Convert a raster to polygon, remove raster background from vector (white for image, FALSE for mask), aggregate single polygons and set vector values as a single id.
Examples
# Load station
stn <- get_metadata_frost(stationid = 18700)
# Construct box with 200 m radius to extract WMS tile
box <- make_bbox(stn, dx = 200)
# Load a tile
building <- get_tile_wms(box, layer = "bygning", px = 400)
# Convert raster tile to vector landcover
v_building <- raster_to_vector(building, id = "building", mask_thr = 255)