Rapid radiometric calibration of multiple camera array using in-situ data for UAV multispectral photogrammetry

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F19%3A10399035" target="_blank" >RIV/00216208:11310/19:10399035 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.5194/isprs-archives-XLII-2-W17-209-2019" target="_blank" >https://doi.org/10.5194/isprs-archives-XLII-2-W17-209-2019</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.5194/isprs-archives-XLII-2-W17-209-2019" target="_blank" >10.5194/isprs-archives-XLII-2-W17-209-2019</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Rapid radiometric calibration of multiple camera array using in-situ data for UAV multispectral photogrammetry

Popis výsledku v původním jazyce

This study compares two possible radiometric calibration approaches of Tetracam μMCA Snap multispectral camera using the Dark offset subtraction and Look-Up Table (LUT) methods. A laboratory-based calibration using correction images taken under the controlled conditions was compared with a rapid in-situ based calibration featuring correction images taken during the field campaign. The hypothesis was that the accuracy of in-situ calibration could be comparable with the laboratory calibration, and thus could replace it and simplify the radiometric calibration process. The accuracy of calibration approaches was assessed by comparison of three validation targets reflectance values extracted from corrected UAV images based on laboratory and in-situ calibration with a reference spectroscopy measurement. The results of the field experiment showed that both calibration approaches led to significant accuracy improvement compared to raw data. The vignetting correction using resulted in a significant reduction of the Coefficient of variation by half in all bands and overall equalizing the DNs on the selected diagonal profile. The NRMSEs after processing all corrections ranged from 0.24 to 3.40%. Although the statistical testing revealed slightly better agreement of laboratory calibrated reflectance with reference data, the accuracy of in-situ calibration is sufficient, because the accuracy improvement quantified by the NRMSE is 2 - 10 times better using both calibration approaches compared to raw data than the NRMSE differences between them. These findings make the proposed in-situ approach usable for various environmental studies featuring UAV multispectral photogrammetry.

Název v anglickém jazyce

Rapid radiometric calibration of multiple camera array using in-situ data for UAV multispectral photogrammetry

Popis výsledku anglicky

This study compares two possible radiometric calibration approaches of Tetracam μMCA Snap multispectral camera using the Dark offset subtraction and Look-Up Table (LUT) methods. A laboratory-based calibration using correction images taken under the controlled conditions was compared with a rapid in-situ based calibration featuring correction images taken during the field campaign. The hypothesis was that the accuracy of in-situ calibration could be comparable with the laboratory calibration, and thus could replace it and simplify the radiometric calibration process. The accuracy of calibration approaches was assessed by comparison of three validation targets reflectance values extracted from corrected UAV images based on laboratory and in-situ calibration with a reference spectroscopy measurement. The results of the field experiment showed that both calibration approaches led to significant accuracy improvement compared to raw data. The vignetting correction using resulted in a significant reduction of the Coefficient of variation by half in all bands and overall equalizing the DNs on the selected diagonal profile. The NRMSEs after processing all corrections ranged from 0.24 to 3.40%. Although the statistical testing revealed slightly better agreement of laboratory calibrated reflectance with reference data, the accuracy of in-situ calibration is sufficient, because the accuracy improvement quantified by the NRMSE is 2 - 10 times better using both calibration approaches compared to raw data than the NRMSE differences between them. These findings make the proposed in-situ approach usable for various environmental studies featuring UAV multispectral photogrammetry.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

10508 - Physical geography

Projekt

<a href="/cs/project/LTC19024" target="_blank" >LTC19024: UAS monitoring odezvy říčních systémů na změny klimatu v horském prostředí</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

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

Název statě ve sborníku

The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences

ISBN

—

ISSN

2194-9034

e-ISSN

—

Počet stran výsledku

7

Strana od-do

209-215

Název nakladatele

Copernicus GmbH

Místo vydání

Göttingen

Místo konání akce

Strasbourg

Datum konání akce

2. 12. 2019

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

—