Calibration board and calibration method and system

A calibration method, comprising:

• obtaining a calibration image of a calibration board captured by a camera, wherein the calibration board comprises checkerboard cells arranged on a surface of the calibration board, and at least one dot is arranged in each of the checkerboard cells, and the dots of the checkerboard cells comprise at least a first feature dot and a second feature dot, and a diameter of the first feature dot is greater than a diameter of the second feature dot;
• determining a position of the calibration board in the calibration image, and detecting dots on the calibration board;
• gridding the detected dots based on the checkerboard cells to obtain a first two-dimensional matrix;
• determining types of the detected dots, binarizing the detected dots based on the first two-dimensional matrix according to the types of the detected dots, to obtain a second two-dimensional matrix;
• matching the second two-dimensional matrix with a calibration board number template matrix, to obtain dot-centroid coordinate number information of the second two-dimensional matrix;
• and
• outputting, according to the obtained dot-centroid coordinate number information, corner-point number information corresponding to the checkerboard cells in which the detected dots are located, and calculating calibration data, according to the dot-centroid coordinate number information, the corner-point number information, and a corresponding camera model, by using a calibration algorithm.

A calibration system, comprising a calibration board, a camera, a processor, and a memory, wherein

• the camera is configured to capture a calibration image of the calibration board;
• the calibration board comprises:
• checkerboard cells arranged on a surface of the calibration board, wherein at least one dot is arranged in each of the checkerboard cells, and the dots of the checkerboard cells comprise at least a first feature dot and a second feature dot, and a diameter of the first feature dot is greater than a diameter of the second feature dot;
• and
• the memory is configured to store executable instructions, and the processor is configured to read the executable instructions from the memory to perform operations comprising:
• obtaining the calibration image of the calibration board captured by the camera;
• determining a position of the calibration board in the calibration image, and detecting dots on the calibration board;
• gridding the detected dots based on the checkerboard cells, and obtaining a first two-dimensional matrix;
• determining types of the detected dots, binarizing the detected dots based on the first two-dimensional matrix according to the types of the detected dots to obtain a second two-dimensional matrix;
• matching the second two-dimensional matrix with a calibration board number template matrix to obtain dot-centroid coordinate number information of the second two-dimensional matrix;
• and
• outputting, according to the obtained dot-centroid coordinate number information, corner-point number information corresponding to the checkerboard cells in which the detected dots are located, and calculating calibration data, according to the dot-centroid coordinate number information, the corner-point number information, and a corresponding camera model, by using a calibration algorithm.