#!/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 27.60824561 57.82610857 -gcp 21627.0 0.0 27.62497419 57.85715539 -gcp 21627.0 21123.0 27.6837551 57.84823699 -gcp 0.0 21123.0 27.66477585 57.81672659 GX856/GX_856_SK_frame_31.jpg GX_856_SK_frame_31.vrt

# Add cutline to VRT
gdalwarp -r $GDAL_SAMPLING_WARP -tps -dstalpha -cutline_srs EPSG:4326 \
  -cutline "POLYGON(($(echo -e "816.0 2016.641782729805\n21120.0 1920.6952646239556\n21072.0 18864.01334074486\n720.0 18983.879933296274" | \
  gdaltransform -tps -output_xy GX_856_SK_frame_31.vrt | \
  awk 'NR==1{first=$0} {printf "%s %s,", $1,$2} END{print " " first}')))" \
  GX_856_SK_frame_31.vrt GX_856_SK_frame_31.cut.vrt

# Generate tiles
gdal2tiles.py -r $GDAL_SAMPLING_TILE --xyz -z $GDAL_TILE_ZOOMS -x --processes=$GDAL_TILE_PROCESSES GX_856_SK_frame_31.cut.vrt GX_856_SK_frame_31.xyz