Image Tracking

Overview

Image tracking enables devices to recognize specific images on surfaces (such as posters, playing cards, or digital displays). You can use image tracking to locate images in the user's environment and overlay them with virtual content. For example, applications can leverage image tracking to detect specific images and provide users with on-screen experiences like 3D product visualizations.

Requirements

• Requires Play For Dream MR device
• OS version 3.1.0 or higher

Configuring Reference Image Gallery

Creating Image Tracking Library

Create a ToTrackImagesCollectionSO resource under Assets\XR\Resources\

This creates an image tracking library where you can add images for recognition.

Adding Images to Library

1. Import images into the project via Assets > Import New Asset
2. Add images to the reference library:
   • Open ToTrackImagesCollectionSO.asset in the Inspector window
   • Click Add new image to add tracking images
   • Configure image information

Configuring Tracked Images

Configure settings in the Inspector window after adding images:

Property	Description
Image Id	Runtime identifier for detected reference images (string)
Image	Texture2D resource created from reference image file
Size	Physical display size of tracked image (in meters)
Image File Path	Path to reference image

Image Tracking Management

Enable/Disable Image Tracking

// Toggle image tracking functionality
ImageTrackingMgr.instance.SwitchImageTracking(true);

Parameters:

Name	Type	Description
enable	bool	true: Enable tracking false: Disable tracking

Register All Configured Image Templates

ImageTrackingMgr.instance.RegisterTrackImageLibrary();

Register Global Tracking Callback (All Images)

ImageTrackingMgr.instance.RegisterImageTrackingUpdateCallback(OnImageTrackingUpdate);
private void OnImageTrackingUpdate(TrackedImageInfo info){}

Parameters:

Name	Type	Description
callback	Action	Tracking update callback

Unregister Global Callback

ImageTrackingMgr.instance.UnRegisterImageTrackingUpdateCallback(OnImageTrackingUpdate);

Parameters:

Name	Type	Description
callback	Action	Callback to remove

Register Image-Specific Callback

ImageTrackingMgr.instance.RegisterImageTrackingUpdateCallback("targetImage", OnImageTrackingUpdate);
private void OnImageTrackingUpdate(TrackedImageInfo info){}

Parameters:

Name	Type	Description
imageId	string	Target image ID
callback	Action	Tracking callback for this image

Unregister Image-Specific Callback

ImageTrackingMgr.instance.UnRegisterImageTrackingUpdateCallback("targetImage", OnImageTrackingUpdate);

Parameters:

Name	Type	Description
imageId	string	Target image ID
callback	Action	Callback to remove

Unregister Image Template

// Uses Image Id from ToTrackImagesCollectionSO resource
ImageTrackingMgr.instance.UnRegisterImageTemplate("targetImage");

Parameters:

Name	Type	Description
imageId	string	Image ID to unregister

Usage Example

// Enable VST
YVRManager.instance.hmdManager.SetPassthrough(true);

// Register All Configured Image Templates
ImageTrackingMgr.instance.RegisterTrackImageLibrary();

// Register global callback
ImageTrackingMgr.instance.RegisterImageTrackingUpdateCallback(OnImageTracked);

// Register image-specific callback
ImageTrackingMgr.instance.RegisterImageTrackingUpdateCallback("targetImage", OnTargetTracked);

// Enable tracking
ImageTrackingMgr.instance.SwitchImageTracking(true);

void OnImageTracked(TrackedImageInfo info)
{
    Debug.Log($"Tracked image: {info.imageId}");
}

void OnTargetTracked(TrackedImageInfo info)
{
    Debug.Log($"Specific image position: {info.pose.position}");
}