A comparison of constant false alarm rate object detection algorithms for iceberg identification in L- and C-band SAR imagery of the Labrador Sea
In this study, we pursue two objectives: first, we compare six different “constant false alarm rate” (CFAR) algorithms for iceberg detection in SAR images, and second, we investigate the effect of radar frequency by comparing the detection performance at C- and L-band. The SAR images were acquired o...
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Online Access: | https://hdl.handle.net/10037/32399 https://doi.org/10.5194/tc-17-5335-2023 |
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ftunivtroemsoe:oai:munin.uit.no:10037/32399 2024-02-04T10:01:55+01:00 A comparison of constant false alarm rate object detection algorithms for iceberg identification in L- and C-band SAR imagery of the Labrador Sea Færch, Laust Dierking, Wolfgang Fritz Otto Hughes, Nick Doulgeris, Anthony Paul 2023-12-15 https://hdl.handle.net/10037/32399 https://doi.org/10.5194/tc-17-5335-2023 eng eng European Geosciences Union (EGU) The Cryosphere Færch, Dierking, Hughes, Doulgeris. A comparison of constant false alarm rate object detection algorithms for iceberg identification in L- and C-band SAR imagery of the Labrador Sea. The Cryosphere. 2023;17(12):5335-5355 FRIDAID 2222429 doi:10.5194/tc-17-5335-2023 1994-0416 1994-0424 https://hdl.handle.net/10037/32399 Attribution 4.0 International (CC BY 4.0) openAccess Copyright 2023 The Author(s) https://creativecommons.org/licenses/by/4.0 Journal article Tidsskriftartikkel Peer reviewed publishedVersion 2023 ftunivtroemsoe https://doi.org/10.5194/tc-17-5335-2023 2024-01-11T00:08:09Z In this study, we pursue two objectives: first, we compare six different “constant false alarm rate” (CFAR) algorithms for iceberg detection in SAR images, and second, we investigate the effect of radar frequency by comparing the detection performance at C- and L-band. The SAR images were acquired over the Labrador Sea under melting conditions. In an overlapping optical Sentinel-2 image, 492 icebergs were identified in the area. They were used for an assessment of the algorithms' capabilities to accurately detect them in the SAR images and for the determination of the number of false alarms and missed detections. By testing the detectors at varying probability of false alarm (PFA) levels, the optimum PFA for each detector was found. Additionally, we considered the effect of iceberg sizes in relation to image resolution. The results showed that the overall highest accuracy was achieved by applying a log-normal CFAR detector to the L-band image (F score of 70.4 %), however, only for a narrow range of PFA values. Three of the tested detectors provided high F scores above 60 % over a wider range of PFA values both at L- and C-band. Low F scores were mainly caused by missed detections of small-sized (<60 m) and medium-sized (60–120 m) icebergs, with approximately 20 %–40 % of the medium icebergs and 85 %–90 % of small icebergs being missed by all detectors. The iDPolRAD detector, which is sensitive to volume scattering, is less suitable under melting conditions. Article in Journal/Newspaper Labrador Sea The Cryosphere University of Tromsø: Munin Open Research Archive The Cryosphere 17 12 5335 5355 |
institution |
Open Polar |
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University of Tromsø: Munin Open Research Archive |
op_collection_id |
ftunivtroemsoe |
language |
English |
description |
In this study, we pursue two objectives: first, we compare six different “constant false alarm rate” (CFAR) algorithms for iceberg detection in SAR images, and second, we investigate the effect of radar frequency by comparing the detection performance at C- and L-band. The SAR images were acquired over the Labrador Sea under melting conditions. In an overlapping optical Sentinel-2 image, 492 icebergs were identified in the area. They were used for an assessment of the algorithms' capabilities to accurately detect them in the SAR images and for the determination of the number of false alarms and missed detections. By testing the detectors at varying probability of false alarm (PFA) levels, the optimum PFA for each detector was found. Additionally, we considered the effect of iceberg sizes in relation to image resolution. The results showed that the overall highest accuracy was achieved by applying a log-normal CFAR detector to the L-band image (F score of 70.4 %), however, only for a narrow range of PFA values. Three of the tested detectors provided high F scores above 60 % over a wider range of PFA values both at L- and C-band. Low F scores were mainly caused by missed detections of small-sized (<60 m) and medium-sized (60–120 m) icebergs, with approximately 20 %–40 % of the medium icebergs and 85 %–90 % of small icebergs being missed by all detectors. The iDPolRAD detector, which is sensitive to volume scattering, is less suitable under melting conditions. |
format |
Article in Journal/Newspaper |
author |
Færch, Laust Dierking, Wolfgang Fritz Otto Hughes, Nick Doulgeris, Anthony Paul |
spellingShingle |
Færch, Laust Dierking, Wolfgang Fritz Otto Hughes, Nick Doulgeris, Anthony Paul A comparison of constant false alarm rate object detection algorithms for iceberg identification in L- and C-band SAR imagery of the Labrador Sea |
author_facet |
Færch, Laust Dierking, Wolfgang Fritz Otto Hughes, Nick Doulgeris, Anthony Paul |
author_sort |
Færch, Laust |
title |
A comparison of constant false alarm rate object detection algorithms for iceberg identification in L- and C-band SAR imagery of the Labrador Sea |
title_short |
A comparison of constant false alarm rate object detection algorithms for iceberg identification in L- and C-band SAR imagery of the Labrador Sea |
title_full |
A comparison of constant false alarm rate object detection algorithms for iceberg identification in L- and C-band SAR imagery of the Labrador Sea |
title_fullStr |
A comparison of constant false alarm rate object detection algorithms for iceberg identification in L- and C-band SAR imagery of the Labrador Sea |
title_full_unstemmed |
A comparison of constant false alarm rate object detection algorithms for iceberg identification in L- and C-band SAR imagery of the Labrador Sea |
title_sort |
comparison of constant false alarm rate object detection algorithms for iceberg identification in l- and c-band sar imagery of the labrador sea |
publisher |
European Geosciences Union (EGU) |
publishDate |
2023 |
url |
https://hdl.handle.net/10037/32399 https://doi.org/10.5194/tc-17-5335-2023 |
genre |
Labrador Sea The Cryosphere |
genre_facet |
Labrador Sea The Cryosphere |
op_relation |
The Cryosphere Færch, Dierking, Hughes, Doulgeris. A comparison of constant false alarm rate object detection algorithms for iceberg identification in L- and C-band SAR imagery of the Labrador Sea. The Cryosphere. 2023;17(12):5335-5355 FRIDAID 2222429 doi:10.5194/tc-17-5335-2023 1994-0416 1994-0424 https://hdl.handle.net/10037/32399 |
op_rights |
Attribution 4.0 International (CC BY 4.0) openAccess Copyright 2023 The Author(s) https://creativecommons.org/licenses/by/4.0 |
op_doi |
https://doi.org/10.5194/tc-17-5335-2023 |
container_title |
The Cryosphere |
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17 |
container_issue |
12 |
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5335 |
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5355 |
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1789968153546063872 |