Abstract

Large-scale Digital Surface Models (DSMs) can be produced cost-effectively from satellite images via stereo-photogrammetry. However, the resulting 3D maps are often contaminated by noise, outliers, and voids. On the other hand, aerial LiDAR provides high-accuracy elevation measurements at a substantially higher cost. In this work, we study diffusion models conditioned both on photogrammetric DSMs and Pléiades imagery to refine vertically co-registered DSMs. We introduce a modified Stable Diffusion 3 architecture with a pruned text stream and a patch-wise normalization strategy, enabling stable training on LiDAR data and transfer from natural images to elevation maps. Experiments in French cities demonstrate that multimodal conditioning improves elevation accuracy, reducing Dense Urban RMSE from 6.00 to 3.45 m in the in-context cities and from 4.16 to 2.77 m in the held-out city of Bordeaux.

Keywords

Subject

Publication details

DOI
10.3390/rs18193303
Journal
Not available
Open access
Green open access

Cite this article

APA 7

Lorentz, A., May, S., Bellet, V., Derksen, D., & Nespoulous, B. (2026). Enhancing Photogrammetric Digital Surface Models with Pretrained Diffusion Models and Multimodal Conditioning. https://doi.org/10.3390/rs18193303

MLA 9

Lorentz, Antoine, et al. "Enhancing Photogrammetric Digital Surface Models with Pretrained Diffusion Models and Multimodal Conditioning." https://doi.org/10.3390/rs18193303.

Chicago (author–date)

Lorentz, Antoine, Stéphane May, Valentine Bellet, Dawa Derksen, and Bastien Nespoulous. 2026. "Enhancing Photogrammetric Digital Surface Models with Pretrained Diffusion Models and Multimodal Conditioning." https://doi.org/10.3390/rs18193303.

Harvard

Lorentz, A., May, S., Bellet, V., Derksen, D. and Nespoulous, B. (2026) 'Enhancing Photogrammetric Digital Surface Models with Pretrained Diffusion Models and Multimodal Conditioning', doi:10.3390/rs18193303.

Vancouver

Lorentz A, May S, Bellet V, Derksen D, Nespoulous B. Enhancing Photogrammetric Digital Surface Models with Pretrained Diffusion Models and Multimodal Conditioning. doi:10.3390/rs18193303

IEEE

A. Lorentz, S. May, V. Bellet, D. Derksen, and B. Nespoulous, "Enhancing Photogrammetric Digital Surface Models with Pretrained Diffusion Models and Multimodal Conditioning," doi: 10.3390/rs18193303.