Mirror-3DGS: Incorporating Mirror Reflections into 3D Gaussian Splatting
Jiarui Meng, Haijie Li, Yanmin Wu, Qiankun Gao, Shuzhou Yang, Jian Zhang, Siwei Ma
TL;DR
Mirror-3DGS tackles the challenge of accurate mirror reflections in 3D Gaussian Splatting by introducing a per-Gaussian mirror attribute and a plane-based mirror model to generate a virtual viewpoint behind the mirror. It constructs mirrored and original views via a learned mirror plane $\pi=(\boldsymbol{n}_{\pi}^{\top}, d)$ and a mirror transformation $\mathbf{P_m}=\mathbf{T_m}\mathbf{P_o}$, then fuses the two renders with a learned mask to produce coherent reflections without ray tracing. A two-stage training regime learns a rough Gaussian scene and the mirror plane (Stage 1) using mirror masks and depth supervision, followed by depth-aware fusion and refinement with a fixed plane (Stage 2). Across synthetic and real scenes, Mirror-3DGS achieves real-time rendering with mirror-region fidelity comparable to or better than Mirror-NeRF, while outperforming vanilla 3DGS in reflective content and significantly outperforming NeRF-based methods in speed.
Abstract
3D Gaussian Splatting (3DGS) has significantly advanced 3D scene reconstruction and novel view synthesis. However, like Neural Radiance Fields (NeRF), 3DGS struggles with accurately modeling physical reflections, particularly in mirrors, leading to incorrect reconstructions and inconsistent reflective properties. To address this challenge, we introduce Mirror-3DGS, a novel framework designed to accurately handle mirror geometries and reflections, thereby generating realistic mirror reflections. By incorporating mirror attributes into 3DGS and leveraging plane mirror imaging principles, Mirror-3DGS simulates a mirrored viewpoint from behind the mirror, enhancing the realism of scene renderings. Extensive evaluations on both synthetic and real-world scenes demonstrate that our method can render novel views with improved fidelity in real-time, surpassing the state-of-the-art Mirror-NeRF, especially in mirror regions.
