US 12,354,293 B2
Calibration method for distance measurement device, distance measurement device, and storage medium
Takashi Shiozawa, Tokyo (JP)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Jun. 13, 2023, as Appl. No. 18/333,582.
Claims priority of application No. 2022-113984 (JP), filed on Jul. 15, 2022.
Prior Publication US 2024/0020865 A1, Jan. 18, 2024
Int. Cl. G06T 7/55 (2017.01); G06T 5/50 (2006.01); G06T 5/80 (2024.01); G06T 7/80 (2017.01)
CPC G06T 7/55 (2017.01) [G06T 5/80 (2024.01); G06T 7/80 (2017.01); G06T 2207/10028 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A calibration method for a distance measurement device that is mounted inside a moving body, images outside of the moving body through a transparent body, and calculates a distance to an object by using disparity of images captured from at least two points of view, the method comprising:
a first process of capturing a first-image-for-calibration and a second-image-for-calibration at different distances between a first-object-for-calibration and the distance measurement device that is not installed inside the moving body without intervention of the transparent body and calculating correction information having a first correction value and a second correction value, for converting disparity information calculated from image information of each of the first-image-for-calibration and the second-image-for-calibration into distance information; and
a second process of capturing a third-image-for-calibration from a second-object-for-calibration that is located at least at a distance via the transparent body and modifying the correction information calculated in the first process on the basis of image information of at least the captured third-image-for-calibration installing the distance measurement device inside the moving body;
wherein the distance measurement device converts the disparity information into the distance information using a linear function, the first correction value is a first-order coefficient of the linear function, and the second correction value is a zeroth-order coefficient of the linear function.