Authors: David Serrano-Lozano, Anand Bhattad, Luis Herranz, Jean-François Lalonde, Javier Vazquez-Corral
Organizations: Computer Vision Center Universitat Autònoma de Barcelona · Johns Hopkins University · Universidad Politécnica de Madrid · Université Laval
We present SyncLight, a method to enable consistent, parametric control over light sources across multiple uncalibrated views of a static scene conditioned on a single view. While single-view relighting has advanced significantly, existing generative approaches struggle to maintain the rigorous lighting consistency essential for multi-camera broadcasts, stereoscopic cinema, and virtual production. SyncLight addresses this by enabling precise control over light intensity and color across a multi-view capture of a scene, conditioned on a single reference edit. Our method leverages a multi-view diffusion transformer trained using a latent bridge matching formulation, achieving high-fidelity relighting of the entire image set in a single inference step. To facilitate training, we introduce a large-scale hybrid dataset comprising diverse synthetic environments -- curated from existing sources and newly designed scenes -- alongside high-fidelity, real-world multi-view captures under calibrated illumination. Though trained only on image pairs, SyncLight generalizes zero-shot to an arbitrary number of viewpoints, effectively propagating lighting changes across all views, without requiring camera pose information. SyncLight enables practical relighting workflows for multi-view capture systems.
Figures & tables
Figure 1: Multi-view light editing with SyncLight. Given an uncalibrated multi-view capture of a static scene (1), the user picks a reference view , clicks one or more visible light sources (circle markers), and sets their intensity and chromaticity ; the other views never need to be inspected . SyncLight (2) relights all input views, reference included (3), in a single feedforward pass via latent bridge matching. Per-view light control baselines (bottom-left) hallucinate, lack precise control, and are inconsistent across views. SyncLight is geometrically consistent, needs no camera poses, generalizes to any number of views, and is 10 × faster than current models.
Figure 2: SyncLight formulates multi-view relighting as a conditional flow matching problem in latent space. (Left) Input scenes under source ( xsrc ) and target lighting ground truth ( xtar ) are encoded into latents ( zsrc,ztar ) via a VAE encoder. This is done for both the “Reference” (0) and “Other” (1) views. (Middle) During training, we sample a timestep t and construct a Bridge Matching (BM) interpolant zt . Our backbone, “Multi-View SD”, is conditioned on a user-specified “Lightmap” (encoding color as intensity and chromaticity) derived from the “Reference view”. To enforce consistency, the backbone processes both views simultaneously. (Right) The model predicts the target latents, which are decoded into relit images ( x^T ). The network is optimized using a hybrid objective L combining latent flow matching loss ( Llbm ) with pixel-level reconstruction losses ( Lpix ) for each view to ensure high-fidelity, consistent relighting.
Infinigen
BlenderKit
Real captures
Method
PSNR
SSIM
ΔE00
LPIPS
PSNR
SSIM
ΔE00
LPIPS
PSNR
SSIM
ΔE00
LPIPS
VGGTm
Time (s)
Ref. view
ScribbleLight
10.89
.518
30.67
.382
11.02
.528
29.26
.372
11.78
.483
28.36
.375
-
58.2 ± 1.14
Flux.2-dev
14.23
.672
20.31
.338
16.71
.704
17.22
.291
18.32
.757
14.28
.264
-
55.6 ± 1.02
LightLab*
29.86
.941
3.08
.131
26.38
.907
4.92
.147
28.42
.880
4.61
.199
-
1.17 ± 0.02
GR3EN
25.92
.893
4.38
.158
21.74
.803
8.93
.173
22.31
.782
9.31
.238
-
72.3 ± 3.51
SyncLight
31.32
.950
2.47
.119
27.16
.915
4.02
.134
30.34
.895
3.73
.196
-
-
Table 1: Quantitative multi-view image relighting results on our SyncLight test set. Each section of the table indicates which view is used to compute metrics: the “Reference (Ref.) view” (where edits are specified), “Second (Sec.) view” (another view in the set), and “Additional (Add.) views” (all but the reference view). Best results, achieved by SyncLight in all cases, are highlighted. See text for details on baselines. As SyncLight is always run on more than one image; no inference time is reported for the “Ref. view.” VGGTm (%) measures cross-view consistency against the ground truth (see text); it is undefined for the reference view alone.
Figure 3: Qualitative results showcasing SyncLight’s controllability and generalization. Top-left: precise control over light color, varying the chromaticity of a table lamp across three target hues. Top-right: continuous control over light intensity, from off ( 0.0 ) to fully on ( 1.0 ). Bottom-left: robustness to large camera angle changes, with input views rotated by up to 180∘ relative to the reference. Bottom-right: generalization across diverse scenes and unseen light types. SyncLight produces consistent relighting across all viewpoints.
Figure 4: Results in the Real Split from our dataset. SyncLight relights the images correctly. Flux.2-dev struggles with cross-view consistency, producing visually plausible but geometrically inconsistent results (e.g., the window in the second row). Meanwhile, the LightLab*+LumiNet baseline maintains better consistency by explicitly relighting each view, but fails to propagate lighting effects.
Figure 6
Figure 6: Relighting a scene with seven different views. Top row: Input images. Bottom row: SyncLight results. Note how all the views are consistently modified. We want to emphasize views 2 and 4, in which the lamp turned on is not visible, yet the effects in the scene match those of the other views.
Figure 7: Qualitative results on out-of-distribution images from the RealEstate10K dataset Google Research (2018) . SyncLight outperforms all the other methods, including a per-view informed version of LightLab*, demonstrating that the joint processing of all views is beneficial even for single-light relighting.
Appendix figures & tables15 assets
Supplementary material from the paper’s appendix.
Appendix
Figure 8: Examples from the SyncLight dataset. Samples were selected randomly with random light colors.
Table 10Table 11Table 12
Figure 11: Multi-view relighting examples when training SyncLight without one of the splits of the dataset at a time.
Figure 12: Instructions given to the users for the User Study.
Figure 13: User study results.
Figure 14: SyncLight applied to: (a) video relighting, and (b) novel-view synthesis with radiance fields. Please see the supplementary video on our webpage.
Figure 15: Qualitative results on the SyncLight dataset on the Infinigen (1–2), and BlenderKit (3–4) splits. Real split is shown in the main paper.
Figure 16: Inference time (left) and peak memory (right) of SyncLight as a function of the number of views N on an NVIDIA A40 (BlenderKit, 32 rendered views per scene). Memory grows linearly; compute grows quadratically.
N
PSNR
SSIM
ΔE00
LPIPS
VGGTm
Inf. time (s)
2
30.23
.897
3.56
.197
95.8
1.58 ± 0.02
4
30.40
.904
3.55
.194
94.8
2.17 ± 0.02
6
30.45
.907
3.56
.194
94.9
3.01 ± 0.03
7
30.47
.906
3.56
.192
95.3
3.83 ± 0.03
Appendix
Table 9: Scaling with the number of views N on the Real test split.
Method
Interaction per edited light
Cost per additional view
SyncLight
one click + color + intensity
none
LightLab [ 49 ]
segmentation mask + color + intensity
one mask per view
GR3EN [ 63 ]
segmentation mask + color + intensity
one mask per view + camera poses
LuxRemix [ 42 ]
OLAT harmonization + color + intensity
Plücker embeddings + harmonization
Appendix
Table 10: User input required by each method.
Ours vs. GT
ΔE00 vs. input
Region
PSNR
ΔE00
GT
Ours
Weak edits ( ∣ΔL∣<0.5 )
0–1 r (marker)
30.6
3.12
7.9
8.2
1–2 r
30.9
2.84
3.1
3.3
2–4 r
31.8
2.62
1.6
1.7
> 4 r
32.1
2.71
0.9
1.0
Appendix
Table 11: Local versus global changes on the Real split. Weak and strong edits are separated by the requested lightness change ∣ΔL∣ ; pixels are grouped by their distance to the edited source in multiples of the marker radius r . The last row reports all edits over the full image, as in table 1 .
Figure 17: Additional results on the RealEstate10K dataset.
Figure 18: Additional results on the RealEstate10K dataset