ShadowGS: Shadow-Aware 3D Gaussian Splatting for Satellite Imagery
Feng Luo, Hongbo Pan, Xiang Yang, Baoyu Jiang, Fengqing Liu, Tao Huang
TL;DR
ShadowGS tackles shadow variability in multi-temporal satellite imagery to enable accurate 3D reconstruction. It extends 3D Gaussian Splatting with a remote-sensing physics-based rendering equation, per-Gaussian SH-based appearance, a global skylight SH, and ray-marched, geometry-aware shadows, alongside depth–normal and shadow-consistency constraints. It introduces a shadow map prior for sparse views and optimizes a multi-term loss to separate geometry, albedo, and illumination. Evaluations on DFC2019 and IARPA datasets show improved shadow disentanglement, DSM accuracy, and novel-view synthesis with minutes of training per area, across RGB, pan-sharpened, and sparse-view inputs.
Abstract
3D Gaussian Splatting (3DGS) has emerged as a novel paradigm for 3D reconstruction from satellite imagery. However, in multi-temporal satellite images, prevalent shadows exhibit significant inconsistencies due to varying illumination conditions. To address this, we propose ShadowGS, a novel framework based on 3DGS. It leverages a physics-based rendering equation from remote sensing, combined with an efficient ray marching technique, to precisely model geometrically consistent shadows while maintaining efficient rendering. Additionally, it effectively disentangles different illumination components and apparent attributes in the scene. Furthermore, we introduce a shadow consistency constraint that significantly enhances the geometric accuracy of 3D reconstruction. We also incorporate a novel shadow map prior to improve performance with sparse-view inputs. Extensive experiments demonstrate that ShadowGS outperforms current state-of-the-art methods in shadow decoupling accuracy, 3D reconstruction precision, and novel view synthesis quality, with only a few minutes of training. ShadowGS exhibits robust performance across various settings, including RGB, pansharpened, and sparse-view satellite inputs.
