US 11,657,537 B2
System and method for calibrating vehicular vision system
Jagmal Singh, Aschaffenburg (DE); Sebastian Pliefke, Sailauf (DE); and Holger Hess, Aschaffenburg (DE)
Assigned to MAGNA ELECTRONICS INC., Auburn Hills, MI (US)
Filed by Magna Electronics Inc., Auburn Hills, MI (US)
Filed on Jan. 4, 2021, as Appl. No. 17/247,967.
Application 17/247,967 is a continuation of application No. 16/658,199, filed on Oct. 21, 2019, granted, now 10,885,669.
Application 16/658,199 is a continuation of application No. 15/467,245, filed on Mar. 23, 2017, granted, now 10,453,217, issued on Oct. 22, 2019.
Claims priority of provisional application 62/312,796, filed on Mar. 24, 2016.
Prior Publication US 2021/0125376 A1, Apr. 29, 2021
Int. Cl. G06T 7/80 (2017.01); H04N 17/00 (2006.01); B60R 1/00 (2022.01)
CPC G06T 7/80 (2017.01) [B60R 1/00 (2013.01); H04N 17/002 (2013.01); B60R 2300/402 (2013.01); G06T 2207/10016 (2013.01); G06T 2207/30252 (2013.01)] 29 Claims
OG exemplary drawing
 
1. A method for calibrating a vehicular vision system, said method comprising:
mounting a camera at a vehicle moving along a vehicle assembly line, the camera, when mounted at the vehicle moving along the vehicle assembly line, having a field of view exterior of the vehicle, wherein the camera comprises a CMOS imaging array having at least one million photosensor elements arranged in columns and rows;
disposing a control at the vehicle moving along the vehicle assembly line, the control comprising an image processor;
capturing frames of image data via the camera as the vehicle moves along an end of line test portion of the vehicle assembly line;
providing to the control frames of image data captured by the camera as the vehicle moves along the end of line test portion of the vehicle assembly line;
processing via the image processor frames of image data captured by the camera as the vehicle moves along the end of line test portion of the vehicle assembly line;
determining, via processing by the image processor of frames of image data captured by the camera as the vehicle moves along a straight path portion of the end of line test portion of the vehicle assembly line, ground features adjacent to the vehicle assembly line;
as the vehicle moves along the straight path portion of the end of line test portion of the vehicle assembly line, tracking using optical flow the determined ground features over two or more frames of image data captured by the camera;
determining misalignment of the camera at the vehicle via tracking the determined ground features as the vehicle moves along the straight path portion of the end of line test portion of the vehicle assembly line; and
responsive to determination of misalignment of the camera at the vehicle, calibrating the vehicular vision system to accommodate the determined misalignment of the camera at the vehicle by using an assumption that the determined ground features lie in a plane parallel to a planar portion of a ground surface adjacent the straight path portion of the end of line test portion of the vehicle assembly line.