Method and apparatus for automatic intrinsic camera calibration using images of a planar calibration pattern
AssigneeSecond Spectrum, Inc.
InventorsCharles Xavier Quentin Dubout, Horesh Beny Ben Shitrit
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Abstract
The present disclosure relates to a high precision method, model, and apparatus for calibrating the intrinsic camera parameter values of one or more intrinsic parameters of a camera. The intrinsic parameters include focal lengths, skew, optical center, and radial distortion coefficients. The practical implementation of the solution consists of a camera capturing several images of a planar calibration pattern from different viewpoints, and a computer implemented processing pipeline. The solution does not require additional human input and is robust to misdetection of the calibration pattern in some of the images.
Claims20
A method comprising:
- detecting, by a computing unit, a plurality of calibration features in each of a plurality of images;
- generating for each of the plurality of images a corresponding lattice graph based on the plurality of calibration features, the generating referencing a global planar coordinate system having an arbitrary origin;
- selecting with the computing unit one or more image capture parameters from a plurality of image capture parameters associated with capturing the plurality of images, the selecting based on a robust estimator of a reprojection error over the plurality of images;
- and
- calibrating the plurality of image capture parameters based on one or more of the one or more selected image capture parameters and two or more of the calibration features detected in two or more of the plurality of images and the corresponding lattice graphs.
A computing system comprising:
- a processor;
- a computer memory in communication with the processor the computer memory storing a plurality of digital images comprising a plurality of image capture calibration features, a plurality of image capture parameter data values, a plurality of lattice graphs, each lattice graph corresponding to one of the plurality of digital images and having nodes that correspond to a portion of the plurality of image capture calibration features, the plurality of lattice graphs further referencing a global planar coordinate system having an arbitrary origin;
- an image capture parameter selection facility executing on the processor and selecting one or more of the plurality of image capture parameter data values from the computer memory based on an estimate of a reprojection error over the plurality of digital images;
- and
- a calibration facility executing on the processor and calibrating the plurality of image capture parameter data values based on one or more of the selected image capture parameter data values and two or more of the plurality of image capture calibration features in two or more of the plurality of digital images and the corresponding lattice graphs.
Dependencies are inferred from the claim text.