Sentinel2 RGB chips over BENELUX with ESA World Cover for Learning with Label Proportions

Region of Interest (ROI) is comprised of the Belgium, the Netherlands and Luxembourg

We use the communes administrative division which is standardized across Europe by EUROSTAT at:
https://ec.europa.eu/eurostat/web/gisco/geodata/reference-data/administrative-units-statistical-units
This is roughly equivalent to the notion municipalities in most countries.

From the link above, communes definition are taken from COMM_RG_01M_2016_4326.shp and country borders
are taken from NUTS_RG_01M_2021_3035.shp.

images: Sentinel2 RGB from 2020-01-01 to 2020-31-12
        filtered out pixels with clouds during the observation period according to QA60 band following the example
        given in GEE dataset info page, and took the median of the resulting pixels

        see https://developers.google.com/earth-engine/datasets/catalog/COPERNICUS_S2_SR_HARMONIZED

        see also https://github.com/rramosp/geetiles/blob/main/geetiles/defs/sentinel2rgbmedian2020.py

labels: ESA WorldCover 10m V100
        labels mapped to the interval [1,11] according to the following map
        { 0:0, 10: 1, 20:2, 30:3, 40:4, 50:5, 60:6, 70:7, 80:8, 90:9, 95:10, 100:11 }
        pixel value zero is reserved for invalid data.
        see https://developers.google.com/earth-engine/datasets/catalog/ESA_WorldCover_v100
        
        see also https://github.com/rramosp/geetiles/blob/main/geetiles/defs/esaworldcover.py

_aschips.geojson    the image chips geometries along with label proportions
                    for easy visualization with QGIS, GeoPandas, etc.

_communes.geojson   the communes geometries with their label prortions
                    for easy visualization with QGIS, GeoPandas, etc.

splits.csv          contains two splits of image chips in train, test, val
                    - with geographical bands at 45° angles in nw-se direction
                    - the same as above reorganized to that all chips within the same
                      commune fall within the same split.

data/               a pickle file for each image chip containing a dict with
                    - the 100x100 RGB sentinel 2 chip image
                    - the 100x100 chip level lavels
                    - the label proportions of the chip
                    - the aggregated label proportions of the commune the chip belongs to