1. A three dimensional image processing apparatus, comprising: a storage unit which stores data of a plurality of images having different radiographing directions; a feature point designation unit which designates, with operation by an operator, a respective feature point on at least two selected images selected from said plurality of images; an operation support unit which generates information for supporting the operation of the operator to designate the respective feature points, wherein the operation support unit determines a predictive area in which a feature point on another selected image of the at least two selected images is located, on the basis of a two dimensional position of a feature point designated on at least one selected image of the at least two selected images and a radiographing direction of the another selected image; a three dimensional position calculation unit which calculates a three dimensional position associated with the respective feature points on the basis of (1) a radiographing direction corresponding to the at least two selected images, and (2) two dimensional positions of the designated respective feature points on the at least two selected images; a two dimensional position calculation unit which calculates a two dimensional position of a calculated feature point on an unselected image of said plurality of images on the basis of (1) a radiographing direction corresponding to the unselected image, and (2) the calculated three dimensional position of the respective designated feature points; a feature point extraction unit which extracts an extracted feature point from the unselected image; a positional shift calculation unit which calculates a positional shift of a two dimensional position of the extracted feature point with respect to the calculated two dimensional position of the calculated feature point; a correction unit which corrects a position of the unselected image on the basis of the calculated positional shift; and an image reconstruction unit which reconstructs a three dimensional image on the basis of the at least two selected images and the corrected unselected image.