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.

中文翻译：

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动态面的极化 BSSRDF 采集


偏振光反射和散射的采集和建模有助于揭示物体的形状、结构和物理特性，这在计算机图形学中越来越重要。然而，当前的极化采集系统仅限于静态和不透明物体。另一方面，鉴于人脸复杂的结构和反射特性、空间变化的地下散射的强烈存在以及它们的动态特性，人脸提出了特别困难的挑战。我们提出了一种用于动态人脸的新型偏振采集方法，该方法侧重于在各种肤色和面部表情中捕捉空间变化的外观和精确的几何形状。它包括单层和非均质亚表面散射、折射率、镜面粗糙度和强度等参数，同时揭示了基于生物物理的成分，如内层和外层血红蛋白、真黑素和黑黑素。我们的方法利用这些成分独特的多光谱吸收曲线来量化它们的浓度，这反过来又为我们的模型提供了有关皮肤层内发生的复杂相互作用的信息。据我们所知，我们的工作是第一个同时获取偏振和光谱反射信息以及基于生物物理的皮肤参数和动态人脸几何形状的工作。此外，我们的极化蒙皮模型可以无缝集成到各种渲染管道中。