April Tag Marker Tracking

Unity Development
1

Give us as much detail as possible regarding the issue you’re experiencing:

I would like to track April Tags with the Magic Leap 2. From the documentation I am using the TrackedMarker, MarkerSpawner, and MarkerTrackerExample scripts to update an objects position based on the positon of the april tag. I have made sure to enable marker tracking permissions and have not had any luck. Is there a sample marker tracker project or further documentation for tracking with april tags?

Unity Editor version:
ML2 OS version:
Unity SDK version: 2022.3.5f1
Host OS: (Windows/MacOS)

Error messages from logs (syntax-highlighting is supported via Markdown):

2

There is an Example on our Developer Portal, there is also an example in the Magic Leap Unity Examples project that can be downloaded from the Magic Leap Hub. You may need to check the logs to see what error you may be getting. Magic Sure you are using the OpenXR implementation of the Marker Tracking API.

3

Hello, I have problems with AprilTag detection as well. Well, it doesn’t get detected :face_with_tongue:

Unity 2022.3.17f1 (but also tried on Unity 6000.1)
SDK 2.6.0-pre.R15
Windows

I have a script perfectly functioning with QR codes, but failing with AprilTag (same script). No error logs. I basically create both detectors in the script:

    public AprilTagType AprilType = AprilTagType.Dictionary_25H9;

    public MarkerDetectorProfile DetectorProfile = MarkerDetectorProfile.Accuracy;

    [...]

    // Create the Marker Detector Settings
    _detectorSettings = new MarkerDetectorSettings();

    _detectorSettings.AprilTagSettings.EstimateAprilTagLength = true;
    _detectorSettings.AprilTagSettings.AprilTagType = AprilType;
    _detectorSettings.MarkerDetectorProfile = DetectorProfile;

    // Create April Detector
    _markerFeature.CreateMarkerDetector(_detectorSettings);
    
    // Create QRCode Detector
    _detectorSettings.QRSettings.EstimateQRLength = true;
    _detectorSettings.MarkerType = MarkerType.QR;
    _markerFeature.CreateMarkerDetector(_detectorSettings);

And yeah the QR gets detected instantly, the AprilTag never. Any idea why that would happen ?

PS: when I print “_markerFeature.MarkerDetectors[i].Settings.MarkerType.ToString()” for the apriltag detector, it prints “Arcuo”, instead of what I would expect: AprilTag… :thinking: And this detector never has a “ready” status (contrary to the QR one).

Also note that the MarkerUnderstandingSample only illustrates a QR code example.

Thanks a lot,
Arnaud