#!/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 26.48574147 56.93588806 -gcp 21600.0 0.0 26.50132179 57.03277987 -gcp 21600.0 22038.0 26.67394373 57.02062103 -gcp 0.0 22038.0 26.66025297 56.93165265 GX825/GX_825_SK_frame_45.jpg GX_825_SK_frame_45.vrt

# Add cutline to VRT
gdalwarp -r $GDAL_SAMPLING_WARP -tps -dstalpha -cutline_srs EPSG:4326 \
  -cutline "POLYGON(($(echo -e "960.0 2520.0\n936.0 19584.0\n21192.0 19848.0\n21264.0 2280.0" | \
  gdaltransform -tps -output_xy GX_825_SK_frame_45.vrt | \
  awk 'NR==1{first=$0} {printf "%s %s,", $1,$2} END{print " " first}')))" \
  GX_825_SK_frame_45.vrt GX_825_SK_frame_45.cut.vrt

# Generate tiles
gdal2tiles.py -r $GDAL_SAMPLING_TILE --xyz -z $GDAL_TILE_ZOOMS -x --processes=$GDAL_TILE_PROCESSES GX_825_SK_frame_45.cut.vrt GX_825_SK_frame_45.xyz