Python爬取谷歌地圖切片、天地圖切片
阿新 • • 發佈:2018-12-16
使用python下載地圖切片非常方便,只需要知道切片的url規則,就可以將所有地圖切片爬取下來。本文使用的python版本為3.6.
谷歌地圖衛星影像切片url如下:
http://www.google.cn/maps/[email protected]&gl=cn&x=107&y=49&z=7
我們只需要根據經緯度計算出行列號,帶入url中的xy即可,z代表zoom值。程式碼如下:
from urllib import request import re import urllib.request import os import random import math agents = [ 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.101 Safari/537.36', 'Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/532.5 (KHTML, like Gecko) Chrome/4.0.249.0 Safari/532.5', 'Mozilla/5.0 (Windows; U; Windows NT 5.2; en-US) AppleWebKit/532.9 (KHTML, like Gecko) Chrome/5.0.310.0 Safari/532.9', 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US) AppleWebKit/534.7 (KHTML, like Gecko) Chrome/7.0.514.0 Safari/534.7', 'Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US) AppleWebKit/534.14 (KHTML, like Gecko) Chrome/9.0.601.0 Safari/534.14', 'Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/534.14 (KHTML, like Gecko) Chrome/10.0.601.0 Safari/534.14', 'Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/534.20 (KHTML, like Gecko) Chrome/11.0.672.2 Safari/534.20", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.27 (KHTML, like Gecko) Chrome/12.0.712.0 Safari/534.27', 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/13.0.782.24 Safari/535.1'] # 經緯度反算切片行列號 3857座標系 def deg2num(lat_deg, lon_deg, zoom): lat_rad = math.radians(lat_deg) n = 2.0 ** zoom xtile = int((lon_deg + 180.0) / 360.0 * n) ytile = int((1.0 - math.log(math.tan(lat_rad) + (1 / math.cos(lat_rad))) / math.pi) / 2.0 * n) return (xtile, ytile) # 下載圖片 def getimg(Tpath, Spath, x, y): try: f = open(Spath, 'wb') req = urllib.request.Request(Tpath) req.add_header('User-Agent', random.choice(agents)) # 換用隨機的請求頭 pic = urllib.request.urlopen(req, timeout=60) f.write(pic.read()) f.close() print(str(x) + '_' + str(y) + '下載成功') except Exception: print(str(x) + '_' + str(y) + '下載失敗,重試') getimg(Tpath, Spath, x, y) path = r"E:\天地圖切片" if not os.path.exists(path): os.mkdir(path) zoom = 15 # 下載切片的zoom lefttop = deg2num(36.022968, 120.064056, zoom) # 下載切片的左上角角點 rightbottom = deg2num(35.894891, 120.344615, zoom) print(str(lefttop[0])) print(str(rightbottom[0])) print(str(lefttop[1])) print(str(rightbottom[1])) print("共" + str(lefttop[0] - rightbottom[0])) print("共" + str(lefttop[1] - rightbottom[1])) for x in range(lefttop[0], rightbottom[0]): for y in range(lefttop[1], rightbottom[1]): tilepath = "http://t3.tianditu.gov.cn/DataServer?T=cva_w&x=" + str(x) + "&y=" + str(y) + "&l=" + str(zoom) # 天地圖的url 可以換成谷歌地圖的 getimg(tilepath, os.path.join(path, str(x) + "_" + str(y) + ".png"), x, y) print('完成')