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Marker (fiducial) tracking without jumping

Hi!

I’m reading markers (“fiducials”) using the fidtrack-node (FiducialTracker). I would like to avoid the jump of the orientation value when a fiducial is removed, rotated and put in again. In my patch the value is stored when a fiducial is removed, but the value jumps to the new value immediately when it is visible for the camera again.

Example:
the fiducial is visible to the camera. It is turned by 20°, then it is removed (not visible anymore). It is turned further by 60° (-> so the whole rotation is now 20°+60°=80°). When I put it back again (fiducial is visible), I want to continue with the value that was visible to the camera before removing (i.e. 20°). Does anybody know a solution for this? Thanks a lot for your support!

see this file:
http://vvvv.org/tiki-download_file.php?fileId=1005IDcheck+map.v4p (11.00 Kb)

helo. your patch is missing a subpatch: IDCheck.v4p

hi, you just need a relative value change, like in this patch:

sorry, the patch was wrong, here is it again. but you have to put in a LinearFilter in cyclic mode or a Mod node somewhere, to avoid jumps when turning form 359 to 0 degree…

relative_value.v4p (9.3 kB)