pupil-labs / apriltags

Python bindings for the apriltags3 library
https://pupil-apriltags.readthedocs.io/en/latest/index.html
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Is the order of the corner detection consistent? #33

Open vshesh opened 3 years ago

vshesh commented 3 years ago

I see in the docs it says that the corners are always returned counter-clockwise around the tag. Is the starting corner always the same corner? Would like to know this so I can detect what angle the tag is at (from a mostly overhead camera).

walchko commented 3 years ago

Not really an answer, but I recently had a similar question. A simple example, I took an example image and color coded the first corner and got this result.

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The corner is always the lower left. A few other examples I have done return the same results, but I have only done examples like this (tags oriented upright on a wall). I have not done anything with the tags rotated in various orientations which would give you an angle (or heading if top down) to prove this works like you are asking.

Maybe someone else has done what you want.