Convert 3D KML to GeoTIFF image

kml2tiff.sh

#!/bin/bash
#
# Convert a 3 dimension KML file into a PNG image
#
# Author : Jérôme Gasperi (https://github.com/jjrom)
# Date   : 2018-11-07
#
FILENAME=__NULL__
COLORTABLE=__NULL__
SIZE=1000x1000

function showUsage {
    echo ""
    echo "   Convert a 3 dimension KML file into a PNG image "
    echo ""
    echo "   Usage $0 [-f] KML file"
    echo ""
    echo "      -S | --size widthxheight output png size (default 1000x1000 pixels)"
    echo "      -c | --colortable use a colortable (csv file with z R G B)"
    echo "      -h | --help show this help"
    echo ""
    echo "      !!! This script requires gdal to be installed !!!"
    echo ""
}

# Parsing arguments
while [[ $# > 0 ]]
do
	key="$1"
	case $key in
        -f|--file)
            FILENAME="$2"
            shift # past argument
            ;;
        -S|--size)
            SIZE="$2"
            shift # past argument
            ;;
	-c|--colortable)
            COLORTABLE="$2"
            shift # past argument
            ;;
        -h|--help)
            showUsage
            exit 0
            shift # past argument
            ;;
            *)
        shift # past argument
        # unknown option
        ;;
	esac
done

if [ ! -f ${FILENAME} ]; then
    echo "[ERROR] Missing or invalid input KML file!"
    showUsage
    exit 0
fi

FILENAME_NOEXT=${FILENAME%.*}
WIDTH=`echo ${SIZE} | awk -Fx '{print $1}'`
HEIGHT=`echo ${SIZE} | awk -Fx '{print $2}'`

# Convert (X,Y,Z) KML to ESRI shapefile
ogr2ogr -f "ESRI Shapefile" ${FILENAME_NOEXT}.shp ${FILENAME_NOEXT}.kml

# Convert (X,Y,Z) shapefile to 8 bits TIFF image with color proportional to Z value
gdal_rasterize -3d -ts ${WIDTH} ${HEIGHT} ${FILENAME_NOEXT}.shp ${FILENAME_NOEXT}_unscaled.tif

# Rescale TIFF image values to [0,255]
if [ -f ${COLORTABLE} ]; then
    echo "[INFO] Using color table ${COLORTABLE}"
    gdaldem color-relief -nearest_color_entry ${FILENAME_NOEXT}_unscaled.tif ${COLORTABLE} ${FILENAME_NOEXT}.tif
else
    gdal_translate -scale -ot Byte ${FILENAME_NOEXT}_unscaled.tif ${FILENAME_NOEXT}.tif
fi

# Clean intermediate files
rm ${FILENAME_NOEXT}.shp ${FILENAME_NOEXT}.shx ${FILENAME_NOEXT}.dbf ${FILENAME_NOEXT}.prj ${FILENAME_NOEXT}_unscaled.tif

Use with color table

./kml2tiff.sh -f To6O120minA.kml -c colors.csv

Examples of color tables

colors.csv

0 0 0 0
0.01 0 153 255
0.99 0 153 255
1 0 102 255
2.99 0 102 255
3 0 51 255
9.99 0 51 255
10 0 0 255

colors2.csv

0 black
0.01 red
0.99 orange
1 yellow
2.99 green
3 cyan
9.99 blue
10 white