def get_image_bounds(image_file: str) -> str:
"""Loads the boundaries from an image file
Arguments:
image_file: path to the image to load the bounds from
Return:
Returns the GEOJSON of the bounds if they could be loaded and converted (if necessary).
None is returned if the bounds are loaded or can't be converted
"""
# If the file has a geo shape we store it for clipping
bounds = image_get_geobounds(image_file)
epsg = get_epsg(image_file)
if bounds[0] != np.nan:
ring = ogr.Geometry(ogr.wkbLinearRing)
ring.AddPoint(bounds[2], bounds[1]) # Upper left
ring.AddPoint(bounds[3], bounds[1]) # Upper right
ring.AddPoint(bounds[3], bounds[0]) # lower right
ring.AddPoint(bounds[2], bounds[0]) # lower left
ring.AddPoint(bounds[2], bounds[1]) # Closing the polygon
poly = ogr.Geometry(ogr.wkbPolygon)
poly.AddGeometry(ring)
ref_sys = osr.SpatialReference()
if ref_sys.ImportFromEPSG(int(epsg)) == ogr.OGRERR_NONE:
poly.AssignSpatialReference(ref_sys)
return geometry_to_geojson(poly)
logging.warning("Failed to import EPSG %s for image file %s", str(epsg), image_file)
return None
def clip_raster_intersection(file_path: str, file_bounds: str,
plot_bounds: str,
out_file: str) -> Optional[int]:
"""Clips the raster to the intersection of the file bounds and plot bounds
Arguments:
file_path: the path to the source file
file_bounds: the geometric boundary of the source file as JSON
plot_bounds: the geometric boundary of the plot to clip to as JSON
out_file: the path to store the clipped image
Return:
The number of pixels in the new image, or None if no pixels were saved
Notes:
Assumes the boundaries are in the same coordinate system
Exceptions:
Raises RuntimeError if the polygons are invalid
"""
logging.debug(
"Clip to intersect of plot boundary: File: '%s' '%s' Plot: '%s'",
file_path, str(file_bounds), str(plot_bounds))
try:
file_poly = ogr.CreateGeometryFromJson(str(file_bounds))
plot_poly = ogr.CreateGeometryFromJson(str(plot_bounds))
if not file_poly or not plot_poly:
logging.error(
"Invalid polygon specified for clip_raster_intersection: File: '%s' plot: '%s'",
str(file_bounds), str(plot_bounds))
raise RuntimeError(
"One or more invalid polygons specified when clipping raster"
)
intersection = file_poly.Intersection(plot_poly)
if not intersection or not intersection.Area():
logging.info("File does not intersect plot boundary: %s",
file_path)
return None
# Make sure we pass a multipolygon down to the tuple converter
if intersection.GetGeometryName().startswith('MULTI'):
multi_polygon = intersection
else:
multi_polygon = ogr.Geometry(ogr.wkbMultiPolygon)
multi_polygon.AddGeometry(intersection)
# Proceed to clip to the intersection
tuples = __internal__.geojson_to_tuples(
geometry_to_geojson(multi_polygon))
return clip_raster(file_path,
tuples,
out_path=out_file,
compress=True)
except Exception as ex:
logging.exception(
"Exception caught while clipping image to plot intersection")
raise ex
def get_image_bounds_json(file_path: str,
default_epsg: int = None) -> Optional[str]:
"""Loads the boundaries of the image file and returns the GeoJSON
representing the bounds (including EPSG code)
Arguments:
file_path: path to the file from which to load the bounds
default_epsg: the default EPSG to assume if a file has a boundary but not a coordinate system
Return:
Returns the JSON representing the image boundary, or None if the
bounds could not be loaded
Notes:
If a file doesn't have a coordinate system and a default epsg is specified, the
return JSON will use the default_epsg.
If a file doesn't have a coordinate system and there isn't a default epsg specified, the boundary
of the image is not returned (None) and a warning is logged.
"""
# Get the bounds (if they exist)
bounds = image_get_geobounds(file_path)
if bounds[0] == np.nan:
return None
epsg = get_epsg(file_path)
if epsg is None:
if default_epsg:
epsg = default_epsg
else:
logging.warning(
"Files does not have a coordinate system defined and no default was specified: '%s'",
file_path)
return None
ring = ogr.Geometry(ogr.wkbLinearRing)
ring.AddPoint(bounds[2], bounds[1]) # Upper left
ring.AddPoint(bounds[3], bounds[1]) # Upper right
ring.AddPoint(bounds[3], bounds[0]) # lower right
ring.AddPoint(bounds[2], bounds[0]) # lower left
ring.AddPoint(bounds[2], bounds[1]) # Closing the polygon
poly = ogr.Geometry(ogr.wkbPolygon)
poly.AddGeometry(ring)
ref_sys = osr.SpatialReference()
if ref_sys.ImportFromEPSG(int(epsg)) == ogr.OGRERR_NONE:
poly.AssignSpatialReference(ref_sys)
return geometry_to_geojson(poly)
logging.error("Failed to import EPSG %s for image file %s", str(epsg),
file_path)
return None
def get_las_extents(file_path: str,
default_epsg: int = None) -> Optional[str]:
"""Calculate the extent of the given las file and return as GeoJSON.
Arguments:
file_path: path to the file from which to load the bounds
default_epsg: the default EPSG to assume if a file has a boundary but not a coordinate system
Return:
Returns the JSON representing the image boundary, or None if the
bounds could not be loaded
Notes:
If a file doesn't have a coordinate system and a default epsg is specified, the
return JSON will use the default_epsg.
If a file doesn't have a coordinate system and there isn't a default epsg specified, the boundary
of the image is not returned (None) and a warning is logged.
"""
# Get the bounds and the EPSG code
las_info = liblas.file.File(file_path, mode='r')
min_bound = las_info.header.min
max_bound = las_info.header.max
epsg = __internal__.get_las_epsg_from_header(las_info.header)
if epsg is None:
if default_epsg is not None:
epsg = default_epsg
else:
logging.warning(
"Unable to find EPSG and not default is specified for file '%s'",
file_path)
return None
ring = ogr.Geometry(ogr.wkbLinearRing)
ring.AddPoint(min_bound[1], min_bound[0]) # Upper left
ring.AddPoint(min_bound[1], max_bound[0]) # Upper right
ring.AddPoint(max_bound[1], max_bound[0]) # lower right
ring.AddPoint(max_bound[1], min_bound[0]) # lower left
ring.AddPoint(min_bound[1], min_bound[0]) # Closing the polygon
poly = ogr.Geometry(ogr.wkbPolygon)
poly.AddGeometry(ring)
ref_sys = osr.SpatialReference()
if ref_sys.ImportFromEPSG(int(epsg)) == ogr.OGRERR_NONE:
poly.AssignSpatialReference(ref_sys)
return geometry_to_geojson(poly)
logging.error("Failed to import EPSG %s for las file %s", str(epsg),
file_path)
return None