US 12,361,572 B2
System and method of automatic image view alignment for camera-based road condition detection on a vehicle
Qingrong Zhao, Warren, MI (US); Farui Peng, Sterling Heights, MI (US); and Bakhtiar B. Litkouhi, Washington, MI (US)
Assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed by GM Global Technology Operations LLC, Detroit, MI (US)
Filed on Jul. 28, 2022, as Appl. No. 17/815,760.
Prior Publication US 2024/0046491 A1, Feb. 8, 2024
Int. Cl. G06T 7/33 (2017.01); G06T 5/80 (2024.01); G06V 20/56 (2022.01)
CPC G06T 7/337 (2017.01) [G06V 20/588 (2022.01); G06T 2207/30252 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method of image alignment for an advanced driver assistance system (ADAS) equipped vehicle, comprising:
capturing, by an optical camera having a fisheye lens, a subject fisheye image of an external field of view surrounding the vehicle;
transforming, by a controller, the subject fisheye image into a subject rectilinear image, wherein the subject rectilinear image includes a subject feature point;
retrieving a reference rectilinear image of an external field of view surrounding a reference vehicle, wherein the reference rectilinear image includes a reference feature point;
determining a distance (d) between the subject feature point in the subject rectilinear image and the reference feature point in the reference rectilinear image, wherein the subject rectilinear image is compared side-by-side to the reference rectilinear image;
determining whether the distance (d) is greater than a predetermined threshold;
calculating a pitch angle custom character to align the subject feature point with the reference feature point in response to the determined distance (d) is greater than the predetermined threshold; and
generating an aligned subject rectilinear image by applying a rectification transformation on the subject fisheye image by relocating a center of projection of the subject fisheye image by the pitch angle custom character.