import tensorflow as tf
from niftynet.application.base_application import BaseApplication
from niftynet.contrib.segmentation_selective_sampler.sampler_selective import \
SelectiveSampler, Constraint
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_v2 import GridSampler
from niftynet.engine.windows_aggregator_grid import GridSamplesAggregator
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
SUPPORTED_INPUT = set(['image', 'label', 'weight', 'sampler'])
[docs]class SelectiveSampling(BaseApplication):
REQUIRED_CONFIG_SECTION = "SEGMENTATION"
def __init__(self, net_param, action_param, is_training):
super(SelectiveSampling, self).__init__()
tf.logging.info('starting segmentation application')
self.is_training = is_training
self.net_param = net_param
self.action_param = action_param
self.data_param = None
self.segmentation_param = None
self.SUPPORTED_SAMPLING = {
'selective': (self.initialise_selective_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
try:
reader_phase = self.action_param.dataset_to_infer
except AttributeError:
reader_phase = None
file_lists = data_partitioner.get_file_lists_by(
phase=reader_phase, action=self.action)
# 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(SUPPORTED_INPUT)
reader.initialise(data_param, task_param, file_list)
self.readers.append(reader)
else: # in the inference process use image input only
inference_reader = ImageReader(['image'])
inference_reader.initialise(data_param, task_param, file_lists[0])
self.readers = [inference_reader]
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_normaliser = None
if self.net_param.histogram_ref_file:
label_normaliser = DiscreteLabelNormalisationLayer(
image_name='label',
modalities=vars(task_param).get('label'),
model_filename=self.net_param.histogram_ref_file)
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:
normalisation_layers.append(label_normaliser)
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)
volume_padding_layer = [PadLayer(
image_name=SUPPORTED_INPUT,
border=self.net_param.volume_padding_size,
mode=self.net_param.volume_padding_mode,
pad_to=self.net_param.volume_padding_to_size)
]
for reader in self.readers:
reader.add_preprocessing_layers(
volume_padding_layer +
normalisation_layers +
augmentation_layers)
[docs] def initialise_selective_sampler(self):
# print("Initialisation ",
# self.segmentation_param.compulsory_labels,
# self.segmentation_param.proba_connect)
# print(self.segmentation_param.num_min_labels,
# self.segmentation_param.proba_connect)
selective_constraints = Constraint(
self.segmentation_param.compulsory_labels,
self.segmentation_param.min_sampling_ratio,
self.segmentation_param.min_numb_labels,
self.segmentation_param.proba_connect)
self.sampler = [[
SelectiveSampler(
reader=reader,
data_param=self.data_param,
batch_size=self.net_param.batch_size,
windows_per_image=self.action_param.sample_per_volume,
constraint=selective_constraints,
random_windows_per_image=self.segmentation_param.rand_samples,
queue_length=self.net_param.queue_length)
for reader in self.readers]]
[docs] def initialise_grid_sampler(self):
self.sampler = [[GridSampler(
reader=reader,
window_sizes=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_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_sampler(self):
if self.is_training:
self.SUPPORTED_SAMPLING['selective'][0]()
else:
self.SUPPORTED_SAMPLING['selective'][1]()
[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 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 = 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)
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='dice_loss',
average_over_devices=False, collection=CONSOLE)
outputs_collector.add_to_collection(
var=data_loss, name='dice_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)
else:
# 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)
init_aggregator = \
self.SUPPORTED_SAMPLING[self.net_param.window_sampling][2]
init_aggregator()
[docs] def interpret_output(self, batch_output):
if not self.is_training:
return self.output_decoder.decode_batch(
{'window_image': batch_output['window']},
batch_output['location'])
return True
