srtm_shading example

(Source code)

"""
This example illustrates the automatic download of
STRM data, gap filling (using gdal) and adding shading
to create a so-called "Shaded Relief SRTM"

Contributed by: Thomas Lecocq (http://geophysique.be)
"""

import cartopy.crs as ccrs
from cartopy.io import srtm
import matplotlib.pyplot as plt


def main():
    ax = plt.axes(projection=ccrs.PlateCarree())

    # Get the 1x1 degree SRTM tile for 12E, 47N
    elev, crs, extent = srtm.srtm_composite(12, 47, 1, 1)

    # Fill the gaps present in the elevation data
    elev_filled = srtm.fill_gaps(elev, 15)

    # Add shading simulating the Sun at 10am (South-East)
    # and with a low angle (15 degrees above horizon)
    shaded = srtm.add_shading(elev_filled, 135.0, 15.0)

    # The plot the result :
    plt.imshow(shaded, extent=extent, transform=crs,
               cmap='Greys', origin='lower')

    plt.title("SRTM Shaded Relief Map")

    gl = ax.gridlines(draw_labels=True)
    gl.xlabels_top = False
    gl.ylabels_left = False

    plt.show()


if __name__ == '__main__':
    main()