DEVICE AND METHOD FOR CALCULATING REFERENCE POINT OF TARGET FOR PHOTOGRAMMETRY, AND RECORDING MEDIUM STORED WITH PROGRAM FOR CALCULATING REFERENCE POINT OF TARGET FOR PHOTOGRAMMETRY

摘要

PROBLEM TO BE SOLVED: To automatically calculate a reference point of a target for photogrammetry in photogrammetry. ;SOLUTION: This reference point calculating method selects a three-point line and a four- point line having high brightness on the same straight line within a photographing image to check whether gravity centers of groups corresponding to respective end points are coincident or not in a step S1056. When coincident, coordinates of the gravity center of the group corresponding to the end points on the side contrary to the end points consistent with the end points of the three-point line out of the groups constituting the four-point lines are stored into a variable A1 in a step S1058, coordinates of the gravity centers of the groups corresponding to the end points consistent in the three-point lines and the four-point lines are stored into a variable A2, and coordinates of the gravity center of the groups corresponding to the end points on the side contrary to the end points consistent with the end points of the four-point line out of the the groups constituting the three-point lines are stored into a variable A3. Whether an anti-clockwise angle which a vector from the A2 to the A3 forms with respect to a vector from the A2 to the A1 is within a prescribed range or not is checked in a step S1060, and the four-point line and the three-point line are determined as a reference point and an auxiliary point, when within the prescribed range.;COPYRIGHT: (C)2000,JPO