Feature extraction, matching, structure from motion (SfM), and novel view synthesis (NVS) have traditionally been treated as separate problems with independent optimization objectives. We present GloSplat, a framework that performs joint pose-appearance optimization during 3D Gaussian Splatting training. Unlike prior joint optimization methods (BARF, NeRF--, 3RGS) that rely purely on photometric gradients for pose refinement, GloSplat preserves explicit SfM feature tracks as first-class entities throughout training: track 3D points are maintained as separate optimizable parameters from Gaussian primitives, providing persistent geometric anchors via a reprojection loss that operates alongside photometric supervision. This architectural choice prevents early-stage pose drift while enabling fine-grained refinement -- a capability absent in photometric-only approaches. We introduce two pipeline variants: (1) GloSplat-F, a COLMAP-free variant using retrieval-based pair selection for efficient reconstruction, and (2) GloSplat-A, an exhaustive matching variant for maximum quality. Both employ global SfM initialization followed by joint photometric-geometric optimization during 3DGS training. Experiments demonstrate that GloSplat-F achieves state-of-the-art among COLMAP-free methods while GloSplat-A surpasses all COLMAP-based baselines.
Figures & tables
Figure 1: Accuracy vs. Speed. Average PSNR on MipNeRF360 vs. runtime for 1000 images (Courthouse scene). GloSplat-F achieves 13.3 × speedup over GPU-accelerated COLMAP+3DGS while improving PSNR by +0.38 dB. GloSplat-A achieves the highest accuracy (28.86 dB), surpassing all baselines. Our joint pose-appearance optimization enables both variants to occupy the Pareto frontier. (All methods benchmarked on the same GPU; see Appendix C for details.)
Figure 2: GloSplat Pipeline. Given unposed input images, local correspondences are extracted (frozen preprocessing): XFeat+LightGlue with retrieval-based pairs (GloSplat-F) or SIFT with exhaustive matching (GloSplat-A). Global SfM simultaneously estimates all camera poses through rotation averaging, positioning, and bundle adjustment, providing robust initialization. Joint 3DGS training (our core contribution) then continuously refines poses through a reprojection-based BA loss while optimizing Gaussian primitives, enabling combined photometric-geometric supervision that prevents drift and improves reconstruction quality.
MipNeRF360
Tanks and Temples
CO3Dv2
Method
PSNR ↑
SSIM ↑
LPIPS ↓
PSNR ↑
SSIM ↑
LPIPS ↓
PSNR ↑
SSIM ↑
LPIPS ↓
3DGS †
27.39
0.815
0.185
24.85
0.851
0.155
32.58
0.938
0.095
MCMC †
27.91
0.836
0.154
25.76
0.867
0.139
33.21
0.941
0.097
MCMC
22.19
0.548
0.282
21.42
0.679
0.278
25.71
0.712
0.201
CF-3DGS
12.38
0.234
0.719
12.19
0.391
0.608
20.18
0.611
0.435
HT-3DGS
14.79
0.380
0.669
13.83
0.451
0.585
28.28
0.833
0.230
Table 1: Comparison with state-of-the-art methods on novel view synthesis. † indicates COLMAP initialization. Best COLMAP-free results in bold . GloSplat-F (retrieval-based) achieves SOTA among COLMAP-free methods.
Figure 3: Runtime Comparison on Courthouse Scene. End-to-end reconstruction time (in seconds) as a function of the number of input images. All methods use the same GPU (RTX PRO 6000); COLMAP is compiled with CUDA and uses GPU acceleration for feature extraction/matching. GloSplat-F achieves 13.3 × speedup over COLMAP at 1000 images due to retrieval-based pair selection and parallel global SfM. VGGT-X is faster at smaller scales but GloSplat-F surpasses it at 750+ images due to better asymptotic scaling.
Method
PSNR ↑
SSIM ↑
LPIPS ↓
3DGS
27.48
0.815
0.216
AbsGS
27.52
0.820
0.198
PixelGS
27.62
0.824
0.189
MiniSplatting-D
27.57
0.832
0.176
TamingGS
27.96
0.822
0.207
3DGS-MCMC
28.01
0.835
0.186
Table 2: Comparison with COLMAP-based methods on MipNeRF360. All baselines use COLMAP poses. GloSplat-A achieves SOTA among all methods. Best in bold , second best underlined .
COLMAP
3RGS
GloSplat-F (Ours)
Scene
R(°) ↓
ATE(m) ↓
PSNR ↑
R(°) ↓
ATE(m) ↓
PSNR ↑
R(°) ↓
ATE(m) ↓
PSNR ↑
0079_00
3.55
0.014
30.78
2.45
0.014
32.58
2.12
0.011
33.42
0301_00
133.83
0.169
23.63
9.30
0.009
30.11
7.82
0.007
31.24
0418_00
5.03
0.012
29.03
4.34
0.012
31.62
3.78
0.010
32.35
Table 3: Comparison with COLMAP and 3RGS on ScanNet. Best in bold , second best underlined .
Appendix figures & tables8 assets
Supplementary material from the paper’s appendix.
Appendix
Figure 4: Qualitative Comparison on MipNeRF360. We compare novel view synthesis results from GloSplat-A, GloSplat-F, VGGT-X, and Improved-GS against ground truth. GloSplat-A achieves significantly higher PSNR and lower LPIPS across all scenes. On Bonsai , GloSplat-A outperforms VGGT-X by +8.57 dB PSNR . On Flowers , our method shows +6.76 dB PSNR and 46% lower LPIPS (0.147 vs 0.273) over VGGT-X. On Garden , GloSplat-A achieves +5.69 dB over VGGT-X. Best viewed zoomed in.
Scene
PSNR ↑
SSIM ↑
LPIPS ↓
Apple
35.30
0.952
0.063
Bench
32.33
0.931
0.089
Hydrant
29.33
0.920
0.071
Skateboard
33.35
0.943
0.116
Teddybear
33.24
0.932
0.102
Average
32.71
0.936
0.088
Appendix
Table 4: Per-scene results on CO3Dv2 dataset.
Scene
PSNR ↑
SSIM ↑
LPIPS ↓
Bicycle
25.98
0.802
0.145
Bonsai
33.16
0.952
0.114
Counter
29.60
0.921
0.131
Flowers
22.93
0.688
0.244
Garden
27.64
0.866
0.084
Kitchen
32.99
0.942
0.085
Appendix
Table 5: Per-scene results on MipNeRF360 dataset.
Scene
PSNR ↑
SSIM ↑
LPIPS ↓
Barn
26.43
0.842
0.168
Caterpillar
24.89
0.851
0.162
Ignatius
27.15
0.912
0.121
Truck
25.31
0.867
0.148
Train
25.32
0.873
0.156
Average
25.82
0.869
0.151
Appendix
Table 6: Per-scene results on Tanks and Temples dataset.
Method
250 imgs
500 imgs
750 imgs
1000 imgs
COLMAP
644.6
1165.0
2226.3
4349.2
3RGS (MASt3R)
312.2
638.0
978.5
1308.2
GloSplat-A
222.2
408.2
855.7
1371.3
VGGT-X
53.9
113.3
249.6
398.9
GloSplat-F
100.2
191.9
250.0
327.8
Speedup vs COLMAP
Appendix
Table 7: Runtime comparison (seconds) on Courthouse scene with varying image counts. All methods run on the same hardware (RTX PRO 6000 GPU); COLMAP uses GPU-accelerated SIFT and matching. GloSplat-F achieves superior scaling due to O(n) pair selection and parallel global SfM.
Configuration
Training Time
Overhead
MCMC 3DGS (vanilla)
∼ 31 min
–
MCMC 3DGS + Joint Opt (Ours)
∼ 32 min
+3%
Appendix
Table 8: Training time comparison between vanilla MCMC 3DGS and MCMC 3DGS with joint optimization (30k iterations, 200 images). Joint optimization adds minimal overhead while providing +0.81 dB improvement.
Configuration
PSNR ↑
Δ
SSIM ↑
LPIPS ↓
Reference Configurations
GloSplat-A (exhaustive matching)
28.86
+1.09
0.862
0.139
GloSplat-F (retrieval matching)
27.77
–
0.818
0.164
MCMC † (COLMAP, frozen poses)
27.91
+0.14
0.836
0.154
(A) Joint Optimization — removing from GloSplat-F
Frozen poses after Global SfM
19.18
–8.59
0.463
0.472
Appendix
Table 9: Ablation study on MipNeRF360. We show reference configurations (top) and ablations organized by component. Δ shows change from GloSplat-F. Best in bold ; “–” indicates failure.
Configuration
PSNR ↑
SSIM ↑
LPIPS ↓
GloSplat-A (separate tracks)
28.86
0.862
0.139
GloSplat-A (merged tracks)
28.64
0.858
0.144
Δ
–0.22
–0.004
+0.005
GloSplat-F (separate tracks)
27.77
0.818
0.164
GloSplat-F (merged tracks)
27.58
0.813
0.168
Δ
–0.19
–0.005
+0.004
Appendix
Table 10: Ablation: Separating track points from Gaussian means. Merging tracks with Gaussians degrades all metrics for both variants, validating our architectural choice.
We present StructSplat, a feed-forward and generalizable 3D Gaussian reconstruction framework that operates directly on uncalibrated images without requiring camera parameters. Existing methods either rely on per-scene optimization or assume known camera poses, and often entangle geometry and appearance within a unified backbone, limiting reconstruction fidelity and generalization. Our key idea is to adopt a structured representation that organizes geometry, semantic, and texture cues with explicit roles in the reconstruction process. Specifically, we introduce a pixel-aligned feature injection mechanism to enable accurate texture modeling from 2D observations, incorporate semantic-aware priors to improve global consistency, and design a camera alignment strategy to prevent information leakage and improve generalization. Experiments show that our method significantly outperforms prior approaches on challenging benchmarks. On DL3DV, our method achieves 28.045 PSNR, surpassing AnySplat (22.377) by +5.67 dB. In cross-dataset evaluation, our method achieves +1.94 dB over AnySplat on ACID and +1.72 dB on RealEstate10K. Project page: https://structsplat.github.io Code: https://github.com/J-C-Zhao/StructSplat
Jia-Chen Zhao, Beiqi Chen, Xinyang Chen +2
Harbin Institute of Technology (Shenzhen) · Great Bay University · Guangzhou CloudButterfly Technology Co., Ltd.
This paper introduces a fast method for high-quality 3D Gaussian Splatting (3DGS) reconstruction without traditional Structure-from-Motion (SfM). The proposed approach leverages 3D Foundation Models (3DFMs) for camera pose and point-cloud initialization, then jointly optimizes both camera poses and Gaussian primitives using a depth-guided loss function. This enables fast convergence even from rough initialization with as few as 50-60 input views. To further improve reconstruction quality in sparse-view scenarios, an MLP-based pose refinement module is introduced alongside depth-guided supervision from the foundation model. Extensive experiments on Mip-NeRF 360, Tanks and Temples, and RobustNeRF demonstrate that the proposed method achieves competitive reconstruction quality (23.61 dB PSNR, 0.19 LPIPS) while reducing training time to approximately three minutes per scene. The proposed method produces ready-to-use 3DGS models at a fraction of the time required by existing pipelines, making it suitable for near real-time applications in robotics, VR, and autonomous navigation.
Anurag Dalal, Daniel Hagen, Kjell G. Robbersmyr +1
Dep. of Eng. Sciences University of Agder Grimstad, Norway · Top Research Centre Mechatronics University of Agder Grimstad, Norway
Feed-forward 3D Gaussian Splatting (3DGS) promises instant scene reconstruction with high-quality novel-view synthesis. Yet, fine-grained geometry and appearance remain difficult to recover, motivating us to revisit how feed-forward models represent, aggregate, and refine detailed visual information. We introduce FineSplat, a feed-forward 3DGS framework built around fine-grained image patches. Since global multi-view attention becomes prohibitively expensive at such high token resolutions, we develop a dual-grouping strategy that combines two complementary forms of locality: view-wise grouping enables efficient interaction among neighboring views, while 3D spatial grouping reconnects geometrically related tokens that may never have interacted under view-wise grouping by lifting them into the 3D scene space. We further leverage reconstruction error as direct feedback, providing an explicit rendering-based signal to recover fine-grained structures and appearance, thereby overcoming the limitations of one-pass feed-forward prediction. Finally, a compact Gaussian generation scheme preserves the benefits of fine-grained features without unnecessarily increasing the number of primitives. Together, these designs enable FineSplat to recover richer geometry and appearance while remaining efficient and compact, achieving state-of-the-art results by a substantial margin, under the same or smaller Gaussian budgets than existing methods.