wildflow/soneva-corals

Soneva Coral Reef Time-Series Photogrammetry

The Soneva Conservation and Sustainability Maldives team and Wildflow are sharing an open time-series 3D photogrammetry dataset from coral restoration and monitoring plots in the Maldives.

Right now it is hard to find high-quality open time-series 3D photogrammetry data of coral reefs. Coral reefs support over a quarter of all marine life and up to a billion people, yet they are disappearing fast. A lot of people are working hard to protect and restore them; we hope open access to real reef data helps more teams build useful tools, compare methods, and learn from each other.

This release contains 23 surveys across 6 coral reef plots, captured between 2025-06-02 and 2026-03-04 following the protocol. It includes 22,422 raw GoPro images plus processed reconstruction assets: COLMAP cameras and poses, dense point clouds, orthomosaic PMTiles, coordinate transforms, and multi-LOD Gaussian splat PLYs.

The surveys were co-registered so individual coral colonies can be followed through time. You can use the data for coral reef monitoring, time-series 3D reconstruction, SLAM, semantic segmentation, species identification, AR/VR, education, games, visualisation, or anything else that benefits from real underwater 3D data.

You can also explore the surveys in the browser-based viewer: wildflow.ai/soneva.

License

This dataset is licensed under CC-BY-4.0. You can use it for research, education, and commercial work as long as attribution is provided.

Structure

Each survey is stored as:

maldives_soneva_<plot>_<yyyymmdd>/
├── raw/                         # Raw GoPro images
├── colmap/                      # COLMAP reconstruction files
│   ├── cameras.bin
│   ├── images.bin
│   ├── points3D.bin
│   └── image_mapping.csv        # Raw image path to COLMAP image mapping
├── ortho/
│   ├── ortho.pmtiles            # Browser/GIS-friendly tiled orthomosaic
│   └── world_to_pixel.json      # Coordinate transform metadata
├── splats/
│   └── ply/
│       ├── lod0.ply
│       ├── lod1.ply
│       ├── lod2.ply
│       ├── lod3.ply
│       └── lod4.ply
└── point_cloud.ply              # Dense exported point cloud, XYZ only

metadata.json                    # Survey-level metadata

Metadata

metadata.json contains per-survey metadata:

• capture date
• scale bar length and measured scale bar depths
• SW corner coordinates where available from the source spreadsheet
• raw image counts and sizes
• reference scalebar endpoint projections for the 6 base surveys where alignment annotations are available

Scale bars are 0.5 m long. Projection references use survey-relative raw image paths and COLMAP image IDs, for example:

{
  "image": "raw/10.07.25 RHS/G0016051.JPG",
  "colmap_image_id": 494,
  "pixel_x": 2403.375,
  "pixel_y": 2996.55688
}

Survey Summary

Plot	Surveys
HB	4
OOTBM	3
OOTBR	4
OOTSL1	4
OOTSR2	4
OOTSR3	4
Total	23

Available Assets

Asset	Notes
Raw images	22,422 images, ~67 GB
COLMAP	cameras.bin, images.bin, points3D.bin, image_mapping.csv
Orthomosaics	PMTiles plus world_to_pixel.json
Dense point clouds	One XYZ-only point_cloud.ply per survey
Gaussian splat PLYs	5 LODs per survey

Contributors

This dataset was made possible by the Soneva Conservation and Sustainability Maldives team:

• Ben Yuen
• Ayla Kroon
• Tom Freer
• Ashley Wallis
• the Soneva CSM coral interns
• Johanna Leonhardt

Processed and published with support from Wildflow.

For questions about the dataset, contact Sergei Nozdrenkov at sergei@wildflow.ai or Ben Yuen at benedict@soneva.com.

Cite

@misc{wildflow_soneva_corals_2026,
  author       = {Ben Yuen and Ayla Kroon and Tom Freer and Ashley Wallis and Johanna Leonhardt and Wildflow},
  title        = {Soneva CSM Coral Reef Time-Series Photogrammetry Dataset},
  year         = {2026},
  url          = {https://huggingface.co/datasets/wildflow/soneva-corals},
  publisher    = {Hugging Face}
}

Links:

• huggingface.co/datasets/wildflow/soneva-corals -- this dataset
• wildflow.ai/soneva -- explore in the browser
• instagram.com/soneva.coral -- Soneva CSM
• protocol -- how to collect the data
• Announcement in LinkedIn, Twitter/X, BlueSky.