def _preprocess(self, image_filename, output_dir, labelling=True):
"""Resize/crop then save the training & label images
Parameters
----------
datadir : str
image_filaname : str
labelling : boolean
Returns
-------
dict
Key/values with the filenames and label ids
"""
# open original images
img_in = Image.open(image_filename)
# resize images
# (self.image_size*larger_size or larger_size*self.image_size)
img_in = utils.resize_image(img_in, self.image_size)
# crop images to get self.image_size*self.image_size dimensions
crop_pix = np.random.randint(0, 1 + max(img_in.size) - self.image_size)
final_img_in = utils.mono_crop_image(img_in, crop_pix)
# save final image
new_in_filename = os.path.join(output_dir, "images",
os.path.basename(image_filename))
final_img_in.save(new_in_filename)
# label_filename vs label image
if labelling:
label_filename = image_filename.replace("images/", "labels/")
label_filename = label_filename.replace(".jpg", ".png")
img_out = Image.open(label_filename)
img_out = utils.resize_image(img_out, self.image_size)
img_out = utils.mono_crop_image(img_out, crop_pix)
# aggregate some labels
img_out = self.group_image_label(img_out)
labels = utils.build_labels(img_out,
self.label_ids,
dataset="mapillary")
new_out_filename = os.path.join(output_dir, "labels",
os.path.basename(label_filename))
label_out = np.array(img_out)
final_img_out = utils.build_image_from_config(
label_out, self.label_info)
final_img_out.save(new_out_filename)
else:
new_out_filename = None
labels = {i: 0 for i in range(self.get_nb_labels())}
return {
"raw_filename": image_filename,
"image_filename": new_in_filename,
"label_filename": new_out_filename,
"labels": labels,
}
def _preprocess_for_training(self, image_filename, output_dir, nb_images):
"""Resize/crop then save the training & label images
Parameters
----------
image_filename : str
Full path towards the image on the disk
output_dir : str
Output path where preprocessed image must be saved
Returns
-------
dict
Key/values with the filenames and label ids
"""
raster = gdal.Open(image_filename)
raw_img_width = raster.RasterXSize
raw_img_height = raster.RasterYSize
image_data = raster.ReadAsArray()
image_data = np.swapaxes(image_data, 0, 2)
result_dicts = []
logger.info(
"Image filename: %s, size: (%s, %s)",
image_filename.split("/")[-1], raw_img_width, raw_img_height
)
label_filename = image_filename.replace("images", "gt")
label_raster = gdal.Open(label_filename)
labels = label_raster.ReadAsArray()
nb_attempts = 0
image_counter = 0
empty_image_counter = 0
while image_counter < nb_images and nb_attempts < 2 * nb_images:
# randomly pick an image
x = np.random.randint(0, raw_img_width - self.image_size)
y = np.random.randint(0, raw_img_height - self.image_size)
tile_data = image_data[
x:(x + self.image_size), y:(y + self.image_size)
]
tile_image = Image.fromarray(tile_data)
mask = labels[
x:(x + self.image_size), y:(y + self.image_size)
]
label_dict = utils.build_labels(
mask, range(self.get_nb_labels()), "aerial"
)
labelled_image = utils.build_image_from_config(mask, self.labels)
if np.unique(mask).shape[0] > 1:
tiled_results = self._serialize(
tile_image,
labelled_image,
label_dict,
image_filename,
output_dir,
x,
y,
"nw",
)
if tiled_results:
result_dicts.append(tiled_results)
image_counter += 1
tile_image_ne = tile_image.transpose(Image.FLIP_LEFT_RIGHT)
labelled_image_ne = labelled_image.transpose(
Image.FLIP_LEFT_RIGHT
)
tiled_results_ne = self._serialize(
tile_image_ne,
labelled_image_ne,
label_dict,
image_filename,
output_dir,
x,
y,
"ne",
)
if tiled_results_ne:
result_dicts.append(tiled_results_ne)
image_counter += 1
tile_image_sw = tile_image.transpose(Image.FLIP_TOP_BOTTOM)
labelled_image_sw = labelled_image.transpose(
Image.FLIP_TOP_BOTTOM
)
tiled_results_sw = self._serialize(
tile_image_sw,
labelled_image_sw,
label_dict,
image_filename,
output_dir,
x,
y,
"sw",
)
if tiled_results_sw:
result_dicts.append(tiled_results_sw)
image_counter += 1
tile_image_se = tile_image_sw.transpose(Image.FLIP_LEFT_RIGHT)
labelled_image_se = labelled_image_sw.transpose(
Image.FLIP_LEFT_RIGHT
)
tiled_results_se = self._serialize(
tile_image_se,
labelled_image_se,
label_dict,
image_filename,
output_dir,
x,
y,
"se",
)
if tiled_results_se:
result_dicts.append(tiled_results_se)
image_counter += 1
del tile_image_se, tile_image_sw, tile_image_ne
del labelled_image_se, labelled_image_sw, labelled_image_ne
else:
if empty_image_counter < 0.1 * nb_images:
tiled_results = self._serialize(
tile_image,
labelled_image,
label_dict,
image_filename,
output_dir,
x,
y,
"nw",
)
if tiled_results:
result_dicts.append(tiled_results)
image_counter += 1
empty_image_counter += 1
nb_attempts += 1
del raster
logger.info(
"Generate %s images after %s attempts.", image_counter, nb_attempts
)
return result_dicts
def _preprocess_for_training(self, image_filename, output_dir, nb_images):
"""Resize/crop then save the training & label images
Parameters
----------
image_filename : str
Full path towards the image on the disk
output_dir : str
Output path where preprocessed image must be saved
Returns
-------
dict
Key/values with the filenames and label ids
"""
raster = gdal.Open(image_filename)
raw_img_width = raster.RasterXSize
raw_img_height = raster.RasterYSize
image_data = raster.ReadAsArray()
image_data = np.swapaxes(image_data, 0, 2)
result_dicts = []
logger.info(
"Image filename: %s, size: (%s, %s)",
image_filename.split("/")[-1], raw_img_width, raw_img_height
)
label_filename = image_filename.replace("images", "labels").replace(
".tif", ".geojson"
)
labels = gpd.read_file(label_filename)
labels = labels.loc[~labels.geometry.isna(), ["condition", "geometry"]]
none_mask = [lc is None for lc in labels.condition]
labels.loc[none_mask, "condition"] = "Complete"
nb_attempts = 0
image_counter = 0
empty_image_counter = 0
while image_counter < nb_images and nb_attempts < 2 * nb_images:
# randomly pick an image
x = np.random.randint(0, raw_img_width - self.image_size)
y = np.random.randint(0, raw_img_height - self.image_size)
tile_data = image_data[
x:(x + self.image_size), y:(y + self.image_size)
]
tile_image = Image.fromarray(tile_data)
raster_features = geometries.get_image_features(raster)
tile_items = geometries.extract_tile_items(
raster_features, labels, x, y, self.image_size, self.image_size
)
mask = self.load_mask(tile_items, raster_features, x, y)
label_dict = utils.build_labels(
mask, range(self.get_nb_labels()), "tanzania"
)
labelled_image = utils.build_image_from_config(mask, self.labels)
if len(tile_items) > 0:
tiled_results = self._serialize(
tile_image,
labelled_image,
label_dict,
image_filename,
output_dir,
x,
y,
"nw",
)
if tiled_results:
result_dicts.append(tiled_results)
image_counter += 1
tile_image_ne = tile_image.transpose(Image.FLIP_LEFT_RIGHT)
labelled_image_ne = labelled_image.transpose(
Image.FLIP_LEFT_RIGHT
)
tiled_results_ne = self._serialize(
tile_image_ne,
labelled_image_ne,
label_dict,
image_filename,
output_dir,
x,
y,
"ne",
)
if tiled_results_ne:
result_dicts.append(tiled_results_ne)
image_counter += 1
tile_image_sw = tile_image.transpose(Image.FLIP_TOP_BOTTOM)
labelled_image_sw = labelled_image.transpose(
Image.FLIP_TOP_BOTTOM
)
tiled_results_sw = self._serialize(
tile_image_sw,
labelled_image_sw,
label_dict,
image_filename,
output_dir,
x,
y,
"sw",
)
if tiled_results_sw:
result_dicts.append(tiled_results_sw)
image_counter += 1
tile_image_se = tile_image_sw.transpose(Image.FLIP_LEFT_RIGHT)
labelled_image_se = labelled_image_sw.transpose(
Image.FLIP_LEFT_RIGHT
)
tiled_results_se = self._serialize(
tile_image_se,
labelled_image_se,
label_dict,
image_filename,
output_dir,
x,
y,
"se",
)
if tiled_results_se:
result_dicts.append(tiled_results_se)
image_counter += 1
del tile_image_se, tile_image_sw, tile_image_ne
del labelled_image_se, labelled_image_sw, labelled_image_ne
else:
if empty_image_counter < 0.1 * nb_images:
tiled_results = self._serialize(
tile_image,
labelled_image,
label_dict,
image_filename,
output_dir,
x,
y,
"nw",
)
if tiled_results:
result_dicts.append(tiled_results)
image_counter += 1
empty_image_counter += 1
nb_attempts += 1
del raster
logger.info(
"Generate %s images after %s attempts.", image_counter, nb_attempts
)
return result_dicts
def _preprocess_tile(self,
x,
y,
image_filename,
output_dir,
raster,
labels=None):
"""Preprocess one single tile built from `image_filename`, with respect
to pixel coordinates `(x, y)`
Parameters
----------
x : int
Horizontal pixel coordinate (*i.e.* west bound)
y : int
Vertical pixel coordinate (*i.e.* north bound)
image_filename : str
Full path towards the image on the disk
output_dir : str
Output path where preprocessed image must be saved
raster : osgeo.gdal.Dataset
Original georeferenced raster
labels : geopandas.GeoDataFrame
Raw image labels (*i.e.* georeferenced buildings)
Returns
-------
dict
Key/values with the filenames and label ids
"""
basename_decomp = os.path.splitext(os.path.basename(image_filename))
img_id_str = (str(self.image_size) + '_' + str(self.image_size) + '_' +
str(x) + '_' + str(y))
new_in_filename = (basename_decomp[0] + '_' + img_id_str + ".png")
new_in_path = os.path.join(output_dir, 'images', new_in_filename)
gdal.Translate(new_in_path,
raster,
format="PNG",
srcWin=[x, y, self.image_size, self.image_size])
if not labels is None:
raster_features = get_image_features(raster)
tile_items = extract_tile_items(raster_features,
labels,
x,
y,
self.image_size,
self.image_size,
tile_srid=32737)
out_labelname = (new_in_path.replace("images", "labels"))
mask = self.load_mask(tile_items, raster_features, x, y)
label_dict = utils.build_labels(mask, range(self.get_nb_labels()),
"tanzania")
labelled_image = utils.build_image_from_config(mask, self.labels)
labelled_image.save(out_labelname)
return {
"raw_filename": image_filename,
"image_filename": new_in_path,
"label_filename": out_labelname,
"labels": label_dict
}
else:
return {
"raw_filename": image_filename,
"image_filename": new_in_path
}