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Vuforia Questions about Image Target local position

March 31, 2021 - 11:35pm #1


I have a problem creating the application, so I am asking a question.

First, when AR Image Target is detected, a floor is installed on Image Target and characters interact on floor.

( In Hierarchy, the floor object is the child object of Image Target, and in Scene, the floor is placed on Image Target. )

The problem here is that floor keeps shaking on top of AR Image Target.

Question 1. I want to create a virtual world at the marker location when I detect the AR marker in reality so that the floor is no longer shaken.

Is there a way to know the location of the AR marker when the actual AR marker is detected by the camera on the device?

Question 2. OnTrackingFound() call from the ITrackableEventHandler occurs. It's called too often, can i help lower the frequency?

please help, thank

Vuforia Questions about Image Target local position

April 28, 2021 - 11:37pm #3


I'm sorry for checking late

Q1. I set the size value used to 1 for convenience when uploading targets to Vuforia Target Manager.

I will test by setting the actual size of the image.

And I will also set up and test Track Device Pose.


Q2. I set the flag to run OnTrackingFound() only once, but I confirmed that it still runs.

I asked a second question to reduce burden because I was testing on an older mobile that supported Vuforia.


Thank you for your answer.

Vuforia Questions about Image Target local position

April 28, 2021 - 1:22am #2


See my answer for your 2 questions:


Q1:Pose jitter exists for all 2D planar targets. The magnitude of the jitter (hardly noticeable to very noticeable) can be impacted by a few factors:

  • Always print the image that was uploaded to the portal to the exact same aspect ratio. Any stretching or altering of the image may cause tracking pose jitter. Some printers default to "stretch to fit", which can change the aspect ratio.
  • Check the size values you are using when uploading Targets to the Vuforia Target Manager. Note there is specific language used in the dialogue box that says Vuforia uses meters as the default unit scale. Incorrect target sizes could affect either our detection/tracking algorithm
  • Image Targets must be flat when in the camera's field of view
  • Not enough lighting upon, and/or spectral reflections occluding the Image Target
  • The entire target image is not in the camera's field of view. As Image Targets extract feature points from the target in real time (on a frame-by-frame basis), the more feature points the better the quality of the tracking experience. In most cases, this can be improved by enabling the Device Tracker (aka Extended Tracking): Unity Editor->Window->Vuforia Configuration->Device Tracker->Track Device Pose (box checked).

For additional tips for optimizing 2D planar targets, please see the following guide:

Q2. My understanding is that OnTrackingFound() is called on recognition and based on the status, if it has a pose or not. Could you please let me know on which VE version are you seeing this and how its affecting your workflow?

Thank you.

Vuforia Engine Support

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