wrong pattern of markers in dict 4x4_50 with IDs: 9, 12, 19

[aedawid]

The markers with IDs 9, 12, and 19 from the ArUco dictionary 4x4_50 are all lacking the central black square in the patterns. It makes them undetectable with the Find-GCP tool (regardless of the version of the OpenCV library).

[smathermather]

Ah, that explains what I'm seeing.

./gcp_find.py ../gcp_aruco_generator/wat.png | awk '{printf("%02d\n", $4)}' | sort | uniq
duplicate markers on image ../gcp_aruco_generator/wat.png
marker ids: [0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 13, 14, 15, 16, 17, 18, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 45, 46, 48, 49, 49]
Finished in 0.05814660500072932 seconds
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Looks like also 43, 44, 47 are undetectable.

Edit: looks like 4x4_100 similarly has issues with some:

./gcp_find.py ../gcp_aruco_generator/4x4_100.png | awk '{printf("%02d\n", $4)}' | sort | uniq | wc -l
duplicate markers on image ../gcp_aruco_generator/4x4_100.png
marker ids: [0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 13, 14, 15, 16, 17, 18, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 49, 50, 51, 52, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 89, 90, 91, 92, 93, 94, 95, 96, 98, 99]
Finished in 0.0720646490008221 seconds
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