Mask from a vector

This example demonstrates the creation of a mask from a vector using geoutils.Vector.create_mask().

We open a raster and vector.

import geoutils as gu

filename_rast = gu.examples.get_path("everest_landsat_b4")
filename_vect = gu.examples.get_path("everest_rgi_outlines")
rast = gu.Raster(filename_rast)
vect = gu.Vector(filename_vect)

Let’s plot the raster and vector.

rast.plot(cmap="Purples")
vect.plot(ref_crs=rast, fc="none", ec="k", lw=2)

First option: using the raster as a reference to match, we create a mask for the vector in any projection and georeferenced grid. We simply have to pass the Raster as single argument to rasterize(). See Match-reference functionality for more details.

vect_rasterized = vect.create_mask(rast)
vect_rasterized.plot(ax="new")

Note

This is equivalent to using rasterize() with in_value=1 and out_value=0 and will return a Mask.

vect_rasterized

Mask(
  data=[[ True  True  True ...  True  True  True]
        [ True  True  True ...  True  True  True]
        [ True  True  True ...  True  True  True]
        ...
        [False False False ... False  True  True]
        [False False False ... False  True  True]
        [False False False ...  True  True  True]]
  transform=| 30.00, 0.00, 478000.00|
            | 0.00,-30.00, 3108140.00|
            | 0.00, 0.00, 1.00|
  crs=EPSG:32645)

Second option: we can pass any georeferencing parameter to create_mask(). Any unpassed attribute will be deduced from the Vector itself, except from the shape to rasterize that will default to 1000 x 1000.

# vect_rasterized = vect.create_mask(xres=500)
# vect_rasterized.plot()

Important

The shape or the res are the only unknown arguments to rasterize a Vector, one or the other can be passed.