US Patent No. 10,944,956

IMAGE CALIBRATION METHOD AND APPARATUS APPLIED TO THREE-DIMENSIONAL CAMERA


Patent No. 10,944,956
Issue Date March 09, 2021
Title Image Calibration Method And Apparatus Applied To Three-dimensional Camera
Inventorship Yupeng Jian, Guangdong (CN)
Assignee AUTEL ROBOTICS CO., LTD., Guangdong (CN)

Claim of US Patent No. 10,944,956

1. An image calibration method applied to a three-dimensional camera, wherein the method comprises:photographing, by an image calibration apparatus, a to-be-tested object by using the three-dimensional camera, obtaining an image of the to-be-tested object in a photosensitive area of the three-dimensional camera, and determining a pixel point corresponding to the to-be-tested object in the photosensitive area according to the image of the to-be-tested object;
obtaining, by the image calibration apparatus, for the pixel point corresponding to the to-be-tested object, depth information corresponding to the pixel point, the depth information indicating a distance between the to-be-tested object and the pixel point; and
obtaining, by the image calibration apparatus a measurement deviation value corresponding to the pixel point from a measurement deviation set stored in advance, and correcting the depth information according to the measurement deviation value;
wherein before the obtaining a measurement deviation value corresponding to the pixel point from a measurement deviation set stored in advance, and correcting the depth information according to the measurement deviation value, the method further comprises;
selecting, by the image calibration apparatus, a reference area from the photosensitive area, and calculating an average reference phase difference according to a reference phase difference corresponding to each reference pixel point in the reference area, the reference phase difference indicating a reference distance between a preset reflective surface and the reference pixel point;
calculating by the image calibration apparatus, according to t distance between a target pixel point in the photosensitive area and the reset reflective surface, a target phase difference corresponding to the target pixel point, the target pixel point being any pixel point among all pixel points in the photosensitive area;
comparing, the image calibration apparatus, the obtained target phase difference with the average reference phase difference to obtain a measurement deviation value corresponding to the target pixel point; and
storing, by the image calibration apparatus, the measurement deviation value corresponding to the target pixel point into the measurement deviation set.