Integrated three-dimensional shape and reflection properties measurement system

Abstract

Creating accurate three-dimensional (3D) digitalized models of cultural heritage objects requires that information about surface geometry be integrated with measurements of other material properties like color and reflectance. Up until now, these measurements have been performed in laboratories using manually integrated (subjective) data analyses. We describe an out-of-laboratory bidirectional reflectance distribution function (BRDF) and 3D shape measurement system that implements shape and BRDF measurement in a single setup with BRDF uncertainty evaluation. The setup aligns spatial data with the angular reflectance distribution, yielding a better estimation of the surface's reflective properties by integrating these two modality measurements into one setup using a single detector. This approach provides a better picture of an object's intrinsic material features, which in turn produces a higher-quality digitalized model reconstruction. Furthermore, this system simplifies the data processing by combining structured light projection and photometric stereo. The results of our method of data analysis describe the diffusive and specular attributes corresponding to every measured geometric point and can be used to render intricate 3D models in an arbitrarily illuminated scene.

The Time Effectiveness of Three-Dimensional Telediagnostic Postural Screening of Back Curvatures and Scoliosis

“…32,33 The 3D measurement module is an optical full-field 3D scanner based on the structured light illumination method. [34][35][36] During the measurement process the subject stands still inside a calibrated measurement volume while a series of images is projected onto his or her body surface. The shape of the back of the trunk surface is calculated based on the deformation of the raster.…”

Integrated digitization method for cultural heritage objects

“…Usually their parameters are calculated from a set of images registered with different illumination and observation directions [16]. In the presented setup we use a grid of illuminators which uniformly emit light from several directions [17]. The measurement data serve for calculating coefficients for the Phong model, which is widely used in computer graphics [18].…”

A Variational Study on BRDF Reconstruction in a Structured Light Scanner

“…Krzesłowski et al [12] present a structured light scanner with added LED sources for integrated acquisition of BRDF and surface geometry. However, they fit their sampled BRDF data to the Blinn-Phong model [2,22], which only provides a good BRDF fit for a limited range of materials [19].…”