aruco_calibrator.py

import os
import numpy as np
import cv2

# ------------------------------
# ENTER YOUR REQUIREMENTS HERE:
ARUCO_DICT = cv2.aruco.DICT_4X4_250
SQUARES_VERTICALLY = 7
SQUARES_HORIZONTALLY = 5
SQUARE_LENGTH = 0.03
MARKER_LENGTH = 0.015
# ...
PATH_TO_YOUR_IMAGES = 'calib'


# ------------------------------

def calibrate_and_save_parameters():
    # Define the aruco dictionary and charuco board
    dictionary = cv2.aruco.getPredefinedDictionary(ARUCO_DICT)
    board = cv2.aruco.CharucoBoard((SQUARES_VERTICALLY, SQUARES_HORIZONTALLY),
                                   SQUARE_LENGTH, MARKER_LENGTH, dictionary)
    params = cv2.aruco.DetectorParameters()

    # Load PNG images from folder
    image_files = [os.path.join(PATH_TO_YOUR_IMAGES, f) for f in
                   os.listdir(PATH_TO_YOUR_IMAGES) if f.endswith(".jpg")]
    image_files.sort()  # Ensure files are in order

    all_charuco_corners = []
    all_charuco_ids = []

    for image_file in image_files:
        image = cv2.imread(image_file)
        image_copy = image.copy()
        marker_corners, marker_ids, _ = cv2.aruco.detectMarkers(image,
                                                                dictionary,
                                                                parameters=params)

        # If at least one marker is detected
        if marker_ids is not None and len(marker_ids) > 0:
            cv2.aruco.drawDetectedMarkers(image_copy, marker_corners,
                                          marker_ids)
            charuco_retval, charuco_corners, charuco_ids = \
                cv2.aruco.interpolateCornersCharuco(
                marker_corners, marker_ids, image, board)
            if charuco_retval:
                all_charuco_corners.append(charuco_corners)
                all_charuco_ids.append(charuco_ids)

    # Calibrate camera
    retval, camera_matrix, dist_coeffs, rvecs, tvecs = \
        cv2.aruco.calibrateCameraCharuco(
        all_charuco_corners, all_charuco_ids, board, image.shape[:2], None,
        None)

    # Save calibration data
    np.save('camera_matrix.npy', camera_matrix)
    np.save('dist_coeffs.npy', dist_coeffs)

    cv2.destroyAllWindows()


calibrate_and_save_parameters()