GroundControl: Satellite-Conditioned Multi-View Diffusion for Reconstruction-Free Novel View Synthesis

WACV 2027
Paper arXiv Code
GroundControl teaser comparing SEVA with satellite-conditioned novel-view synthesis

TL;DR: We introduce GroundControl, a reconstruction-free multi-view diffusion model that conditions on satellite imagery to synthesize street-level novel views that follow the satellite scene layout.

Generating left and right views from front view alone (low overlap) on Metropolis driving scenes. Ground truth (top), SEVA (middle), GroundControl (bottom); the center column is the front input. Conditioned on a satellite image, GroundControl produces higher-quality views that follow the satellite scene layout.

Abstract


Multi-view or video diffusion models have recently emerged as state-of-the-art approaches for novel-view synthesis from sparse image collections. While they can produce high-quality images, they tend to hallucinate unrealistic spatial layouts when synthesizing views outside the input views (scene extrapolation). We propose to address this challenge for outdoor scenes by using satellite images as an additional information source to condition the multi-view generative model. We introduce a new satellite-conditioned multi-view diffusion model that combines conditioning from a satellite image and street-level input images when generating novel views. Our cross-attention based conditioning allows us to retain pretrained multi-view diffusion priors to generate seamless, realistic novel views from a handful of source views, while also adhering to the scene layout as seen from satellite images. Our model does not use 3D scene reconstruction, and only relies on posed street and satellite views. Our experiments on outdoor datasets show that our model is better than both satellite-conditioned or street-view conditioned baselines on novel-view synthesis, especially on highly challenging cases where generated views have little to no overlap with source views.

Method


GroundControl is a satellite-conditioned multi-view diffusion model for outdoor novel-view synthesis. Given sparse posed street-level photos and a single satellite image, it generates photorealistic target views that follow the satellite layout without reconstructing a 3D scene, estimating a height map, or requiring pixel-accurate 6DoF ground–satellite alignment. The model needs only metric relative poses between cameras and a coarse 3DoF (X, Y, heading) satellite alignment.

Overview of the GroundControl architecture

GroundControl adds ray-guided satellite attention to a frozen SEVA multi-view diffusion backbone. A DINOv3 encoder provides satellite features; only the new cross-attention blocks are trained.

Ray-guided cross-attention

Satellite images differ sharply from street-level photos in both appearance and viewpoint, so letting noisy diffusion tokens attend to the full top-down image is hard to learn. GroundControl instead uses ray-guided cross-attention: each street-view token attends only to satellite tokens along its 3D ray, with Plücker ray and timestep embeddings added to the query.

Ray-guided cross-attention attends only along the camera ray in the satellite image

Ray-guided cross-attention restricts each street-view token to satellite tokens along its 3D ray, rather than attending to the full top-down image.

These layers are added as residual blocks on a frozen SEVA backbone and zero-initialized, so the pretrained multi-view generative prior is preserved at the start of training.

Dual classifier-free guidance

At inference we use dual classifier-free guidance, with separate scales for input-view and satellite conditioning. A single CFG coefficient would couple the two: turning up satellite adherence would also over-steer street-level appearance. Dual CFG lets us strengthen layout fidelity independently, and trade photorealism for satellite adherence depending on the setting.

Comparisons


Satellite conditioning improves layout fidelity when synthesizing views with little overlap from the inputs.

On driving data, GroundControl recovers buildings, roads, and street furniture that a street-view-only diffusion model invents or omits. Each row below shows a satellite crop (input cameras in red, the shown target in green), an example input view, the ground-truth target, then predictions from GroundControl, SEVA, and Sat2Density.

Satellite view Example input Ground truth Ours SEVA Sat2Density
Metropolis
Metropolis satellite view with camera frustums Metropolis input ground view Metropolis ground-truth target view GroundControl Metropolis prediction SEVA Metropolis prediction Sat2Density Metropolis prediction
Metropolis satellite view with camera frustums Metropolis input ground view Metropolis ground-truth target view GroundControl Metropolis prediction SEVA Metropolis prediction Sat2Density Metropolis prediction
nuScenes
nuScenes satellite view with camera frustums nuScenes input ground view nuScenes ground-truth target view GroundControl nuScenes prediction SEVA nuScenes prediction Sat2Density nuScenes prediction
nuScenes satellite view with camera frustums nuScenes input ground view nuScenes ground-truth target view GroundControl nuScenes prediction SEVA nuScenes prediction Sat2Density nuScenes prediction

In-distribution results on Metropolis and nuScenes. Sat2Density panoramas are cropped to the target pinhole FOV.

The same satellite prior also helps on DL3DV, which is outside our driving-centric training distribution. These results use the geolocalized outdoor split from Cross-View Splatter. Sparse handheld captures still leave background structure underconstrained; GroundControl uses the top-down image to place buildings and open space more faithfully.

Satellite view Example input Ground truth Ours SEVA Sat2Density
DL3DV satellite view with camera frustums DL3DV input ground view DL3DV ground-truth target view GroundControl DL3DV prediction SEVA DL3DV prediction Sat2Density DL3DV prediction
DL3DV satellite view with camera frustums DL3DV input ground view DL3DV ground-truth target view GroundControl DL3DV prediction SEVA DL3DV prediction Sat2Density DL3DV prediction

Out-of-distribution results on the geolocalized DL3DV split from Cross-View Splatter.

Multi-view comparison of SEVA, GroundControl, and ground truth on a driving sequence

Multi-view extrapolation on a driving sequence. GroundControl follows the true building layout across frames, while SEVA hallucinates inconsistent facades.

Unconditional SEVA extrapolation versus satellite-conditioned GroundControl samples

Without satellite conditioning, SEVA samples diverge into different (often incorrect) layouts. GroundControl’s samples stay consistent with the satellite geometry while still varying in appearance.

Results


In-distribution. We evaluate on held-out nuScenes (150 scenes) and Metropolis (36 scenes) splits that match our training domain. SEVA produces plausible street views from its multi-view prior but weaker layout adherence. Sat2Density, which uses satellite imagery alone, struggles to recover street-level appearance. GroundControl improves both image quality and semantic layout, with the largest gains on Metropolis, where target cameras have very little overlap with the inputs.

nuScenes PSNR ↑ SSIM ↑ LPIPS ↓ IoUroad ↑ IoUbdg ↑
SEVA 11.330.3080.6160.4250.182
Sat2Density 10.680.3010.714——
GroundControl 11.88 0.331 0.619 0.437 0.200
Metropolis PSNR ↑ SSIM ↑ LPIPS ↓ IoUroad ↑ IoUbdg ↑
SEVA 10.880.3150.5860.5810.291
Sat2Density 9.070.3460.743——
GroundControl 12.81 0.401 0.547 0.630 0.372

Sparse-view novel-view synthesis on in-distribution driving datasets. Semantic IoU uses SAM3 road and building masks.

Out-of-distribution. On 39 geolocalized outdoor DL3DV sequences from Cross-View Splatter (3 input views, 37 target views), GroundControl generalizes despite being trained mainly on driving data. It improves PSNR, SSIM, and multi-view consistency over SEVA, while remaining comparable in perceptual metrics. While DL3DV has more input-target view overlap than Metropolis, GroundControl still improves multi-view consistency (lower TSED).

Method PSNR ↑ SSIM ↑ LPIPS ↓ TSED ↓ % Consistent ↑
Sat2Density 10.200.2320.768—0.0
ViewCrafter* 13.350.2600.5473845.62.0
SEVA 14.910.3600.40722.7563.0
GroundControl (Ours) 15.17 0.372 0.414 18.35 65.6

DL3DV benchmark. *ViewCrafter uses a continuous trajectory and a different input–target split.

Ablating design choices.

Ablations on the Metropolis dataset show that simply treating the satellite image as another input camera view is not enough: a specialized satellite encoder is required. The use of ray-guided cross-attention, ray and timestep query embeddings, and encoder-side conditioning all matter for good satellite-conditioned generation.

Dual CFG adds a separate coefficient for satellite conditioning vs. input-image conditioning, and lets us trade perceptual quality for satellite adherence.

Variant PSNR ↑ DINO ↓ SEG ↑
Satellite as input view 11.315.860.558
W/o ray-guided CA 11.685.580.573
W/o ray & timestep embeds 11.375.310.579
UNet decoder conditioning 11.295.400.572
W/o dual CFG 12.715.140.608
Ours 12.81 5.25 0.605

Ablation study on the Metropolis dataset.

Acknowledgements


We thank Filippo Aleotti, Gabriel Brostow, and Alan Paul for their support and insightful feedback, and Jinghao Zhou for clarifications on SEVA.

BibTeX


If you find this work useful for your research, please consider citing our paper:

@inproceedings{krishnan2027groundcontrol,
    title     = {{GroundControl: Satellite-Conditioned Multi-View Diffusion for Reconstruction-Free Novel View Synthesis}},
    author    = {Krishnan, Akshay and Turkulainen, Matias and Wynn, Jamie and Qureshi, Zawar and Sayed, Mohamed and Garcia-Hernando, Guillermo and Vicente, Sara and Hays, James and Firman, Michael and Turmukhambetov, Daniyar},
    booktitle = {Proceedings of the IEEE/CVF Winter Conference on Applications of Computer Vision (WACV)},
    year      = {2027}
}