Technical validation of the Di3D stereophotogrammetry surface imaging system
Accepted 24 September 2007. published online 05 November 2007.
Abstract
The purpose of this work was to assess the technical performance of a three-dimensional surface imaging system for geometric accuracy and maximum field of view. The system was designed for stereophotogrammetry capture of digital images from three-dimensional surfaces of the head, face, and neck. A mannequin head was prepared for imaging by adding texture in the form of red paint, and facial landmarks as black ink dots. The mannequin was imaged at the manufacturer's recommended settings for human studies. Colour-coded surface difference images among repeated exposures were computed. We compared measurements of physical linear distance with digital measurements. The three-dimensional stereophotogrammetry system had a mean error in the three-dimensional surfaces of 0.057mm, a repeatability error (variance) of 0.0016mm, a mean error of 0.6mm in linear measurements compared with manual measurements, and a field of view of 170° horizontally and 102° vertically.
aHealth and Rehabilitation Sciences Research Institute, University Of Ulster, Shore Road, Newtownabbey BT37 0QB, N. Ireland, United Kingdom
b3D Craniofacial Image Research Laboratory, University of Copenhagen, Copenhagen University Hospital and the Technical University of Denmark, School of Dentistry, Nørre Alle 20, DK-2200 Copenhagen N., Denmark
cSchool of Electrical and Mechanical Engineering, University of Ulster, Shore Road, Newtownabbey BT37 0QB, United Kingdom
dSchool of Creative Arts, University of Ulster, Londonderry BT48 7JL, United Kingdom
Corresponding author at: Room 1B113, Health and Rehabilitation Sciences Research Institute, University Of Ulster, Shore Road, Newtownabbey BT37 0QB, Northern Ireland, United Kingdom. Tel.: +44 2890368440; fax: +44 2890368068.
ABSTRACT