BigEarthNet Labels#
BigEarthNet used the CORINE Land Cover database (CLC) of the year 2018 (CLC2018) to label 590’326 patches. The label information about these patches were overlayed with data from the Sentinel-1 and Sentinel-2 mission, to create the datasets BigEarthnet-S1 and BigEarthNet-S2. BigEarthNet-S2 was the first published dataset and used the most specific version of the classification level of the CLC database, Level-3 with 43 different classes in the dataset [2]. With the publication of the BigEarthNet-S1 dataset, the recommended label nomenclature has been updated to use a 19-class nomenclature specifically designed for use in the machine-learning domain. [3].
Important
The original BigEarthNet-S2 dataset used the CLC Level-3 specification, which defines 44 classes
Of these 44-classes one class,
Glaciers and perpetual snowis not presentAs a result the label-set is referred to as the 43-label nomenclature.
The 19-class label nomenclature was introduced to better reflect the application in the machine learning domain
43-class nomenclature#
The CORINE (Coordination of Information on the Environment) Land Cover nomenclature is a nomenclature used to describe physical material at the surface of the earth. The CLC nomenclature defines a standardized classification schema that can be used for annotating remote imagery.
The CLC classification schema is defined as a 3-level deep hierarchy with:
5 classes in level 1
15 classes in level 2
44 classes in level 3
The following box shows the label hierarchy in a tabular form. More in-depth information about the CLC2018 nomenclature, including example images for each level-3 label, can be reviewed on the Corine-Land-Cover-Nomenclature-Guidelines site.
| CLC_LVL1 | CLC_LVL2 | CLC_LVL3 |
|---|---|---|
| Agricultural areas | Arable land | Non-irrigated arable land |
| Permanently irrigated land | ||
| Rice fields | ||
| Heterogeneous agricultural areas | Agro-forestry areas | |
| Annual crops associated with permanent crops | ||
| Complex cultivation patterns | ||
| Land principally occupied by agriculture, with significant areas of natural vegetation | ||
| Pastures | Pastures | |
| Permanent crops | Fruit trees and berry plantations | |
| Olive groves | ||
| Vineyards | ||
| Artificial Surfaces | Artificial, non-agricultural vegetated areas | Green urban areas |
| Sport and leisure facilities | ||
| Industrial, comercial and transport units | Airports | |
| Industrial or commercial units | ||
| Port areas | ||
| Road and rail networks and associated land | ||
| Mine, dump and construction sites | Construction sites | |
| Dump sites | ||
| Mineral extraction sites | ||
| Urban fabric | Continuous urban fabric | |
| Discontinuous urban fabric | ||
| Forest and seminatural areas | Forest | Broad-leaved forest |
| Coniferous forest | ||
| Mixed forest | ||
| Open spaces with little or no vegetation | Bare rock | |
| Beaches, dunes, sands | ||
| Burnt areas | ||
| Glaciers and perpetual snow | ||
| Sparsely vegetated areas | ||
| Shrub and/or herbaceous vegetation associations | Moors and heathland | |
| Natural grassland | ||
| Sclerophyllous vegetation | ||
| Transitional woodland/shrub | ||
| Water bodies | Inland waters | Water bodies |
| Water courses | ||
| Marine waters | Coastal lagoons | |
| Estuaries | ||
| Sea and ocean | ||
| Wetlands | Coastal wetlands | Intertidal flats |
| Salines | ||
| Salt marshes | ||
| Inland wetlands | Inland marshes | |
| Peatbogs |
19-class nomenclature#
The 19-class nomenclature has combined and dropped classes from the 43-class variant for better use in machine learning. More specifically, ten classes of the original CLC nomenclature are maintained in the new nomenclature, 22 classes are grouped into 9 new classes, and 11 classes have been removed. Classes that strongly depend on land use or require additional data for their discrimination were removed.
The change was necessary because there are some CLC classes that are difficult to be identified by only exploiting (single-date) Sentinel-2 images, because:
Land use concepts associated with some classes may not be visible from space or fully recognizable with the spatial resolution of Sentinel-2 images, such as:
Dump sites, Sport, and leisure facilities
RS time series, which BigEarthNet does not include, may be required to describe and discriminate some classes , such as:
Non-irrigated arable land, or permanently irrigated land
The following table displays the exact the mapping from the old to the new class nomenclature.
Important
11 classes were dropped from the original 43-class nomenclature. As a result, there are 57 patches of the original BigEarthNet dataset that have no target labels. These patches should be dropped in experiments to remain compatible with the new nomenclature.
| Original 43-class label | Updated 19-class label |
|---|---|
| Continuous urban fabric | Urban fabric |
| Discontinuous urban fabric | Urban fabric |
| Industrial or commercial units | Industrial or commercial units |
| Road and rail networks and associated land | REMOVED |
| Port areas | REMOVED |
| Airports | REMOVED |
| Mineral extraction sites | REMOVED |
| Dump sites | REMOVED |
| Construction sites | REMOVED |
| Green urban areas | REMOVED |
| Sport and leisure facilities | REMOVED |
| Non-irrigated arable land | Arable land |
| Permanently irrigated land | Arable land |
| Rice fields | Arable land |
| Vineyards | Permanent crops |
| Fruit trees and berry plantations | Permanent crops |
| Olive groves | Permanent crops |
| Pastures | Pastures |
| Annual crops associated with permanent crops | Permanent crops |
| Complex cultivation patterns | Complex cultivation patterns |
| Land principally occupied by agriculture, with significant areas of natural vegetation | Land principally occupied by agriculture, with significant areas of natural vegetation |
| Agro-forestry areas | Agro-forestry areas |
| Broad-leaved forest | Broad-leaved forest |
| Coniferous forest | Coniferous forest |
| Mixed forest | Mixed forest |
| Natural grassland | Natural grassland and sparsely vegetated areas |
| Moors and heathland | Moors, heathland and sclerophyllous vegetation |
| Sclerophyllous vegetation | Moors, heathland and sclerophyllous vegetation |
| Transitional woodland/shrub | Transitional woodland, shrub |
| Beaches, dunes, sands | Beaches, dunes, sands |
| Bare rock | REMOVED |
| Sparsely vegetated areas | Natural grassland and sparsely vegetated areas |
| Burnt areas | REMOVED |
| Inland marshes | Inland wetlands |
| Peatbogs | Inland wetlands |
| Salt marshes | Coastal wetlands |
| Salines | Coastal wetlands |
| Intertidal flats | REMOVED |
| Water courses | Inland waters |
| Water bodies | Inland waters |
| Coastal lagoons | Marine waters |
| Estuaries | Marine waters |
| Sea and ocean | Marine waters |