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MatchGeo Dataset — Version 1.1

1. Dataset Overview

Attribute Details
Title MatchGeo: Multi-region Digital Elevation Model Dataset for Local Feature Matching
Version 1.1
Release Date 2026-05-11
Authors / Creators Correa, S. P. L. P.; Pazini Pedro, D. F.; Oliveira, H. N.; Belton, D.; Ivánová, I.; Santos, A. de Paula
Contact sabrina.correa@ufv.br
Persistent Identifier (DOI) 10.5281/zenodo.21229785
Keywords digital elevation model, DEM, DSM, local feature matching, geospatial dataset, urban terrain, cross-domain matching, computer vision, GeoTIFF, LiDAR, photogrammetry, Structure-from-Motion, satellite stereophotogrammetry
Related Publication In preparation
Repository Zenodo · Hugging Face

2. Description

MatchGeo is a curated, multi-region Digital Elevation Model (DEM) dataset designed for training and benchmarking local feature matching algorithms in urban and natural terrain analysis. It aggregates high-resolution elevation data from 13 distinct environments across 6 continents to support research in cross-domain local feature detection and matching under varying acquisition methods, climates, terrain types, and urban morphologies.

The dataset provides standardized 256x256 pixel GeoTIFF patches with handcrafted ground truth annotations for two cities, enabling systematic evaluation of both intra-region and inter-region model generalization.

Geographic & Temporal Scope

Region Country Temporal Coverage Spatial Coverage Terrain Type
Antarctic Peninsula (ATA_MV) Antarctica 2009–2024 Peninsula Polar, ice
São Paulo (BRA_SP) Brazil 2020 Municipal (1,544 km²) Tropical, urban
Wutai Shan (CHN_WS) China 2021 Regional Mountainous
El Hierro (ESP_EH) Canary Islands (Spain) 2022–2025 Regional Volcanic, coastal
Lahti Lake (FIN_LM) Finland 2020–2026 Regional Temperate, country
Bonn (GER_BN) Germany 2016–2018 City limits Temperate, country
Sinabung Volcano (IDN_SV) Indonesia 2018 16.07 km² Volcanic, tropical
Almaty City (KAZ_AC) Kazakhstan 2017 304.28 km² Semi-arid, urban
Wadi Al-Akhdar (KSA_WA) Saudi Arabia 2016 1,200 km² Desert, graben
Hebron Fault (NAM_HF) Namibia 2017 Regional Arid, fault zone
Kapiti Coast (NZL_KP) New Zealand 2010–2025 Regional Coastal, temperate, country
Tarlac (PHL_TA) Philippines 2014–2017 Regional Tropical, flat
Grand Canyon (USA_GC) United States 2020–2026 Regional Desert, canyon

Purpose & Use Cases

  • Training and benchmarking local feature detectors and descriptors on geospatial elevation data
  • Cross-domain generalization studies (LiDAR vs. photogrammetry vs. satellite, temperate vs. tropical vs. desert)
  • Urban terrain analysis and change detection
  • Evaluation of matching robustness across sensor modalities and terrain types
  • Benchmarking for computer vision models on non-RGB data

3. Content & Schema

3.1 Files Included

Filename / Folder Description Approx. Size
data/ATA_MV/ Antarctic Peninsula tiles + metadata 138.3 MB
data/BRA_SP/ São Paulo tiles + annotations + metadata 105.34 MB
data/CHN_WS/ Wutai Shan tiles + metadata 206.08 MB
data/ESP_EH/ El Hierro tiles + metadata 422.49 MB
data/FIN_LM/ Lahti Lake tiles + metadata 45.97 MB
data/GER_BN/ Bonn tiles + annotations + metadata 333.24 MB
data/IDN_SV/ Sinabung Volcano tiles + metadata 34.98 MB
data/KAZ_AC/ Almaty City tiles + metadata 128.00 MB
data/KSA_WA/ Wadi Al-Akhdar tiles + metadata 556.85 MB
data/NAM_HF/ Hebron Fault tiles + metadata 115.24 MB
data/NZL_KP/ Kapiti Coast tiles + metadata 362.23 MB
data/PHL_TA/ Tarlac tiles + metadata 64.10 MB
data/USA_GC/ Grand Canyon tiles + metadata 138.27 MB
splits/ Train / validation / test split manifests (CSV) 1.6 MB
manifest.json Central machine-readable catalog (JSON-LD) 7.2 KB
README.md High-level project documentation 12.5 KB
DATASET_DESCRIPTION.md This file 126.0 KB
LICENSE Full CC BY 4.0 legal text 14.2 KB

3.2 Per-region File Structure

Each region folder follows this structure:

<REGION_ID>/
├── <REGION_ID>.tif                  # Merged DEM (BigTIFF, tiled, DEFLATE)
├── <REGION_ID>_extent.geojson       # Bounding polygon of full coverage
├── <REGION_ID>_tiles.geojson        # Tile index (grid of all 256x256 patches)
├── metadata/
│   └── <REGION_ID>_metadata.json    # ISO 19115-2 + OGC 23-008r3 metadata
├── annotations/                     # Only for labelled cities (BRA_SP, GER_BN)
│   └── <REGION_ID>_###_###.json     # Keypoint annotations per tile
└── tiles/
    └── <REGION_ID>_###_###.tif      # 256x256 pixel patches

3.3 Data Dictionary

Variable / Field Data Type Description Units / Format Nullable Example
tile_id string Unique identifier for each 256x256 patch — No GER_BN_001_010
region string Source region code — No GER_BN
geometry GeoTIFF raster Elevation patch 256x256 px, float32 No —
crs string Coordinate reference system EPSG code No EPSG:25832
resolution float Ground sample distance meters No 1.0
acquisition_method string Data acquisition technique — No airborne_lidar
acquisition_year integer Year of data capture year No 2017
elevation_min float Minimum elevation in patch meters Yes 42.3
elevation_max float Maximum elevation in patch meters Yes 156.8
elevation_mean float Mean elevation in patch meters Yes 98.4
elevation_std float Standard deviation of elevation meters Yes 12.1
annotated boolean Whether patch has handcrafted ground truth — No true
n_annotations integer Number of verified point annotations in patch count Yes 127
split string Dataset split assignment — No train
difficulty string Difficulty tag for stratification — Yes easy

4. Methodology & Provenance

4.1 Data Sources

All raw data were obtained from open municipal, national, or research portals and are redistributed under terms compatible with CC BY 4.0.

City Source Dataset Provider Method Resolution Year CRS License / Terms
ATA_MV REMA Polar Geospatial Center / University of Minnesota Satellite stereophotogrammetry 1.0 m 2009–2024 EPSG:3031 CC BY 4.0
BRA_SP GeoSampa MDS 2020 Prefeitura de São Paulo (PMSP) / SMUL / GEOINFO Airborne LiDAR (Optech ORION H300) 0.5 m 2020 EPSG:31983 Open municipal data
CHN_WS Wutai Shan / Yingwang Shan 2021 Zhou, C. / OpenTopography UAV SfM (DJI Phantom 4) 1.0 m 2021 EPSG:32649 OpenTopography terms
ESP_EH PNOA-LiDAR 3ª Cobertura CNIG / Instituto Geográfico Nacional Airborne LiDAR 0.5 m 2022–2025 EPSG:3040 CC BY 4.0
FIN_LM Elevation Model 2 m Maanmittauslaitos (NLS Finland) Airborne LiDAR + photogrammetry 2.0 m 2020–2026 EPSG:3067 CC BY 4.0
GER_BN Digitales Oberflächenmodell (DOM) Geobasis NRW / Bezirksregierung Köln Airborne LiDAR 1.0 m 2016–2018 EPSG:25832 Open data
IDN_SV Sinabung Volcano 2018 Carr, B. / OpenTopography UAS SfM (DJI Matrice 210) 0.87 m 2018 EPSG:32647 OpenTopography terms
KAZ_AC Almaty City 2017 Amey et al. / OpenTopography Pleiades Tristereo 1.0 m 2017 EPSG:32643 OpenTopography terms
KSA_WA Wadi-al-Akhdar 2016 Matthieu et al. / OpenTopography SPOT 6 Stereo 1.6 m 2016 EPSG:32637 OpenTopography terms
NAM_HF Hebron Fault 2017 Salomon et al. / UCT / OpenTopography WorldView-3 Stereo 0.53 m 2017 EPSG:32733 OpenTopography terms
NZL_KP NZ LiDAR 1m DEM LINZ Airborne LiDAR 1.0 m 2010–2025 EPSG:2193 CC BY 4.0
PHL_TA LiPAD UP Diliman TCAGP / DREAM / DOST Airborne LiDAR 1.0 m 2014–2017 EPSG:32651 Open data
USA_GC USGS 3DEP DEM U.S. Geological Survey LiDAR 0.5 m 2020–2026 EPSG:6341 Public Domain

4.2 Processing Pipeline

All cities were processed through a standardized PDAL pipeline with region-specific adaptations:

  1. Acquisition & Download — Raw data retrieved from source portals in native CRS and resolution.
  2. Preprocessing (region-specific):
    • BRA_SP: Ground classification via filters.smf (scalar=1.25, slope=0.15, threshold=0.5, window=16.0)
    • CHN_WS: Noise removal (filters.range Classification![7:7]) + statistical outlier removal (mean_k=6, multiplier=2.0)
    • IDN_SV, KSA_WA, NAM_HF: Statistical outlier removal (mean_k=6, multiplier=2.0)
    • Others: Direct rasterization
  3. Rasterization — PDAL writers.gdal with:
    • output_type: max (DSM: highest point per cell)
    • data_type: float32
    • nodata: -9999
    • gdalopts: COMPRESS=DEFLATE|TILED=YES|BIGTIFF=YES
    • resolution: City-specific (see table above)
  4. Patch Extraction — Non-overlapping 256x256 pixel patches extracted using a regular grid (no resampling).
  5. Quality Control — Outlier removal based on elevation range checks, CRS validation, and visual inspection.
  6. Annotation (BRA_SP, GER_BN) — Handcrafted point-level annotations in normalized coordinates.
  7. Stratified Splitting — 80% train / 10% validation / 10% test (planned; to be stratified by region and difficulty).
  8. Packaging & Metadata — Per-region ISO 19115-2 metadata; central JSON-LD manifest; archived on Zenodo with DOI.

4.3 Software & Tools

  • Python 3.10.20
  • PDAL 2.6.0 (point cloud processing)
  • GDAL / rasterio (geospatial I/O and reprojection)
  • NumPy / pandas (tabular metadata management)
  • Custom annotation and patch-generation scripts

5. Access & Licensing

5.1 Availability

Repository URL Access Type
Zenodo (Primary) https://doi.org/10.5281/zenodo.21229785 Open, DOI-backed, permanent
Hugging Face Datasets https://huggingface.co/datasets/paeslemesa/matchgeo Open, streaming loader available
  • Total Size: ~12.5 GB
  • File Formats: Cloud Optimized GeoTIFF - COG (.tif), GeoJSON (.geojson), metadata JSON, split manifests CSV
  • Access Type: Open access, no registration required

5.2 License

This dataset is released under the Creative Commons Attribution 4.0 International License (CC BY 4.0).

You are free to:

  • Share — copy and redistribute the material in any medium or format
  • Adapt — remix, transform, and build upon the material for any purpose, even commercially

Under the following terms:

  • Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made.

The full legal text is provided in the LICENSE file and at https://creativecommons.org/licenses/by/4.0/legalcode.

5.3 Terms of Use & Source Attribution

When using this dataset, your publication or product must include:

  1. Dataset citation (see Section 8: Citation)
  2. Original source acknowledgments (per region):
    • ATA_MV: Data derived from REMA © Polar Geospatial Center / University of Minnesota
    • BRA_SP: Data derived from GeoSampa © Prefeitura de São Paulo
    • CHN_WS: Data derived from OpenTopography dataset by Zhou, C. (DOI: 10.5069/G98C9TGT)
    • ESP_EH: Data derived from PNOA-LiDAR © CNIG / Instituto Geográfico Nacional
    • FIN_LM: Data derived from Maanmittauslaitos © National Land Survey of Finland
    • GER_BN: Data derived from Geobasis NRW © Bezirksregierung Köln
    • IDN_SV: Data derived from OpenTopography dataset by Carr, B. (DOI: 10.5069/G8988568)
    • KAZ_AC: Data derived from OpenTopography dataset by Amey et al. (DOI: 10.5069/G9H41PMP)
    • KSA_WA: Data derived from OpenTopography dataset by Matthieu et al. (DOI: 10.5069/G9V40SDZ)
    • NAM_HF: Data derived from OpenTopography dataset by Salomon et al. (DOI: 10.5069/G9W957BC)
    • NZL_KP: Data derived from LINZ © Land Information New Zealand
    • PHL_TA: Data derived from LiPAD © UP Diliman TCAGP / DREAM Program
    • USA_GC: Data derived from USGS 3DEP © U.S. Geological Survey

6. Interoperability & Technical Details

6.1 Standards & Formats

Aspect Standard / Value
Raster format Cloud Optimized GeoTIFF (BigTIFF variant, OGC 23-008r3 compliant)
Internal tiling 256 × 256 pixels
Pixel depth Float32
Patch dimensions 256 × 256 pixels
Coordinate systems Region-specific UTM (see Section 4.1)
Metadata standard ISO 19115-2 + OGC 23-008r3
Encoding UTF-8 for all text and tabular files
Compression DEFLATE
NoData value -9999

6.2 OGC GeoTIFF Compliance (23-008r3)

All GeoTIFFs comply with OGC 23-008r3 and contain the following required keys:

Key Status Source
GTModelTypeGeoKey ✅ PDAL override_srs
GTRasterTypeGeoKey ✅ GDAL default (PixelIsArea)
ProjectedCSTypeGeoKey ✅ EPSG code embedded
GeogGeodeticDatumGeoKey ✅ Derived from EPSG
GeogAngularUnitsGeoKey ✅ Degree (default)
ProjLinearUnitsGeoKey ✅ Meter (default)
PixelScale ✅ GDAL writer
TiePoint ✅ Upper-left corner coordinate
BigTIFF ✅ BIGTIFF=YES
Tiled ✅ TILED=YES
Compression ✅ COMPRESS=DEFLATE
NoData ✅ nodata=-9999

Note on vertical CRS: The GeoTIFFs encode 2D projected CRS (EPSG codes) with elevation as pixel values. A vertical CRS is not explicitly embedded in the GeoTIFF GeoKeys; vertical datum information is documented in per-region metadata.json files.

6.3 Controlled Vocabularies

  • GCMD Keywords: EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION > DIGITAL ELEVATION/TERRAIN MODEL (DEM)
  • ISO Topic Category: elevation
  • INSPIRE Theme: Elevation

6.4 Data Splits

Split Proportion Stratification
Train 80% By region and difficulty
Validation 10% By region and difficulty
Test 10% By region and difficulty

Explicit intra-region and inter-region test subsets are planned for future releases.


7. Quality Assurance & Known Limitations

7.1 Validation

  • Bonn annotations were verified by multiple annotators.
  • Elevation ranges were cross-checked against known region topographies.
  • CRS consistency was validated using GDALinfo and automated assertions.

7.2 Known Biases & Limitations

Issue Description Mitigation / Status
Geographic bias Dense annotation only in GER_BN and BRA_SP; others unlabelled v1.1 separates labelled/unlabelled; future releases will add annotations
Temporal mismatch Data spans 2009–2026 across cities Documented; users should account for temporal drift
Sensor heterogeneity LiDAR, photogrammetry, SfM, satellite stereo — different noise characteristics Explicitly treated as cross-domain challenge
Resolution heterogeneity Native resolutions range from 0.5 m to 2.0 m
Missing data Water bodies, ocean excluded; NoData=-9999 Documented in per-tile metadata
ATA_MV uncertainty Antarctica data from REMA satellite stereophotogrammetry Marked for verification
CHN_WS CRS discrepancy BibTeX says EPSG:32649; user previously mentioned EPSG:32648 To be verified from actual file
Vertical CRS No explicit vertical GeoKey in GeoTIFFs; elevations are source-dependent (orthometric or ellipsoidal) Documented in per-region metadata.json

8. Citation

If you use this dataset in your research, please cite:

@dataset{correa_2026_matchgeo,
  author       = {Correa, S. P. L. P. and Pazini Pedro, D. F. and Oliveira, H. N. and Belton, D. and Ivánová, I. and Santos, A. de Paula},
  title        = {{MatchGeo: Digital Elevation Model Dataset for Local Feature Matching}},
  year         = 2026,
  publisher    = {Zenodo},
  version      = {1.1},
  doi          = {10.5281/zenodo.21229785},
  url          = {https://doi.org/10.5281/zenodo.21229785},
  note         = {Contains data derived from REMA, GeoSampa, OpenTopography, CNIG, Maanmittauslaitos, Geobasis NRW, LINZ, LiPAD, and USGS 3DEP}
}

Plain text citation:
Correa, S. P. L. P., Pazini Pedro, D. F., Oliveira, H. N., Belton, D., Ivánová, I., & Santos, A. de Paula. (2026). MatchGeo: Digital Elevation Model Dataset for Local Feature Matching (Version 1.1) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.21229785

Source Dataset Citations

When using specific cities, also cite the original sources:

% BRA_SP
@misc{datasetgeosampa,
  author = {{Prefeitura do Munic{'i}pio de S{\~a}o Paulo (PMSP)}},
  title = {{Nuvem de Pontos {MDS} 2020}},
  year = {2020},
  publisher = {GeoSampa},
  url = {https://geosampa.prefeitura.sp.gov.br/}
}

% CHN_WS
@misc{datasetchinayingwang2021,
  author = {Zhou, C.},
  title = {High Resolution Topography of {Wutai Shan} and {Yingwang Shan}, China, 2021},
  year = {2023},
  publisher = {OpenTopography},
  doi = {10.5069/G98C9TGT}
}

% ESP_EH
@misc{datasetspain,
  author = {{Centro Nacional de Informaci{'o}n Geogr{'a}fica (CNIG)}},
  title = {{PNOA-LiDAR --- 3{\textordfeminine} Cobertura (2022--2025)}},
  year = {2022--2025},
  url = {https://centrodedescargas.cnig.es/CentroDescargas/lidar-tercera-cobertura}
}

% FIN_LM
@misc{datasetfinland,
  author = {{Maanmittauslaitos --- National Land Survey of Finland}},
  title = {{Korkeusmalli 2 m / Elevation Model 2 m}},
  year = {2026},
  url = {https://www.maanmittauslaitos.fi/en/maps-and-spatial-data/datasets-and-interfaces/product-descriptions/elevation-model-2-m}
}

% GER_BN
@misc{datasetgermany,
  author = {{Geobasis NRW --- Bezirksregierung K{\"o}ln}},
  title = {{Digitales Oberfl{\"a}chenmodell ({DOM})}},
  year = {2024},
  url = {https://www.bezreg-koeln.nrw.de/geobasis-nrw/produkte-und-dienste/hoehenmodelle/digitale-oberflaechenmodelle/digitales}
}

% IDN_SV
@misc{datasetindonesiasinabung2018,
  author = {Carr, B.},
  title = {{Sinabung Volcano} (Indonesia), {June 20, 2018}},
  year = {2021},
  publisher = {OpenTopography},
  doi = {10.5069/G8988568}
}

% KAZ_AC
@misc{datasetkazakhstanalmaty2017,
  author = {Amey, R. and Watson, C. S. and Elliott, J. and Walker, R.},
  title = {{Almaty City, Kazakhstan, 2017, Derived from {Pleiades} Tristereo Imagery}},
  year = {2021},
  publisher = {OpenTopography},
  doi = {10.5069/G9H41PMP}
}

% KSA_WA
@misc{dataset_saudiarabia_wadi_al_akhdar_2016,
  author = {Matthieu, R. and Moulin, A. and J{'o}nsson, S.},
  title = {{Digital Surface Model of {Wadi-al-Akhdar} Graben, Saudi Arabia, 2016}},
  year = {2024},
  publisher = {OpenTopography},
  doi = {10.5069/G9V40SDZ}
}

% NAM_HF
@misc{datasetnamibiahebron_2017,
  author = {Salomon, G. and Smit, J. and Muir, R. and Stevens, V. and Sloan, R. A.},
  title = {{Hebron Fault, Namibia 2017 {WorldView-3} Stereophotogrammetric {DEM}}},
  year = {2021},
  publisher = {OpenTopography},
  doi = {10.5069/G9W957BC}
}

% NZL_KP
@misc{datasetnewzealand,
  author = {{Toit{\=u} Te Whenua Land Information New Zealand ({LINZ})}},
  title = {New Zealand {LiDAR} 1m {DEM}},
  year = {2025},
  url = {https://data.linz.govt.nz/layer/121859-new-zealand-lidar-1m-dem/services/csw/}
}

% PHL_TA
@misc{datasetphilippines,
  author = {{Disaster Risk and Exposure Assessment for Mitigation (DREAM) Program}},
  title = {{LiPAD --- {LiDAR} Portal for Archiving and Distribution}},
  year = {2016},
  url = {https://lipad.dream.upd.edu.ph/}
}

% USA_GC
@misc{datasetusa,
  author = {{U.S. Geological Survey}},
  title = {{3D Elevation Program (3DEP) Digital Elevation Models}},
  year = {2026},
  url = {https://apps.nationalmap.gov/downloader/}
}

9. Version History

Version Date Changes Author
1.0 2026-03-30 Initial release; GER_BN 20,000+ handcrafted annotations Correa et al.
1.1 2026-05-11 Expanded to 13 cities; reorganized into labelled/unlabelled; added per-region metadata; synchronized with FAIR + OGC 23-008r3 Correa et al.

10. Acknowledgments & Funding

  • Data providers: European Commission / ESA (Copernicus), Prefeitura de São Paulo (GeoSampa), OpenTopography, CNIG (Spain), Maanmittauslaitos (Finland), Geobasis NRW (Germany), LINZ (New Zealand), UP Diliman TCAGP / DREAM (Philippines), USGS (United States)
  • Imagery providers: CNES / Airbus DS (Pleiades), Maxar (WorldView-3), SPOT Image (SPOT 6)
  • Institutional support: Universidade Federal de Viçosa (UFV)

11. Contact & Support


Last Updated: 2026-07-09