1. A coordinate calculating apparatus for calculating two object position coordinate points from an image captured by an image capturing apparatus, the two object position coordinate points indicating positions of two predetermined objects whose images to be captured, the positions being on a plane corresponding to the captured image, the apparatus comprising: coordinate detecting means of detecting a position coordinate point of an area satisfying a predetermined condition in the captured image for each area; vector setting means of setting a vector indicating a relative positional relationship between two position coordinate points in the captured image; and coordinate determining means of determining one of the L detected position coordinate points detected by the coordinate detecting means as one of the object position coordinate points, and determining the other object position coordinate point using the one of the detected position coordinate points and the vector.