Multi-Layer Gaussian Splatting for Single-Image Feed-Forward Spatial Scene Reconstruction

Recently, 3D Gaussian Splatting (3DGS) has achieved remarkable results in 3D reconstruction and view synthesis tasks. However, single-view feed-forward 3DGS still faces significant challenges. Current state-of-the-art (SOTA) single-view 3DGS methods typically employ a small number of layers (1-2 layers) with Gaussian Splatting (GS) representations at the same resolution as the input image to address the irregularity of GS data. However, such shallow and uniform GS primitive distributions is difficult to represent occluded regions and important spatial details. Inspired by multi-plane images, this paper proposes a Multi-Layer Gaussian Splatting (MLGS) representation, which consists of shallow base GS layers for visible content and multiple occlusion GS layers dedicated to reconstructing occluded regions. The proposed MLGS representation explicitly decouples the learning processes of visible and occluded content while enhancing occlusion prediction through the following components. First, spatial stratification of GS is achieved by estimating the depth distribution range of GS primitives across different layers, forcing GS to learn spatial content reconstruction at different depths. Second, a mask-guided mechanism is proposed to effectively isolate occlusion regions and guide inpainting using spatially context-aware features. Finally, a gated convolution block is designed to dynamically modulate feature fusion to enhance reconstruction fidelity. With separate loss supervision for base and occlusion layers, MLGS enables geometrically plausible scene completion. Experiments on RealEstate10K, KITTI, and NYUv2 datasets demonstrate that the proposed method achieves SOTA performance for single-image spatial scene reconstruction.