3D Gaussian splatting (3DGS) has become a vital tool for learning a radiance field from multiple posed images. Although 3DGS shows great advantages over NeRF in terms of rendering quality and efficiency, it remains a research challenge to further improve the efficiency of learning 3D Gaussians. To overcome this challenge, we propose novel training strategies and losses to shorten each Gaussian list used to render a pixel, which speeds up the splatting by involving fewer Gaussians along a ray. Specifically, we shrink the size of each Gaussian by resetting their scales regularly, encouraging smaller Gaussians to cover fewer nearby pixels, which shortens the Gaussian lists of pixels. Additionally, we introduce an entropy constraint on the alpha blending procedure to sharpen the weight distribution of Gaussians along each ray, which drives dominant weights larger while making minor weights smaller. As a result, each Gaussian becomes more focused on the pixels where it is dominant, which reduces its impact on nearby pixels, leading to even shorter Gaussian lists. Eventually, we integrate our method into a rendering resolution scheduler which further improves efficiency through progressive resolution increase. We evaluate our method by comparing it with state-of-the-art methods on widely used benchmarks. Our results show significant advantages over others in efficiency without sacrificing rendering quality.
Figures & tables
Figure 2: Our method achieves the fastest training time while maintaining comparable reconstruction quality.
Figure 3: Overview of our method and effects. (a) The Gaussian list of 3DGS. (b) Distribution of Gaussian list length showing our method produces significantly shorter lists. (c) Gaussian list reduction after applying scale reset. (d, e) Scale and opacity distributions comparing 3DGS and 3DGS with scale reset, showing scale reset produces smaller Gaussians with higher opacities. (f) Gaussian list reduction after applying entropy regularization. (g, h) Scale and opacity distributions comparing 3DGS and 3DGS with entropy regularization, demonstrating entropy constraint produces smaller Gaussians and more polarized opacities. “3DGS” results are produced with LiteGS.
Figure 5: A toy example demonstrating how entropy regularization polarizes Gaussian weights along a ray.
Method
Iters
Mip-NeRF 360
Deep Blending
Tanks and Temples
NG
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
NG
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
NG
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
AdR-Gaussian
30K
1.3M
26.92
0.792
0.257
504.86
1.4M
29.72
0.905
0.250
515.78
0.9M
23.49
0.835
0.202
321.08
EDGS
5K
3.5M
26.46
0.817
0.205
318.06
2.3M
29.08
0.898
0.260
214.76
2.2M
22.23
0.831
0.184
219.06
Mini-Splatting2-Dense
18K
3.6M
27.56
0.827
0.184
220.22
4.2M
29.78
0.908
0.222
162.38
2.6M
23.43
0.852
0.152
162.24
3DGS
30K
3.3M
27.55
0.819
0.209
919.51
2.8M
29.74
0.907
0.237
963.66
1.8M
23.77
0.854
0.166
560.52
Taming-3DGS
27.85
0.823
0.208
402.54
30.07
0.910
0.234
322.06
24.14
0.855
0.169
243.25
Table 1: Quantitative comparison across three datasets. We follow Taming-3DGS’s target Gaussian count setup (3.3M, 2.8M, 1.8M for the three datasets respectively) for fair comparison. For methods whose Gaussian number cannot be controlled, we report their default counts.
Method
Iters
Mip-NeRF 360
Deep Blending
Tanks and Temples
NG
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
NG
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
NG
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
Mini-Splatting2
18K
0.6M
27.38
0.821
0.215
92.68
0.6M
30.11
0.912
0.239
78.87
0.4M
23.11
0.841
0.186
72.45
DashGaussian
26.89
0.777
0.284
65.01
29.93
0.901
0.270
48.11
23.42
0.823
0.229
57.94
LiteGS
26.75
0.765
0.299
66.33
29.75
0.903
0.275
49.16
23.07
0.816
0.234
49.74
Ours
18K
0.6M
26.49
0.762
0.303
43.87
0.6M
29.43
0.898
0.278
37.76
0.4M
22.96
0.819
0.226
44.81
Table 2: Quantitative comparison with 18K iterations and fewer Gaussians, following Mini-Splatting2’s setup. The performance gap compared to Tab. 1 stems from LiteGS backbone limitations under constrained settings, not our acceleration strategy.
Figure 6: Per-iteration training time breakdown.
Figure 7: Qualitative comparison of rendered results. Each row shows results from 3DGS, Taming 3DGS, DashGaussian, LiteGS, and ours with PSNR and training time. More comparisons are detailed in Fig. 16 , Fig. 17 , Fig. 18 and Fig. 19 of the supplementary material.
Figure 8: Qualitative comparison of rendering results, comparing our method with DashGaussian. Each row shows results at certain training times with PSNR and SSIM metrics displayed. More comparisons are detailed in Fig. 20 of the supplementary material.
Method
Iters
NG
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
FastGS
30K
0.4M
27.43
0.797
0.261
88.55
Ours
30K
0.4M
26.50
0.754
0.314
66.32
Table 3: Quantitative comparison with FastGS on Mip-NeRF 360 under FastGS’s default setting (0.4M Gaussians).
Method
Mip-NeRF 360
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
L
27.75
0.822
0.208
191.17
L+R
27.33
0.815
0.212
147.33
L+E
27.35
0.815
0.218
162.53
L+R+E
27.14
0.812
0.215
141.28
L+D
27.85
0.822
0.213
134.99
Table 4: Ablation study analyzing effects of individual modules.
Method
Mip-NeRF 360
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
L+D+R(0.2)+E(0.01)
27.35
0.811
0.222
102.86
L+D+R(0.2)+E(0.02)
27.14
0.808
0.226
99.10
L+D+R(0.3)+E(0.015)
27.31
0.811
0.223
104.39
L+D+R(0.1)+E(0.015)
27.14
0.807
0.227
98.34
L+D+R(0.2)+E(0.015)
27.28
0.810
0.224
99.58
Table 5: Ablation study on parameter selection.
Method
Mip-NeRF 360
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
L+D+V(1.0)+E(0.015)
27.17
0.808
0.230
107.91
L+D+R(0.2)+E(0.015)
27.28
0.810
0.224
99.58
Table 6: Comparison of volume regularization versus scale reset.
Method
Mip-NeRF 360
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
L+D+R(0.2)+O(3.0)
27.29
0.807
0.231
106.16
L+D+R(0.2)+E(0.015)
27.28
0.810
0.224
99.58
Table 7: Comparison of opacity versus entropy constraint.
Method
Mip-NeRF 360
PSNR ↑
SSIM ↑
LPIPS ↓
Time(s) ↓
3DGS (16 × 16)
27.55
0.819
0.209
919.51
3DGS (8 × 8)
27.56
0.819
0.208
1004.30
Table 8: Ablation study of tile size impact on time and quality.
Figure 9: Training time versus iterations. Plot for compact models are shown in Supplementary Fig. 13 .
Figure 10: PSNR convergence across iterations. Plot for compact models is shown in Supplementary Fig. 14 .
Figure 11: Comparison of Gaussian list length distributions across individual and combined modules.
Figure 12: Gaussian count heatmap comparison across modules. Colors represent per-tile Gaussian counts. See color bar in Fig. 1 .
Method
FPS ↑
3DGS
140.91
Taming
219.60
LiteGS
233.76
Ours
343.92
Table 9: Average testing FPS on the Mip-NeRF 360 dataset.
Figure 13: Training time versus iterations for full and compact models, corresponding to Fig. 9 .
Figure 14: PSNR convergence across iterations for full and compact models, corresponding to Fig. 10 .
Figure 15: PSNR and time curves across iterations showing effects of individual modules. See Sec. 5.4 for more details.
Figure 16: Qualitative comparison of rendered results on scene Stump. Our method achieves comparable rendering quality (PSNR: 27.33) while being the fastest, with training time of only 87.62 seconds.
Figure 17: Qualitative comparison of rendered results on scene Counter. Our method achieves comparable rendering quality (PSNR: 30.38) while being the fastest, with training time of only 86.66 seconds.
Figure 18: Qualitative comparison of rendered results on scene Bicycle. Our method achieves comparable rendering quality (PSNR: 21.29) while being the fastest, with training time of only 115.37 seconds.
Figure 19: Qualitative comparison of rendered results on scene Room. Our method achieves comparable rendering quality (PSNR: 34.23) while being the fastest, with training time of only 79.42 seconds.
Figure 20: Qualitative comparison of rendering quality across two scenes from Mip-NeRF 360, comparing our method with DashGaussian. Each row shows results at training times of 15s, 30s, 50s, 70s, and 90s. PSNR and SSIM metrics are displayed in each image.
Figure 21: Gaussian count heatmap comparison across scenes in Mip-NeRF 360 dataset, corresponding to Fig. 1 . Each row shows ground truth and heatmaps for 3DGS, Taming-3DGS, LiteGS, and our method. Colors represent per-tile Gaussian counts, where purple indicates low counts and yellow indicates high counts. Our method consistently achieves the lowest Gaussian counts (darker colors).
Figure 22: Gaussian count heatmap comparison across scenes in Mip-NeRF 360 dataset for ablation study, corresponding to Fig. 12 . Each row shows ground truth and heatmaps for 3DGS, 3DGS+Scale Reset, 3DGS+Entropy Constraint, and 3DGS+Reset+Entropy. Colors represent per-tile Gaussian counts, where purple indicates low counts and yellow indicates high counts.
Figure 23: Per-pixel entropy heatmap comparison between LiteGS and our method across scenes in the Mip-NeRF 360 dataset. Darker colors correspond to lower entropy.
Figure 24: Distribution comparison per scene across all methods on length, scale, and opacity. Results labeled as “3DGS” are obtained using LiteGS. See Sec. 5.4 for more details.
Figure 25: Visualization of Gaussians on selected scenes from the Mip-NeRF 360 dataset. Compared to 3DGS, our method produces smaller and more compact Gaussians.
3D Gaussian Splatting (3DGS) enables real-time novel view synthesis, but existing general-purpose acceleration methods suffer severe rendering quality degradation when extended to more complex, large-scale scenes. To address this issue, we propose EffGS, a more general acceleration framework that improves training and rendering efficiency while maintaining reconstruction quality comparable to or better than vanilla 3DGS across bounded and large-scale scenes. EffGS combines frequency-aware guidance, localized density control, and adaptive primitive scale modulation. First, an importance scoring mechanism combines pixel-wise reconstruction errors with a difference-of-Gaussians mask scheduled over training to provide stage-dependent spatial guidance. Second, localized densification and pruning restricts density modifications to Gaussians with valid projected footprints in the sampled views. Third, learnable per-Gaussian scale modulation adjusts effective primitive extent during optimization while retaining the Compact Box rasterization rule. Extensive experiments on bounded and large-scale scene datasets demonstrate a favorable balance between reconstruction quality, training time, and primitive count. Component ablations and matched-primitive-budget comparisons further support the effectiveness of the framework.
Changbai Li, Shuo Yang, Yichen Yang +2
Beihang University · Nanyang Technological University
3D Gaussian Splatting (3DGS) achieves state-of-the-art rendering quality at real-time speeds but suffers from "model bloat" - a large number of redundant, low-opacity Gaussians that inflate memory usage and training costs. This inefficiency stems from the standard "densify-then-prune" paradigm, which expands the model aggressively before relying on pruning to achieve compactness. To mitigate this problem, we present an efficient training framework that builds an intrinsically compact representation, replacing the conventional densify-then-prune cycle. Our method leverages a synergistic design: an L2 reconstruction loss to provide error-proportional gradients that stabilize optimization, and a novel Polarized Opacity Prior (POP) to actively manage the Gaussian population. POP steers informative primitives toward full opacity and uninformative ones toward transparency, enabling natural pruning and accelerating rendering through Early Ray Termination. Experiments on three public datasets demonstrate that our approach consistently achieves accelerated 3DGS training with significantly fewer Gaussians while maintaining comparable visual reconstruction quality. These results show that the proposed framework provides a simple and effective path toward fast and inherently compact 3DGS training.
Zi-Ming Wang, Kai-Wen Duan, Kowei Huang +2
National Tsing Hua University, Taiwan · National Institute of Informatics, Japan
3D Gaussian Splatting (3DGS) has revolutionized novel-view synthesis with its fast and high-fidelity rendering. However, rendering at high FPS and low latency across various scenes remains a challenge, especially when large amounts of 3D Gaussian ellipsoids appear in the scene. To address this issue, we introduce TemporalGS, to the best of our knowledge, the first training-free plug-and-play algorithmic approach to accelerate 3DGS rendering without any post-training or post-processing, implemented on top of tile-based software rasterization. The key idea is that, instead of rendering frames independently as 3DGS, we leverage the temporal priors, represented by novel geometry and appearance buffers, etc., to reduce redundancy of Gaussian preprocessing, sorting, and rasterization operations of consecutive frames. Specifically, we propose two acceleration strategies: (1) temporal dynamic culling, which filters out Gaussians that contribute less to current frame rendering; (2) selective rendering, which renders only a small portion of tiles that cannot be approximated by the temporal priors. By adapting and interleaving these two strategies, TemporalGS yields a simple but effective plug-and-play solution for 3DGS rendering speed-up without any training. Extensive experiments show that TemporalGS achieves comparable or even better performance compared to existing state-of-the-art post-training or post-processing-based 3DGS rendering acceleration approaches. TemporalGS can significantly enhance the rendering speed of various 3DGS methods, achieving up to 1.48× acceleration, while maintaining competitive rendering quality. We further extend our TemporalGS to hardware rasterization-based 3DGS to show the portability of our algorithm.
Yuhongze Zhou, Zihao Yang, Xinxin Zuo +1
McGill University, Montr´eal, Canada · University of Waterloo, Waterloo, Canada · Concordia University, Montr´eal, Canada +1