Creating photorealistic human heads typically involves trade-offs between representation power, efficiency, and generalizability. Traditional mesh-based solutions relying on 3DMMs generally sacrifice representation power but are efficient to render. On the other hand, NeRF-based methods improve representation power and fidelity while sacrificing efficiency. Gaussian splatting methods attempt to resolve these trade-offs by offering both high representation power and efficiency with real-time rendering. However, their efficiency nonetheless depends on the number of rasterized Gaussians, and the time needed to optimize and prepare the head (the enrollment time) is often high. In light of this, we propose EGGHead, which introduces a novel Gaussian allocation algorithm that efficiently assigns Gaussians to the head's semantic regions given a fixed Gaussian budget. Our algorithm reduces the number of Gaussians needed while minimizing the impact on representation power. EGGHead operates in a single forward pass and outperforms previous single-image face modeling methods in reconstruction quality, novel view synthesis, and rendering speeds.
Figures & tables
Figure 2: Training Pipeline. We propose a single-image, generalizable, and lightweight Gaussian head model that adaptively allocates M Gaussians with minimal impact on rendering quality. Secs. 3.1–3.4 constitute the main reconstruction pipeline: GAM first allocates M Gaussians from the source image, Voronoi tessellation provides sparse geometric priors, and image/depth features are used to predict Gaussian attributes for rendering and refinement. Sec. 3.5 is trained in parallel to predict a density map supervised by the GAM-derived density map. It is independent of the main reconstruction pipeline during training and is used at inference time for density-based Gaussian allocation.
Figure 3: Inference-time Pipeline. During inference, we replace GAM with density-based sampling to reduce computation, and incorporate a Face Symmetry Module to complete occluded regions.
Figure 5: Reconstruction Quality. We compare the reconstruction quality on the FFHQ and CelebA-HQ datasets. (a) E 3 DGE; (b) G-NeRF; (c) GAGAvatar; (d) Ours.
Method
FFHQ
CelebA-HQ
PSNR ↑
SSIM ↑
LPIPS ↓
PSNR ↑
SSIM ↑
LPIPS ↓
E 3 DGE [ 52 ]
23.43
0.598
0.133
23.64
0.589
0.128
G-NeRF [ 98 ]
19.68
0.673
0.256
19.81
0.566
0.296
GAGAvatar [ 17 ]
25.03
0.888
0.110
25.06
0.874
0.119
Ours
29.75
0.951
0.017
29.25
0.939
0.018
Table 1: Reconstruction Quality. We quantitatively compare the reconstruction quality.
Method
FFHQ
CelebA-HQ
ID ↑
FID ↓
ID ↑
FID ↓
E 3 DGE [ 52 ]
0.7744
41.60
0.7547
40.87
G-NeRF [ 98 ]
0.6621
54.67
0.6375
50.45
GAGAvatar [ 17 ]
0.8377
32.55
0.8480
30.01
Ours
0.8517
29.01
0.8532
32.23
Table 2: Novel View Synthesis. We compare novel view synthesis quality using pairwise multi-view identity consistency (ID) and Frechet Inception Distance (FID).
Table 3: NeRSemble NVS. Quantitative comparison on the NeRSemble dataset.
Method
Enrollment time (sec)
Render speed (FPS)
E 3 DGE [ 52 ]
8.63
5.26
G-NeRF [ 98 ]
5.96
33.61
GAGAvatar [ 17 ]
0.06
43.43
Ours
1.54
121.19
Table 4: Efficiency. We compare efficiency in enrollment time and rendering speed.
Figure 7: Ablation on Sampling Strategy. M=12 k . (a) Landmark; (b) Parsing; (c) Uniform; (d) Ours.
M
Method
PSNR ↑
SSIM ↑
LPIPS ↓
12 k
Landmark
28.64
0.936
0.024
Parsing
29.02
0.943
0.022
Uniform
29.13
0.953
0.019
Adaptive (Ours)
29.75
0.951
0.017
8 k
Landmark
28.06
0.918
0.032
Parsing
28.35
0.925
0.030
Table 5: Ablation on Sampling Strategy. We evaluate whether our allocation strategy (adaptive) more effectively distributes Gaussians under a fixed budget M compared to uniform and landmark sampling. Our method achieves better reconstruction quality across M settings, with lower SSIM than uniform sampling.
Figure 8: Ablation on Voronoi Tessellation. We show the impact of Voronoi tessellation (VT) on capturing 3D Gaussian shapes under single-view and sparse-Gaussian settings.
Figure 9: Ablation on Mirroring Gaussians. We show the effect of mirroring Gaussians for handling occluded regions. Our method naturally fills in the occluded areas.
Layer
Filter Size
Input Channel
Output Channel
Activation
Conv
5×5
3
32
ReLU
E1
3×3
32
32
ReLU
E2
3×3
32
48
ReLU
E3
3×3
48
96
ReLU
D3
3×3
192
96
ReLU
D2
3×3
192
64
ReLU
Table 6: Structure of Gaussian Attribute Regressor.
Layer
Filter Size
Input channel
Output channel
Activation
E1
3×3
3
32
ReLU
E2
3×3
32
64
ReLU
E3
3×3
64
128
ReLU
E4
3×3
128
256
ReLU
D3
2×2
256
128
ReLU
D2
2×2
128
64
ReLU
Table 7: Structure of Density Prediction Network.
Layer
Filter Size
Input channel
Output channel
Activation
E1
3×3
4
48
SiLU
E2
3×3
48
96
SiLU
E3
3×3
96
192
SiLU
E4
3×3
192
384
SiLU
M
3×3
384
384
SiLU
D3
3×3
576
192
SiLU
Table 8: Structure of Refinement Network.
Figure 10: Edge-aware alignment. Aligning Gaussian positions along the edges improves boundary consistency and reduces artifacts compared to the unaligned configuration.
Figure 11: Predicted Density Map. The predicted density maps align well with the GT density maps and assign higher density to fine detail regions which enables adaptive Gaussian allocation.
Number of Gaussians ( M )
Rendering speed (FPS)
120 k
179.91
80 k
214.01
40 k
240.24
12 k
309.60
8 k
316.62
4 k
331.11
Table 9: Rendering Speed. We report rendering speed for different numbers of Gaussians without additional refinement steps.
Figure 12: Expression Editing. We show the expression from the driving image is properly transferred to the source identity by deforming Gaussians bound to the mesh.
Figure 13: Additional Comparisons. We show improvements in preserving facial details, hair texture, and eye structure/color, and also better reconstructing occluded face regions ( e.g. recovering the subject’s occluded ear in the fourth row).
M
Method
PSNR ↑
SSIM ↑
LPIPS ↓
24 k
GAGAvatar [ 17 ]
21.72
0.837
0.100
12 k
Ours
22.91
0.835
0.096
Table 10: Additional NeRSemble NVS. Additional quantitative comparison on the NeRSemble dataset using 12 k Gaussians for our method and 24 k Gaussians for GAGAvatar.
Figure 14: Delighting Preprocessing. We apply an off-the-shelf delighting method to the input image during enrollment to reduce asymmetric illumination artifacts.