TSPE-GS: Probabilistic Depth Extraction for Semi-Transparent Surface Reconstruction via 3D Gaussian Splatting
Zhiyuan Xu, Nan Min, Yuhang Guo, Tong Wei
TL;DR
TSPE-GS addresses the failure of single-depth assumptions in 3D Gaussian Splatting when reconstructing semi-transparent scenes. By modeling per-pixel depth as a multi-modal distribution over sampled transmittances and extracting multiple surface depths via peak detection, it enables simultaneous outer and inner surface reconstruction. The method integrates these multi-layer depths through progressive TSDF fusion, preventing interference between layers. Experiments on semi-transparent and opaque datasets show significant gains in semi-transparent geometry without sacrificing opaque performance, and the approach remains a plug-and-play enhancement for Gaussian-based pipelines.
Abstract
3D Gaussian Splatting offers a strong speed-quality trade-off but struggles to reconstruct semi-transparent surfaces because most methods assume a single depth per pixel, which fails when multiple surfaces are visible. We propose TSPE-GS (Transparent Surface Probabilistic Extraction for Gaussian Splatting), which uniformly samples transmittance to model a pixel-wise multi-modal distribution of opacity and depth, replacing the prior single-peak assumption and resolving cross-surface depth ambiguity. By progressively fusing truncated signed distance functions, TSPE-GS reconstructs external and internal surfaces separately within a unified framework. The method generalizes to other Gaussian-based reconstruction pipelines without extra training overhead. Extensive experiments on public and self-collected semi-transparent and opaque datasets show TSPE-GS significantly improves semi-transparent geometry reconstruction while maintaining performance on opaque scenes.
