import tensorflow as tf
from niftynet.application.base_application import BaseApplication
from niftynet.engine.application_factory import \
ApplicationNetFactory, InitializerFactory, OptimiserFactory
from niftynet.engine.application_variables import \
CONSOLE, NETWORK_OUTPUT, TF_SUMMARIES
from niftynet.engine.sampler_grid import GridSampler
from niftynet.engine.sampler_resize import ResizeSampler
from niftynet.engine.sampler_uniform import UniformSampler
from niftynet.engine.sampler_weighted import WeightedSampler
from niftynet.engine.sampler_balanced import BalancedSampler
from niftynet.engine.windows_aggregator_grid import GridSamplesAggregator
from niftynet.engine.windows_aggregator_resize import ResizeSamplesAggregator
from niftynet.io.image_reader import ImageReader
from niftynet.layer.binary_masking import BinaryMaskingLayer
from niftynet.layer.discrete_label_normalisation import \
DiscreteLabelNormalisationLayer
from niftynet.layer.histogram_normalisation import \
HistogramNormalisationLayer
from niftynet.layer.loss_segmentation import LossFunction
from niftynet.layer.mean_variance_normalisation import \
MeanVarNormalisationLayer
from niftynet.layer.pad import PadLayer
from niftynet.layer.post_processing import PostProcessingLayer
from niftynet.layer.rand_flip import RandomFlipLayer
from niftynet.layer.rand_rotation import RandomRotationLayer
from niftynet.layer.rand_spatial_scaling import RandomSpatialScalingLayer
from niftynet.evaluation.segmentation_evaluator import SegmentationEvaluator
from niftynet.layer.rand_elastic_deform import RandomElasticDeformationLayer
SUPPORTED_INPUT = set(['image', 'label', 'weight', 'sampler', 'inferred'])
[docs]class SegmentationApplication(BaseApplication):
REQUIRED_CONFIG_SECTION = "SEGMENTATION"
def __init__(self, net_param, action_param, action):
super(SegmentationApplication, self).__init__()
tf.logging.info('starting segmentation application')
self.action = action
self.net_param = net_param
self.action_param = action_param
self.data_param = None
self.segmentation_param = None
self.SUPPORTED_SAMPLING = {
'uniform': (self.initialise_uniform_sampler,
self.initialise_grid_sampler,
self.initialise_grid_aggregator),
'weighted': (self.initialise_weighted_sampler,
self.initialise_grid_sampler,
self.initialise_grid_aggregator),
'resize': (self.initialise_resize_sampler,
self.initialise_resize_sampler,
self.initialise_resize_aggregator),
'balanced': (self.initialise_balanced_sampler,
self.initialise_grid_sampler,
self.initialise_grid_aggregator),
}
[docs] def initialise_dataset_loader(
self, data_param=None, task_param=None, data_partitioner=None):
self.data_param = data_param
self.segmentation_param = task_param
file_lists = self.get_file_lists(data_partitioner)
# read each line of csv files into an instance of Subject
if self.is_training:
self.readers = []
for file_list in file_lists:
reader = ImageReader({'image', 'label', 'weight', 'sampler'})
reader.initialise(data_param, task_param, file_list)
self.readers.append(reader)
elif self.is_inference:
# in the inference process use image input only
inference_reader = ImageReader({'image'})
file_list = data_partitioner.inference_files
inference_reader.initialise(data_param, task_param, file_list)
self.readers = [inference_reader]
elif self.is_evaluation:
file_list = data_partitioner.inference_files
reader = ImageReader({'image', 'label', 'inferred'})
reader.initialise(data_param, task_param, file_list)
self.readers = [reader]
else:
raise ValueError('Action `{}` not supported. Expected one of {}'
.format(self.action, self.SUPPORTED_ACTIONS))
foreground_masking_layer = None
if self.net_param.normalise_foreground_only:
foreground_masking_layer = BinaryMaskingLayer(
type_str=self.net_param.foreground_type,
multimod_fusion=self.net_param.multimod_foreground_type,
threshold=0.0)
mean_var_normaliser = MeanVarNormalisationLayer(
image_name='image', binary_masking_func=foreground_masking_layer)
histogram_normaliser = None
if self.net_param.histogram_ref_file:
histogram_normaliser = HistogramNormalisationLayer(
image_name='image',
modalities=vars(task_param).get('image'),
model_filename=self.net_param.histogram_ref_file,
binary_masking_func=foreground_masking_layer,
norm_type=self.net_param.norm_type,
cutoff=self.net_param.cutoff,
name='hist_norm_layer')
label_normalisers = None
if self.net_param.histogram_ref_file and \
task_param.label_normalisation:
label_normalisers = [DiscreteLabelNormalisationLayer(
image_name='label',
modalities=vars(task_param).get('label'),
model_filename=self.net_param.histogram_ref_file)]
if self.is_evaluation:
label_normalisers.append(
DiscreteLabelNormalisationLayer(
image_name='inferred',
modalities=vars(task_param).get('inferred'),
model_filename=self.net_param.histogram_ref_file))
label_normalisers[-1].key = label_normalisers[0].key
normalisation_layers = []
if self.net_param.normalisation:
normalisation_layers.append(histogram_normaliser)
if self.net_param.whitening:
normalisation_layers.append(mean_var_normaliser)
if task_param.label_normalisation and \
(self.is_training or not task_param.output_prob):
normalisation_layers.extend(label_normalisers)
augmentation_layers = []
if self.is_training:
if self.action_param.random_flipping_axes != -1:
augmentation_layers.append(RandomFlipLayer(
flip_axes=self.action_param.random_flipping_axes))
if self.action_param.scaling_percentage:
augmentation_layers.append(RandomSpatialScalingLayer(
min_percentage=self.action_param.scaling_percentage[0],
max_percentage=self.action_param.scaling_percentage[1]))
if self.action_param.rotation_angle or \
self.action_param.rotation_angle_x or \
self.action_param.rotation_angle_y or \
self.action_param.rotation_angle_z:
rotation_layer = RandomRotationLayer()
if self.action_param.rotation_angle:
rotation_layer.init_uniform_angle(
self.action_param.rotation_angle)
else:
rotation_layer.init_non_uniform_angle(
self.action_param.rotation_angle_x,
self.action_param.rotation_angle_y,
self.action_param.rotation_angle_z)
augmentation_layers.append(rotation_layer)
# add deformation layer
if self.action_param.do_elastic_deformation:
spatial_rank = list(self.readers[0].spatial_ranks.values())[0]
augmentation_layers.append(RandomElasticDeformationLayer(
spatial_rank=spatial_rank,
num_controlpoints=self.action_param.num_ctrl_points,
std_deformation_sigma=self.action_param.deformation_sigma,
proportion_to_augment=self.action_param.proportion_to_deform))
volume_padding_layer = []
if self.net_param.volume_padding_size:
volume_padding_layer.append(PadLayer(
image_name=SUPPORTED_INPUT,
border=self.net_param.volume_padding_size))
# only add augmentation to first reader (not validation reader)
self.readers[0].add_preprocessing_layers(
volume_padding_layer +
normalisation_layers +
augmentation_layers)
for reader in self.readers[1:]:
reader.add_preprocessing_layers(
volume_padding_layer +
normalisation_layers)
[docs] def initialise_weighted_sampler(self):
self.sampler = [[WeightedSampler(
reader=reader,
data_param=self.data_param,
batch_size=self.net_param.batch_size,
windows_per_image=self.action_param.sample_per_volume,
queue_length=self.net_param.queue_length) for reader in
self.readers]]
[docs] def initialise_resize_sampler(self):
self.sampler = [[ResizeSampler(
reader=reader,
data_param=self.data_param,
batch_size=self.net_param.batch_size,
shuffle_buffer=self.is_training,
queue_length=self.net_param.queue_length) for reader in
self.readers]]
[docs] def initialise_grid_sampler(self):
self.sampler = [[GridSampler(
reader=reader,
data_param=self.data_param,
batch_size=self.net_param.batch_size,
spatial_window_size=self.action_param.spatial_window_size,
window_border=self.action_param.border,
queue_length=self.net_param.queue_length) for reader in
self.readers]]
[docs] def initialise_balanced_sampler(self):
self.sampler = [[BalancedSampler(
reader=reader,
data_param=self.data_param,
batch_size=self.net_param.batch_size,
windows_per_image=self.action_param.sample_per_volume,
queue_length=self.net_param.queue_length) for reader in
self.readers]]
[docs] def initialise_grid_aggregator(self):
self.output_decoder = GridSamplesAggregator(
image_reader=self.readers[0],
output_path=self.action_param.save_seg_dir,
window_border=self.action_param.border,
interp_order=self.action_param.output_interp_order)
[docs] def initialise_resize_aggregator(self):
self.output_decoder = ResizeSamplesAggregator(
image_reader=self.readers[0],
output_path=self.action_param.save_seg_dir,
window_border=self.action_param.border,
interp_order=self.action_param.output_interp_order)
[docs] def initialise_sampler(self):
if self.is_training:
self.SUPPORTED_SAMPLING[self.net_param.window_sampling][0]()
elif self.is_inference:
self.SUPPORTED_SAMPLING[self.net_param.window_sampling][1]()
[docs] def initialise_aggregator(self):
self.SUPPORTED_SAMPLING[self.net_param.window_sampling][2]()
[docs] def initialise_network(self):
w_regularizer = None
b_regularizer = None
reg_type = self.net_param.reg_type.lower()
decay = self.net_param.decay
if reg_type == 'l2' and decay > 0:
from tensorflow.contrib.layers.python.layers import regularizers
w_regularizer = regularizers.l2_regularizer(decay)
b_regularizer = regularizers.l2_regularizer(decay)
elif reg_type == 'l1' and decay > 0:
from tensorflow.contrib.layers.python.layers import regularizers
w_regularizer = regularizers.l1_regularizer(decay)
b_regularizer = regularizers.l1_regularizer(decay)
self.net = ApplicationNetFactory.create(self.net_param.name)(
num_classes=self.segmentation_param.num_classes,
w_initializer=InitializerFactory.get_initializer(
name=self.net_param.weight_initializer),
b_initializer=InitializerFactory.get_initializer(
name=self.net_param.bias_initializer),
w_regularizer=w_regularizer,
b_regularizer=b_regularizer,
acti_func=self.net_param.activation_function)
[docs] def connect_data_and_network(self,
outputs_collector=None,
gradients_collector=None):
# def data_net(for_training):
# with tf.name_scope('train' if for_training else 'validation'):
# sampler = self.get_sampler()[0][0 if for_training else -1]
# data_dict = sampler.pop_batch_op()
# image = tf.cast(data_dict['image'], tf.float32)
# return data_dict, self.net(image, is_training=for_training)
def switch_sampler(for_training):
with tf.name_scope('train' if for_training else 'validation'):
sampler = self.get_sampler()[0][0 if for_training else -1]
return sampler.pop_batch_op()
if self.is_training:
# if self.action_param.validation_every_n > 0:
# data_dict, net_out = tf.cond(tf.logical_not(self.is_validation),
# lambda: data_net(True),
# lambda: data_net(False))
# else:
# data_dict, net_out = data_net(True)
if self.action_param.validation_every_n > 0:
data_dict = tf.cond(tf.logical_not(self.is_validation),
lambda: switch_sampler(for_training=True),
lambda: switch_sampler(for_training=False))
else:
data_dict = switch_sampler(for_training=True)
image = tf.cast(data_dict['image'], tf.float32)
net_out = self.net(image, is_training=self.is_training)
with tf.name_scope('Optimiser'):
optimiser_class = OptimiserFactory.create(
name=self.action_param.optimiser)
self.optimiser = optimiser_class.get_instance(
learning_rate=self.action_param.lr)
loss_func = LossFunction(
n_class=self.segmentation_param.num_classes,
loss_type=self.action_param.loss_type,
softmax=self.segmentation_param.softmax)
data_loss = loss_func(
prediction=net_out,
ground_truth=data_dict.get('label', None),
weight_map=data_dict.get('weight', None))
reg_losses = tf.get_collection(
tf.GraphKeys.REGULARIZATION_LOSSES)
if self.net_param.decay > 0.0 and reg_losses:
reg_loss = tf.reduce_mean(
[tf.reduce_mean(reg_loss) for reg_loss in reg_losses])
loss = data_loss + reg_loss
else:
loss = data_loss
grads = self.optimiser.compute_gradients(loss)
# collecting gradients variables
gradients_collector.add_to_collection([grads])
# collecting output variables
outputs_collector.add_to_collection(
var=data_loss, name='loss',
average_over_devices=False, collection=CONSOLE)
outputs_collector.add_to_collection(
var=data_loss, name='loss',
average_over_devices=True, summary_type='scalar',
collection=TF_SUMMARIES)
# outputs_collector.add_to_collection(
# var=image*180.0, name='image',
# average_over_devices=False, summary_type='image3_sagittal',
# collection=TF_SUMMARIES)
# outputs_collector.add_to_collection(
# var=image, name='image',
# average_over_devices=False,
# collection=NETWORK_OUTPUT)
# outputs_collector.add_to_collection(
# var=tf.reduce_mean(image), name='mean_image',
# average_over_devices=False, summary_type='scalar',
# collection=CONSOLE)
elif self.is_inference:
# converting logits into final output for
# classification probabilities or argmax classification labels
data_dict = switch_sampler(for_training=False)
image = tf.cast(data_dict['image'], tf.float32)
net_out = self.net(image, is_training=self.is_training)
output_prob = self.segmentation_param.output_prob
num_classes = self.segmentation_param.num_classes
if output_prob and num_classes > 1:
post_process_layer = PostProcessingLayer(
'SOFTMAX', num_classes=num_classes)
elif not output_prob and num_classes > 1:
post_process_layer = PostProcessingLayer(
'ARGMAX', num_classes=num_classes)
else:
post_process_layer = PostProcessingLayer(
'IDENTITY', num_classes=num_classes)
net_out = post_process_layer(net_out)
outputs_collector.add_to_collection(
var=net_out, name='window',
average_over_devices=False, collection=NETWORK_OUTPUT)
outputs_collector.add_to_collection(
var=data_dict['image_location'], name='location',
average_over_devices=False, collection=NETWORK_OUTPUT)
self.initialise_aggregator()
[docs] def interpret_output(self, batch_output):
if self.is_inference:
return self.output_decoder.decode_batch(
batch_output['window'], batch_output['location'])
return True
[docs] def initialise_evaluator(self, eval_param):
self.eval_param = eval_param
self.evaluator = SegmentationEvaluator(self.readers[0],
self.segmentation_param,
eval_param)
[docs] def add_inferred_output(self, data_param, task_param):
return self.add_inferred_output_like(data_param, task_param, 'label')
