#!/bin/bash

GDAL_TILE_PROCESSES=16
GDAL_TILE_ZOOMS=8-14
GDAL_SAMPLING_WARP=cubic
GDAL_SAMPLING_TILE=antialias

# Create virtual dataset with coordinates
gdal_translate -of VRT -a_srs EPSG:4326 -outsize 300% 300% -gcp 0.0 0.0 26.42285996 56.9369201 -gcp 21600.0 0.0 26.43734769 57.03334843 -gcp 21600.0 22038.0 26.60996981 57.02231921 -gcp 0.0 22038.0 26.5969215 56.93247659 GX825/GX_825_SK_frame_46.jpg GX_825_SK_frame_46.vrt

# Add cutline to VRT
gdalwarp -r $GDAL_SAMPLING_WARP -tps -dstalpha -cutline_srs EPSG:4326 \
  -cutline "POLYGON(($(echo -e "1080.0 2544.0\n936.0 19584.0\n21072.0 19584.0\n21288.0 2256.0" | \
  gdaltransform -tps -output_xy GX_825_SK_frame_46.vrt | \
  awk 'NR==1{first=$0} {printf "%s %s,", $1,$2} END{print " " first}')))" \
  GX_825_SK_frame_46.vrt GX_825_SK_frame_46.cut.vrt

# Generate tiles
gdal2tiles.py -r $GDAL_SAMPLING_TILE --xyz -z $GDAL_TILE_ZOOMS -x --processes=$GDAL_TILE_PROCESSES GX_825_SK_frame_46.cut.vrt GX_825_SK_frame_46.xyz