# preliminary:imageAnchoring:referenceImage The characteristics of an image the runtime should scan for in order to attach a prim. ## Discussion An asset assigns this property a prim with type `Preliminary_ReferenceImage`. The runtime searches for an image described by this property in the physical environment. If the runtime finds a match, it places a prim at the image’s real-world location. When a runtime places a prim in the physical environment, the prim’s children also attach to that location. The runtime employs the information contained in this property only when [preliminary:anchoring:type](/documentation/USD/preliminary-anchoring-type) is `image`. ### Declaration ```other rel preliminary:imageAnchoring:referenceImage ``` ### Anchor a cube to an image The following example demonstrates how an asset defines a reference image (`ImageReference`) that the runtime should look for in the physical environment. The asset includes a cube that assigns an [Preliminary_ReferenceImage](/documentation/USD/preliminary-referenceimage) to its [preliminary:imageAnchoring:referenceImage](/documentation/USD/preliminary-imageanchoring-referenceimage) property, instructing the runtime to anchor it to a real-world object that matches the image criteria. ```other def Cube "ImageAnchoredCube" ( prepend apiSchemas = [ "Preliminary_AnchoringAPI" ] ) { uniform token preliminary:anchoring:type = "image" rel preliminary:imageAnchoring:referenceImage = ... def Preliminary_ReferenceImage "ImageReference" { uniform asset image = @image.png@ uniform double physicalWidth = 0.12 } } ``` --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)