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US 12,307,719 B2Granted
Calibration scale, calibration method and apparatus, and detection method and apparatus
AssigneeContemporary Amperex Technology (Hong Kong) Limited
InventorsGuan Chen, Fei Chen, Guannan Jiang
Life of this patent
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Abstract
A calibration scale includes a scale body and at least two calibration pattern subsets arranged on the scale body along a first direction. The at least two calibration pattern subsets include a plurality of first calibration blocks arranged at spacings along the first direction and staggered along a second direction. Projections of the plurality of first calibration blocks in each calibration pattern subset along the first direction have a first overlapping area. Projections of at least two first overlapping areas along the first direction have a second overlapping area.
Claims15
A camera calibration method for image splicing, comprising
- providing a calibration scale comprising a scale body and a calibration pattern arranged on the scale body, wherein:
- the calibration pattern comprises at least two calibration pattern subsets arranged along a first direction of the scale body, and the at least two calibration pattern subsets comprise a plurality of first calibration blocks arranged at spacings along the first direction and staggered along a second direction of the scale body;
- for each calibration pattern subset, projections of the plurality of first calibration blocks along the first direction have a first overlapping area, and a length of the first overlapping area along the second direction is less than or equal to a first preset threshold;
- and
- projections of at least two first overlapping areas along the first direction have a second overlapping area;
- arranging the calibration scale on a surface of a target object;
- and
- for each of at least two cameras, determining a scan path of the camera based on at least one calibration pattern subset on the calibration scale, comprising:
- adjusting a location of the camera to scan the calibration pattern subset;
- adjusting a scan trajectory of the camera so that the camera sequentially scans all the first calibration blocks in the calibration pattern subset;
- and
- determining, as the scan path, a scan trajectory obtained when projections of both a scan trajectory of the camera and a scan trajectory of an adjacent camera along the first direction completely fall within a second overlapping area.
9 more elements
A film roll detection method, comprising:
- providing a calibration scale comprising a scale body and a calibration pattern arranged on the scale body, wherein:
- the calibration pattern comprises at least two calibration pattern subsets arranged along a first direction of the scale body, and the at least two calibration pattern subsets comprise a plurality of first calibration blocks arranged at spacings along the first direction and staggered along a second direction of the scale body;
- for each calibration pattern subset, projections of the plurality of first calibration blocks along the first direction have a first overlapping area, and a length of the first overlapping area along the second direction is less than or equal to a first preset threshold;
- and
- projections of at least two first overlapping areas along the first direction have a second overlapping area;
- arranging the calibration scale in a surface area of a roller or a film roll wound around the roller;
- providing at least two cameras, and calibrating the at least two cameras based on the calibration scale to obtain a scan path of the at least two cameras and a complete calibrated image, comprising:
- adjusting the locations of the at least two cameras based on the at least two calibration pattern subsets, so that fields of view of the at least two cameras completely cover the at least two calibration pattern subsets;
- adjusting respective scan trajectories of the at least two cameras based on a respective one of the at least two calibration pattern subsets;
- and
- determining, as the scan path, a straight line obtained when projections of the respective scan trajectories along a first direction completely fall within the second overlapping area;
- obtaining at least two sub-images of different areas of the film roll using the at least two calibrated cameras respectively, and splicing the at least two sub-images to obtain a panoramic image of the film roll;
- and
- calculating a target parameter based on the complete calibrated image and the panoramic image.
11 more elements
Dependencies are inferred from the claim text.