MIRAGE: Metric Inference and Reliability-Aware Gaussian Estimation from Feed-Forward Vision
Authors: Xinzhe Wang, Changjian Jiang, Kaiwen Song, Xudong Li, Kerui Ren, Ran Yi, Lizhuang Ma, Chunhua Shen, +3 more
Organizations: Shanghai Jiao Tong University · Shanghai Artificial Intelligence Laboratory · The University of Hong Kong · University of Science and Technology of China · Fudan University · Zhejiang University · The Chinese University of Hong Kong
Feed-forward 3D priors enable high-quality reconstruction from image streams but often lack reliable metric scale and suffer from long-term trajectory drift. In contrast, LiDAR--inertial estimation provides metrically accurate motion but lacks the image-space consistency needed for high-fidelity reconstruction. We propose MIRAGE, which anchors feed-forward visual geometry to LiDAR--IMU metric motion and regulates online pose corrections according to correspondence support and cross-modal agreement, jointly enabling accurate metric pose estimation and high-fidelity Gaussian reconstruction. Experiments on Oxford Spires, M2DGR and INS show that MIRAGE achieves accurate metric trajectory estimation, outperforming COLMAP, a widely used but computationally expensive reference for vision-only benchmarks. Motivated by the scarcity of long-horizon monocular benchmarks for large-scale indoor reconstruction, we further build a multimodal data-collection platform and use MIRAGE to establish accurate 6-DoF reference trajectories for a new vision-only benchmark. We benchmark recent monocular large-scale reconstruction methods on this dataset, providing a systematic evaluation of their performance in long-horizon indoor scenes.
Figures & tables
Figure 1: We propose MIRAGE , which anchors feed-forward visual geometry to LiDAR–IMU motion through reliability-aware pose refinement. Left: on Oxford Spires Blenheim 02, MIRAGE achieves lower ATE than COLMAP (3.27 vs. 5.50 cm) and higher rendering PSNR than Gaussian-LIC2 (27.82 vs. 21.28 dB). Right: our synchronized multimodal platform supports a long-horizon indoor benchmark with 10 sequences and MIRAGE-established 6-DoF accurate reference trajectories for evaluating vision-only reconstruction. Project Page: MIRAGE-URL .
Figure 2: Pipeline of MIRAGE. We anchor feed-forward visual geometry to LiDAR–IMU motion for metric pose estimation and streaming Gaussian mapping. Local metric constraints support visual pose refinement, while reliability-aware loop correction controls correction magnitude and selectively applies rotation to balance revisit alignment and local motion consistency. The resulting poses drive a triangle-associated Gaussian map. With poses fixed, offline geometry-aware refinement improves scene structure using image residuals and LiDAR support.
Online
Offline
Sequence
EllipseLIO
Fast-LIO- SLAM
Fast- LIVO2
Gaussian- LIC2
LingBot- Map
Ours
Voxel- SLAM
COLMAP
GLUEMAP
Ours+HBA
Latency
0.10
0.12
0.10
0.71
0.18
0.73
0.145
1.85
10.65
0.76
Oxford Spires
Observatory 01
5.74
6.28
3.97
6.41×104
2.46×102
3.43
2.46
6.66
95.79
2.09
Observatory 02
5.23
26.22
6.83
–
3.57×102
3.56
2.14
7.69
75.81
2.07
Keble 02
6.02
37.35
3.01×105
3.08×102
3.27×102
3.60
3.48
4.74
3.30×103
3.66
Table 1: Translational ATE RMSE (cm, ↓ ). Vision-only and metric methods use Sim(3) and SE(3) alignment, respectively. Red/orange mark the best/second-best per sequence, ranked separately for online and offline methods; – denotes failure.
Figure 3: Qualitative trajectory and rendering comparisons. Left: SE(3)-aligned XY trajectories; green boxes show XZ close-ups with equal axis scales. Right: rendering comparisons.
Oxford Spires
M2DGR
INS
Method
Observatory 01
Keble 02
Keble 03
Keble 04
Blenheim 01
Blenheim 02
room_01
room_02
room_03
indoor_sq1
indoor_sq3
indoor_sq4
Gaussian-LIC2
17.91 0.678 0.570
24.26 0.810 0.421
17.49 0.678 0.554
18.72 0.680 0.548
21.76 0.738 0.530
21.28 0.744 0.535
25.15 0.809 0.258
26.67 0.829 0.251
24.60 0.770 0.341
30.09 0.893 0.299
29.24 0.885 0.308
30.45 0.896 0.301
Ours
26.26 0.827 0.308
27.53 0.836 0.325
26.80 0.821 0.344
24.33 0.741 0.390
26.40 0.796 0.396
27.82 0.837 0.357
25.44 0.824 0.255
26.76 0.831 0.252
26.60 0.843 0.249
30.03 0.907 0.294
29.58 0.901 0.306
29.34 0.900 0.307
Our trajectory + Offline 3DGS
26.04 0.801 0.389
26.87 0.823 0.366
25.75 0.804 0.400
23.19 0.711 0.476
24.82 0.749 0.507
26.65 0.787 0.470
26.69 0.865 0.212
27.02 0.847 0.231
26.42 0.850 0.248
26.36 0.831 0.451
27.71 0.855 0.414
25.60 0.832 0.453
Table 2: Held-out rendering quality. Offline 3DGS ( Kerbl et al., 2023 ) uses 30k iterations with MIRAGE’s online poses fixed. Cells list PSNR (dB, ↑ ), SSIM ( ↑ ), and LPIPS ( ↓ ) from top to bottom. Red and orange indicate the best and second-best values per sequence and metric.
(a) Pose estimation
(b) Rendering on M2DGR
Stage
Oxford Spires
M2DGR
INS
Configuration
room_01
room_02
room_03
Tracking
82.363
21.868
43.819
w/o visual †
13.90 / 0.504 / 0.561
13.04 / 0.512 / 0.559
12.89 / 0.489 / 0.577
Local
7.784
1.909
7.055
Streaming
23.28 / 0.746 / 0.339
24.41 / 0.762 / 0.344
24.74 / 0.784 / 0.319
Global
4.529
2.067
5.195
+ Photo. refine
24.96 / 0.811 / 0.272
26.29 / 0.816 / 0.275
26.22 / 0.832 / 0.265
Offline (+HBA)
3.093
1.858
3.513
+ Geo. refine
25.44 / 0.824 / 0.255
26.76 / 0.831 / 0.252
26.60 / 0.843 / 0.249
Table 3: Pose and rendering ablations. (a) Scene-averaged ATE (cm, ↓ ) over all evaluated sequences. (b) PSNR (dB, ↑ ) / SSIM ( ↑ ) / LPIPS ( ↓ ). † : camera poses are obtained solely by interpolating LiDAR–inertial poses and applying calibrated extrinsics; RGB supervision for Gaussian reconstruction is retained.
ATE (m, ↓ )
Offline 3DGS PSNR (dB, ↑ )
Stream PSNR
Sequence
Trajectory length (m)
LingBot- Map
GlueMap
LoGeR
Scal3R
ABot- Recon
MASt3R- SLAM
LingBot- Map
GlueMap
LoGeR
Scal3R
ABot- Recon
MASt3R- SLAM
Ours (reference)
Ours
Laboratory 1
54.57
0.299
0.205
0.927
1.901
0.368
0.491
21.65
26.59
20.74
22.16
23.28
17.54
26.10
27.47
Laboratory 2
61.02
0.430
0.225
0.802
1.102
0.675
0.866
19.93
26.41
19.94
22.11
22.53
14.59
25.02
28.47
Laboratory 3
168.46
9.523
15.851
7.364
1.662
0.930
0.729
18.51
22.60
18.96
21.72
22.06
17.22
23.56
26.74
Dining Area 1
112.69
5.058
15.723
10.616
14.772
0.903
2.168
18.42
22.16
18.76
19.09
21.33
16.16
21.68
26.15
Dining Area 2
64.65
0.316
0.206
1.511
0.350
0.427
0.412
20.11
20.45
19.45
20.50
20.87
16.41
19.84
24.06
Table 4: MIRAGE benchmark. ATE: Sim(3)-aligned translational RMSE against MIRAGE references. Offline 3DGS: held-out PSNR with fixed poses; Ours (reference) uses reference poses. Stream PSNR: MIRAGE after refinement. Red/orange indicate the best/second-best per sequence within the ATE and offline 3DGS groups; – denotes trajectory failure.
Appendix figures & tables8 assets
Supplementary material from the paper’s appendix.
Appendix
Symbol
Definition
W,C,L,B
World, camera, LiDAR, and IMU coordinate frames.
TV,TM,TF
Visual camera poses, metric camera-pose anchors, and fused camera poses.
Sensor acquisition time and corresponding pose-estimate availability time, with ai≥τi .
Appendix
Table 5: Notation and coordinate conventions.
Figure 4: Observation-supported loop correction. Visual evidence is evaluated first, with geometric fallback when no visually supported candidate is selected. Rotation corrections require additional geometric support.
Figure 5: Acquisition platform and dataset overview. Left: the synchronized RGB–LiDAR–IMU platform, sensor layout, and calibrated sensor transforms. Right: RGB images, colored LiDAR maps, MIRAGE reference trajectories, and IMU signals from four representative sequences spanning laboratories, dining areas, corridors, and offices.
Figure 6: Six additional MIRAGE benchmark sequences. Complementing Figure 5 , each row shows RGB images and colored LiDAR maps (left), alongside MIRAGE reference trajectories and IMU signals (right). IMU plots show normalized 20-second excerpts; trajectory grids are illustrative and do not indicate metric scale.
Sequence
# RGB Images
# LiDAR Frames
Duration (min)
Trajectory Length (m)
Laboratory 1
4,112
2,056
3.42
54.57
Laboratory 2
4,470
2,235
3.72
61.02
Laboratory 3
13,336
6,668
11.11
168.46
Dining Area 1
4,430
2,215
3.69
112.69
Dining Area 2
2,126
1,063
1.77
64.65
Dining Area 3
11,667
5,834
9.72
181.52
Appendix
Table 6: Per-sequence acquisition statistics of the MIRAGE benchmark.
Figure 7: Additional qualitative comparisons on Oxford Spires. Rows, from top to bottom: Observatory 01, Keble 02, Keble 03, Keble 04, Blenheim 01, and Blenheim 02. Left: SE(3)-aligned XY trajectories, with green boxes and connectors indicating local views in the labeled planes at equal axis scales. Fast-LIVO2 is off-scale on Keble 02. Right: held-out ground-truth images, Gaussian-LIC2, MIRAGE, and offline 3DGS using MIRAGE trajectories.
Figure 8: Additional qualitative comparisons on M2DGR and INS. Rows, from top to bottom: room_01, room_02, room_03, indoor_sq1, indoor_sq3, and indoor_sq4. Columns and green trajectory insets follow Figure 7 . The arrow highlights a wall artifact in the Gaussian-LIC2 reconstruction of indoor_sq4.
Oxford Spires
M2DGR
INS
Stage
Observatory 01
Observatory 02
Keble 02
Keble 03
Keble 04
Blenheim 01
Blenheim 02
Church 03
room_01
room_02
room_03
indoor sq1
indoor sq2
indoor sq3
indoor sq4
Tracking
69.739
97.263
121.833
77.076
57.736
70.032
149.269
15.960
31.694
20.781
13.128
48.784
63.709
30.351
32.431
Local
4.242
4.695
5.083
7.162
10.725
14.654
14.473
1.239
1.828
1.926
1.971
13.148
5.468
5.172
4.433
Global
3.429
3.559
3.595
7.125
9.611
4.495
3.265
1.154
1.873
2.179
2.148
5.666
5.477
5.198
4.441
Appendix
Table 7: Stage-wise translational ATE RMSE (cm, ↓ ), with independent fixed-scale SE(3) alignment on common within-run timestamps. Tracking denotes saved visual inputs to metric refinement; Local and Global denote the no-loop and corrected camera trajectories.
Metric feed-forward 3D reconstruction for panoramic data remains under-explored due to the lack of large-scale panoramic RGB-D training data. We present Realsee3D, a hybrid dataset of 10K indoor scenes (1K real, 9K synthetic) with 299K panoramic viewpoints and precise metric annotations, and Argus, a feed-forward network trained on it for metric panoramic 3D reconstruction. In the sparse unordered capture setting of Realsee3D, a poorly chosen coordinate anchor can cause global pose drift. Argus addresses this with a learned covisibility module that selects the geometrically optimal reference view to anchor the metric world frame. To further improve multi-task learning, we decompose the bidirectional pixel-to-world mapping into interpretable sub-steps with per-step supervision and cross-coordinate joint constraints, reinforcing geometric consistency across prediction branches. On the Realsee3D benchmark, Argus achieves state-of-the-art metric performance in camera pose estimation, depth estimation, and point cloud reconstruction. Project page: https://argus-paper.realsee.ai.
Xi Li, Linyuan Li, Yan Wu +4
Realsee, China · Quanzhou University of Information Engineering, China
Monocular foundation models provide dense geometry but usually lack a stable metric scale. This paper presents VIDAR, a visual-inertial dense reconstruction framework that couples SVO+IMU odometry with Depth Anything 3. VIDAR uses the visual-inertial front end as a metric anchor: it provides camera poses, scale, and a consistent world frame for aligning dense foundation-model predictions across time. The foundation model then contributes detailed local geometry that is fused into a global reconstruction. We study both pose-conditioned DA3 and a decoupled alignment strategy. On EuRoC, pose injection reduces scale error to about 1% and reaches 0.463 mean [email protected]; the decoupled hybrid improves this to 0.676 without ground-truth poses. Results on EuRoC and TUM RGB-D show that VIDAR is a practical route to metric dense monocular reconstruction.
Diyari Mohammed Salih, Lingxiang Hu, Naima AitOufroukh-Mammar +1
IBISC Laboratory, Université d’Évry Paris-Saclay, Université Paris-Saclay, Évry-Courcouronnes, France.
Recovering metric 3D geometry from monocular images is a fundamental computer vision task, yet current methods remain heavily fragmented by fixed camera model assumptions and inflexible input schemes. We present OmniPoint, a unified framework designed to generalize metric reconstruction across diverse imaging sensors, including pinhole, fisheye, and equirectangular projections, while accommodating varying geometric priors. To overcome projection rigidity, OmniPoint abandons conventional planar depth regression. It instead adopts a decoupled ray and distance representation alongside a decoupled training objective, explicitly separating the camera projection model from the scene structure. To address the severe scarcity of training data for alternative cameras, we introduce a bidirectional augmentation strategy that explicitly bridges labeled perspective data and unlabeled omnidirectional domains in 3D space. Furthermore, to seamlessly integrate optional inputs like camera intrinsics or sparse depth without destabilizing the network through feature distribution shifts, we propose a robust information injection mechanism. This mechanism utilizes learnable input state embeddings to resolve architectural ambiguity and applies vectorized Gaussian smoothing to densify irregular measurements. Extensive experiments demonstrate that OmniPoint achieves state-of-the-art zero-shot performance across multiple benchmarks, establishing a robust new standard for unified monocular 3D reconstruction.
Botao Ye, Marc Pollefeys, Ming-Hsuan Yang +1
Google DeepMind · ETH Zurich · Work done as an intern at Google DeepMind.