deadtrees/scripts

Preprocessing Pipeline 🪠

Stage 0 (not tracked)

Data origin

Data is sources from the The luxembourgish data platform.

• 2017: RGB Image, NIR Image
• 2018: RGB Image, NIR Image
• 2019: RGB Image, NIR Image
• 2020: RGB Image, NIR Image

Data is provided as JPEG2000 encoded 3-band images with 20cm resolution and projected in EPSG:2169 (LUREF). Data for 2020 is provided in 10cm resolution and downsampled in preprocessing to match the other years.

Initial recombination and reprojection

Prior to the DVC-tracked preprocessing steps the raw data was reorganized as follows (the final output files are tracked in this repo though):

YEAR=2020

if [[ $YEAR -eq 2017 ]]
then
  RGB=ortho2017_RVB_pays.jp2
  NIR=LUX17_CIR_v3.jp2
elif [[ $VAR -eq 2018 ]]
then
  RGB=ortho2018_RGB_pays.jp2
  NIR=ortho2018_CIR_pays.jp2
elif [[ $VAR -eq 2019 ]]
then
  RGB=ortho_2019.jp2
  NIR=ortho_2019ir.jp2
elif [[ $VAR -eq 2020 ]]
then
  RGB=Luxembourg-2020_ortho10cm_RVB_LUREF.jp2
  NIR=Luxembourg-2020_ortho10cm_PIR_LUREF.jp2
else 
  echo "Undefined Year: ${YEAR}"
  exit -1
fi


# merge bands (allow projection difference since one source has a differnt projection string but correct projection parameters)
gdalbuildvrt b1.vrt -b 1 ${RGB} 
gdalbuildvrt b2.vrt -b 2 ${RGB}
gdalbuildvrt b3.vrt -b 3 ${RGB}
gdalbuildvrt b4.vrt -b 1 ${NIR}
gdalbuildvrt -allow_projection_difference -separate allbands.vrt b1.vrt b2.vrt b3.vrt b4.vrt

gdal_translate -of GTiff -co "COMPRESS=LZW" -co "PREDICTOR=2" -co "TILED=YES" -co "BIGTIFF=YES" -co "ALPHA=NO" -colorinterp_1 "red" -colorinterp_2 "green" -colorinterp_3 "blue" allbands.vrt ortho_ms_${YEAR}.tif

# reproject and limit extent to common area
gdalwarp -co "NUM_THREADS=ALL_CPUS" -multi  -overwrite -ot Byte -ts 302346 420442 -te 263584.672 5479988.018 324060.605 5564085.859 -t_srs '+proj=utm +zone=32 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs' -r average ortho_ms_2017.tif ortho_ms_${YEAR}_EPSG3044.vrt
gdal_translate -co "NUM_THREADS=ALL_CPUS" -co "COMPRESS=LZW" -co "PREDICTOR=2" -co "TILED=YES" -co "BIGTIFF=YES" -co "ALPHA=NO" ortho_ms_${YEAR}_EPSG3044.vrt ortho_ms_${YEAR}_EPSG3044.tif