6x6_50
6x6_50 holds 50 markers of
6×6 bits. In OpenCV it is
cv2.aruco.DICT_6X6_50.
The numbers
| OpenCV name | cv2.aruco.DICT_6X6_50 |
| Bits in a marker | 6 × 6 = 36 |
| Markers available | 50, with IDs 0 to 49 |
| Printed width | 8 cells, border included |
| Bits the decoder repairs | 6 |
| Cell size on a 100 mm marker | 12.5 mm |
| Pixels wanted in the image | 96 (floor 32) |
| Range for a 100 mm marker | about 1.7 m |
Range assumes a camera 1920 px wide, 60 degree horizontal field of view, which is a focal length of about 1663 pixels, and a marker seen straight on.
When to use it
Six bit markers are the usual default. They carry enough redundancy to shrug off a damaged or partly shadowed cell, at a modest cost in range. With 50 markers this suits a single board or a small set of tagged objects.