion-parameter determination method, and non-transitory computer readable recording medium having therein program for coordinate-conversion-parameter determination