eskriett · February 25, 2025 17:00 · Jul 19, 2013 · Jul 19, 2013 · Jul 19, 2013
diff --git a/GoogleMapDownloader.py b/GoogleMapDownloader.py
@@ -38,7 +38,7 @@ def getXY(self):
 
             Returns:    An X,Y tile coordinate
         """
-        # Tiles have a size of 256 * 256
+
         tile_size = 256
 
         # Use a left shift to get the power of 2
@@ -54,7 +54,6 @@ def getXY(self):
         # Calulate the y coorindate
         point_y = ((tile_size / 2) + 0.5 * math.log((1+sin_y)/(1-sin_y)) * -(tile_size / (2 * math.pi))) * numTiles // tile_size
 
-        # Return the points as an integer tuple 
         return int(point_x), int(point_y)
 
     def generateImage(self, **kwargs):
@@ -94,11 +93,9 @@ def generateImage(self, **kwargs):
                 current_tile = str(x)+'-'+str(y)
                 urllib.urlretrieve(url, current_tile)
 
-                # Open the image
                 im = Image.open(current_tile)
                 map_img.paste(im, (x*256, y*256))
 
-                #Remove the temp file from disk
                 os.remove(current_tile)
 
         return map_img

diff --git a/GoogleMapDownloader.py b/GoogleMapDownloader.py
@@ -4,7 +4,7 @@
 #
 # A script which when given a longitude, latitude and zoom level downloads a
 # high resolution google map
-# Find the associated blog post at: http://blog.eskriett.com/?p=132
+# Find the associated blog post at: http://blog.eskriett.com/2013/07/19/downloading-google-maps/
 
 import urllib
 import Image

diff --git a/GoogleMapDownloader.py b/GoogleMapDownloader.py
@@ -0,0 +1,123 @@
+#!/usr/bin/python
+# GoogleMapDownloader.py 
+# Created by Hayden Eskriett [http://eskriett.com]
+#
+# A script which when given a longitude, latitude and zoom level downloads a
+# high resolution google map
+# Find the associated blog post at: http://blog.eskriett.com/?p=132
+
+import urllib
+import Image
+import os
+import math
+
+class GoogleMapDownloader:
+    """
+        A class which generates high resolution google maps images given
+        a longitude, latitude and zoom level
+    """
+
+    def __init__(self, lat, lng, zoom=12):
+        """
+            GoogleMapDownloader Constructor
+
+            Args:
+                lat:    The latitude of the location required
+                lng:    The longitude of the location required
+                zoom:   The zoom level of the location required, ranges from 0 - 23
+                        defaults to 12
+        """
+        self._lat = lat
+        self._lng = lng
+        self._zoom = zoom
+
+    def getXY(self):
+        """
+            Generates an X,Y tile coordinate based on the latitude, longitude 
+            and zoom level
+
+            Returns:    An X,Y tile coordinate
+        """
+        # Tiles have a size of 256 * 256
+        tile_size = 256
+
+        # Use a left shift to get the power of 2
+        # i.e. a zoom level of 2 will have 2^2 = 4 tiles
+        numTiles = 1 << self._zoom
+
+        # Find the x_point given the longitude
+        point_x = (tile_size/ 2 + self._lng * tile_size / 360.0) * numTiles // tile_size
+
+        # Convert the latitude to radians and take the sine
+        sin_y = math.sin(self._lat * (math.pi / 180.0))
+
+        # Calulate the y coorindate
+        point_y = ((tile_size / 2) + 0.5 * math.log((1+sin_y)/(1-sin_y)) * -(tile_size / (2 * math.pi))) * numTiles // tile_size
+
+        # Return the points as an integer tuple 
+        return int(point_x), int(point_y)
+
+    def generateImage(self, **kwargs):
+        """
+            Generates an image by stitching a number of google map tiles together.
+            
+            Args:
+                start_x:        The top-left x-tile coordinate
+                start_y:        The top-left y-tile coordinate
+                tile_width:     The number of tiles wide the image should be -
+                                defaults to 5
+                tile_height:    The number of tiles high the image should be -
+                                defaults to 5
+            Returns:
+                A high-resolution Goole Map image.
+        """
+
+        start_x = kwargs.get('start_x', None)
+        start_y = kwargs.get('start_y', None)
+        tile_width = kwargs.get('tile_width', 5)
+        tile_height = kwargs.get('tile_height', 5)
+
+        # Check that we have x and y tile coordinates
+        if start_x == None or start_y == None :
+            start_x, start_y = self.getXY()
+
+        # Determine the size of the image
+        width, height = 256 * tile_width, 256 * tile_height
+
+        #Create a new image of the size require
+        map_img = Image.new('RGB', (width,height))
+
+        for x in range(0, tile_width):
+            for y in range(0, tile_height) :
+                url = 'https://mt0.google.com/vt?x='+str(start_x+x)+'&y='+str(start_y+y)+'&z='+str(self._zoom)
+
+                current_tile = str(x)+'-'+str(y)
+                urllib.urlretrieve(url, current_tile)
+
+                # Open the image
+                im = Image.open(current_tile)
+                map_img.paste(im, (x*256, y*256))
+
+                #Remove the temp file from disk
+                os.remove(current_tile)
+
+        return map_img
+
+def main():
+    # Create a new instance of GoogleMap Downloader
+    gmd = GoogleMapDownloader(51.5171, 0.1062, 13)
+
+    print("The tile coorindates are {}".format(gmd.getXY()))
+
+    try:
+        # Get the high resolution image
+        img = gmd.generateImage()
+    except IOError:
+        print("Could not generate the image - try adjusting the zoom level and checking your coordinates")
+    else:
+        #Save the image to disk
+        img.save("high_resolution_image.png")
+        print("The map has successfully been created")
+
+
+if __name__ == '__main__':  main()