kmldecimate.py

import argparse
import datetime
import sys

parser = argparse.ArgumentParser(description='decimate (and retime) a folder or track from a kml file')
#parser.add_argument('-i', '--ifile', metavar='F', type=str, action='store', default = "20170527 Corral couloir.kml",
parser.add_argument('-i', '--ifile', metavar='F', type=str, action='store', default = None,
                    help='input file. Leave blank to use stdin')
parser.add_argument('-o', '--ofile', metavar='F', type=str, action='store', default = None,
                    help='output file. Leave blank for stdout, use "-" to append "_dec" to input filename')
parser.add_argument('-d', '--interval', metavar='F', type=int, action='store', default = 50,
                    help='Decimation interval. default = %(default)s')
#parser.add_argument('--folder', metavar='F', type=str, action='store', default = "Points",
parser.add_argument('--folder', metavar='F', type=str, action='store', default = None,
                    help='Folder name')
#parser.add_argument('--tracks', metavar='F', type=str, action='store', default = Points,
parser.add_argument('--tracks', metavar='F', type=str, action='store', default = None,
                    help='Track name')
parser.add_argument('-n', dest='retime', action='store_false', default = True,
                    help='No retime. Default is to retime the decimated track')
parser.add_argument('-t', '--timeincr', metavar='F', type=str, action='store', default = "min",
                    help='time increment [sec|min|hour]')
parser.add_argument('--append_str', metavar='F', type=str, action='store', default = '_dec',
                    help='String to append to names in the kml output')
parser.add_argument('-v', dest='verbose', action='store_true', default = False,
                    help='print some debug info')

opts = parser.parse_args()
if opts.verbose:
    print opts

ofile = None
fout = None
if opts.ifile:
    f = open(opts.ifile)
else:
    f = sys.stdin

if opts.ofile:
    if opts.ofile[0] == "-":
        if opts.ifile:
            ofile = opts.ifile.split('.')[0] +'_dec.' +opts.ifile.split('.')[1]
        else:
            ofile = "kmldecimate_dec.kml"
        print "ofile: " +str(ofile)
    else:
        ofile = opts.ofile
    fout = open(ofile, 'w')
else:
    fout = sys.stdout


#--------------------------------------------------------------
def folder2track(s, track_name, dlm="   ", eol="\n"):
#--------------------------------------------------------------
    if opts.verbose:
        print "folder2track()"
    track = dlm +"<Placemark>" +eol
    track += dlm +dlm +"<name>" +track_name +"</name>" +eol
    track += dlm +dlm +"<visibility>0</visibility>\n"
    track += dlm +dlm +"<open>1</open>" +eol

    track += """		<StyleMap>
			<Pair>
				<key>normal</key>
				<Style>
					<IconStyle>
						<scale>1</scale>
						<Icon>
							<href>http://maps.google.com/mapfiles/kml/shapes/track.png</href>
						</Icon>
					</IconStyle>
					<LineStyle>
						<color>ff40c4ff</color>
						<width>3</width>
					</LineStyle>
				</Style>
			</Pair>
			<Pair>
				<key>highlight</key>
				<Style>
					<IconStyle>
						<scale>1.33</scale>
						<Icon>
							<href>http://maps.google.com/mapfiles/kml/shapes/track.png</href>
						</Icon>
					</IconStyle>
					<LineStyle>
						<color>ff40c4ff</color>
						<width>4</width>
					</LineStyle>
				</Style>
			</Pair>
		</StyleMap>"""
    track += eol


    track += dlm +dlm +"<gx:Track>" +eol
    coordinates = ""
    times = ""
    for line in s.split("\n"):
        #print "folder2track: line = " +line
        if "<TimeStamp><when>" in line:
            t = line.split('>')[2].split('<')[0]
            #print "folder2track: t = " +t
            times += dlm +dlm +dlm +"<when>"
            times += t
            times += "</when>" +eol
        if "<coordinates>" in line:
            coord = line.split('>')[1].split('<')[0]
            #print "folder2track: coord = " +coord
            coordinates += dlm +dlm +dlm +"<gx:coord>"
            coordinates += coord
            coordinates += "</gx:coord>" +eol

    track += times
    track += coordinates
    track += dlm +dlm +dlm +"<ExtendedData>" +eol
    track += dlm +dlm +dlm +dlm +'<Data name="name">' +eol
    track += dlm +dlm +dlm +dlm +dlm +"<value>" +track_name +"</value>" +eol
    track += dlm +dlm +dlm +dlm +"</Data>" +eol
    track += dlm +dlm +dlm +"</ExtendedData>" +eol
    track += dlm +dlm +"</gx:Track>" +eol
    track += dlm +"</Placemark>" +eol

    return track

#--------------------------------------------------------------
def retime_track(track, dlm="   ", eol="\n"):
#--------------------------------------------------------------
    start = False
    inside_track = False
    ret_track = ""
    for line in track.split("\n"):
        if "<gx:Track>" in line:
            inside_track = True
        elif "</gx:Track>" in line:
            inside_track = False
            start = False
		
        if "<when>" in line and inside_track:
            n_leading_spaces = len(line) - len(line.lstrip())
            leading_spaces = ''
            for n in range(n_leading_spaces):
                leading_spaces = leading_spaces + line[0]
            if not start:
                s = line.split('>')[1].split('<')[0]
                print "retiming with Start Time: " +str(s)
                s = s.split('T')
                d = s[0].split('-')
                year = int(d[0])
                month = int(d[1])
                day = int(d[2])

                tline = s[1].split(':')
                hour = int(tline[0])
                minute = int(tline[1])
                #second = int(tline[2].split('Z')[0])
                second = int(tline[2][0:-1])

                timezone = tline[2][-1]

                #print ",".join([year, month, day, hour, minute, second])
                start = datetime.datetime(year,month,day,hour,minute,second)
                t = start
            else:
                if opts.timeincr[0] == 's':
                    delta = datetime.timedelta(0,1)
                elif opts.timeincr[0] == 'm':
                    delta = datetime.timedelta(0,60)
                elif opts.timeincr[0] == 'h':
                    delta = datetime.timedelta(0,3600)
                t = t + delta
            #print "time: " +str(timenow)
            lineout = leading_spaces +t.strftime("<when>%Y-%m-%dT%H:%M:%S") +timezone +"</when>\n"
            ret_track += lineout
        else:
            ret_track += line +"\n"
    return ret_track

#-----------------------------------
if opts.tracks:
#-----------------------------------
    # Handle the case of tracks
    have_track_name = False
    start = False
    inside_track = False
    n = 0
    npoints = 1
    last_line = ""
    dec_track = ""
    with f:
        for line in f:
            if "<Placemark>" in last_line and "<name>" in line:
                name = line.split('>')[1].split('<')[0]
                if name == opts.tracks:
                    have_track_name = True
            if "<gx:Track>" in line and have_track_name:
                inside_track = True
            elif "</gx:Track>" in line:
                inside_track = False
                n = 0
            elif "</Placemark>" in line:
                dec_track += line
                have_track_name = False
            elif "<when>" in last_line and "<gx:coord>" in line:
                n = 0
          
            if ("<when>" in line or "<gx:coord>" in line) and inside_track:
                n = n + 1;
                if n == opts.interval:
                   fout.write(line) 
                   dec_track += line
                   n = 0
                   npoints += 1
            else:
                if have_track_name:
                    if "Data name" in last_line and "value" in line:
                        name = line.split('>')[1].split('<')[0]
                        dec_track += line.replace(name, name+opts.append_str)
                    elif "<Placemark>" in last_line and "<name>" in line:
                        dec_track += last_line
                        dec_track += line.replace(name, name+opts.append_str)
                    else:
                        dec_track += line
                if "</Document>" in line:
                    #if opts.verbose:
                    #    print "Document line = " +line
                    if opts.retime:
                        ret_tracks = retime_track(dec_track)
                        fout.write(ret_tracks)
                    else:
                        fout.write(dec_track)
                fout.write(line) 
            last_line = line
    print "Decimated to " +str(npoints) +" points in track"

elif opts.folder:
    # Handle the case of a folder of placemarks
    dec_tracks = ""
    folder_out_str = ""
    store_folder = False
    have_folder_name = False
    name = False
    placemark = False
    n = opts.interval
    npoints = 1
    last_line = ""
    #with open(opts.ifile) as f:
    with f:
        for line in f:
            if "</Folder>" in line:
                name = False
                if have_folder_name:
                    store_folder = True
                    dec_tracks = folder2track(folder_out_str, "dec_tracks")
                    if opts.retime:
                        ret_tracks = retime_track(dec_tracks)
                have_folder_name = False
            if "</Folder>" in last_line:
                store_folder = False

            if "<Folder>" in last_line and "<name>" in line:
                name = line.split('>')[1].split('<')[0]
                print "folder name = " +str(name)
                if name == opts.folder:
                    have_folder_name = True
                    folder_out_str += last_line
                    store_folder = True

            if have_folder_name:
                if "</Placemark>" in last_line:
                   placemark = False
                   store_folder = False
                if "<Placemark>" in line:
                    placemark = True
                    n = n + 1;
                    if n >= opts.interval:
                       store_folder = True
                       n = 0
                       npoints += 1
                    else:
                       store_folder = False
                    #print str(n) +"    " +str(placemark) +"    " +str(store_folder)

                #print "hfn " +str(n) +"    " +str(placemark) +"    " +str(store_folder)

            if store_folder:
                if "<Folder>" in last_line and "<name>" in line:
                    folder_out_str += line.replace(name, name+opts.append_str)
                    leading_space = line[:len(line)-len(line.lstrip())]
                    folder_out_str += leading_space +"<visibility>0</visibility>\n"
                elif "<Placemark>" in last_line and "<name>" in line:
                    folder_out_str += line
                    leading_space = line[:len(line)-len(line.lstrip())]
                    folder_out_str += leading_space +"<visibility>0</visibility>\n"
                else:
                    folder_out_str += line
            if "</Document>" in line:
                fout.write(folder_out_str)
                if opts.retime:
                    fout.write(ret_tracks)
                else:
                    fout.write(dec_tracks)
                #print dec_tracks
            fout.write(line) 

            last_line = line
    print "Decimated to " +str(npoints) +" points in folder"


else:
    # TODO: handle paths formatted as triplets, like the one below
    """
       <Placemark>
          <name>Path</name>
          <styleUrl>#lineStyle</styleUrl>
          <LineString>
             <tessellate>1</tessellate>
             <coordinates>
                6.960669,45.947431,3242.8 6.960675,45.947429,3242.8 ...
             </coordinates>
          </LineString>
       </Placemark>
    """

#:vim ts=4