FIELD: calibration of a camera.
SUBSTANCE: to determine the installation angles of the camera relative to the longitudinal axis of the car, a sequence of frames received by the camera is recorded while the car is moving during the calibration process. A matrix M is formed from them; information is accumulated in its cells regarding the points of intersection of the trajectories of singular points in the vicinity of the vanishing point. The obtained trajectories are also periodically checked for length and straightness; short ones and those strongly deviating from a straight trajectory are not taken into consideration. Further, the remaining trajectories are approximated by straight lines, the pixel coordinates of the points of their pairwise intersection are calculated, and the camera installation angles, such as the pitch angle and the yaw angle, are determined from the pixel coordinates of the average vanishing point. The adaptive median filtering procedure is applied to the pixel coordinates of the points of pairwise intersections of the trajectories to exclude the intersection points lying outside the vicinity of the vanishing point from the averaging procedure, and the distortion correction procedure is applied to the estimated coordinates of the singular points.
EFFECT: reduced calibration error by reducing the error in estimating the pixel coordinates of the vanishing point.
2 cl, 2 dwg 1 tbl
