3D reconstruction and relighting of objects made from scattering materials present a significant challenge due to the complex light transport beneath the surface. 3D Gaussian Splatting introduced high-quality novel view synthesis at real-time speeds. While 3D Gaussians efficiently approximate an object's surface, they fail to capture the volumetric properties of subsurface scattering. We propose a framework for optimizing an object's shape together with the radiance transfer field given multi-view OLAT (one light at a time) data. Our method decomposes the scene into an explicit surface represented as 3D Gaussians, with a spatially varying BRDF, and an implicit volumetric representation of the scattering component. A learned incident light field accounts for shadowing. We optimize all parameters jointly via ray-traced differentiable rendering. Our approach enables material editing, relighting and novel view synthesis at interactive rates. We show successful application on synthetic data and introduce a newly acquired multi-view multi-light dataset of objects in a light-stage setup. Compared to previous work we achieve comparable or better results at a fraction of optimization and rendering time while enabling detailed control over material attributes. Project page https://sss.jdihlmann.com/

翻译：由散射材料构成的物体，其三维重建与重光照因表面下复杂的光线传输而面临重大挑战。3D高斯溅射技术实现了实时高质量的新视角合成。尽管3D高斯能有效近似物体表面，却无法捕捉次表面散射的体积特性。我们提出一个框架，在给定多视角OLAT（单次单光源）数据条件下，联合优化物体形状与辐射传输场。我们的方法将场景分解为两部分：一是由3D高斯表示、具有空间变化双向反射分布函数的显式表面，二是散射分量的隐式体积表示。一个经学习得到的入射光场负责处理阴影效应。我们通过光线追踪可微分渲染联合优化所有参数。该方法支持以交互速率进行材质编辑、重光照及新视角合成。我们在合成数据上展示了成功应用，并引入一个新采集的、在光阶装置中拍摄的多视角多光源物体数据集。与先前工作相比，我们在仅需少量优化与渲染时间的情况下，取得了相当或更优的结果，同时实现了对材质属性的精细控制。项目页面 https://sss.jdihlmann.com/