Evaluating snapping-to-photos virtual travel interfaces for 3D reconstructed visual reality

Navigating through a virtual, 3D reconstructed scene has recently become very important in many applications. A popular approach is to virtually travel to the photos used in reconstructing the scene; such an approach may be generally termed a "snapping-to-photos" virtual travel interface. While previous work has either used fully constrained interfaces (always at the photos) or minimally constrained interfaces (free-flight navigation), in this paper we introduce new snapping-to-photos interfaces that lie in between these two extremes. Our snapping-to-photos interfaces snap the view to a photo in 3D based on viewpoint similarity and optionally the user's mouse cursor or finger-tap position. Experimental results, with both indoor and outdoor scene reconstructions, found that our snapping-to-photos interfaces are preferred over the baseline fully constrained-to-photos interface, that there exist differences between indoor and outdoor scenes, and that users preferred and were able to reach target photos better with click-to-snap point-of-interest snapping compared to automatic point-of-view snapping.