Question Loading a Large XR Image Reference Library at runtime

Hello,

We are developing an AR application for which we fetch markers from a web server at runtime.
We populate our XRReferenceImagesLibrary with the ScheduleAddImageWithValidationJob function, that seems to work fine, except :

- The loading time :

• it takes around 1 minute on iOS to load 71 markers.
• it's faster on Android.

- The tracking stability is not satisfying :

• it's actually more stable with ARCore than ARKit, which is unusual.
• the more markers we add, the less stable it is.
• between each marker import, i wait for 4 frames, based on some recommandation from github.

Is there a way to speed up things and improve stability ?

We cannot control that markers delivered by the online API will pass the import successfully for tracking, can this impact the stability for other markers ? (AR_ERROR_IMAGE_INSUFFICIENT_QUALITY)

Apple seems to say we can load hundreds (thousands?) markers without any issue.

Perhaps we are doing something the wrong way, or reaching some limitation with ARFoundation ?

Guillaume

Unity 2020.3.20f1 / ARFoundation 4.1.7

 

To speed up load time, you can create the image library and load it at runtime as an asset bundle.
https://docs.unity3d.com/Packages/c...-reference-image-libraries-with-asset-bundles

Rebuilding the image library at runtime requires time and CPU overhead.

For tracking, ARCore provides recommended practices as documented here:
https://developers.google.com/ar/develop/unity-arf/augmented-images#best_practices

and ARKit recommends "For best results, limit your detection image count to no more than around 100." as documented here:
https://developer.apple.com/documen...2941063-detectionimages?language=objc#3924193