Insta360

G2PS: Geometry and Gradient-based Partitioning for
Panoramic Outdoor Reconstruction

Weijian Chen1,2, Weibo Yao1,3, Yuhang Zhang1, Xiaolin Tang1, Guo Wang1,
Weijun Zhang1, Xitong Gao4, Yihao Chen1, Hongde Qin5, Lu Qi1,6

1Insta360 Research   2Sun Yat-sen University   3South China University of Technology  
4University of Chinese Academy of Sciences   5Harbin Engineering University   6Wuhan University

Now available: The paper and training code are released. The dataset and a 3DGS rendering plugin built on UE 5.8 — the first rendering plugin to support the latest Unreal Engine — are coming in mid-July 2026. Stay tuned.
GT Training

Abstract

Scaling 3D Gaussian Splatting (3DGS) to large outdoor scenes is costly in both data acquisition and computation. Adopting panoramic images with equirectangular projection (ERP) can reduce capture effort via their full 360° field of view, yet the resulting omnipresent visibility invalidates existing partitioning strategies that rely on local camera frustums, causing block-wise optimization to degenerate into global training. We propose PanoLOG, a two-stage coarse-to-fine framework equipped with a Geometry and Gradient-based Partitioning Strategy (G2PS) tailored for large-scale panoramic 3DGS reconstruction. PanoLOG combines panorama-specific geometric priors in a global coarse stage with an adaptive, importance-aware partitioning scheme in the refinement stage, enabling truly block-parallel training under 360° visibility. We further construct Pano360, the first large-scale panoramic outdoor benchmark for 3DGS reconstruction. Extensive experiments demonstrate that PanoLOG achieves state-of-the-art rendering quality while maintaining scalable, block-parallel training.

Full algorithmic details of G2PS will be disclosed in our forthcoming publication.

PanoLOG overview: sky-level and ground-level renderings of large-scale outdoor reconstructions
Figure 1: Overview of PanoLOG for scalable large-scale outdoor reconstruction.

Visual Results

All videos above are rendered from our trained model.

Qualitative Comparisons

Qualitative comparison between PanoLOG and existing methods across diverse large-scale scenes
Comprehensive comparison between PanoLOG and four existing methods. Our method excels in reconstructing distant regions and complex glass facades.

Quantitative Results

MethodNSCNSK
PSNR↑SSIM↑LPIPS↓Model Size↓ (MB)PSNR↑SSIM↑LPIPS↓Model Size↓ (MB)
H3DGS27.77870.85640.24571002.124.14800.81540.19341843.2
CityGaussian27.73400.84530.2609523.724.82700.81760.19831126.4
DOGS26.84860.81860.27691024.024.46060.79800.21741536.3
Momentum-GS26.45680.83110.2625802.523.91230.79790.19861024.0
Ours28.18380.85940.2435463.524.63870.82430.1916544.0
MethodBAXNSN
PSNR↑SSIM↑LPIPS↓Model Size↓ (MB)PSNR↑SSIM↑LPIPS↓Model Size↓ (MB)
H3DGS20.71040.66260.39367577.623.44640.75300.30185734.4
CityGaussian19.83610.59950.4902418.521.94920.67290.4221526.6
DOGS19.60940.57450.5203671.822.67430.65870.4454774.9
Momentum-GS20.09930.59990.48961024.022.97460.70520.37031331.2
Ours21.34680.66560.41691331.224.60950.75080.3347766.8
MethodRicoh360360Roam
PSNR↑SSIM↑LPIPS↓PSNR↑SSIM↑LPIPS↓
OmniGS26.000.8280.21024.930.8000.253
3DGS26.260.8250.22524.980.8000.271
ODGS22.710.7480.32619.740.6270.476
SpaGS26.110.8320.24325.450.8140.223
Ours26.480.8450.18325.830.8210.222

Comparisons on Public Datasets

Qualitative comparison of PanoLOG against four prior methods on public panoramic datasets
Qualitative comparison against four prior methods on the Ricoh360 and 360Roam datasets. PanoLOG preserves finer geometry and texture across diverse outdoor scenes.

Ablation Studies

Ablation comparison of the full PanoLOG model against variants with selected components disabled
Ablation on two representative scenes. Each component of G2PS contributes to the final reconstruction quality.

Citation

@article{panolog2026,
  title   = {Geometry and Gradient-based Partitioning for Panoramic Outdoor Reconstruction},
  author  = {Chen, Weijian and Yao, Weibo and Zhang, Yuhang and Tang, Xiaolin and
             Wang, Guo and Zhang, Weijun and Gao, Xitong and Chen, Yihao and
             Qin, Hongde and Qi, Lu},
  journal = {arXiv preprint arXiv:2607.08769},
  year    = {2026}
}