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perfanalytics / pose2sim

Markerless kinematics with any cameras — From 2D Pose estimation to 3D OpenSim motion
https://perfanalytics.github.io/pose2sim/
BSD 3-Clause "New" or "Revised" License
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Does calibration with a board put the Y in the wrong direction #118

Open ANaaim opened 4 months ago

ANaaim commented 4 months ago

Other question :

When using board calibration, the data are ... upside down. Is it the expected behavior ?

image

Sorry for all the question, I am finishing a V1 for my tool-box ^^ so... a lot of use case

davidpagnon commented 4 months ago

Definitely not expected, but it can happen depending on the pattern of the checkerboard. I have not been able to check, but I think the X axis goes from the black corner to the other black corner, and the Y axis from the black corner to the white one. So if you have something like in the picture below, you end up with a Z axis going underground.

image

The solution to this would be to print another checkerboard, mirrored from this one. I'm not a 100 percent sure of this so I'd be grateful if you can confirm!

(Note that in any case, you need to have a number of rows different from the number of lines, otherwise it will not be rotationally invariant and axes will be attributed randomly).

ANaaim commented 4 months ago

Ok 👍 I Will investigate :)