Cross-Polarized SfM Photogrammetry for the Spatial Reconstruction of Challenging Surfaces, the Case Study of Dobšiná Ice Cave (Slovakia)

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989100%3A27350%2F23%3A10253826" target="_blank" >RIV/61989100:27350/23:10253826 - isvavai.cz</a>

Result on the web

<a href="https://www.mdpi.com/2072-4292/15/18/4481" target="_blank" >https://www.mdpi.com/2072-4292/15/18/4481</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/rs15184481" target="_blank" >10.3390/rs15184481</a>

Result language

angličtina

Original language name

Cross-Polarized SfM Photogrammetry for the Spatial Reconstruction of Challenging Surfaces, the Case Study of Dobšiná Ice Cave (Slovakia)

Original language description

Geodetic methods are integral to mapping surface and subsurface objects and phenomena. Modern geodetic technologies such as laser scanning and digital photogrammetry have also become a standard part of the mapping and documentation of cave spaces. In some cases, these technologies cannot accurately capture the measured surface and thus provide reliable data. One such example is the ice with specific surface characteristics in caves with ice deposits. One of the world&apos;s most studied ice caves is the Dobšiná Ice Cave (Slovakia), which has undergone significant changes in the ice-filling area and volume in recent years. To monitor and analyze all these changes properly, we need to know the surface and volume of this ice mass and monitor it regularly. Where modern geodetic methods such as terrestrial laser scanning (TLS) or digital photogrammetry may fail due to the ice&apos;s physical properties, we propose using cross-polarized Structure-from-Motion (SfM) photogrammetry. As a case study, this method was used in a 28 m long ice tunnel in this cave. Two polarizing filters (on the flash as a light source and on the camera lens) were used in 90o rotation to each other to achieve the cross-polarization effect and remove surface reflections. This removed the surface reflections, giving us a compact and accurate point cloud of the entire tunnel. The dense cloud from cross-polarized (CP) photogrammetry is denser and more compact and does not contain as many outliers and noise points when compared to non-cross-polarized (non-CP) photogrammetry. The TLS point cloud covers the entire surface of the tunnel without significant holes; however, the penetration of the beam through the ice makes such a cloud unusable. Only the cloud from CP photogrammetry covers the entire surface of the tunnel densely enough without additional noise. This methodology can then be used in other parts of the cave or other geomorphological applications to suppress reflections so high-quality results for further processing and analysis can be obtained. (C) 2023 by the authors.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10508 - Physical geography

Project

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Continuities

V - Vyzkumna aktivita podporovana z jinych verejnych zdroju

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Remote Sensing

ISSN

2072-4292

e-ISSN

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Volume of the periodical

15

Issue of the periodical within the volume

18

Country of publishing house

CH - SWITZERLAND

Number of pages

18

Pages from-to

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UT code for WoS article

001078118600001

EID of the result in the Scopus database

2-s2.0-85173061591