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ar_track_alvar does not recognize tags

asked 2016-11-24 03:34:03 -0600

Anis
253 ●22 ●26 ●34

updated 2016-11-25 08:09:24 -0600

Hello

I have used the ar_track_alvar ROS package to recognise AR Tags. The problem is that it only recognizes tag zero, and for all other tags, it gives wrong and very large ID and is not consistent. Sometimes it also gives wrong values for tag zero, but most often it is correct.

What could be the problem??

Thank you Anis

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answered 2016-11-26 06:57:22 -0600

Boris

3060 ●32 ●57 ●83 http://people.idsia.ch/~gromov

It could be an issue with the camera parameters. Make sure it is calibrated and all the settings are correct and appropriate for your environment, e.g. check gain and exposure (if your camera supports these).

I usually see this issue (confusion of marker ID) when the marker is either too far away or the image is too dark/bright.

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Asked: 2016-11-24 03:34:03 -0600

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Last updated: Nov 26 '16

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ar_track_alvar does not recognize tags