Source code for pyrocko.dataset.topo.srtmgl3

# http://pyrocko.org - GPLv3
#
# The Pyrocko Developers, 21st Century
# ---|P------/S----------~Lg----------
from __future__ import absolute_import

import zipfile
import os.path as op
import os
import re
# try:
#     from urllib2 import urlopen
# except ImportError:
#     from urllib.request import urlopen

import numpy as num

from pyrocko import util, config
from . import tile, dataset

citation = '''
Farr, T. G., and M. Kobrick, 2000, Shuttle Radar Topography Mission produces a
wealth of data. Eos Trans. AGU, 81:583-585.

Farr, T. G. et al., 2007, The Shuttle Radar Topography Mission, Rev. Geophys.,
45, RG2004, doi:10.1029/2005RG000183. (Also available online at
http://www2.jpl.nasa.gov/srtm/SRTM_paper.pdf)

Kobrick, M., 2006, On the toes of giants-How SRTM was born, Photogramm. Eng.
Remote Sens., 72:206-210.

Rosen, P. A. et al., 2000, Synthetic aperture radar interferometry, Proc. IEEE,
88:333-382.
'''


[docs]class AuthenticationRequired(Exception): pass
[docs]class SRTMGL3(dataset.TiledGlobalDataset): def __init__( self, name='SRTMGL3', data_dir=op.join(op.dirname(__file__), 'data', 'SRTMGL3'), raw_data_url='https://mirror.pyrocko.org/e4ftl01.cr.usgs.gov/' 'MEASURES/SRTMGL3.003/2000.02.11'): dataset.TiledGlobalDataset.__init__( self, name, 432001, 216001, 1201, 1201, num.dtype('>i2'), data_dir=data_dir, citation=citation, region=(-180., 180., -60., 60.)) self.raw_data_url = raw_data_url self._available_tilenames = None self.config = config.config()
[docs] def tilename(self, itx, ity): itx -= 180 ity -= 90 if ity >= 0: s = 'N%02i' % ity else: s = 'S%02i' % -ity if itx >= 0: s += 'E%03i' % itx else: s += 'W%03i' % -itx return s
[docs] def available_tilenames(self): if self._available_tilenames is None: fpath = op.join(self.data_dir, 'available.list') if not op.exists(fpath) or os.stat(fpath).st_size == 0: util.ensuredirs(fpath) # remote structure changed, we would have to clawl through # many pages. Now keeping tile index here: self.download_file( 'https://mirror.pyrocko.org/e4ftl01.cr.usgs.gov/' 'MEASURES/SRTMGL3.003/2000.02.11/available.list', fpath) # url = self.raw_data_url + '/' # f = urlopen(url) # data = f.read().decode() # available = re.findall( # r'([NS]\d\d[EW]\d\d\d)\.SRTMGL3\.hgt', data) # # f.close() # # with open(fpath, 'w') as f: # f.writelines('%s\n' % s for s in available) with open(fpath, 'r') as f: available = [ s.strip() for s in f.readlines() if re.match(r'^[NS]\d\d[EW]\d\d\d$', s.strip())] self._available_tilenames = set(available) return self._available_tilenames
[docs] def tilefilename(self, tilename): return tilename + '.SRTMGL3.hgt.zip'
[docs] def tilepath(self, tilename): fn = self.tilefilename(tilename) return op.join(self.data_dir, fn)
[docs] def download_tile(self, tilename): fpath = self.tilepath(tilename) fn = self.tilefilename(tilename) url = self.raw_data_url + '/' + fn try: # we have to follow the oauth redirect here... self.download_file(url, fpath) except Exception as e: raise e
[docs] def download(self): for tn in self.available_tilenames(): fpath = self.tilepath(tn) if not op.exists(fpath): self.download_tile(tn)
[docs] def get_tile(self, itx, ity): tn = self.tilename(itx, ity) if tn not in self.available_tilenames(): return None else: fpath = self.tilepath(tn) if not op.exists(fpath): self.download_tile(tn) zipf = zipfile.ZipFile(fpath, 'r') rawdata = zipf.read(tn + '.hgt') zipf.close() data = num.fromstring(rawdata, dtype=self.dtype) assert data.size == self.ntx * self.nty data = data.reshape(self.nty, self.ntx)[::-1, ::] return tile.Tile( self.xmin + itx*self.stx, self.ymin + ity*self.sty, self.dx, self.dx, data)
if __name__ == '__main__': import sys util.setup_logging('pyrocko.topo.srtmgl3', 'info') if len(sys.argv) != 2: sys.exit('usage: python -m pyrocko.topo.srtmgl3 download') if sys.argv[1] == 'download': srtmgl3 = SRTMGL3() srtmgl3.download()