PREDICTING THE INFRARED UAV IMAGERY OVER THE COAST
The infrared (IR) imagery provides additional information to the visible (red-green-blue, RGB) about vegetation, soil, water, mineral, or temperature, and has become essential for various disciplines, such as geology, hydrology, ecology, archeology, meteorology or geography. The integration of the I...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2021-06-01
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| Series: | The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences |
| Online Access: | https://www.int-arch-photogramm-remote-sens-spatial-inf-sci.net/XLIII-B1-2021/149/2021/isprs-archives-XLIII-B1-2021-149-2021.pdf |
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| author | A. Collin A. Collin D. James A. Mury M. Letard B. Guillot |
| author_facet | A. Collin A. Collin D. James A. Mury M. Letard B. Guillot |
| author_sort | A. Collin |
| collection | DOAJ |
| description | The infrared (IR) imagery provides additional information to the visible (red-green-blue, RGB) about vegetation, soil, water, mineral, or temperature, and has become essential for various disciplines, such as geology, hydrology, ecology, archeology, meteorology or geography. The integration of the IR sensors, ranging from near-IR (NIR) to thermal-IR through mid-IR, constitutes a baseline for Earth Observation satellites but not for unmanned airborne vehicles (UAV). Given the hyperspatial and hypertemporal characteristics associated with the UAV survey, it is relevant to benefit from the IR waveband in addition to the visible imagery for mapping purposes. This paper proposes to predict the NIR reflectance from RGB digital number predictors collected with a consumer-grade UAV over a structurally and compositionally complex coastal area. An array of 15 000 data, distributed into calibration, validation and test datasets across 15 representative coastal habitats, was used to build and compare the performance of the standard least squares, decision tree, boosted tree, bootstrap forest and fully connected neural network (NN) models. The NN family surpassed the four other ones, and the best NN model (R<sup>2</sup> = 0.67) integrated two hidden layers provided, each, with five nodes of hyperbolic tangent and five nodes of Gaussian activation functions. This perceptron enabled to produce a NIR reflectance spatially-explicit model deprived of original artifacts due to the flight constraints. At the habitat scale, sedimentary and dry vegetation environments were satisfactorily predicted (R<sup>2</sup> > 0.6), contrary to the healthy vegetation (R<sup>2</sup> < 0.2). Those innovative findings will be useful for scientists and managers tasked with hyperspatial and hypertemporal mapping. |
| first_indexed | 2024-12-22T11:51:14Z |
| format | Article |
| id | doaj.art-32a625ac38ab4107a749216f8fa69966 |
| institution | Directory Open Access Journal |
| issn | 1682-1750 2194-9034 |
| language | English |
| last_indexed | 2024-12-22T11:51:14Z |
| publishDate | 2021-06-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences |
| spelling | doaj.art-32a625ac38ab4107a749216f8fa699662022-12-21T18:26:58ZengCopernicus PublicationsThe International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences1682-17502194-90342021-06-01XLIII-B1-202114915610.5194/isprs-archives-XLIII-B1-2021-149-2021PREDICTING THE INFRARED UAV IMAGERY OVER THE COASTA. Collin0A. Collin1D. James2A. Mury3M. Letard4B. Guillot5EPHE-PSL University, CNRS LETG, 35800 Dinard, FranceLabEx CORAIL, BP1013, Papetoai, French PolynesiaEPHE-PSL University, CNRS LETG, 35800 Dinard, FranceEPHE-PSL University, CNRS LETG, 35800 Dinard, FranceEPHE-PSL University, CNRS LETG, 35800 Dinard, FranceEPHE-PSL University, CNRS LETG, 35800 Dinard, FranceThe infrared (IR) imagery provides additional information to the visible (red-green-blue, RGB) about vegetation, soil, water, mineral, or temperature, and has become essential for various disciplines, such as geology, hydrology, ecology, archeology, meteorology or geography. The integration of the IR sensors, ranging from near-IR (NIR) to thermal-IR through mid-IR, constitutes a baseline for Earth Observation satellites but not for unmanned airborne vehicles (UAV). Given the hyperspatial and hypertemporal characteristics associated with the UAV survey, it is relevant to benefit from the IR waveband in addition to the visible imagery for mapping purposes. This paper proposes to predict the NIR reflectance from RGB digital number predictors collected with a consumer-grade UAV over a structurally and compositionally complex coastal area. An array of 15 000 data, distributed into calibration, validation and test datasets across 15 representative coastal habitats, was used to build and compare the performance of the standard least squares, decision tree, boosted tree, bootstrap forest and fully connected neural network (NN) models. The NN family surpassed the four other ones, and the best NN model (R<sup>2</sup> = 0.67) integrated two hidden layers provided, each, with five nodes of hyperbolic tangent and five nodes of Gaussian activation functions. This perceptron enabled to produce a NIR reflectance spatially-explicit model deprived of original artifacts due to the flight constraints. At the habitat scale, sedimentary and dry vegetation environments were satisfactorily predicted (R<sup>2</sup> > 0.6), contrary to the healthy vegetation (R<sup>2</sup> < 0.2). Those innovative findings will be useful for scientists and managers tasked with hyperspatial and hypertemporal mapping.https://www.int-arch-photogramm-remote-sens-spatial-inf-sci.net/XLIII-B1-2021/149/2021/isprs-archives-XLIII-B1-2021-149-2021.pdf |
| spellingShingle | A. Collin A. Collin D. James A. Mury M. Letard B. Guillot PREDICTING THE INFRARED UAV IMAGERY OVER THE COAST The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences |
| title | PREDICTING THE INFRARED UAV IMAGERY OVER THE COAST |
| title_full | PREDICTING THE INFRARED UAV IMAGERY OVER THE COAST |
| title_fullStr | PREDICTING THE INFRARED UAV IMAGERY OVER THE COAST |
| title_full_unstemmed | PREDICTING THE INFRARED UAV IMAGERY OVER THE COAST |
| title_short | PREDICTING THE INFRARED UAV IMAGERY OVER THE COAST |
| title_sort | predicting the infrared uav imagery over the coast |
| url | https://www.int-arch-photogramm-remote-sens-spatial-inf-sci.net/XLIII-B1-2021/149/2021/isprs-archives-XLIII-B1-2021-149-2021.pdf |
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