def add_roads_to_image(roads, image_path, extent):
""" This function could be moved to top level. """
# Get old image that needs indirect road damage visualized
image = Image.open(result_image['path'])
# Rasterize all roads that have indirect damage
size = image.size
geotransform = [
extent[0],
(extent[2] - extent[0]) / size[0],
0,
extent[3],
0,
(extent[1] - extent[3]) / size[1],
]
roadgrid = raster.get_mask(
roads=road_objects,
shape=image.size[::-1],
geo=(b'', geotransform),
)
# Paste it into the old image and overwrite the image file
rgba = np.uint8([[[0, 0, 0, 153]]]) * roadgrid.reshape(
roadgrid.shape[0], roadgrid.shape[1], 1
)
image_roads_rgb = Image.fromarray(rgba[:, :, 0:3])
image_roads_mask = Image.fromarray(rgba[:, :, 3])
image.paste(image_roads_rgb, None, image_roads_mask)
image.save(result_image['path'])
def get_roads_flooded_for_tile_and_code(code, depth, geo):
""" Return dict {road: flooded_m2}. """
area_per_pixel = raster.geo2cellsize(geo)
roads_flooded_for_tile_and_code = {}
roads = raster.get_roads(ROAD_GRIDCODE[code], geo, depth.shape)
for road in roads:
mask = raster.get_mask([road], depth.shape, geo)
flooded_m2 = (mask * area_per_pixel * np.greater(depth, 0)).sum()
if flooded_m2:
roads_flooded_for_tile_and_code[road.pk] = flooded_m2
return roads_flooded_for_tile_and_code
def add_roads_to_image(roads, image_path, extent):
"""Draw roads into an existing PNG."""
# Get old image that needs indirect road damage visualized
image = Image.open(image_path)
# Rasterize all roads that have indirect damage
size = image.size
geotransform = [
extent[0],
(extent[2] - extent[0]) / size[0],
0,
extent[3],
0,
(extent[1] - extent[3]) / size[1],
]
roadgrid = raster.get_mask(
roads=roads,
shape=image.size[::-1],
geo=(b'', geotransform),
)
# Paste it into the old image and overwrite the image file
rgba = np.uint8([[[0, 0, 0, 153]]]) * roadgrid.reshape(
roadgrid.shape[0], roadgrid.shape[1], 1
)
image_roads_rgb = Image.fromstring(
'RGB',
(rgba.shape[1], rgba.shape[0]),
rgba[:, :, 0:3].tostring(),
)
image_roads_mask = Image.fromstring(
'L',
(rgba.shape[1], rgba.shape[0]),
rgba[:, :, 3].tostring(),
)
image.paste(image_roads_rgb, None, image_roads_mask)
image.save(image_path)