CROSSING POINT DETECTOR, CAMERA CALIBRATION SYSTEM, CROSSING POINT DETECTION METHOD, CAMERA CALIBRATION METHOD, AND RECORDING MEDIUM

摘要

A crossing point detector includes a memory and a crossing point detection unit that reads out a square image from a captured image in the memory, and detects a crossing point of two boundary lines in a checker pattern depicted in the square image. The crossing point detection unit decides multiple parameters of a numerical model, the parameters optimizing an evaluation value based on a difference between corresponding pixel values represented by the numerical model and the square image, respectively, and computes the position of a crossing point of two straight lines expressed by the decided multiple parameters to thereby detect the crossing point with subpixel precision. The numerical model is a model that simulates a pixel integration effect when imaging a step edge by assigning pixel values to respective regions inside a pixel divided by a straight line, and deciding a pixel value of the overall pixel.