def regular_grid(self, width, height, overlap=0.0, units='native'):
"""Create a dataframe that defines the a regular grid of samples.
The width and height are given in pixels and multiplied by the
pixel size of the raster to create samples at the native
resolution of the raster.
Note: in this context width and height are unrelated to the
DL model inputs.
Args:
width (int): sample size
height (int): sample size
units (str): units applied to sample sizes ('native' or 'pixels')
overlap (float): percentage overlap (default=0.0)
Returns:
(GeoDataframe)
"""
if not self.src:
raise RuntimeError('source not set or failed to open')
if units == 'pixels':
dims = width * self.src.res[0], height * self.src.res[1]
elif units == 'native':
dims = width, height
else:
raise ValueError('units must be "native" or "pixels"')
gdf = grid.regular_grid(*self.src.bounds, *dims, overlap=overlap)
gdf.crs = self.src.crs
return gdf
def regular_grid(self, width, height, overlap=0.0, units='native'):
"""Create a dataframe that defines the a regular grid of samples.
When units='native', width and height are given in projection
units (i.e. meters, feet, etc). The number of pixels within this
area would depend on the pixel size. If units='pixel', width
and height are multiplied by the pixel size to compute the
sample boundaries.
Note: width and height are unrelated to the DL model inputs.
Args:
width (int): sample size
height (int): sample size
units (str): units applied to sample sizes ('native' or 'pixels')
overlap (float): percentage overlap (default=0.0)
Returns:
(GeoDataframe)
"""
if not self.src:
raise RuntimeError('source not set or failed to open')
if units == 'pixels':
dims = width * self.src.res[0], height * self.src.res[1]
elif units == 'native':
dims = width, height
else:
raise ValueError('units must be "native" or "pixels"')
gdf = grid.regular_grid(*self.src.bounds, *dims, overlap=overlap)
gdf.crs = self.src.crs
return gdf
def regular_grid(self, width=0, height=0, overlap=0.0):
"""Create a dataframe that defines the a regular grid of samples.
The width and height are given in pixels and multiplied by the
pixel size of the raster to create samples at the native
resolution of the raster.
Args:
width (int): sample size in pixels
height (int): sample size in pixels
overlap (float): percentage overlap (default=0.0)
Returns:
(GeoDataframe)
"""
width = width if width else self.width
height = height if height else self.height
if width < 1 or height < 1:
raise ValueError('width and height must be specified')
if not self.src:
raise RuntimeError('source not set or failed to open')
dims = width * self.src.res[0], height * self.src.res[1]
gdf = grid.regular_grid(*self.src.bounds, *dims, overlap=overlap)
gdf.crs = self.src.crs
return gdf
def test_regular_grid_overlap():
bounds, _, _ = grid.raster_meta('data/small.tif')
size = (bounds[2]-bounds[0], bounds[3]-bounds[1])
size = [i/10 for i in size]
df = grid.regular_grid(*bounds, *size, overlap=.5)
assert len(df) == 400
assert df.total_bounds[0] >= bounds[0]
assert df.total_bounds[1] >= bounds[1]
assert df.total_bounds[2] <= bounds[2]
assert df.total_bounds[3] <= bounds[3]