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To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
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There is a reference to the original bug report and related work
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The feature is well documented and sample code can be built with the project CMake

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AleksandrPanov commentedJan 15, 2023•
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works with choriginal.jpg:

tutorial_camera_charuco.yml.txt

args:
-w=5 -h=7 -sl=0.04 -ml=0.02 -d=10 -v=choriginal.jpg

result:

To correctly works withmatchImagePoints need merge PR#23138

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January 15, 2023 23:54

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Jan 15, 2023

fix charuco matchImagePoints#23138

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Jan 15, 2023

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January 16, 2023 09:03

AleksandrPanov force-pushed theadd_py_charuco_sample branch 2 times, most recently from8d1006b to3a5109dCompare

January 16, 2023 18:25

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Jan 16, 2023

Charuco marker pose estimation -> Z-axis in wrong directionopencv/opencv-python#755

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satpalsr commentedJan 18, 2023•
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Hey@AleksandrPanov , can you share how you generated charuco board? Specially want to fit on A4 paper size.

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AleksandrPanov commentedJan 18, 2023•
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Hey@satpalsr, you can use code from this sample:

import cv2 as cvfrom cv2 import arucoprint(cv.__version__)"setup"arucoDict = aruco.getPredefinedDictionary(aruco.DICT_6X6_250)"create the charuco board"calibration_board = aruco.CharucoBoard((5, 7), squareLength=0.072, markerLength=0.062, dictionary=arucoDict)board_image = calibration_board.generateImage((500, 700))cv.imwrite("sample_board.png", board_image)

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Jan 18, 2023

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modules/objdetect/samples/python/detect_board_charuco.py OutdatedShow resolvedHide resolved

AleksandrPanov force-pushed theadd_py_charuco_sample branch 2 times, most recently fromf80907a to0a649e5Compare

January 19, 2023 16:50

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asmorkalov commentedJan 20, 2023

Current version of sample fails with exception, when Charuco board is shown to camera:

[ WARN:0@1.571] global cap_gstreamer.cpp:1728 open OpenCV | GStreamer warning: Cannot query video position: status=0, value=-1, duration=-1Traceback (most recent call last):  File "./aruco_detect_board_charuco.py", line 110, in <module>    main()  File "./aruco_detect_board_charuco.py", line 95, in main    if len(charuco_ids) > 0:TypeError: object of type 'NoneType' has no len()

AleksandrPanov force-pushed theadd_py_charuco_sample branch from0a649e5 toe16d7e4Compare

January 20, 2023 14:44

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AleksandrPanov commentedJan 20, 2023

addNoneType checks

Now sample must works in all cases:
part charuco corners:

full charuco corners:

and also works without charuco corners

(Uses PR#23138)

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January 20, 2023 15:15

AleksandrPanov force-pushed theadd_py_charuco_sample branch frome16d7e4 to5002478Compare

January 20, 2023 15:23

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January 20, 2023 15:24

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AleksandrPanov commentedJan 20, 2023•
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I check sample with camera and add new condition to correct work with solvePnP():
if len(cam_matrix) > 0 and len(charuco_ids) >= 4:

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satpalsr commentedJan 21, 2023

Also addif len(obj_points) >= 6:

Otherwise I get

    flag, rvec, tvec = cv.solvePnP(obj_points, img_points, cam_matrix, dist_coefficients)cv2.error: OpenCV(4.7.0) /io/opencv/modules/calib3d/src/calibration.cpp:1173: error: (-2:Unspecified error) in function 'void cvFindExtrinsicCameraParams2(const CvMat*, const CvMat*, const CvMat*, const CvMat*, CvMat*, CvMat*, int)'> DLT algorithm needs at least 6 points for pose estimation from 3D-2D point correspondences. (expected: 'count >= 6'), where>     'count' is 4> must be greater than or equal to>     '6' is 6