TY - JOUR

T1 - Using virtual reality for anatomical landmark annotation in geometric morphometrics

AU - Messer, Dolores

AU - Atchapero, Michael

AU - Jensen, Mark B.

AU - Svendsen, Michelle S.

AU - Galatius, Anders

AU - Olsen, Morten T.

AU - Frisvad, Jeppe R.

AU - Dahl, Vedrana A.

AU - Conradsen, Knut

AU - Dahl, Anders B.

AU - Bærentzen, Andreas

N1 - Publisher Copyright: © 2022 PeerJ Inc.. All rights reserved.

PY - 2022

Y1 - 2022

N2 - To study the shape of objects using geometric morphometrics, landmarks are oftentimes collected digitally from a 3D scanned model. The expert may annotate landmarks using software that visualizes the 3D model on a flat screen, and interaction is achieved with a mouse and a keyboard. However, landmark annotation of a 3D model on a 2D display is a tedious process and potentially introduces error due to the perception and interaction limitations of the flat interface. In addition, digital landmark placement can be more time-consuming than direct annotation on the physical object using a tactile digitizer arm. Since virtual reality (VR) is designed to more closely resemble the real world, we present a VR prototype for annotating landmarks on 3D models. We study the impact of VR on annotation performance by comparing our VR prototype to Stratovan Checkpoint, a commonly used commercial desktop software. We use an experimental setup, where four operators placed six landmarks on six grey seal (Halichoerus grypus) skulls in six trials for both systems. This enables us to investigate multiple sources of measurement error. We analyse both for the configuration and for single landmarks. Our analysis shows that annotation in VR is a promising alternative to desktop annotation. We find that annotation precision is comparable between the two systems, with VR being significantly more precise for one of the landmarks. We do not find evidence that annotation in VR is faster than on the desktop, but it is accurate.

AB - To study the shape of objects using geometric morphometrics, landmarks are oftentimes collected digitally from a 3D scanned model. The expert may annotate landmarks using software that visualizes the 3D model on a flat screen, and interaction is achieved with a mouse and a keyboard. However, landmark annotation of a 3D model on a 2D display is a tedious process and potentially introduces error due to the perception and interaction limitations of the flat interface. In addition, digital landmark placement can be more time-consuming than direct annotation on the physical object using a tactile digitizer arm. Since virtual reality (VR) is designed to more closely resemble the real world, we present a VR prototype for annotating landmarks on 3D models. We study the impact of VR on annotation performance by comparing our VR prototype to Stratovan Checkpoint, a commonly used commercial desktop software. We use an experimental setup, where four operators placed six landmarks on six grey seal (Halichoerus grypus) skulls in six trials for both systems. This enables us to investigate multiple sources of measurement error. We analyse both for the configuration and for single landmarks. Our analysis shows that annotation in VR is a promising alternative to desktop annotation. We find that annotation precision is comparable between the two systems, with VR being significantly more precise for one of the landmarks. We do not find evidence that annotation in VR is faster than on the desktop, but it is accurate.

KW - 3D annotation

KW - Geometric morphometrics

KW - Halichoerus grypus

KW - Measurement error

KW - Stratovan checkpoint

KW - Virtual morphology

KW - Virtual reality

U2 - 10.7717/peerj.12869

DO - 10.7717/peerj.12869

M3 - Journal article

C2 - 35186472

AN - SCOPUS:85124595207

VL - 10

JO - PeerJ

JF - PeerJ

SN - 2167-8359

M1 - e12869

ER -