Organizations: Advanced Research Center on Electronic System (ARCES) · Department of Computer Science and Engineering (DISI), University of Bologna, Italy · TU Berlin, Robotics Institute Germany, Einstein Center Digital Future, SCIoI Excellence Cluster, Germany
We propose EventHub, a novel framework for training deep-event stereo networks without ground truth annotations from costly active sensors, relying instead on standard color images. From these images, we derive either proxy annotations and proxy events through state-of-the-art novel view synthesis techniques, or simply proxy annotations when images are already paired with event data. Using the training set generated by our data factory, we repurpose state-of-the-art stereo models from RGB literature to process event data, obtaining new event stereo models with unprecedented generalization capabilities. Experiments on widely used event stereo datasets support the effectiveness of EventHub and show how the same data distillation mechanism can improve the accuracy of RGB stereo foundation models in challenging conditions such as nighttime scenes.
Figures & tables
Figure 2: Limitations of LiDAR-supervised real-world datasets. Despite their popularity [ 18 , 7 , 84 ] , LiDAR annotations remain sparse (A), poorly capture dynamic scenes (B–C), are prone to reprojection errors (D), and struggle on transparent or reflective surfaces (E).
Figure 3: Framework Overview : We obtain training data through two complementary approaches: (i) Event Data Factory : SVRaster [ 59 ] generates synthetic event stereo pairs and depth labels from sparse RGB images via virtual camera trajectories (left); (ii) Stereo Cross-Modal Distillation : existing RGB stereo models produce proxy depth labels for real event data in calibrated RGB-Event stereo setups (top right). (iii) Both data sources are combined in EventHub to train/adapt event stereo networks (bottom right).
Figure 4: Qualitative examples of events and proxy annotations by EventHub. From top to bottom, examples obtained from NeRF-Stereo [ 63 ] , ScanNet++ [ 75 ] through novel view synthesis, and from DSEC [ 18 ] through cross-modal distillation.
Dataset
MIX 1
MIX 2
MIX 3
MIX 4
NeRF-Stereo [ 63 ]
✓
✓
✓
ScanNet++ [ 75 ]
✓
✓
DSEC [ 18 ]
✓
✓
Table 1: Combinations of datasets used by EventHub. Proxy labels are applied to annotate each dataset.
Training Method
SE-CFF [ 49 ]
EMatch [ 82 ]
E-FoundationStereo
E-StereoAnywhere
Avg Rank
1PE
2PE
3PE
MAE
1PE
2PE
3PE
MAE
1PE
2PE
3PE
MAE
1PE
2PE
3PE
MAE
(A)
Photometric [ 63 ]
88.54
71.73
55.35
7.94
92.31
69.17
44.90
3.37
93.85
73.12
49.82
3.65
92.55
72.25
51.65
4.11
6.94
(B)
EV-SceneFlow [ 17 , 45 ]
66.30
50.18
41.47
3.50
71.64
53.67
42.02
3.56
61.80
48.04
41.68
3.10
64.97
49.54
41.74
3.21
6.06
(C)
MIX 1
45.61
25.15
16.54
1.87
47.17
23.23
13.58
1.70
38.70
15.63
8.83
1.39
35.86
15.13
9.03
1.36
5.00
MIX 2
38.52
18.17
11.02
1.56
41.06
17.81
9.97
1.45
27.20
9.72
5.53
1.04
31.49
12.45
7.32
1.23
4.00
MIX 3
24.73
8.58
5.08
1.01
31.30
11.14
5.90
1.15
20.99
6.82
4.10
0.89
24.35
8.22
4.76
0.99
2.75
Table 2: In-domain experimental results – DSEC [ 18 ] dataset. We train four event stereo models according to different training protocols, not exploiting LiDAR annotations (A,B,C), compared against in-domain training on DSEC with LiDAR labels (D).
Figure 5: Qualitative results on DSEC dataset [ 18 ] . Predictions by E-FoundationStereo trained according to different protocols.
Model
Training Method
M3ED (Day)
M3ED (Night)
M3ED (Indoor)
Avg Rank
1PE
2PE
3PE
MAE
1PE
2PE
3PE
MAE
1PE
2PE
3PE
MAE
SE-CFF [ 49 ]
MIX 3
46.84
25.31
16.99
2.81
58.32
36.07
24.45
3.50
51.03
31.43
23.84
4.52
2.50
MIX 4
35.65
15.18
9.37
1.22
51.57
26.84
15.33
1.70
48.56
27.36
19.33
2.95
1.08
LiDAR (GT)
58.82
41.41
32.93
3.05
58.94
36.78
23.55
2.20
45.33
28.39
21.59
4.48
2.42
EMatch [ 82 ]
MIX 3
86.18
77.61
72.13
40.36
90.02
84.94
82.26
45.41
76.99
65.23
58.98
15.80
3.00
MIX 4
43.99
20.87
12.93
2.23
63.69
38.74
26.38
5.03
58.42
32.16
21.48
3.10
1.00
Table 3: Out-of-domain experimental results – M3ED [ 7 ] dataset. We compare the generalization capability of the four event stereo models trained with MIX 3 and MIX 4 against their counterparts trained using DSEC LiDAR labels.
Model
Training Method
MVSEC (Day)
MVSEC (Night)
MVSEC (Indoor)
Avg Rank
1PE
2PE
3PE
MAE
1PE
2PE
3PE
MAE
1PE
2PE
3PE
MAE
SE-CFF [ 49 ]
MIX 3
77.13
53.87
31.12
3.21
78.19
54.75
31.24
3.64
42.14
24.53
18.04
3.30
2.17
MIX 4
31.99
12.00
6.88
1.11
40.54
19.00
10.13
1.45
29.66
12.34
6.89
1.39
1.00
LiDAR (GT)
97.82
94.85
90.47
6.12
96.89
92.95
87.14
6.07
46.67
26.37
15.43
1.78
2.83
EMatch [ 82 ]
MIX 3
93.80
80.23
59.05
6.00
91.74
75.37
49.51
4.67
58.44
35.05
24.24
3.02
2.08
MIX 4
56.29
21.61
6.67
1.39
68.51
40.48
14.92
1.81
46.03
21.40
12.36
1.93
1.00
Table 4: Out-of-domain experimental results – MVSEC [ 84 ] dataset. We compare the generalization capability of the four event stereo models trained with MIX 3 and MIX 4 against their counterparts trained using DSEC LiDAR labels.
Figure 6: Qualitative results on M3ED [ 7 ] and MVSEC [ 84 ] . Predictions by the four models trained with LiDAR labels or MIX 4.
Model
Training Method
DSEC (Night)
1PE
2PE
3PE
MAE
FoundationStereo (ViT-S)
Author’s Weights [ 69 ]
68.40
47.69
35.80
3.89
MIX 3 (Night)
24.75
8.09
4.25
1.01
FoundationStereo (ViT-L)
Author’s Weights [ 69 ]
30.06
14.87
10.88
1.87
MIX 3 (Night)
25.33
8.48
4.56
1.06
StereoAnywhere (ViT-S)
Author’s Weights [ 6 ]
33.01
14.24
8.93
1.61
Table 5: Experimental results on DSEC night images [ 18 ] – RGB stereo models. Fine-tuning SFMs on proxy labels derived from our event models yields improvements on nighttime images.
Row
λN−mean
λN−med
λasc
λsparse
λDAv2
λMASt3R
PSNR
SSIM( ×100 )
MAE (cm)
δ≤1.25 (%)
1
-
-
-
-
-
-
33.85
87.36
8.81
93.51
2
0.001
0.001
-
-
-
-
33.25
86.77
9.03
92.43
3
0.001
0.001
0.01
-
-
-
33.25
86.77
9.03
92.47
4
0.001
0.001
0.01
0.01
-
-
33.25
86.77
8.99
92.52
5
0.001
0.001
0.01
0.01
0.01
-
33.19
86.73
6.61
96.23
6
0.001
0.001
0.01
0.01
0.01
0.01
26.86
79.64
38.71
67.31
Table 6: Depth regularization ablation. PSNR values are given in decibels. SSIM values are multiplied by a 100 factor. MAE values are reported in centimeters.
Model
PSNR ↑
MAE (cm) ↓
δ≤1.25 (%) ↑
Setup Time (min/scene) ↓
FPS ↑
Depth Anything v3 [ 40 ]
19.19
41.94
53.92
∼ 1
165
Instant-NGP [ 48 ]
29.21
24.68
82.88
∼ 8
5
3DGS [ 31 ]
32.51
22.36
76.23
∼ 20
165
SVRaster [ 59 ]
33.37
6.38
96.44
∼ 20
143
Table 7: Comparison between different NVS engines. SVRaster achieves the best trade-off between rendering quality, setup time and rendering speed.
Confidence
Threshold
MAE (cm)
δ≤1.25 (%)
Density (%)
-
-
6.38
96.44
100.00
CAO
0.35
6.26
96.60
95.45
CVsize
0.75
6.23
96.57
97.42
CAO
0.40
6.22
96.66
92.04
CVsize
0.80
6.15
96.61
95.56
CAO
0.45
6.20
96.72
87.38
Table 8: Confidence threshold study. Comparison between ambient occlusion confidence CAO [ 63 ] and our voxel-based confidence CVsize on ScanNet++ [ 75 ] . MAE values are reported in centimeters.
Training Method
SE-CFF
E-FoundationStereo
1PE ↓
2PE ↓
3PE ↓
MAE ↓
1PE ↓
2PE ↓
3PE ↓
MAE ↓
MIX 3 (SVRaster [ 59 ] )
24.73
8.58
5.08
1.01
20.99
6.82
4.10
0.89
MIX 3 (Depth Anything v3 [ 40 ] )
74.35
47.82
30.63
3.18
71.37
41.01
23.99
2.54
EV-SceneFlow [ 17 , 45 ]
66.30
50.18
41.47
3.50
61.80
48.04
41.68
3.10
EV-(SceneFlow+TartanAir) [ 17 , 45 , 65 ]
57.78
33.01
19.75
2.17
41.86
23.13
16.58
1.76
Table 9: Further in-domain experimental results – DSEC dataset [ 18 ] . On top: comparison between SVRaster and Depth Anything v3 generated data. At the bottom: results by extending the synthetic data used to generate proxy events.
Model
Parameters (M)
FLOPs (G)
Runtime (ms)
Peak Memory (MB)
SE-CFF [ 49 ]
2.97
85.98
46.27
379.13
EMatch [ 82 ]
6.71
501.95
115.20
3090.49
E-StereoAnywhere
39.96
1566.58
219.81
1479.82
E-FoundationStereo
60.09
4445.51
280.11
1525.13
Table 10: Hardware analysis on DSEC dataset [ 18 ] . Measurements taken on a X GPU.
Figure 7: Evaluation on DSEC after different numbers of training steps.
Figure 8: Global trajectory construction.
Figure 9: Qualitative examples of training data generated by EventHub on DSEC [ 18 ] . (a) left color image, (b) left event frame, (c) proxy disparity labels predicted by FoundationStereo [ 69 ] and projected on the event frame.
Figure 10: Qualitative examples of training data generated by EventHub on NeRFStereo [ 63 ] . (a) rendered color image, (b) rendered event frame, (c) rendered depth and (d) confidence (the brighter, the higher the confidence in the estimated depth values), and (e) rendered depth masked according to confidence thresholding.
Figure 11: Qualitative examples of training data generated by EventHub on ScanNet++ [ 75 ] . (a) rendered color image, (b) rendered event frame, (c) rendered depth and (d) confidence, (e) rendered depth masked according to confidence thresholding.
Figure 12: Qualitative results on DSEC [ 18 ] dataset. Predictions by the four models trained with LiDAR labels, MIX 3 or MIX 4.
Figure 13: Qualitative results on M3ED [ 7 ] dataset. Predictions by the four models trained with LiDAR labels, MIX 3 or MIX 4.
Figure 14: Qualitative results on MVSEC [ 84 ] dataset. Predictions by the four models trained with LiDAR labels, MIX 3 or MIX 4.
Figure 15: Improved RGB FoundationStereo at Night. Qualitative comparison on the zurich_city_09_d night sequence. (a) left RGB, (b) prediction by baseline FoundationStereo VIT-L, and (c) its fine-tuned counterpart using proxy labels from E-FoundationStereo VIT-S.
Figure 16: Improved RGB FoundationStereo at Night. Qualitative comparison on the zurich_city_10_b night sequence. (a) left RGB, (b) prediction by baseline FoundationStereo VIT-S, and (c) its fine-tuned counterpart using proxy labels from E-FoundationStereo VIT-S.