Articles | Volume 13, issue 5
https://doi.org/10.5194/esurf-13-923-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/esurf-13-923-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Sep 2025
Research article |
| 24 Sep 2025
| 24 Sep 2025
Curvature-based pebble segmentation for reconstructed surface meshes
Aljoscha Rheinwalt
CORRESPONDING AUTHOR
Institute of Geosciences, University of Potsdam, Karl-Liebknecht-Str. 24–25, 14476 Potsdam-Golm, Germany
Benjamin Purinton
Institute of Geosciences, University of Potsdam, Karl-Liebknecht-Str. 24–25, 14476 Potsdam-Golm, Germany
Bodo Bookhagen
Institute of Geosciences, University of Potsdam, Karl-Liebknecht-Str. 24–25, 14476 Potsdam-Golm, Germany
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Vito Chan, Aljoscha Rheinwalt, and Bodo Bookhagen
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This preprint is open for discussion and under review for Earth Surface Dynamics (ESurf).
Short summary
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OrthoSAM is a new method that uses Segment Anything Model (SAM) to automatically identify and outline individual pebbles in high-resolution aerial images. OrthoSAM divides large photos into smaller sections that SAM can process effectively, and it improves the way to tell SAM where to look for objects. It uses a multi-resolution approach to handle different sizes, and it can be used to determine the distribution. Tests with computer-generated images and field data show that it is very precise.
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Short summary
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OrthoSAM is a new method that uses Segment Anything Model (SAM) to automatically identify and outline individual pebbles in high-resolution aerial images. OrthoSAM divides large photos into smaller sections that SAM can process effectively, and it improves the way to tell SAM where to look for objects. It uses a multi-resolution approach to handle different sizes, and it can be used to determine the distribution. Tests with computer-generated images and field data show that it is very precise.
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This study investigates the use of optical PlanetScope data for offset tracking of the Earth's surface movement. We found that co-registration accuracy is locally degraded when outdated elevation models are used for orthorectification. To mitigate this bias, we propose to only correlate scenes acquired from common perspectives or base orthorectification on more up-to-date elevation models generated from PlanetScope data alone. This enables a more detailed analysis of landslide dynamics.
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Short summary
Our study presents a computer-based method to detect and measure pebbles in 3D models reconstructed from camera photos. We tested it in a controlled setup and achieved 98 % accuracy in detecting pebbles. Unlike traditional 2D methods, our approach provides full 3D size and orientation data. This improves sediment analysis and riverbed studies by offering more precise measurements. Our work highlights the potential of 3D modeling for studying natural surfaces.
Our study presents a computer-based method to detect and measure pebbles in 3D models...
