#!/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 25.66979015 56.93394523 -gcp 21600.0 0.0 25.67467447 57.02889752 -gcp 21600.0 21912.0 25.84596543 57.02233561 -gcp 0.0 21912.0 25.84084657 56.93407776 GX825/GX_825_SK_frame_60.jpg GX_825_SK_frame_60.vrt

# Add cutline to VRT
gdalwarp -r $GDAL_SAMPLING_WARP -tps -dstalpha -cutline_srs EPSG:4326 \
  -cutline "POLYGON(($(echo -e "624.0 2304.0\n648.0 19416.0\n21072.0 19536.0\n21144.0 2232.0" | \
  gdaltransform -tps -output_xy GX_825_SK_frame_60.vrt | \
  awk 'NR==1{first=$0} {printf "%s %s,", $1,$2} END{print " " first}')))" \
  GX_825_SK_frame_60.vrt GX_825_SK_frame_60.cut.vrt

# Generate tiles
gdal2tiles.py -r $GDAL_SAMPLING_TILE --xyz -z $GDAL_TILE_ZOOMS -x --processes=$GDAL_TILE_PROCESSES GX_825_SK_frame_60.cut.vrt GX_825_SK_frame_60.xyz