Polarimetric BSSRDF Acquisition of Dynamic Faces

TL;DR

This paper introduces a novel polarimetric acquisition system for dynamic human faces that captures detailed appearance, geometry, and biophysical skin parameters, enabling improved rendering and analysis of facial features and skin properties.

Contribution

It is the first system to simultaneously acquire polarimetric, spectral, and biophysical skin data of dynamic faces, enhancing modeling accuracy in computer graphics.

Findings

Successfully captures spatially-varying appearance and geometry of faces.

Quantifies biophysical skin components like hemoglobin and melanin.

Integrates seamlessly into rendering pipelines for realistic visualization.

Abstract

Acquisition and modeling of polarized light reflection and scattering help reveal the shape, structure, and physical characteristics of an object, which is increasingly important in computer graphics. However, current polarimetric acquisition systems are limited to static and opaque objects. Human faces, on the other hand, present a particularly difficult challenge, given their complex structure and reflectance properties, the strong presence of spatially-varying subsurface scattering, and their dynamic nature. We present a new polarimetric acquisition method for dynamic human faces, which focuses on capturing spatially varying appearance and precise geometry, across a wide spectrum of skin tones and facial expressions. It includes both single and heterogeneous subsurface scattering, index of refraction, and specular roughness and intensity, among other parameters, while revealing biophysically-based components such as inner- and outer-layer hemoglobin, eumelanin and pheomelanin. Our method leverages such components' unique multispectral absorption profiles to quantify their concentrations, which in turn inform our model about the complex interactions occurring within the skin layers. To our knowledge, our work is the first to simultaneously acquire polarimetric and spectral reflectance information alongside biophysically-based skin parameters and geometry of dynamic human faces. Moreover, our polarimetric skin model integrates seamlessly into various rendering pipelines.