Small tool to download Openstreetmap tiles within a certain region and zoom range.

It's not yet rock stable, but maybe you want to improve it???  :-)

1 files changed, 117 insertions, 0 deletions

diff --git a/tools/OSMDownloader/osmget.py b/tools/OSMDownloader/osmget.py
new file mode 100755
index 0000000..1a745d4
--- /dev/null
+++ b/tools/OSMDownloader/osmget.py
@@ -0,0 +1,117 @@
+#!/usr/bin/python
+#  This program is free software; you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation; version 2 of the License.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  (c) 2009 Sven Rebhan <odinshorse@googlemail.com>
+#
+
+import os
+import sys
+import math
+import time
+import string
+import urllib
+
+# Convert degree into radians
+def deg2Rad(deg):
+	return (deg * math.pi / 180.0)
+
+# That's easy as the longtitude is devided into 2^zoom stripes
+def getTileX(lat, lon, zoom):
+	return int((lon + 180.0)/360.0 * 2**zoom)
+
+# Here we need to project the latitute onto the map to get the correct y
+def getTileY(lat, lon, zoom):
+	radlat = deg2Rad(lat)
+	return int((1.0 - math.log(math.tan(radlat) + 1.0 / math.cos(radlat)) / math.pi) / 2.0 * 2**zoom)
+
+def getTileUrlSuffix(x, y, zoom):
+	return "%d/%d/%d.png" % (zoom, x, y)
+
+def downloadTile(basepath, baseurl, tilesuffix):
+	# Download the tile if it doesn't exist already
+	if not os.path.exists(os.path.join(basepath,tilesuffix)):
+		tilefile = urllib.urlopen(baseurl+"/"+tilesuffix)
+		destfile = open(os.path.join(basepath,tilesuffix), 'w')
+		destfile.write(tilefile.read())
+		tilefile.close()
+		destfile.close()
+	
+
+###############################################################################
+# MAIN
+###############################################################################
+if __name__ == '__main__':
+	if(len(sys.argv) < 5):
+		print "Usage: osmget <startpos lat,lon> <stoppos lat,lon> <zoom start[:stop]> <destpath> [sleep in ms]"
+		exit(1)
+
+	# Parse the command line options
+	startpos  = string.split(sys.argv[1], ',')
+	stoppos   = string.split(sys.argv[2], ',')
+	zoomrange = string.split(sys.argv[3], ':')
+	destpath  = sys.argv[4]
+	sleeptime = 0.0
+	if len(sys.argv) > 5:
+		sleeptime = float(sys.argv[5]) / 1000.0
+	
+	print "Downloading tiles to %s (sleeping %5.3fms in between)"%(destpath, sleeptime)
+	
+	# Split the given value ranges into start and stop value
+	startzoom = int(zoomrange[0])
+	if len(zoomrange) > 1:
+		stopzoom = int(zoomrange[1])
+	else:
+		stopzoom = startzoom
+	
+	startpos_lat = float(startpos[0])
+	startpos_lon = float(startpos[1])
+	stoppos_lat  = float(stoppos[0])
+	stoppos_lon  = float(stoppos[1])
+
+	# Count the number of tiles
+	startx = getTileX(startpos_lat, startpos_lon, startzoom)
+	starty = getTileY(startpos_lat, startpos_lon, startzoom)
+	stopx  = getTileX(stoppos_lat, stoppos_lon, startzoom)
+	stopy  = getTileY(stoppos_lat, stoppos_lon, startzoom)
+	total  = 0
+	for zoom in range(0, stopzoom-startzoom+1):
+		total += 4**zoom
+	
+	total *= (stopx - startx + 1)
+	total *= (stopy - starty + 1)
+
+	# Loop over the tiles. The slowest loop should be the on the zoom
+	# level, the middle is on the x, the fastest on y.
+	count = 0
+	for zoom in range(startzoom, stopzoom+1):
+		# Calculate the bounding box of the given coords
+		startx = getTileX(startpos_lat, startpos_lon, zoom)
+		starty = getTileY(startpos_lat, startpos_lon, zoom)
+		stopx  = getTileX(stoppos_lat, stoppos_lon, zoom)
+		stopy  = getTileY(stoppos_lat, stoppos_lon, zoom)
+
+		for x in range(startx, stopx+1):
+			# Create the destination dir if it doesn't exist
+			basepath = os.path.join(destpath, str(zoom), str(x))
+			if not os.path.exists(basepath):
+				os.makedirs(basepath)
+			
+			for y in range(starty, stopy+1):
+				percent = float(count) / float(total) * 100.0
+				count = count + 1
+				print "Downloading tile %5d / %d zoom level %d (%3.1f%%)\r" %(count, total, zoom, percent),
+				sys.stdout.flush()
+				urlsuffix = getTileUrlSuffix(x, y, zoom)
+				downloadTile(destpath,
+					     "http://tile.openstreetmap.org",
+					     urlsuffix)
+				if sleeptime > 0.0:
+					time.sleep(sleeptime)
+