| 摘要 |
PURPOSE: To detect the centroid of a calibration pattern in input image with higher accuracy than the resolution of pixels by picking up the image of the calibration pattern to be used for camera calibration with an image pickup means. CONSTITUTION: A circular pattern, whose density is breadthwise changed from an outer periphery toward the center, is prepared as the calibration pattern, and a straight line to pass through plural positions included in the circular pattern in the input image in the direction of density gradient is calculated for every position. Then, a point, for which the total sum of distances to the respective straight lines is minimum, is defined as the centroid of the circular pattern. |
