def test_segmentize_geometry():
"""Segmentize function."""
# Polygon
polygon = box(-18, -9, 18, 9)
out = segmentize_geometry(polygon, 1)
assert out.is_valid
# wrong type
with pytest.raises(TypeError):
segmentize_geometry(polygon.centroid, 1)
def bbox(self, out_crs=None):
"""
Return data bounding box.
Parameters
----------
out_crs : ``rasterio.crs.CRS``
rasterio CRS object (default: CRS of process pyramid)
Returns
-------
bounding box : geometry
Shapely geometry object
"""
out_crs = self.pyramid.crs if out_crs is None else out_crs
with rasterio.open(self.path) as inp:
inp_crs = inp.crs
out_bbox = bbox = box(*inp.bounds)
# If soucre and target CRSes differ, segmentize and reproject
if inp_crs != out_crs:
# estimate segmentize value (raster pixel size * tile size)
# and get reprojected bounding box
return reproject_geometry(segmentize_geometry(
bbox, inp.transform[0] * self.pyramid.tile_size),
src_crs=inp_crs,
dst_crs=out_crs)
else:
return out_bbox
def get_best_zoom_level(input_file, tile_pyramid_type):
"""
Determine the best base zoom level for a raster.
"Best" means the maximum zoom level where no oversampling has to be done.
Parameters
----------
input_file : path to raster file
tile_pyramid_type : ``TilePyramid`` projection (``geodetic`` or
``mercator``)
Returns
-------
zoom : integer
"""
tile_pyramid = TilePyramid(tile_pyramid_type)
with rasterio.open(input_file, "r") as src:
xmin, ymin, xmax, ymax = reproject_geometry(
segmentize_geometry(
box(src.bounds.left, src.bounds.bottom, src.bounds.right,
src.bounds.top),
get_segmentize_value(input_file, tile_pyramid)),
src_crs=src.crs,
dst_crs=tile_pyramid.crs).bounds
x_dif = xmax - xmin
y_dif = ymax - ymin
size = float(src.width + src.height)
avg_resolution = ((x_dif / float(src.width)) *
(float(src.width) / size) +
(y_dif / float(src.height)) *
(float(src.height) / size))
for zoom in range(0, 40):
if tile_pyramid.pixel_x_size(zoom) <= avg_resolution:
return zoom - 1