def test_metrics_writer(self):
default_dir = os.path.join('.', 'runs')
shutil.rmtree(default_dir, ignore_errors=True)
with tempfile.TemporaryDirectory() as temp_dir:
# set up engine
def _train_func(engine, batch):
return batch + 1.0
engine = Engine(_train_func)
# set up dummy metric
@engine.on(Events.EPOCH_COMPLETED)
def _update_metric(engine):
current_metric = engine.state.metrics.get('acc', 0.1)
engine.state.metrics['acc'] = current_metric + 0.1
# set up testing handler
writer = SummaryWriter(log_dir=temp_dir)
stats_handler = TensorBoardStatsHandler(
writer,
output_transform=lambda x: {'loss': x * 2.0},
global_epoch_transform=lambda x: x * 3.0)
stats_handler.attach(engine)
engine.run(range(3), max_epochs=2)
# check logging output
self.assertTrue(len(glob.glob(temp_dir)) > 0)
self.assertTrue(not os.path.exists(default_dir))
def test_metrics_writer(self):
with tempfile.TemporaryDirectory() as tempdir:
# set up engine
def _train_func(engine, batch):
return [batch + 1.0]
engine = Engine(_train_func)
# set up dummy metric
@engine.on(Events.EPOCH_COMPLETED)
def _update_metric(engine):
current_metric = engine.state.metrics.get("acc", 0.1)
engine.state.metrics["acc"] = current_metric + 0.1
engine.state.test = current_metric
# set up testing handler
writer = SummaryWriter(log_dir=tempdir)
stats_handler = TensorBoardStatsHandler(
summary_writer=writer,
iteration_log=True,
epoch_log=False,
output_transform=lambda x: {"loss": x[0] * 2.0},
global_epoch_transform=lambda x: x * 3.0,
state_attributes=["test"],
)
stats_handler.attach(engine)
engine.run(range(3), max_epochs=2)
writer.close()
# check logging output
self.assertTrue(len(glob.glob(tempdir)) > 0)
def test_metrics_writer(self):
tempdir = tempfile.mkdtemp()
shutil.rmtree(tempdir, ignore_errors=True)
# set up engine
def _train_func(engine, batch):
return batch + 1.0
engine = Engine(_train_func)
# set up dummy metric
@engine.on(Events.EPOCH_COMPLETED)
def _update_metric(engine):
current_metric = engine.state.metrics.get("acc", 0.1)
engine.state.metrics["acc"] = current_metric + 0.1
# set up testing handler
writer = SummaryWriter(log_dir=tempdir)
stats_handler = TensorBoardStatsHandler(
writer, output_transform=lambda x: {"loss": x * 2.0}, global_epoch_transform=lambda x: x * 3.0
)
stats_handler.attach(engine)
engine.run(range(3), max_epochs=2)
# check logging output
self.assertTrue(os.path.exists(tempdir))
self.assertTrue(len(glob.glob(tempdir)) > 0)
shutil.rmtree(tempdir)
def train_handlers(self, context: Context):
handlers: List[Any] = []
# LR Scheduler
lr_scheduler = self.lr_scheduler_handler(context)
if lr_scheduler:
handlers.append(lr_scheduler)
if context.local_rank == 0:
handlers.extend([
StatsHandler(tag_name="train_loss",
output_transform=from_engine(["loss"],
first=True)),
TensorBoardStatsHandler(
log_dir=context.events_dir,
tag_name="train_loss",
output_transform=from_engine(["loss"], first=True),
),
])
if context.evaluator:
logger.info(
f"{context.local_rank} - Adding Validation to run every '{self._val_interval}' interval"
)
handlers.append(
ValidationHandler(self._val_interval,
validator=context.evaluator,
epoch_level=True))
return handlers
def val_handlers(self, context: Context):
val_handlers = [
StatsHandler(output_transform=lambda x: None),
TensorBoardStatsHandler(log_dir=context.events_dir,
output_transform=lambda x: None),
]
return val_handlers if context.local_rank == 0 else None
def test_metrics_print(self):
with tempfile.TemporaryDirectory() as tempdir:
# set up engine
def _train_func(engine, batch):
return batch + 1.0
engine = Engine(_train_func)
# set up dummy metric
@engine.on(Events.EPOCH_COMPLETED)
def _update_metric(engine):
current_metric = engine.state.metrics.get("acc", 0.1)
engine.state.metrics["acc"] = current_metric + 0.1
# set up testing handler
stats_handler = TensorBoardStatsHandler(log_dir=tempdir)
stats_handler.attach(engine)
engine.run(range(3), max_epochs=2)
# check logging output
self.assertTrue(len(glob.glob(tempdir)) > 0)
def run(self, date=None) -> str:
if date is not None:
now = date
else:
now = datetime.datetime.now()
datetime_string = now.strftime('%d/%m/%Y %H:%M:%S')
print(f'Training started: {datetime_string}')
now = datetime.datetime.now()
timedate_info = str(now).split(' ')[0] + '_' + str(now.strftime("%H:%M:%S")).replace(':', '-')
training_dir = os.path.join(self.out_dir, 'training')
if not os.path.exists(training_dir):
os.mkdir(training_dir)
self.output_dir = os.path.join(training_dir, self.out_name + '_' + timedate_info)
os.mkdir(self.output_dir)
self.validator.output_dir = self.output_dir
if self.summary_writer is None:
self.summary_writer = SummaryWriter(log_dir=self.output_dir)
if self.validator.summary_writer is None:
self.validator.summary_writer = self.summary_writer
handlers = [
MetricLogger(self.output_dir, validator=self.validator),
ValidationHandler(
validator=self.validator,
start=self.validation_epoch,
interval=self.validation_interval
),
StatsHandler(tag_name="loss", output_transform=lambda x: x["loss"]),
TensorBoardStatsHandler(
summary_writer=self.summary_writer,
tag_name="Loss",
output_transform=lambda x: x["loss"]
),
]
save_dict = { 'network': self.network, 'optimizer': self.optimizer }
if self.lr_scheduler is not None:
handlers.insert(0, LrScheduleHandler(lr_scheduler=self.lr_scheduler, print_lr=True))
save_dict['lr_scheduler'] = self.lr_scheduler
handlers.append(
CheckpointSaver(save_dir=self.output_dir, save_dict=save_dict, save_interval=1, n_saved=1)
)
self._register_handlers(handlers)
super().run()
return self.output_dir
def test_metrics_print(self):
default_dir = os.path.join('.', 'runs')
shutil.rmtree(default_dir, ignore_errors=True)
# set up engine
def _train_func(engine, batch):
return batch + 1.0
engine = Engine(_train_func)
# set up dummy metric
@engine.on(Events.EPOCH_COMPLETED)
def _update_metric(engine):
current_metric = engine.state.metrics.get('acc', 0.1)
engine.state.metrics['acc'] = current_metric + 0.1
# set up testing handler
stats_handler = TensorBoardStatsHandler()
stats_handler.attach(engine)
engine.run(range(3), max_epochs=2)
# check logging output
self.assertTrue(os.path.exists(default_dir))
shutil.rmtree(default_dir)
def run(self, global_epoch: int) -> None:
if global_epoch == 1:
handlers = [
StatsHandler(),
TensorBoardStatsHandler(
summary_writer=self.summary_writer
), #, output_transform=lambda x: None),
CheckpointSaver(save_dir=self.output_dir,
save_dict={"network": self.network},
save_key_metric=True),
MetricsSaver(save_dir=self.output_dir,
metrics=['Valid_AUC', 'Valid_ACC']),
self.early_stop_handler,
]
self._register_handlers(handlers)
return super().run(global_epoch=global_epoch)
def main():
monai.config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
# create a temporary directory and 40 random image, mask paris
tempdir = tempfile.mkdtemp()
print('generating synthetic data to {} (this may take a while)'.format(tempdir))
for i in range(40):
im, seg = create_test_image_3d(128, 128, 128, num_seg_classes=1)
n = nib.Nifti1Image(im, np.eye(4))
nib.save(n, os.path.join(tempdir, 'im%i.nii.gz' % i))
n = nib.Nifti1Image(seg, np.eye(4))
nib.save(n, os.path.join(tempdir, 'seg%i.nii.gz' % i))
images = sorted(glob(os.path.join(tempdir, 'im*.nii.gz')))
segs = sorted(glob(os.path.join(tempdir, 'seg*.nii.gz')))
# define transforms for image and segmentation
train_imtrans = Compose([
ScaleIntensity(),
AddChannel(),
RandSpatialCrop((96, 96, 96), random_size=False),
ToTensor()
])
train_segtrans = Compose([
AddChannel(),
RandSpatialCrop((96, 96, 96), random_size=False),
ToTensor()
])
val_imtrans = Compose([
ScaleIntensity(),
AddChannel(),
Resize((96, 96, 96)),
ToTensor()
])
val_segtrans = Compose([
AddChannel(),
Resize((96, 96, 96)),
ToTensor()
])
# define nifti dataset, data loader
check_ds = NiftiDataset(images, segs, transform=train_imtrans, seg_transform=train_segtrans)
check_loader = DataLoader(check_ds, batch_size=10, num_workers=2, pin_memory=torch.cuda.is_available())
im, seg = monai.utils.misc.first(check_loader)
print(im.shape, seg.shape)
# create a training data loader
train_ds = NiftiDataset(images[:20], segs[:20], transform=train_imtrans, seg_transform=train_segtrans)
train_loader = DataLoader(train_ds, batch_size=5, shuffle=True, num_workers=8, pin_memory=torch.cuda.is_available())
# create a validation data loader
val_ds = NiftiDataset(images[-20:], segs[-20:], transform=val_imtrans, seg_transform=val_segtrans)
val_loader = DataLoader(val_ds, batch_size=5, num_workers=8, pin_memory=torch.cuda.is_available())
# create UNet, DiceLoss and Adam optimizer
net = monai.networks.nets.UNet(
dimensions=3,
in_channels=1,
out_channels=1,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
)
loss = monai.losses.DiceLoss(do_sigmoid=True)
lr = 1e-3
opt = torch.optim.Adam(net.parameters(), lr)
device = torch.device('cuda:0')
# ignite trainer expects batch=(img, seg) and returns output=loss at every iteration,
# user can add output_transform to return other values, like: y_pred, y, etc.
trainer = create_supervised_trainer(net, opt, loss, device, False)
# adding checkpoint handler to save models (network params and optimizer stats) during training
checkpoint_handler = ModelCheckpoint('./runs/', 'net', n_saved=10, require_empty=False)
trainer.add_event_handler(event_name=Events.EPOCH_COMPLETED,
handler=checkpoint_handler,
to_save={'net': net, 'opt': opt})
# StatsHandler prints loss at every iteration and print metrics at every epoch,
# we don't set metrics for trainer here, so just print loss, user can also customize print functions
# and can use output_transform to convert engine.state.output if it's not a loss value
train_stats_handler = StatsHandler(name='trainer')
train_stats_handler.attach(trainer)
# TensorBoardStatsHandler plots loss at every iteration and plots metrics at every epoch, same as StatsHandler
train_tensorboard_stats_handler = TensorBoardStatsHandler()
train_tensorboard_stats_handler.attach(trainer)
validation_every_n_epochs = 1
# Set parameters for validation
metric_name = 'Mean_Dice'
# add evaluation metric to the evaluator engine
val_metrics = {metric_name: MeanDice(add_sigmoid=True, to_onehot_y=False)}
# ignite evaluator expects batch=(img, seg) and returns output=(y_pred, y) at every iteration,
# user can add output_transform to return other values
evaluator = create_supervised_evaluator(net, val_metrics, device, True)
@trainer.on(Events.EPOCH_COMPLETED(every=validation_every_n_epochs))
def run_validation(engine):
evaluator.run(val_loader)
# add early stopping handler to evaluator
early_stopper = EarlyStopping(patience=4,
score_function=stopping_fn_from_metric(metric_name),
trainer=trainer)
evaluator.add_event_handler(event_name=Events.EPOCH_COMPLETED, handler=early_stopper)
# add stats event handler to print validation stats via evaluator
val_stats_handler = StatsHandler(
name='evaluator',
output_transform=lambda x: None, # no need to print loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.epoch) # fetch global epoch number from trainer
val_stats_handler.attach(evaluator)
# add handler to record metrics to TensorBoard at every validation epoch
val_tensorboard_stats_handler = TensorBoardStatsHandler(
output_transform=lambda x: None, # no need to plot loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.epoch) # fetch global epoch number from trainer
val_tensorboard_stats_handler.attach(evaluator)
# add handler to draw the first image and the corresponding label and model output in the last batch
# here we draw the 3D output as GIF format along Depth axis, at every validation epoch
val_tensorboard_image_handler = TensorBoardImageHandler(
batch_transform=lambda batch: (batch[0], batch[1]),
output_transform=lambda output: predict_segmentation(output[0]),
global_iter_transform=lambda x: trainer.state.epoch
)
evaluator.add_event_handler(event_name=Events.EPOCH_COMPLETED, handler=val_tensorboard_image_handler)
train_epochs = 30
state = trainer.run(train_loader, train_epochs)
shutil.rmtree(tempdir)
def main(tempdir):
monai.config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
################################ DATASET ################################
# create a temporary directory and 40 random image, mask pairs
print(f"generating synthetic data to {tempdir} (this may take a while)")
for i in range(40):
im, seg = create_test_image_3d(128, 128, 128, num_seg_classes=1, channel_dim=-1)
n = nib.Nifti1Image(im, np.eye(4))
nib.save(n, os.path.join(tempdir, f"img{i:d}.nii.gz"))
n = nib.Nifti1Image(seg, np.eye(4))
nib.save(n, os.path.join(tempdir, f"seg{i:d}.nii.gz"))
images = sorted(glob(os.path.join(tempdir, "img*.nii.gz")))
segs = sorted(glob(os.path.join(tempdir, "seg*.nii.gz")))
train_files = [{"image": img, "label": seg} for img, seg in zip(images[:20], segs[:20])]
val_files = [{"image": img, "label": seg} for img, seg in zip(images[-20:], segs[-20:])]
# define transforms for image and segmentation
train_transforms = Compose(
[
LoadImaged(keys=["image", "label"]),
AsChannelFirstd(keys=["image", "label"], channel_dim=-1),
ScaleIntensityd(keys="image"),
RandCropByPosNegLabeld(
keys=["image", "label"], label_key="label", spatial_size=[96, 96, 96], pos=1, neg=1, num_samples=4
),
RandRotate90d(keys=["image", "label"], prob=0.5, spatial_axes=[0, 2]),
ToTensord(keys=["image", "label"]),
]
)
val_transforms = Compose(
[
LoadImaged(keys=["image", "label"]),
AsChannelFirstd(keys=["image", "label"], channel_dim=-1),
ScaleIntensityd(keys="image"),
ToTensord(keys=["image", "label"]),
]
)
# create a training data loader
train_ds = monai.data.CacheDataset(data=train_files, transform=train_transforms, cache_rate=0.5)
# use batch_size=2 to load images and use RandCropByPosNegLabeld to generate 2 x 4 images for network training
train_loader = monai.data.DataLoader(train_ds, batch_size=2, shuffle=True, num_workers=4)
# create a validation data loader
val_ds = monai.data.CacheDataset(data=val_files, transform=val_transforms, cache_rate=1.0)
val_loader = monai.data.DataLoader(val_ds, batch_size=1, num_workers=4)
################################ DATASET ################################
################################ NETWORK ################################
# create UNet, DiceLoss and Adam optimizer
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
net = monai.networks.nets.UNet(
dimensions=3,
in_channels=1,
out_channels=1,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
).to(device)
################################ NETWORK ################################
################################ LOSS ################################
loss = monai.losses.DiceLoss(sigmoid=True)
################################ LOSS ################################
################################ OPT ################################
opt = torch.optim.Adam(net.parameters(), 1e-3)
################################ OPT ################################
################################ LR ################################
lr_scheduler = torch.optim.lr_scheduler.StepLR(opt, step_size=2, gamma=0.1)
################################ LR ################################
val_post_transforms = Compose(
[
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold_values=True),
KeepLargestConnectedComponentd(keys="pred", applied_labels=[1]),
]
)
val_handlers = [
StatsHandler(output_transform=lambda x: None),
TensorBoardStatsHandler(log_dir="./runs/", output_transform=lambda x: None),
TensorBoardImageHandler(
log_dir="./runs/",
batch_transform=lambda x: (x["image"], x["label"]),
output_transform=lambda x: x["pred"],
),
CheckpointSaver(save_dir="./runs/", save_dict={"net": net}, save_key_metric=True),
]
evaluator = SupervisedEvaluator(
device=device,
val_data_loader=val_loader,
network=net,
inferer=SlidingWindowInferer(roi_size=(96, 96, 96), sw_batch_size=4, overlap=0.5),
post_transform=val_post_transforms,
key_val_metric={
"val_mean_dice": MeanDice(include_background=True, output_transform=lambda x: (x["pred"], x["label"]))
},
additional_metrics={"val_acc": Accuracy(output_transform=lambda x: (x["pred"], x["label"]))},
val_handlers=val_handlers,
# if no FP16 support in GPU or PyTorch version < 1.6, will not enable AMP evaluation
amp=True if monai.utils.get_torch_version_tuple() >= (1, 6) else False,
)
train_post_transforms = Compose(
[
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold_values=True),
KeepLargestConnectedComponentd(keys="pred", applied_labels=[1]),
]
)
train_handlers = [
LrScheduleHandler(lr_scheduler=lr_scheduler, print_lr=True),
ValidationHandler(validator=evaluator, interval=2, epoch_level=True),
StatsHandler(tag_name="train_loss", output_transform=lambda x: x["loss"]),
TensorBoardStatsHandler(log_dir="./runs/", tag_name="train_loss", output_transform=lambda x: x["loss"]),
CheckpointSaver(save_dir="./runs/", save_dict={"net": net, "opt": opt}, save_interval=2, epoch_level=True),
]
trainer = SupervisedTrainer(
device=device,
max_epochs=5,
train_data_loader=train_loader,
network=net,
optimizer=opt,
loss_function=loss,
inferer=SimpleInferer(),
post_transform=train_post_transforms,
key_train_metric={"train_acc": Accuracy(output_transform=lambda x: (x["pred"], x["label"]))},
train_handlers=train_handlers,
# if no FP16 support in GPU or PyTorch version < 1.6, will not enable AMP training
amp=True if monai.utils.get_torch_version_tuple() >= (1, 6) else False,
)
trainer.run()
def train(self,
train_info,
valid_info,
hyperparameters,
run_data_check=False):
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
if not run_data_check:
start_dt = datetime.datetime.now()
start_dt_string = start_dt.strftime('%d/%m/%Y %H:%M:%S')
print(f'Training started: {start_dt_string}')
# 1. Create folders to save the model
timedate_info = str(
datetime.datetime.now()).split(' ')[0] + '_' + str(
datetime.datetime.now().strftime("%H:%M:%S")).replace(
':', '-')
path_to_model = os.path.join(
self.out_dir, 'trained_models',
self.unique_name + '_' + timedate_info)
os.mkdir(path_to_model)
# 2. Load hyperparameters
learning_rate = hyperparameters['learning_rate']
weight_decay = hyperparameters['weight_decay']
total_epoch = hyperparameters['total_epoch']
multiplicator = hyperparameters['multiplicator']
batch_size = hyperparameters['batch_size']
validation_epoch = hyperparameters['validation_epoch']
validation_interval = hyperparameters['validation_interval']
H = hyperparameters['H']
L = hyperparameters['L']
# 3. Consider class imbalance
negative, positive = 0, 0
for _, label in train_info:
if int(label) == 0:
negative += 1
elif int(label) == 1:
positive += 1
pos_weight = torch.Tensor([(negative / positive)]).to(self.device)
# 4. Create train and validation loaders, batch_size = 10 for validation loader (10 central slices)
train_data = get_data_from_info(self.image_data_dir, self.seg_data_dir,
train_info)
valid_data = get_data_from_info(self.image_data_dir, self.seg_data_dir,
valid_info)
large_image_splitter(train_data, self.cache_dir)
set_determinism(seed=100)
train_trans, valid_trans = self.transformations(H, L)
train_dataset = PersistentDataset(
data=train_data[:],
transform=train_trans,
cache_dir=self.persistent_dataset_dir)
valid_dataset = PersistentDataset(
data=valid_data[:],
transform=valid_trans,
cache_dir=self.persistent_dataset_dir)
train_loader = DataLoader(train_dataset,
batch_size=batch_size,
shuffle=True,
pin_memory=self.pin_memory,
num_workers=self.num_workers,
collate_fn=PadListDataCollate(
Method.SYMMETRIC, NumpyPadMode.CONSTANT))
valid_loader = DataLoader(valid_dataset,
batch_size=batch_size,
shuffle=True,
pin_memory=self.pin_memory,
num_workers=self.num_workers,
collate_fn=PadListDataCollate(
Method.SYMMETRIC, NumpyPadMode.CONSTANT))
# Perform data checks
if run_data_check:
check_data = monai.utils.misc.first(train_loader)
print(check_data["image"].shape, check_data["label"])
for i in range(batch_size):
multi_slice_viewer(
check_data["image"][i, 0, :, :, :],
check_data["image_meta_dict"]["filename_or_obj"][i])
exit()
"""c = 1
for d in train_loader:
img = d["image"]
seg = d["seg"][0]
seg, _ = nrrd.read(seg)
img_name = d["image_meta_dict"]["filename_or_obj"][0]
print(c, "Name:", img_name, "Size:", img.nelement()*img.element_size()/1024/1024, "MB", "shape:", img.shape)
multi_slice_viewer(img[0, 0, :, :, :], d["image_meta_dict"]["filename_or_obj"][0])
#multi_slice_viewer(seg, d["image_meta_dict"]["filename_or_obj"][0])
c += 1
exit()"""
# 5. Prepare model
model = ModelCT().to(self.device)
# 6. Define loss function, optimizer and scheduler
loss_function = torch.nn.BCEWithLogitsLoss(
pos_weight) # pos_weight for class imbalance
optimizer = torch.optim.Adam(model.parameters(),
lr=learning_rate,
weight_decay=weight_decay)
scheduler = torch.optim.lr_scheduler.ExponentialLR(optimizer,
multiplicator,
last_epoch=-1)
# 7. Create post validation transforms and handlers
path_to_tensorboard = os.path.join(self.out_dir, 'tensorboard')
writer = SummaryWriter(log_dir=path_to_tensorboard)
valid_post_transforms = Compose([
Activationsd(keys="pred", sigmoid=True),
])
valid_handlers = [
StatsHandler(output_transform=lambda x: None),
TensorBoardStatsHandler(summary_writer=writer,
output_transform=lambda x: None),
CheckpointSaver(save_dir=path_to_model,
save_dict={"model": model},
save_key_metric=True),
MetricsSaver(save_dir=path_to_model,
metrics=['Valid_AUC', 'Valid_ACC']),
]
# 8. Create validatior
discrete = AsDiscrete(threshold_values=True)
evaluator = SupervisedEvaluator(
device=self.device,
val_data_loader=valid_loader,
network=model,
post_transform=valid_post_transforms,
key_val_metric={
"Valid_AUC":
ROCAUC(output_transform=lambda x: (x["pred"], x["label"]))
},
additional_metrics={
"Valid_Accuracy":
Accuracy(output_transform=lambda x:
(discrete(x["pred"]), x["label"]))
},
val_handlers=valid_handlers,
amp=self.amp,
)
# 9. Create trainer
# Loss function does the last sigmoid, so we dont need it here.
train_post_transforms = Compose([
# Empty
])
logger = MetricLogger(evaluator=evaluator)
train_handlers = [
logger,
LrScheduleHandler(lr_scheduler=scheduler, print_lr=True),
ValidationHandlerCT(validator=evaluator,
start=validation_epoch,
interval=validation_interval,
epoch_level=True),
StatsHandler(tag_name="loss",
output_transform=lambda x: x["loss"]),
TensorBoardStatsHandler(summary_writer=writer,
tag_name="Train_Loss",
output_transform=lambda x: x["loss"]),
CheckpointSaver(save_dir=path_to_model,
save_dict={
"model": model,
"opt": optimizer
},
save_interval=1,
n_saved=1),
]
trainer = SupervisedTrainer(
device=self.device,
max_epochs=total_epoch,
train_data_loader=train_loader,
network=model,
optimizer=optimizer,
loss_function=loss_function,
post_transform=train_post_transforms,
train_handlers=train_handlers,
amp=self.amp,
)
# 10. Run trainer
trainer.run()
# 11. Save results
np.save(path_to_model + '/AUCS.npy',
np.array(logger.metrics['Valid_AUC']))
np.save(path_to_model + '/ACCS.npy',
np.array(logger.metrics['Valid_ACC']))
np.save(path_to_model + '/LOSSES.npy', np.array(logger.loss))
np.save(path_to_model + '/PARAMETERS.npy', np.array(hyperparameters))
return path_to_model
def run_training_test(root_dir, device="cuda:0", amp=False):
images = sorted(glob(os.path.join(root_dir, "img*.nii.gz")))
segs = sorted(glob(os.path.join(root_dir, "seg*.nii.gz")))
train_files = [{
"image": img,
"label": seg
} for img, seg in zip(images[:20], segs[:20])]
val_files = [{
"image": img,
"label": seg
} for img, seg in zip(images[-20:], segs[-20:])]
# define transforms for image and segmentation
train_transforms = Compose([
LoadNiftid(keys=["image", "label"]),
AsChannelFirstd(keys=["image", "label"], channel_dim=-1),
ScaleIntensityd(keys=["image", "label"]),
RandCropByPosNegLabeld(keys=["image", "label"],
label_key="label",
spatial_size=[96, 96, 96],
pos=1,
neg=1,
num_samples=4),
RandRotate90d(keys=["image", "label"], prob=0.5, spatial_axes=[0, 2]),
ToTensord(keys=["image", "label"]),
])
val_transforms = Compose([
LoadNiftid(keys=["image", "label"]),
AsChannelFirstd(keys=["image", "label"], channel_dim=-1),
ScaleIntensityd(keys=["image", "label"]),
ToTensord(keys=["image", "label"]),
])
# create a training data loader
train_ds = monai.data.CacheDataset(data=train_files,
transform=train_transforms,
cache_rate=0.5)
# use batch_size=2 to load images and use RandCropByPosNegLabeld to generate 2 x 4 images for network training
train_loader = monai.data.DataLoader(train_ds,
batch_size=2,
shuffle=True,
num_workers=4)
# create a validation data loader
val_ds = monai.data.CacheDataset(data=val_files,
transform=val_transforms,
cache_rate=1.0)
val_loader = monai.data.DataLoader(val_ds, batch_size=1, num_workers=4)
# create UNet, DiceLoss and Adam optimizer
net = monai.networks.nets.UNet(
dimensions=3,
in_channels=1,
out_channels=1,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
).to(device)
loss = monai.losses.DiceLoss(sigmoid=True)
opt = torch.optim.Adam(net.parameters(), 1e-3)
lr_scheduler = torch.optim.lr_scheduler.StepLR(opt, step_size=2, gamma=0.1)
val_post_transforms = Compose([
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold_values=True),
KeepLargestConnectedComponentd(keys="pred", applied_labels=[1]),
])
val_handlers = [
StatsHandler(output_transform=lambda x: None),
TensorBoardStatsHandler(log_dir=root_dir,
output_transform=lambda x: None),
TensorBoardImageHandler(log_dir=root_dir,
batch_transform=lambda x:
(x["image"], x["label"]),
output_transform=lambda x: x["pred"]),
CheckpointSaver(save_dir=root_dir,
save_dict={"net": net},
save_key_metric=True),
]
evaluator = SupervisedEvaluator(
device=device,
val_data_loader=val_loader,
network=net,
inferer=SlidingWindowInferer(roi_size=(96, 96, 96),
sw_batch_size=4,
overlap=0.5),
post_transform=val_post_transforms,
key_val_metric={
"val_mean_dice":
MeanDice(include_background=True,
output_transform=lambda x: (x["pred"], x["label"]))
},
additional_metrics={
"val_acc":
Accuracy(output_transform=lambda x: (x["pred"], x["label"]))
},
val_handlers=val_handlers,
amp=True if amp else False,
)
train_post_transforms = Compose([
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold_values=True),
KeepLargestConnectedComponentd(keys="pred", applied_labels=[1]),
])
train_handlers = [
LrScheduleHandler(lr_scheduler=lr_scheduler, print_lr=True),
ValidationHandler(validator=evaluator, interval=2, epoch_level=True),
StatsHandler(tag_name="train_loss",
output_transform=lambda x: x["loss"]),
TensorBoardStatsHandler(log_dir=root_dir,
tag_name="train_loss",
output_transform=lambda x: x["loss"]),
CheckpointSaver(save_dir=root_dir,
save_dict={
"net": net,
"opt": opt
},
save_interval=2,
epoch_level=True),
]
trainer = SupervisedTrainer(
device=device,
max_epochs=5,
train_data_loader=train_loader,
network=net,
optimizer=opt,
loss_function=loss,
inferer=SimpleInferer(),
post_transform=train_post_transforms,
key_train_metric={
"train_acc":
Accuracy(output_transform=lambda x: (x["pred"], x["label"]))
},
train_handlers=train_handlers,
amp=True if amp else False,
)
trainer.run()
return evaluator.state.best_metric
def main():
monai.config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
# create a temporary directory and 40 random image, mask paris
tempdir = tempfile.mkdtemp()
print(f"generating synthetic data to {tempdir} (this may take a while)")
for i in range(40):
im, seg = create_test_image_3d(128,
128,
128,
num_seg_classes=1,
channel_dim=-1)
n = nib.Nifti1Image(im, np.eye(4))
nib.save(n, os.path.join(tempdir, f"img{i:d}.nii.gz"))
n = nib.Nifti1Image(seg, np.eye(4))
nib.save(n, os.path.join(tempdir, f"seg{i:d}.nii.gz"))
images = sorted(glob(os.path.join(tempdir, "img*.nii.gz")))
segs = sorted(glob(os.path.join(tempdir, "seg*.nii.gz")))
train_files = [{
"img": img,
"seg": seg
} for img, seg in zip(images[:20], segs[:20])]
val_files = [{
"img": img,
"seg": seg
} for img, seg in zip(images[-20:], segs[-20:])]
# define transforms for image and segmentation
train_transforms = Compose([
LoadNiftid(keys=["img", "seg"]),
AsChannelFirstd(keys=["img", "seg"], channel_dim=-1),
ScaleIntensityd(keys=["img", "seg"]),
RandCropByPosNegLabeld(keys=["img", "seg"],
label_key="seg",
spatial_size=[96, 96, 96],
pos=1,
neg=1,
num_samples=4),
RandRotate90d(keys=["img", "seg"], prob=0.5, spatial_axes=[0, 2]),
ToTensord(keys=["img", "seg"]),
])
val_transforms = Compose([
LoadNiftid(keys=["img", "seg"]),
AsChannelFirstd(keys=["img", "seg"], channel_dim=-1),
ScaleIntensityd(keys=["img", "seg"]),
ToTensord(keys=["img", "seg"]),
])
# define dataset, data loader
check_ds = monai.data.Dataset(data=train_files, transform=train_transforms)
# use batch_size=2 to load images and use RandCropByPosNegLabeld to generate 2 x 4 images for network training
check_loader = DataLoader(check_ds,
batch_size=2,
num_workers=4,
collate_fn=list_data_collate,
pin_memory=torch.cuda.is_available())
check_data = monai.utils.misc.first(check_loader)
print(check_data["img"].shape, check_data["seg"].shape)
# create a training data loader
train_ds = monai.data.Dataset(data=train_files, transform=train_transforms)
# use batch_size=2 to load images and use RandCropByPosNegLabeld to generate 2 x 4 images for network training
train_loader = DataLoader(
train_ds,
batch_size=2,
shuffle=True,
num_workers=4,
collate_fn=list_data_collate,
pin_memory=torch.cuda.is_available(),
)
# create a validation data loader
val_ds = monai.data.Dataset(data=val_files, transform=val_transforms)
val_loader = DataLoader(val_ds,
batch_size=5,
num_workers=8,
collate_fn=list_data_collate,
pin_memory=torch.cuda.is_available())
# create UNet, DiceLoss and Adam optimizer
net = monai.networks.nets.UNet(
dimensions=3,
in_channels=1,
out_channels=1,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
)
loss = monai.losses.DiceLoss(sigmoid=True)
lr = 1e-3
opt = torch.optim.Adam(net.parameters(), lr)
device = torch.device("cuda:0")
# Ignite trainer expects batch=(img, seg) and returns output=loss at every iteration,
# user can add output_transform to return other values, like: y_pred, y, etc.
def prepare_batch(batch, device=None, non_blocking=False):
return _prepare_batch((batch["img"], batch["seg"]), device,
non_blocking)
trainer = create_supervised_trainer(net,
opt,
loss,
device,
False,
prepare_batch=prepare_batch)
# adding checkpoint handler to save models (network params and optimizer stats) during training
checkpoint_handler = ModelCheckpoint("./runs/",
"net",
n_saved=10,
require_empty=False)
trainer.add_event_handler(event_name=Events.EPOCH_COMPLETED,
handler=checkpoint_handler,
to_save={
"net": net,
"opt": opt
})
# StatsHandler prints loss at every iteration and print metrics at every epoch,
# we don't set metrics for trainer here, so just print loss, user can also customize print functions
# and can use output_transform to convert engine.state.output if it's not loss value
train_stats_handler = StatsHandler(name="trainer")
train_stats_handler.attach(trainer)
# TensorBoardStatsHandler plots loss at every iteration and plots metrics at every epoch, same as StatsHandler
train_tensorboard_stats_handler = TensorBoardStatsHandler()
train_tensorboard_stats_handler.attach(trainer)
validation_every_n_iters = 5
# set parameters for validation
metric_name = "Mean_Dice"
# add evaluation metric to the evaluator engine
val_metrics = {metric_name: MeanDice(sigmoid=True, to_onehot_y=False)}
# Ignite evaluator expects batch=(img, seg) and returns output=(y_pred, y) at every iteration,
# user can add output_transform to return other values
evaluator = create_supervised_evaluator(net,
val_metrics,
device,
True,
prepare_batch=prepare_batch)
@trainer.on(Events.ITERATION_COMPLETED(every=validation_every_n_iters))
def run_validation(engine):
evaluator.run(val_loader)
# add early stopping handler to evaluator
early_stopper = EarlyStopping(
patience=4,
score_function=stopping_fn_from_metric(metric_name),
trainer=trainer)
evaluator.add_event_handler(event_name=Events.EPOCH_COMPLETED,
handler=early_stopper)
# add stats event handler to print validation stats via evaluator
val_stats_handler = StatsHandler(
name="evaluator",
output_transform=lambda x:
None, # no need to print loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.epoch,
) # fetch global epoch number from trainer
val_stats_handler.attach(evaluator)
# add handler to record metrics to TensorBoard at every validation epoch
val_tensorboard_stats_handler = TensorBoardStatsHandler(
output_transform=lambda x:
None, # no need to plot loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.iteration,
) # fetch global iteration number from trainer
val_tensorboard_stats_handler.attach(evaluator)
# add handler to draw the first image and the corresponding label and model output in the last batch
# here we draw the 3D output as GIF format along the depth axis, every 2 validation iterations.
val_tensorboard_image_handler = TensorBoardImageHandler(
batch_transform=lambda batch: (batch["img"], batch["seg"]),
output_transform=lambda output: predict_segmentation(output[0]),
global_iter_transform=lambda x: trainer.state.epoch,
)
evaluator.add_event_handler(event_name=Events.ITERATION_COMPLETED(every=2),
handler=val_tensorboard_image_handler)
train_epochs = 5
state = trainer.run(train_loader, train_epochs)
print(state)
shutil.rmtree(tempdir)
trainer = create_supervised_trainer(net, opt, loss, device, False)
# adding checkpoint handler to save models (network params and optimizer stats) during training
checkpoint_handler = ModelCheckpoint('./runs/', 'net', n_saved=10, require_empty=False)
trainer.add_event_handler(event_name=Events.EPOCH_COMPLETED,
handler=checkpoint_handler,
to_save={'net': net, 'opt': opt})
# StatsHandler prints loss at every iteration and print metrics at every epoch,
# we don't set metrics for trainer here, so just print loss, user can also customize print functions
# and can use output_transform to convert engine.state.output if it's not loss value
train_stats_handler = StatsHandler(name='trainer')
train_stats_handler.attach(trainer)
# TensorBoardStatsHandler plots loss at every iteration and plots metrics at every epoch, same as StatsHandler
train_tensorboard_stats_handler = TensorBoardStatsHandler()
train_tensorboard_stats_handler.attach(trainer)
# set parameters for validation
validation_every_n_epochs = 1
metric_name = 'Accuracy'
# add evaluation metric to the evaluator engine
val_metrics = {metric_name: Accuracy()}
# ignite evaluator expects batch=(img, label) and returns output=(y_pred, y) at every iteration,
# user can add output_transform to return other values
evaluator = create_supervised_evaluator(net, val_metrics, device, True)
# add stats event handler to print validation stats via evaluator
val_stats_handler = StatsHandler(
name='evaluator',
def train(cfg):
log_dir = create_log_dir(cfg)
device = set_device(cfg)
# --------------------------------------------------------------------------
# Data Loading and Preprocessing
# --------------------------------------------------------------------------
# __________________________________________________________________________
# Build MONAI preprocessing
train_preprocess = Compose([
ToTensorD(keys="image"),
TorchVisionD(keys="image",
name="ColorJitter",
brightness=64.0 / 255.0,
contrast=0.75,
saturation=0.25,
hue=0.04),
ToNumpyD(keys="image"),
RandFlipD(keys="image", prob=0.5),
RandRotate90D(keys="image", prob=0.5),
CastToTypeD(keys="image", dtype=np.float32),
RandZoomD(keys="image", prob=0.5, min_zoom=0.9, max_zoom=1.1),
ScaleIntensityRangeD(keys="image",
a_min=0.0,
a_max=255.0,
b_min=-1.0,
b_max=1.0),
ToTensorD(keys=("image", "label")),
])
valid_preprocess = Compose([
CastToTypeD(keys="image", dtype=np.float32),
ScaleIntensityRangeD(keys="image",
a_min=0.0,
a_max=255.0,
b_min=-1.0,
b_max=1.0),
ToTensorD(keys=("image", "label")),
])
# __________________________________________________________________________
# Create MONAI dataset
train_json_info_list = load_decathlon_datalist(
data_list_file_path=cfg["dataset_json"],
data_list_key="training",
base_dir=cfg["data_root"],
)
valid_json_info_list = load_decathlon_datalist(
data_list_file_path=cfg["dataset_json"],
data_list_key="validation",
base_dir=cfg["data_root"],
)
train_dataset = PatchWSIDataset(
train_json_info_list,
cfg["region_size"],
cfg["grid_shape"],
cfg["patch_size"],
train_preprocess,
image_reader_name="openslide" if cfg["use_openslide"] else "cuCIM",
)
valid_dataset = PatchWSIDataset(
valid_json_info_list,
cfg["region_size"],
cfg["grid_shape"],
cfg["patch_size"],
valid_preprocess,
image_reader_name="openslide" if cfg["use_openslide"] else "cuCIM",
)
# __________________________________________________________________________
# DataLoaders
train_dataloader = DataLoader(train_dataset,
num_workers=cfg["num_workers"],
batch_size=cfg["batch_size"],
pin_memory=True)
valid_dataloader = DataLoader(valid_dataset,
num_workers=cfg["num_workers"],
batch_size=cfg["batch_size"],
pin_memory=True)
# __________________________________________________________________________
# Get sample batch and some info
first_sample = first(train_dataloader)
if first_sample is None:
raise ValueError("Fist sample is None!")
print("image: ")
print(" shape", first_sample["image"].shape)
print(" type: ", type(first_sample["image"]))
print(" dtype: ", first_sample["image"].dtype)
print("labels: ")
print(" shape", first_sample["label"].shape)
print(" type: ", type(first_sample["label"]))
print(" dtype: ", first_sample["label"].dtype)
print(f"batch size: {cfg['batch_size']}")
print(f"train number of batches: {len(train_dataloader)}")
print(f"valid number of batches: {len(valid_dataloader)}")
# --------------------------------------------------------------------------
# Deep Learning Classification Model
# --------------------------------------------------------------------------
# __________________________________________________________________________
# initialize model
model = TorchVisionFCModel("resnet18",
num_classes=1,
use_conv=True,
pretrained=cfg["pretrain"])
model = model.to(device)
# loss function
loss_func = torch.nn.BCEWithLogitsLoss()
loss_func = loss_func.to(device)
# optimizer
if cfg["novograd"]:
optimizer = Novograd(model.parameters(), cfg["lr"])
else:
optimizer = SGD(model.parameters(), lr=cfg["lr"], momentum=0.9)
# AMP scaler
if cfg["amp"]:
cfg["amp"] = True if monai.utils.get_torch_version_tuple() >= (
1, 6) else False
else:
cfg["amp"] = False
scheduler = lr_scheduler.CosineAnnealingLR(optimizer,
T_max=cfg["n_epochs"])
# --------------------------------------------
# Ignite Trainer/Evaluator
# --------------------------------------------
# Evaluator
val_handlers = [
CheckpointSaver(save_dir=log_dir,
save_dict={"net": model},
save_key_metric=True),
StatsHandler(output_transform=lambda x: None),
TensorBoardStatsHandler(log_dir=log_dir,
output_transform=lambda x: None),
]
val_postprocessing = Compose([
ActivationsD(keys="pred", sigmoid=True),
AsDiscreteD(keys="pred", threshold=0.5)
])
evaluator = SupervisedEvaluator(
device=device,
val_data_loader=valid_dataloader,
network=model,
postprocessing=val_postprocessing,
key_val_metric={
"val_acc":
Accuracy(output_transform=from_engine(["pred", "label"]))
},
val_handlers=val_handlers,
amp=cfg["amp"],
)
# Trainer
train_handlers = [
LrScheduleHandler(lr_scheduler=scheduler, print_lr=True),
CheckpointSaver(save_dir=cfg["logdir"],
save_dict={
"net": model,
"opt": optimizer
},
save_interval=1,
epoch_level=True),
StatsHandler(tag_name="train_loss",
output_transform=from_engine(["loss"], first=True)),
ValidationHandler(validator=evaluator, interval=1, epoch_level=True),
TensorBoardStatsHandler(log_dir=cfg["logdir"],
tag_name="train_loss",
output_transform=from_engine(["loss"],
first=True)),
]
train_postprocessing = Compose([
ActivationsD(keys="pred", sigmoid=True),
AsDiscreteD(keys="pred", threshold=0.5)
])
trainer = SupervisedTrainer(
device=device,
max_epochs=cfg["n_epochs"],
train_data_loader=train_dataloader,
network=model,
optimizer=optimizer,
loss_function=loss_func,
postprocessing=train_postprocessing,
key_train_metric={
"train_acc":
Accuracy(output_transform=from_engine(["pred", "label"]))
},
train_handlers=train_handlers,
amp=cfg["amp"],
)
trainer.run()
def run_training_test(root_dir, device="cuda:0"):
real_images = sorted(glob(os.path.join(root_dir, "img*.nii.gz")))
train_files = [{"reals": img} for img in zip(real_images)]
# prepare real data
train_transforms = Compose([
LoadNiftid(keys=["reals"]),
AsChannelFirstd(keys=["reals"]),
ScaleIntensityd(keys=["reals"]),
RandFlipd(keys=["reals"], prob=0.5),
ToTensord(keys=["reals"]),
])
train_ds = monai.data.CacheDataset(data=train_files,
transform=train_transforms,
cache_rate=0.5)
train_loader = monai.data.DataLoader(train_ds,
batch_size=2,
shuffle=True,
num_workers=4)
learning_rate = 2e-4
betas = (0.5, 0.999)
real_label = 1
fake_label = 0
# create discriminator
disc_net = Discriminator(in_shape=(1, 64, 64),
channels=(8, 16, 32, 64, 1),
strides=(2, 2, 2, 2, 1),
num_res_units=1,
kernel_size=5).to(device)
disc_net.apply(normal_init)
disc_opt = torch.optim.Adam(disc_net.parameters(),
learning_rate,
betas=betas)
disc_loss_criterion = torch.nn.BCELoss()
def discriminator_loss(gen_images, real_images):
real = real_images.new_full((real_images.shape[0], 1), real_label)
gen = gen_images.new_full((gen_images.shape[0], 1), fake_label)
realloss = disc_loss_criterion(disc_net(real_images), real)
genloss = disc_loss_criterion(disc_net(gen_images.detach()), gen)
return torch.div(torch.add(realloss, genloss), 2)
# create generator
latent_size = 64
gen_net = Generator(latent_shape=latent_size,
start_shape=(latent_size, 8, 8),
channels=[32, 16, 8, 1],
strides=[2, 2, 2, 1])
gen_net.apply(normal_init)
gen_net.conv.add_module("activation", torch.nn.Sigmoid())
gen_net = gen_net.to(device)
gen_opt = torch.optim.Adam(gen_net.parameters(),
learning_rate,
betas=betas)
gen_loss_criterion = torch.nn.BCELoss()
def generator_loss(gen_images):
output = disc_net(gen_images)
cats = output.new_full(output.shape, real_label)
return gen_loss_criterion(output, cats)
key_train_metric = None
train_handlers = [
StatsHandler(
name="training_loss",
output_transform=lambda x: {
Keys.GLOSS: x[Keys.GLOSS],
Keys.DLOSS: x[Keys.DLOSS]
},
),
TensorBoardStatsHandler(
log_dir=root_dir,
tag_name="training_loss",
output_transform=lambda x: {
Keys.GLOSS: x[Keys.GLOSS],
Keys.DLOSS: x[Keys.DLOSS]
},
),
CheckpointSaver(save_dir=root_dir,
save_dict={
"g_net": gen_net,
"d_net": disc_net
},
save_interval=2,
epoch_level=True),
]
disc_train_steps = 2
num_epochs = 5
trainer = GanTrainer(
device,
num_epochs,
train_loader,
gen_net,
gen_opt,
generator_loss,
disc_net,
disc_opt,
discriminator_loss,
d_train_steps=disc_train_steps,
latent_shape=latent_size,
key_train_metric=key_train_metric,
train_handlers=train_handlers,
)
trainer.run()
return trainer.state
def main(tempdir):
monai.config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
# create a temporary directory and 40 random image, mask pairs
print(f"generating synthetic data to {tempdir} (this may take a while)")
for i in range(40):
im, seg = create_test_image_3d(128, 128, 128, num_seg_classes=1)
n = nib.Nifti1Image(im, np.eye(4))
nib.save(n, os.path.join(tempdir, f"im{i:d}.nii.gz"))
n = nib.Nifti1Image(seg, np.eye(4))
nib.save(n, os.path.join(tempdir, f"seg{i:d}.nii.gz"))
images = sorted(glob(os.path.join(tempdir, "im*.nii.gz")))
segs = sorted(glob(os.path.join(tempdir, "seg*.nii.gz")))
# define transforms for image and segmentation
train_imtrans = Compose([
ScaleIntensity(),
AddChannel(),
RandSpatialCrop((96, 96, 96), random_size=False),
EnsureType(),
])
train_segtrans = Compose([
AddChannel(),
RandSpatialCrop((96, 96, 96), random_size=False),
EnsureType()
])
val_imtrans = Compose(
[ScaleIntensity(),
AddChannel(),
Resize((96, 96, 96)),
EnsureType()])
val_segtrans = Compose([AddChannel(), Resize((96, 96, 96)), EnsureType()])
# define image dataset, data loader
check_ds = ImageDataset(images,
segs,
transform=train_imtrans,
seg_transform=train_segtrans)
check_loader = DataLoader(check_ds,
batch_size=10,
num_workers=2,
pin_memory=torch.cuda.is_available())
im, seg = monai.utils.misc.first(check_loader)
print(im.shape, seg.shape)
# create a training data loader
train_ds = ImageDataset(images[:20],
segs[:20],
transform=train_imtrans,
seg_transform=train_segtrans)
train_loader = DataLoader(
train_ds,
batch_size=5,
shuffle=True,
num_workers=8,
pin_memory=torch.cuda.is_available(),
)
# create a validation data loader
val_ds = ImageDataset(images[-20:],
segs[-20:],
transform=val_imtrans,
seg_transform=val_segtrans)
val_loader = DataLoader(val_ds,
batch_size=5,
num_workers=8,
pin_memory=torch.cuda.is_available())
# create UNet, DiceLoss and Adam optimizer
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
net = monai.networks.nets.UNet(
spatial_dims=3,
in_channels=1,
out_channels=1,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
).to(device)
loss = monai.losses.DiceLoss(sigmoid=True)
lr = 1e-3
opt = torch.optim.Adam(net.parameters(), lr)
# Ignite trainer expects batch=(img, seg) and returns output=loss at every iteration,
# user can add output_transform to return other values, like: y_pred, y, etc.
trainer = create_supervised_trainer(net, opt, loss, device, False)
# adding checkpoint handler to save models (network params and optimizer stats) during training
checkpoint_handler = ModelCheckpoint("./runs_array/",
"net",
n_saved=10,
require_empty=False)
trainer.add_event_handler(
event_name=Events.EPOCH_COMPLETED,
handler=checkpoint_handler,
to_save={
"net": net,
"opt": opt
},
)
# StatsHandler prints loss at every iteration and print metrics at every epoch,
# we don't set metrics for trainer here, so just print loss, user can also customize print functions
# and can use output_transform to convert engine.state.output if it's not a loss value
train_stats_handler = StatsHandler(name="trainer",
output_transform=lambda x: x)
train_stats_handler.attach(trainer)
# TensorBoardStatsHandler plots loss at every iteration and plots metrics at every epoch, same as StatsHandler
train_tensorboard_stats_handler = TensorBoardStatsHandler(
output_transform=lambda x: x)
train_tensorboard_stats_handler.attach(trainer)
validation_every_n_epochs = 1
# Set parameters for validation
metric_name = "Mean_Dice"
# add evaluation metric to the evaluator engine
val_metrics = {metric_name: MeanDice()}
post_pred = Compose(
[EnsureType(),
Activations(sigmoid=True),
AsDiscrete(threshold=0.5)])
post_label = Compose([EnsureType(), AsDiscrete(threshold=0.5)])
# Ignite evaluator expects batch=(img, seg) and returns output=(y_pred, y) at every iteration,
# user can add output_transform to return other values
evaluator = create_supervised_evaluator(
net,
val_metrics,
device,
True,
output_transform=lambda x, y, y_pred:
([post_pred(i) for i in decollate_batch(y_pred)],
[post_label(i) for i in decollate_batch(y)]),
)
@trainer.on(Events.EPOCH_COMPLETED(every=validation_every_n_epochs))
def run_validation(engine):
evaluator.run(val_loader)
# add early stopping handler to evaluator
early_stopper = EarlyStopping(
patience=4,
score_function=stopping_fn_from_metric(metric_name),
trainer=trainer)
evaluator.add_event_handler(event_name=Events.EPOCH_COMPLETED,
handler=early_stopper)
# add stats event handler to print validation stats via evaluator
val_stats_handler = StatsHandler(
name="evaluator",
output_transform=lambda x:
None, # no need to print loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.epoch,
) # fetch global epoch number from trainer
val_stats_handler.attach(evaluator)
# add handler to record metrics to TensorBoard at every validation epoch
val_tensorboard_stats_handler = TensorBoardStatsHandler(
output_transform=lambda x:
None, # no need to plot loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.epoch,
) # fetch global epoch number from trainer
val_tensorboard_stats_handler.attach(evaluator)
# add handler to draw the first image and the corresponding label and model output in the last batch
# here we draw the 3D output as GIF format along Depth axis, at every validation epoch
val_tensorboard_image_handler = TensorBoardImageHandler(
batch_transform=lambda batch: (batch[0], batch[1]),
output_transform=lambda output: output[0],
global_iter_transform=lambda x: trainer.state.epoch,
)
evaluator.add_event_handler(event_name=Events.EPOCH_COMPLETED,
handler=val_tensorboard_image_handler)
train_epochs = 30
state = trainer.run(train_loader, train_epochs)
print(state)
def main():
monai.config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
# IXI dataset as a demo, downloadable from https://brain-development.org/ixi-dataset/
# the path of ixi IXI-T1 dataset
data_path = os.sep.join([".", "workspace", "data", "medical", "ixi", "IXI-T1"])
images = [
"IXI314-IOP-0889-T1.nii.gz",
"IXI249-Guys-1072-T1.nii.gz",
"IXI609-HH-2600-T1.nii.gz",
"IXI173-HH-1590-T1.nii.gz",
"IXI020-Guys-0700-T1.nii.gz",
"IXI342-Guys-0909-T1.nii.gz",
"IXI134-Guys-0780-T1.nii.gz",
"IXI577-HH-2661-T1.nii.gz",
"IXI066-Guys-0731-T1.nii.gz",
"IXI130-HH-1528-T1.nii.gz",
"IXI607-Guys-1097-T1.nii.gz",
"IXI175-HH-1570-T1.nii.gz",
"IXI385-HH-2078-T1.nii.gz",
"IXI344-Guys-0905-T1.nii.gz",
"IXI409-Guys-0960-T1.nii.gz",
"IXI584-Guys-1129-T1.nii.gz",
"IXI253-HH-1694-T1.nii.gz",
"IXI092-HH-1436-T1.nii.gz",
"IXI574-IOP-1156-T1.nii.gz",
"IXI585-Guys-1130-T1.nii.gz",
]
images = [os.sep.join([data_path, f]) for f in images]
# 2 binary labels for gender classification: man and woman
labels = np.array([0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0], dtype=np.int64)
# define transforms
train_transforms = Compose([ScaleIntensity(), AddChannel(), Resize((96, 96, 96)), RandRotate90(), EnsureType()])
val_transforms = Compose([ScaleIntensity(), AddChannel(), Resize((96, 96, 96)), EnsureType()])
# define image dataset, data loader
check_ds = ImageDataset(image_files=images, labels=labels, transform=train_transforms)
check_loader = DataLoader(check_ds, batch_size=2, num_workers=2, pin_memory=torch.cuda.is_available())
im, label = monai.utils.misc.first(check_loader)
print(type(im), im.shape, label)
# create DenseNet121, CrossEntropyLoss and Adam optimizer
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
net = monai.networks.nets.DenseNet121(spatial_dims=3, in_channels=1, out_channels=2).to(device)
loss = torch.nn.CrossEntropyLoss()
lr = 1e-5
opt = torch.optim.Adam(net.parameters(), lr)
# Ignite trainer expects batch=(img, label) and returns output=loss at every iteration,
# user can add output_transform to return other values, like: y_pred, y, etc.
trainer = create_supervised_trainer(net, opt, loss, device, False)
# adding checkpoint handler to save models (network params and optimizer stats) during training
checkpoint_handler = ModelCheckpoint("./runs_array/", "net", n_saved=10, require_empty=False)
trainer.add_event_handler(
event_name=Events.EPOCH_COMPLETED, handler=checkpoint_handler, to_save={"net": net, "opt": opt}
)
# StatsHandler prints loss at every iteration and print metrics at every epoch,
# we don't set metrics for trainer here, so just print loss, user can also customize print functions
# and can use output_transform to convert engine.state.output if it's not loss value
train_stats_handler = StatsHandler(name="trainer", output_transform=lambda x: x)
train_stats_handler.attach(trainer)
# TensorBoardStatsHandler plots loss at every iteration and plots metrics at every epoch, same as StatsHandler
train_tensorboard_stats_handler = TensorBoardStatsHandler(output_transform=lambda x: x)
train_tensorboard_stats_handler.attach(trainer)
# set parameters for validation
validation_every_n_epochs = 1
metric_name = "Accuracy"
# add evaluation metric to the evaluator engine
val_metrics = {metric_name: Accuracy()}
# Ignite evaluator expects batch=(img, label) and returns output=(y_pred, y) at every iteration,
# user can add output_transform to return other values
evaluator = create_supervised_evaluator(net, val_metrics, device, True)
# add stats event handler to print validation stats via evaluator
val_stats_handler = StatsHandler(
name="evaluator",
output_transform=lambda x: None, # no need to print loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.epoch,
) # fetch global epoch number from trainer
val_stats_handler.attach(evaluator)
# add handler to record metrics to TensorBoard at every epoch
val_tensorboard_stats_handler = TensorBoardStatsHandler(
output_transform=lambda x: None, # no need to plot loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.epoch,
) # fetch global epoch number from trainer
val_tensorboard_stats_handler.attach(evaluator)
# add early stopping handler to evaluator
early_stopper = EarlyStopping(patience=4, score_function=stopping_fn_from_metric(metric_name), trainer=trainer)
evaluator.add_event_handler(event_name=Events.EPOCH_COMPLETED, handler=early_stopper)
# create a validation data loader
val_ds = ImageDataset(image_files=images[-10:], labels=labels[-10:], transform=val_transforms)
val_loader = DataLoader(val_ds, batch_size=2, num_workers=2, pin_memory=torch.cuda.is_available())
@trainer.on(Events.EPOCH_COMPLETED(every=validation_every_n_epochs))
def run_validation(engine):
evaluator.run(val_loader)
# create a training data loader
train_ds = ImageDataset(image_files=images[:10], labels=labels[:10], transform=train_transforms)
train_loader = DataLoader(train_ds, batch_size=2, shuffle=True, num_workers=2, pin_memory=torch.cuda.is_available())
train_epochs = 30
state = trainer.run(train_loader, train_epochs)
print(state)
def configure(self):
self.set_device()
network = UNet(
dimensions=3,
in_channels=1,
out_channels=2,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
norm=Norm.BATCH,
).to(self.device)
if self.multi_gpu:
network = DistributedDataParallel(
module=network,
device_ids=[self.device],
find_unused_parameters=False,
)
train_transforms = Compose([
LoadImaged(keys=("image", "label")),
EnsureChannelFirstd(keys=("image", "label")),
Spacingd(keys=("image", "label"),
pixdim=[1.0, 1.0, 1.0],
mode=["bilinear", "nearest"]),
ScaleIntensityRanged(
keys="image",
a_min=-57,
a_max=164,
b_min=0.0,
b_max=1.0,
clip=True,
),
CropForegroundd(keys=("image", "label"), source_key="image"),
RandCropByPosNegLabeld(
keys=("image", "label"),
label_key="label",
spatial_size=(96, 96, 96),
pos=1,
neg=1,
num_samples=4,
image_key="image",
image_threshold=0,
),
RandShiftIntensityd(keys="image", offsets=0.1, prob=0.5),
ToTensord(keys=("image", "label")),
])
train_datalist = load_decathlon_datalist(self.data_list_file_path,
True, "training")
if self.multi_gpu:
train_datalist = partition_dataset(
data=train_datalist,
shuffle=True,
num_partitions=dist.get_world_size(),
even_divisible=True,
)[dist.get_rank()]
train_ds = CacheDataset(
data=train_datalist,
transform=train_transforms,
cache_num=32,
cache_rate=1.0,
num_workers=4,
)
train_data_loader = DataLoader(
train_ds,
batch_size=2,
shuffle=True,
num_workers=4,
)
val_transforms = Compose([
LoadImaged(keys=("image", "label")),
EnsureChannelFirstd(keys=("image", "label")),
ScaleIntensityRanged(
keys="image",
a_min=-57,
a_max=164,
b_min=0.0,
b_max=1.0,
clip=True,
),
CropForegroundd(keys=("image", "label"), source_key="image"),
ToTensord(keys=("image", "label")),
])
val_datalist = load_decathlon_datalist(self.data_list_file_path, True,
"validation")
val_ds = CacheDataset(val_datalist, val_transforms, 9, 0.0, 4)
val_data_loader = DataLoader(
val_ds,
batch_size=1,
shuffle=False,
num_workers=4,
)
post_transform = Compose([
Activationsd(keys="pred", softmax=True),
AsDiscreted(
keys=["pred", "label"],
argmax=[True, False],
to_onehot=True,
n_classes=2,
),
])
# metric
key_val_metric = {
"val_mean_dice":
MeanDice(
include_background=False,
output_transform=lambda x: (x["pred"], x["label"]),
device=self.device,
)
}
val_handlers = [
StatsHandler(output_transform=lambda x: None),
CheckpointSaver(
save_dir=self.ckpt_dir,
save_dict={"model": network},
save_key_metric=True,
),
TensorBoardStatsHandler(log_dir=self.ckpt_dir,
output_transform=lambda x: None),
]
self.eval_engine = SupervisedEvaluator(
device=self.device,
val_data_loader=val_data_loader,
network=network,
inferer=SlidingWindowInferer(
roi_size=[160, 160, 160],
sw_batch_size=4,
overlap=0.5,
),
post_transform=post_transform,
key_val_metric=key_val_metric,
val_handlers=val_handlers,
amp=self.amp,
)
optimizer = torch.optim.Adam(network.parameters(), self.learning_rate)
loss_function = DiceLoss(to_onehot_y=True, softmax=True)
lr_scheduler = torch.optim.lr_scheduler.StepLR(optimizer,
step_size=5000,
gamma=0.1)
train_handlers = [
LrScheduleHandler(lr_scheduler=lr_scheduler, print_lr=True),
ValidationHandler(validator=self.eval_engine,
interval=self.val_interval,
epoch_level=True),
StatsHandler(tag_name="train_loss",
output_transform=lambda x: x["loss"]),
TensorBoardStatsHandler(
log_dir=self.ckpt_dir,
tag_name="train_loss",
output_transform=lambda x: x["loss"],
),
]
self.train_engine = SupervisedTrainer(
device=self.device,
max_epochs=self.max_epochs,
train_data_loader=train_data_loader,
network=network,
optimizer=optimizer,
loss_function=loss_function,
inferer=SimpleInferer(),
post_transform=post_transform,
key_train_metric=None,
train_handlers=train_handlers,
amp=self.amp,
)
if self.local_rank > 0:
self.train_engine.logger.setLevel(logging.WARNING)
self.eval_engine.logger.setLevel(logging.WARNING)
def create_trainer(args):
set_determinism(seed=args.seed)
multi_gpu = args.multi_gpu
local_rank = args.local_rank
if multi_gpu:
dist.init_process_group(backend="nccl", init_method="env://")
device = torch.device("cuda:{}".format(local_rank))
torch.cuda.set_device(device)
else:
device = torch.device("cuda" if args.use_gpu else "cpu")
pre_transforms = get_pre_transforms(args.roi_size, args.model_size,
args.dimensions)
click_transforms = get_click_transforms()
post_transform = get_post_transforms()
train_loader, val_loader = get_loaders(args, pre_transforms)
# define training components
network = get_network(args.network, args.channels,
args.dimensions).to(device)
if multi_gpu:
network = torch.nn.parallel.DistributedDataParallel(
network, device_ids=[local_rank], output_device=local_rank)
if args.resume:
logging.info('{}:: Loading Network...'.format(local_rank))
map_location = {"cuda:0": "cuda:{}".format(local_rank)}
network.load_state_dict(
torch.load(args.model_filepath, map_location=map_location))
# define event-handlers for engine
val_handlers = [
StatsHandler(output_transform=lambda x: None),
TensorBoardStatsHandler(log_dir=args.output,
output_transform=lambda x: None),
DeepgrowStatsHandler(log_dir=args.output,
tag_name='val_dice',
image_interval=args.image_interval),
CheckpointSaver(save_dir=args.output,
save_dict={"net": network},
save_key_metric=True,
save_final=True,
save_interval=args.save_interval,
final_filename='model.pt')
]
val_handlers = val_handlers if local_rank == 0 else None
evaluator = SupervisedEvaluator(
device=device,
val_data_loader=val_loader,
network=network,
iteration_update=Interaction(
transforms=click_transforms,
max_interactions=args.max_val_interactions,
key_probability='probability',
train=False),
inferer=SimpleInferer(),
post_transform=post_transform,
key_val_metric={
"val_dice":
MeanDice(include_background=False,
output_transform=lambda x: (x["pred"], x["label"]))
},
val_handlers=val_handlers)
loss_function = DiceLoss(sigmoid=True, squared_pred=True)
optimizer = torch.optim.Adam(network.parameters(), args.learning_rate)
lr_scheduler = torch.optim.lr_scheduler.StepLR(optimizer,
step_size=5000,
gamma=0.1)
train_handlers = [
LrScheduleHandler(lr_scheduler=lr_scheduler, print_lr=True),
ValidationHandler(validator=evaluator,
interval=args.val_freq,
epoch_level=True),
StatsHandler(tag_name="train_loss",
output_transform=lambda x: x["loss"]),
TensorBoardStatsHandler(log_dir=args.output,
tag_name="train_loss",
output_transform=lambda x: x["loss"]),
CheckpointSaver(save_dir=args.output,
save_dict={
"net": network,
"opt": optimizer,
"lr": lr_scheduler
},
save_interval=args.save_interval * 2,
save_final=True,
final_filename='checkpoint.pt'),
]
train_handlers = train_handlers if local_rank == 0 else train_handlers[:2]
trainer = SupervisedTrainer(
device=device,
max_epochs=args.epochs,
train_data_loader=train_loader,
network=network,
iteration_update=Interaction(
transforms=click_transforms,
max_interactions=args.max_train_interactions,
key_probability='probability',
train=True),
optimizer=optimizer,
loss_function=loss_function,
inferer=SimpleInferer(),
post_transform=post_transform,
amp=args.amp,
key_train_metric={
"train_dice":
MeanDice(include_background=False,
output_transform=lambda x: (x["pred"], x["label"]))
},
train_handlers=train_handlers,
)
return trainer
def run_training_test(root_dir, device="cuda:0", amp=False, num_workers=4):
images = sorted(glob(os.path.join(root_dir, "img*.nii.gz")))
segs = sorted(glob(os.path.join(root_dir, "seg*.nii.gz")))
train_files = [{"image": img, "label": seg} for img, seg in zip(images[:20], segs[:20])]
val_files = [{"image": img, "label": seg} for img, seg in zip(images[-20:], segs[-20:])]
# define transforms for image and segmentation
train_transforms = Compose(
[
LoadImaged(keys=["image", "label"]),
AsChannelFirstd(keys=["image", "label"], channel_dim=-1),
ScaleIntensityd(keys=["image", "label"]),
RandCropByPosNegLabeld(
keys=["image", "label"], label_key="label", spatial_size=[96, 96, 96], pos=1, neg=1, num_samples=4
),
RandRotate90d(keys=["image", "label"], prob=0.5, spatial_axes=[0, 2]),
ToTensord(keys=["image", "label"]),
]
)
val_transforms = Compose(
[
LoadImaged(keys=["image", "label"]),
AsChannelFirstd(keys=["image", "label"], channel_dim=-1),
ScaleIntensityd(keys=["image", "label"]),
ToTensord(keys=["image", "label"]),
]
)
# create a training data loader
train_ds = monai.data.CacheDataset(data=train_files, transform=train_transforms, cache_rate=0.5)
# use batch_size=2 to load images and use RandCropByPosNegLabeld to generate 2 x 4 images for network training
train_loader = monai.data.DataLoader(train_ds, batch_size=2, shuffle=True, num_workers=num_workers)
# create a validation data loader
val_ds = monai.data.CacheDataset(data=val_files, transform=val_transforms, cache_rate=1.0)
val_loader = monai.data.DataLoader(val_ds, batch_size=1, num_workers=num_workers)
# create UNet, DiceLoss and Adam optimizer
net = monai.networks.nets.UNet(
spatial_dims=3,
in_channels=1,
out_channels=1,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
).to(device)
loss = monai.losses.DiceLoss(sigmoid=True)
opt = torch.optim.Adam(net.parameters(), 1e-3)
lr_scheduler = torch.optim.lr_scheduler.StepLR(opt, step_size=2, gamma=0.1)
summary_writer = SummaryWriter(log_dir=root_dir)
val_postprocessing = Compose(
[
ToTensord(keys=["pred", "label"]),
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold=0.5),
KeepLargestConnectedComponentd(keys="pred", applied_labels=[1]),
]
)
class _TestEvalIterEvents:
def attach(self, engine):
engine.add_event_handler(IterationEvents.FORWARD_COMPLETED, self._forward_completed)
def _forward_completed(self, engine):
pass
val_handlers = [
StatsHandler(iteration_log=False),
TensorBoardStatsHandler(summary_writer=summary_writer, iteration_log=False),
TensorBoardImageHandler(
log_dir=root_dir, batch_transform=from_engine(["image", "label"]), output_transform=from_engine("pred")
),
CheckpointSaver(save_dir=root_dir, save_dict={"net": net}, save_key_metric=True),
_TestEvalIterEvents(),
]
evaluator = SupervisedEvaluator(
device=device,
val_data_loader=val_loader,
network=net,
inferer=SlidingWindowInferer(roi_size=(96, 96, 96), sw_batch_size=4, overlap=0.5),
postprocessing=val_postprocessing,
key_val_metric={
"val_mean_dice": MeanDice(include_background=True, output_transform=from_engine(["pred", "label"]))
},
additional_metrics={"val_acc": Accuracy(output_transform=from_engine(["pred", "label"]))},
metric_cmp_fn=lambda cur, prev: cur >= prev, # if greater or equal, treat as new best metric
val_handlers=val_handlers,
amp=bool(amp),
to_kwargs={"memory_format": torch.preserve_format},
amp_kwargs={"dtype": torch.float16 if bool(amp) else torch.float32},
)
train_postprocessing = Compose(
[
ToTensord(keys=["pred", "label"]),
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold=0.5),
KeepLargestConnectedComponentd(keys="pred", applied_labels=[1]),
]
)
class _TestTrainIterEvents:
def attach(self, engine):
engine.add_event_handler(IterationEvents.FORWARD_COMPLETED, self._forward_completed)
engine.add_event_handler(IterationEvents.LOSS_COMPLETED, self._loss_completed)
engine.add_event_handler(IterationEvents.BACKWARD_COMPLETED, self._backward_completed)
engine.add_event_handler(IterationEvents.MODEL_COMPLETED, self._model_completed)
def _forward_completed(self, engine):
pass
def _loss_completed(self, engine):
pass
def _backward_completed(self, engine):
pass
def _model_completed(self, engine):
pass
train_handlers = [
LrScheduleHandler(lr_scheduler=lr_scheduler, print_lr=True),
ValidationHandler(validator=evaluator, interval=2, epoch_level=True),
StatsHandler(tag_name="train_loss", output_transform=from_engine("loss", first=True)),
TensorBoardStatsHandler(
summary_writer=summary_writer, tag_name="train_loss", output_transform=from_engine("loss", first=True)
),
CheckpointSaver(save_dir=root_dir, save_dict={"net": net, "opt": opt}, save_interval=2, epoch_level=True),
_TestTrainIterEvents(),
]
trainer = SupervisedTrainer(
device=device,
max_epochs=5,
train_data_loader=train_loader,
network=net,
optimizer=opt,
loss_function=loss,
inferer=SimpleInferer(),
postprocessing=train_postprocessing,
key_train_metric={"train_acc": Accuracy(output_transform=from_engine(["pred", "label"]))},
train_handlers=train_handlers,
amp=bool(amp),
optim_set_to_none=True,
to_kwargs={"memory_format": torch.preserve_format},
amp_kwargs={"dtype": torch.float16 if bool(amp) else torch.float32},
)
trainer.run()
return evaluator.state.best_metric
def main(tempdir):
monai.config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
################################ DATASET ################################
# get dataset
train_ds = CacheDataset(data=train_files,
transform=train_transforms,
cache_rate=0.5)
train_loader = DataLoader(train_ds,
batch_size=2,
shuffle=True,
num_workers=4)
val_ds = CacheDataset(data=val_files,
transform=val_transforms,
cache_rate=1.0)
val_loader = DataLoader(val_ds, batch_size=1, num_workers=4)
################################ DATASET ################################
################################ NETWORK ################################
# create UNet, DiceLoss and Adam optimizer
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
net = monai.networks.nets.UNet(
dimensions=3,
in_channels=1,
out_channels=1,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
).to(device)
################################ NETWORK ################################
################################ LOSS ################################
loss = monai.losses.DiceLoss(sigmoid=True)
################################ LOSS ################################
################################ OPT ################################
opt = torch.optim.Adam(net.parameters(), 1e-3)
################################ OPT ################################
################################ LR ################################
lr_scheduler = torch.optim.lr_scheduler.StepLR(opt, step_size=2, gamma=0.1)
################################ LR ################################
################################ Evalutaion ################################
val_post_transforms = ...
val_handlers = ...
evaluator = ...
train_post_transforms = Compose([
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold_values=True),
KeepLargestConnectedComponentd(keys="pred", applied_labels=[1]),
])
train_handlers = [
LrScheduleHandler(lr_scheduler=lr_scheduler, print_lr=True),
ValidationHandler(validator=evaluator, interval=2, epoch_level=True),
StatsHandler(tag_name="train_loss",
output_transform=lambda x: x["loss"]),
TensorBoardStatsHandler(log_dir="./runs/",
tag_name="train_loss",
output_transform=lambda x: x["loss"]),
CheckpointSaver(save_dir="./runs/",
save_dict={
"net": net,
"opt": opt
},
save_interval=2,
epoch_level=True),
]
trainer = SupervisedTrainer(
device=device,
max_epochs=5,
train_data_loader=train_loader,
network=net,
optimizer=opt,
loss_function=loss,
inferer=SimpleInferer(),
post_transform=train_post_transforms,
key_train_metric={
"train_acc":
Accuracy(output_transform=lambda x: (x["pred"], x["label"]))
},
train_handlers=train_handlers,
# if no FP16 support in GPU or PyTorch version < 1.6, will not enable AMP training
amp=True if monai.utils.get_torch_version_tuple() >= (1, 6) else False,
)
trainer.run()
def main():
monai.config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
# IXI dataset as a demo, downloadable from https://brain-development.org/ixi-dataset/
images = [
"/workspace/data/medical/ixi/IXI-T1/IXI314-IOP-0889-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI249-Guys-1072-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI609-HH-2600-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI173-HH-1590-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI020-Guys-0700-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI342-Guys-0909-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI134-Guys-0780-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI577-HH-2661-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI066-Guys-0731-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI130-HH-1528-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI607-Guys-1097-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI175-HH-1570-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI385-HH-2078-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI344-Guys-0905-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI409-Guys-0960-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI584-Guys-1129-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI253-HH-1694-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI092-HH-1436-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI574-IOP-1156-T1.nii.gz",
"/workspace/data/medical/ixi/IXI-T1/IXI585-Guys-1130-T1.nii.gz",
]
# 2 binary labels for gender classification: man and woman
labels = np.array(
[0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0])
train_files = [{
"img": img,
"label": label
} for img, label in zip(images[:10], labels[:10])]
val_files = [{
"img": img,
"label": label
} for img, label in zip(images[-10:], labels[-10:])]
# define transforms for image
train_transforms = Compose([
LoadNiftid(keys=["img"]),
AddChanneld(keys=["img"]),
ScaleIntensityd(keys=["img"]),
Resized(keys=["img"], spatial_size=(96, 96, 96)),
RandRotate90d(keys=["img"], prob=0.8, spatial_axes=[0, 2]),
ToTensord(keys=["img"]),
])
val_transforms = Compose([
LoadNiftid(keys=["img"]),
AddChanneld(keys=["img"]),
ScaleIntensityd(keys=["img"]),
Resized(keys=["img"], spatial_size=(96, 96, 96)),
ToTensord(keys=["img"]),
])
# define dataset, data loader
check_ds = monai.data.Dataset(data=train_files, transform=train_transforms)
check_loader = DataLoader(check_ds,
batch_size=2,
num_workers=4,
pin_memory=torch.cuda.is_available())
check_data = monai.utils.misc.first(check_loader)
print(check_data["img"].shape, check_data["label"])
# create DenseNet121, CrossEntropyLoss and Adam optimizer
net = monai.networks.nets.densenet.densenet121(
spatial_dims=3,
in_channels=1,
out_channels=2,
)
loss = torch.nn.CrossEntropyLoss()
lr = 1e-5
opt = torch.optim.Adam(net.parameters(), lr)
device = torch.device("cuda:0")
# Ignite trainer expects batch=(img, label) and returns output=loss at every iteration,
# user can add output_transform to return other values, like: y_pred, y, etc.
def prepare_batch(batch, device=None, non_blocking=False):
return _prepare_batch((batch["img"], batch["label"]), device,
non_blocking)
trainer = create_supervised_trainer(net,
opt,
loss,
device,
False,
prepare_batch=prepare_batch)
# adding checkpoint handler to save models (network params and optimizer stats) during training
checkpoint_handler = ModelCheckpoint("./runs/",
"net",
n_saved=10,
require_empty=False)
trainer.add_event_handler(event_name=Events.EPOCH_COMPLETED,
handler=checkpoint_handler,
to_save={
"net": net,
"opt": opt
})
# StatsHandler prints loss at every iteration and print metrics at every epoch,
# we don't set metrics for trainer here, so just print loss, user can also customize print functions
# and can use output_transform to convert engine.state.output if it's not loss value
train_stats_handler = StatsHandler(name="trainer")
train_stats_handler.attach(trainer)
# TensorBoardStatsHandler plots loss at every iteration and plots metrics at every epoch, same as StatsHandler
train_tensorboard_stats_handler = TensorBoardStatsHandler()
train_tensorboard_stats_handler.attach(trainer)
# set parameters for validation
validation_every_n_epochs = 1
metric_name = "Accuracy"
# add evaluation metric to the evaluator engine
val_metrics = {
metric_name: Accuracy(),
"AUC": ROCAUC(to_onehot_y=True, add_softmax=True)
}
# Ignite evaluator expects batch=(img, label) and returns output=(y_pred, y) at every iteration,
# user can add output_transform to return other values
evaluator = create_supervised_evaluator(net,
val_metrics,
device,
True,
prepare_batch=prepare_batch)
# add stats event handler to print validation stats via evaluator
val_stats_handler = StatsHandler(
name="evaluator",
output_transform=lambda x:
None, # no need to print loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.epoch,
) # fetch global epoch number from trainer
val_stats_handler.attach(evaluator)
# add handler to record metrics to TensorBoard at every epoch
val_tensorboard_stats_handler = TensorBoardStatsHandler(
output_transform=lambda x:
None, # no need to plot loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.epoch,
) # fetch global epoch number from trainer
val_tensorboard_stats_handler.attach(evaluator)
# add early stopping handler to evaluator
early_stopper = EarlyStopping(
patience=4,
score_function=stopping_fn_from_metric(metric_name),
trainer=trainer)
evaluator.add_event_handler(event_name=Events.EPOCH_COMPLETED,
handler=early_stopper)
# create a validation data loader
val_ds = monai.data.Dataset(data=val_files, transform=val_transforms)
val_loader = DataLoader(val_ds,
batch_size=2,
num_workers=4,
pin_memory=torch.cuda.is_available())
@trainer.on(Events.EPOCH_COMPLETED(every=validation_every_n_epochs))
def run_validation(engine):
evaluator.run(val_loader)
# create a training data loader
train_ds = monai.data.Dataset(data=train_files, transform=train_transforms)
train_loader = DataLoader(train_ds,
batch_size=2,
shuffle=True,
num_workers=4,
pin_memory=torch.cuda.is_available())
train_epochs = 30
state = trainer.run(train_loader, train_epochs)
def main():
"""
Basic UNet as implemented in MONAI for Fetal Brain Segmentation, but using
ignite to manage training and validation loop and checkpointing
:return:
"""
"""
Read input and configuration parameters
"""
parser = argparse.ArgumentParser(
description='Run basic UNet with MONAI - Ignite version.')
parser.add_argument('--config',
dest='config',
metavar='config',
type=str,
help='config file')
args = parser.parse_args()
with open(args.config) as f:
config_info = yaml.load(f, Loader=yaml.FullLoader)
# print to log the parameter setups
print(yaml.dump(config_info))
# GPU params
cuda_device = config_info['device']['cuda_device']
num_workers = config_info['device']['num_workers']
# training and validation params
loss_type = config_info['training']['loss_type']
batch_size_train = config_info['training']['batch_size_train']
batch_size_valid = config_info['training']['batch_size_valid']
lr = float(config_info['training']['lr'])
lr_decay = config_info['training']['lr_decay']
if lr_decay is not None:
lr_decay = float(lr_decay)
nr_train_epochs = config_info['training']['nr_train_epochs']
validation_every_n_epochs = config_info['training'][
'validation_every_n_epochs']
sliding_window_validation = config_info['training'][
'sliding_window_validation']
if 'model_to_load' in config_info['training'].keys():
model_to_load = config_info['training']['model_to_load']
if not os.path.exists(model_to_load):
raise BlockingIOError(
"cannot find model: {}".format(model_to_load))
else:
model_to_load = None
if 'manual_seed' in config_info['training'].keys():
seed = config_info['training']['manual_seed']
else:
seed = None
# data params
data_root = config_info['data']['data_root']
training_list = config_info['data']['training_list']
validation_list = config_info['data']['validation_list']
# model saving
out_model_dir = os.path.join(
config_info['output']['out_model_dir'],
datetime.now().strftime('%Y-%m-%d_%H-%M-%S') + '_' +
config_info['output']['output_subfix'])
print("Saving to directory ", out_model_dir)
if 'cache_dir' in config_info['output'].keys():
out_cache_dir = config_info['output']['cache_dir']
else:
out_cache_dir = os.path.join(out_model_dir, 'persistent_cache')
max_nr_models_saved = config_info['output']['max_nr_models_saved']
val_image_to_tensorboad = config_info['output']['val_image_to_tensorboad']
monai.config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
torch.cuda.set_device(cuda_device)
if seed is not None:
# set manual seed if required (both numpy and torch)
set_determinism(seed=seed)
# # set torch only seed
# torch.manual_seed(seed)
# torch.backends.cudnn.deterministic = True
# torch.backends.cudnn.benchmark = False
"""
Data Preparation
"""
# create cache directory to store results for Persistent Dataset
persistent_cache: Path = Path(out_cache_dir)
persistent_cache.mkdir(parents=True, exist_ok=True)
# create training and validation data lists
train_files = create_data_list(data_folder_list=data_root,
subject_list=training_list,
img_postfix='_Image',
label_postfix='_Label')
print(len(train_files))
print(train_files[0])
print(train_files[-1])
val_files = create_data_list(data_folder_list=data_root,
subject_list=validation_list,
img_postfix='_Image',
label_postfix='_Label')
print(len(val_files))
print(val_files[0])
print(val_files[-1])
# data preprocessing for training:
# - convert data to right format [batch, channel, dim, dim, dim]
# - apply whitening
# - resize to (96, 96) in-plane (preserve z-direction)
# - define 2D patches to be extracted
# - add data augmentation (random rotation and random flip)
# - squeeze to 2D
train_transforms = Compose([
LoadNiftid(keys=['img', 'seg']),
AddChanneld(keys=['img', 'seg']),
NormalizeIntensityd(keys=['img']),
Resized(keys=['img', 'seg'],
spatial_size=[96, 96],
interp_order=[1, 0],
anti_aliasing=[True, False]),
RandSpatialCropd(keys=['img', 'seg'],
roi_size=[96, 96, 1],
random_size=False),
RandRotated(keys=['img', 'seg'],
degrees=90,
prob=0.2,
spatial_axes=[0, 1],
interp_order=[1, 0],
reshape=False),
RandFlipd(keys=['img', 'seg'], spatial_axis=[0, 1]),
SqueezeDimd(keys=['img', 'seg'], dim=-1),
ToTensord(keys=['img', 'seg'])
])
# create a training data loader
# train_ds = monai.data.Dataset(data=train_files, transform=train_transforms)
# train_ds = monai.data.CacheDataset(data=train_files, transform=train_transforms, cache_rate=1.0,
# num_workers=num_workers)
train_ds = monai.data.PersistentDataset(data=train_files,
transform=train_transforms,
cache_dir=persistent_cache)
train_loader = DataLoader(train_ds,
batch_size=batch_size_train,
shuffle=True,
num_workers=num_workers,
collate_fn=list_data_collate,
pin_memory=torch.cuda.is_available())
# check_train_data = monai.utils.misc.first(train_loader)
# print("Training data tensor shapes")
# print(check_train_data['img'].shape, check_train_data['seg'].shape)
# data preprocessing for validation:
# - convert data to right format [batch, channel, dim, dim, dim]
# - apply whitening
# - resize to (96, 96) in-plane (preserve z-direction)
if sliding_window_validation:
val_transforms = Compose([
LoadNiftid(keys=['img', 'seg']),
AddChanneld(keys=['img', 'seg']),
NormalizeIntensityd(keys=['img']),
Resized(keys=['img', 'seg'],
spatial_size=[96, 96],
interp_order=[1, 0],
anti_aliasing=[True, False]),
ToTensord(keys=['img', 'seg'])
])
do_shuffle = False
collate_fn_to_use = None
else:
# - add extraction of 2D slices from validation set to emulate how loss is computed at training
val_transforms = Compose([
LoadNiftid(keys=['img', 'seg']),
AddChanneld(keys=['img', 'seg']),
NormalizeIntensityd(keys=['img']),
Resized(keys=['img', 'seg'],
spatial_size=[96, 96],
interp_order=[1, 0],
anti_aliasing=[True, False]),
RandSpatialCropd(keys=['img', 'seg'],
roi_size=[96, 96, 1],
random_size=False),
SqueezeDimd(keys=['img', 'seg'], dim=-1),
ToTensord(keys=['img', 'seg'])
])
do_shuffle = True
collate_fn_to_use = list_data_collate
# create a validation data loader
# val_ds = monai.data.Dataset(data=val_files, transform=val_transforms)
# val_ds = monai.data.CacheDataset(data=val_files, transform=val_transforms, cache_rate=1.0,
# num_workers=num_workers)
val_ds = monai.data.PersistentDataset(data=val_files,
transform=val_transforms,
cache_dir=persistent_cache)
val_loader = DataLoader(val_ds,
batch_size=batch_size_valid,
shuffle=do_shuffle,
collate_fn=collate_fn_to_use,
num_workers=num_workers)
# check_valid_data = monai.utils.misc.first(val_loader)
# print("Validation data tensor shapes")
# print(check_valid_data['img'].shape, check_valid_data['seg'].shape)
"""
Network preparation
"""
# Create UNet, DiceLoss and Adam optimizer.
net = monai.networks.nets.UNet(
dimensions=2,
in_channels=1,
out_channels=1,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
)
loss_function = monai.losses.DiceLoss(do_sigmoid=True)
opt = torch.optim.Adam(net.parameters(), lr)
device = torch.cuda.current_device()
if lr_decay is not None:
lr_scheduler = torch.optim.lr_scheduler.ExponentialLR(optimizer=opt,
gamma=lr_decay,
last_epoch=-1)
"""
Set ignite trainer
"""
# function to manage batch at training
def prepare_batch(batch, device=None, non_blocking=False):
return _prepare_batch((batch['img'], batch['seg']), device,
non_blocking)
trainer = create_supervised_trainer(model=net,
optimizer=opt,
loss_fn=loss_function,
device=device,
non_blocking=False,
prepare_batch=prepare_batch)
# adding checkpoint handler to save models (network params and optimizer stats) during training
if model_to_load is not None:
checkpoint_handler = CheckpointLoader(load_path=model_to_load,
load_dict={
'net': net,
'opt': opt,
})
checkpoint_handler.attach(trainer)
state = trainer.state_dict()
else:
checkpoint_handler = ModelCheckpoint(out_model_dir,
'net',
n_saved=max_nr_models_saved,
require_empty=False)
# trainer.add_event_handler(event_name=Events.EPOCH_COMPLETED, handler=save_params)
trainer.add_event_handler(event_name=Events.EPOCH_COMPLETED,
handler=checkpoint_handler,
to_save={
'net': net,
'opt': opt
})
# StatsHandler prints loss at every iteration and print metrics at every epoch
train_stats_handler = StatsHandler(name='trainer')
train_stats_handler.attach(trainer)
# TensorBoardStatsHandler plots loss at every iteration and plots metrics at every epoch, same as StatsHandler
writer_train = SummaryWriter(log_dir=os.path.join(out_model_dir, "train"))
train_tensorboard_stats_handler = TensorBoardStatsHandler(
summary_writer=writer_train)
train_tensorboard_stats_handler.attach(trainer)
if lr_decay is not None:
print("Using Exponential LR decay")
lr_schedule_handler = LrScheduleHandler(lr_scheduler,
print_lr=True,
name="lr_scheduler",
writer=writer_train)
lr_schedule_handler.attach(trainer)
"""
Set ignite evaluator to perform validation at training
"""
# set parameters for validation
metric_name = 'Mean_Dice'
# add evaluation metric to the evaluator engine
val_metrics = {
"Loss": 1.0 - MeanDice(add_sigmoid=True, to_onehot_y=False),
"Mean_Dice": MeanDice(add_sigmoid=True, to_onehot_y=False)
}
def _sliding_window_processor(engine, batch):
net.eval()
with torch.no_grad():
val_images, val_labels = batch['img'].to(device), batch['seg'].to(
device)
roi_size = (96, 96, 1)
seg_probs = sliding_window_inference(val_images, roi_size,
batch_size_valid, net)
return seg_probs, val_labels
if sliding_window_validation:
# use sliding window inference at validation
print("3D evaluator is used")
net.to(device)
evaluator = Engine(_sliding_window_processor)
for name, metric in val_metrics.items():
metric.attach(evaluator, name)
else:
# ignite evaluator expects batch=(img, seg) and returns output=(y_pred, y) at every iteration,
# user can add output_transform to return other values
print("2D evaluator is used")
evaluator = create_supervised_evaluator(model=net,
metrics=val_metrics,
device=device,
non_blocking=True,
prepare_batch=prepare_batch)
epoch_len = len(train_ds) // train_loader.batch_size
validation_every_n_iters = validation_every_n_epochs * epoch_len
@trainer.on(Events.ITERATION_COMPLETED(every=validation_every_n_iters))
def run_validation(engine):
evaluator.run(val_loader)
# add early stopping handler to evaluator
# early_stopper = EarlyStopping(patience=4,
# score_function=stopping_fn_from_metric(metric_name),
# trainer=trainer)
# evaluator.add_event_handler(event_name=Events.EPOCH_COMPLETED, handler=early_stopper)
# add stats event handler to print validation stats via evaluator
val_stats_handler = StatsHandler(
name='evaluator',
output_transform=lambda x:
None, # no need to print loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.epoch
) # fetch global epoch number from trainer
val_stats_handler.attach(evaluator)
# add handler to record metrics to TensorBoard at every validation epoch
writer_valid = SummaryWriter(log_dir=os.path.join(out_model_dir, "valid"))
val_tensorboard_stats_handler = TensorBoardStatsHandler(
summary_writer=writer_valid,
output_transform=lambda x:
None, # no need to plot loss value, so disable per iteration output
global_epoch_transform=lambda x: trainer.state.iteration
) # fetch global iteration number from trainer
val_tensorboard_stats_handler.attach(evaluator)
# add handler to draw the first image and the corresponding label and model output in the last batch
# here we draw the 3D output as GIF format along the depth axis, every 2 validation iterations.
if val_image_to_tensorboad:
val_tensorboard_image_handler = TensorBoardImageHandler(
summary_writer=writer_valid,
batch_transform=lambda batch: (batch['img'], batch['seg']),
output_transform=lambda output: predict_segmentation(output[0]),
global_iter_transform=lambda x: trainer.state.epoch)
evaluator.add_event_handler(
event_name=Events.ITERATION_COMPLETED(every=1),
handler=val_tensorboard_image_handler)
"""
Run training
"""
state = trainer.run(train_loader, nr_train_epochs)
print("Done!")
def run_training(train_file_list, valid_file_list, config_info):
"""
Pipeline to train a dynUNet segmentation model in MONAI. It is composed of the following main blocks:
* Data Preparation: Extract the filenames and prepare the training/validation processing transforms
* Load Data: Load training and validation data to PyTorch DataLoader
* Network Preparation: Define the network, loss function, optimiser and learning rate scheduler
* MONAI Evaluator: Initialise the dynUNet evaluator, i.e. the class providing utilities to perform validation
during training. Attach handlers to save the best model on the validation set. A 2D sliding window approach
on the 3D volume is used at evaluation. The mean 3D Dice is used as validation metric.
* MONAI Trainer: Initialise the dynUNet trainer, i.e. the class providing utilities to perform the training loop.
* Run training: The MONAI trainer is run, performing training and validation during training.
Args:
train_file_list: .txt or .csv file (with no header) storing two-columns filenames for training:
image filename in the first column and segmentation filename in the second column.
The two columns should be separated by a comma.
See monaifbs/config/mock_train_file_list_for_dynUnet_training.txt for an example of the expected format.
valid_file_list: .txt or .csv file (with no header) storing two-columns filenames for validation:
image filename in the first column and segmentation filename in the second column.
The two columns should be separated by a comma.
See monaifbs/config/mock_valid_file_list_for_dynUnet_training.txt for an example of the expected format.
config_info: dict, contains configuration parameters for sampling, network and training.
See monaifbs/config/monai_dynUnet_training_config.yml for an example of the expected fields.
"""
"""
Read input and configuration parameters
"""
# print MONAI config information
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
print_config()
# print to log the parameter setups
print(yaml.dump(config_info))
# extract network parameters, perform checks/set defaults if not present and print them to log
if 'seg_labels' in config_info['training'].keys():
seg_labels = config_info['training']['seg_labels']
else:
seg_labels = [1]
nr_out_channels = len(seg_labels)
print("Considering the following {} labels in the segmentation: {}".format(nr_out_channels, seg_labels))
patch_size = config_info["training"]["inplane_size"] + [1]
print("Considering patch size = {}".format(patch_size))
spacing = config_info["training"]["spacing"]
print("Bringing all images to spacing = {}".format(spacing))
if 'model_to_load' in config_info['training'].keys() and config_info['training']['model_to_load'] is not None:
model_to_load = config_info['training']['model_to_load']
if not os.path.exists(model_to_load):
raise FileNotFoundError("Cannot find model: {}".format(model_to_load))
else:
print("Loading model from {}".format(model_to_load))
else:
model_to_load = None
# set up either GPU or CPU usage
if torch.cuda.is_available():
print("\n#### GPU INFORMATION ###")
print("Using device number: {}, name: {}\n".format(torch.cuda.current_device(), torch.cuda.get_device_name()))
current_device = torch.device("cuda:0")
else:
current_device = torch.device("cpu")
print("Using device: {}".format(current_device))
# set determinism if required
if 'manual_seed' in config_info['training'].keys() and config_info['training']['manual_seed'] is not None:
seed = config_info['training']['manual_seed']
else:
seed = None
if seed is not None:
print("Using determinism with seed = {}\n".format(seed))
set_determinism(seed=seed)
"""
Setup data output directory
"""
out_model_dir = os.path.join(config_info['output']['out_dir'],
datetime.now().strftime('%Y-%m-%d_%H-%M-%S') + '_' +
config_info['output']['out_postfix'])
print("Saving to directory {}\n".format(out_model_dir))
# create cache directory to store results for Persistent Dataset
if 'cache_dir' in config_info['output'].keys():
out_cache_dir = config_info['output']['cache_dir']
else:
out_cache_dir = os.path.join(out_model_dir, 'persistent_cache')
persistent_cache: Path = Path(out_cache_dir)
persistent_cache.mkdir(parents=True, exist_ok=True)
"""
Data preparation
"""
# Read the input files for training and validation
print("*** Loading input data for training...")
train_files = create_data_list_of_dictionaries(train_file_list)
print("Number of inputs for training = {}".format(len(train_files)))
val_files = create_data_list_of_dictionaries(valid_file_list)
print("Number of inputs for validation = {}".format(len(val_files)))
# Define MONAI processing transforms for the training data. This includes:
# - Load Nifti files and convert to format Batch x Channel x Dim1 x Dim2 x Dim3
# - CropForegroundd: Reduce the background from the MR image
# - InPlaneSpacingd: Perform in-plane resampling to the desired spacing, but preserve the resolution along the
# last direction (lowest resolution) to avoid introducing motion artefact resampling errors
# - SpatialPadd: Pad the in-plane size to the defined network input patch size [N, M] if needed
# - NormalizeIntensityd: Apply whitening
# - RandSpatialCropd: Crop a random patch from the input with size [B, C, N, M, 1]
# - SqueezeDimd: Convert the 3D patch to a 2D one as input to the network (i.e. bring it to size [B, C, N, M])
# - Apply data augmentation (RandZoomd, RandRotated, RandGaussianNoised, RandGaussianSmoothd, RandScaleIntensityd,
# RandFlipd)
# - ToTensor: convert to pytorch tensor
train_transforms = Compose(
[
LoadNiftid(keys=["image", "label"]),
AddChanneld(keys=["image", "label"]),
CropForegroundd(keys=["image", "label"], source_key="image"),
InPlaneSpacingd(
keys=["image", "label"],
pixdim=spacing,
mode=("bilinear", "nearest"),
),
SpatialPadd(keys=["image", "label"], spatial_size=patch_size,
mode=["constant", "edge"]),
NormalizeIntensityd(keys=["image"], nonzero=False, channel_wise=True),
RandSpatialCropd(keys=["image", "label"], roi_size=patch_size, random_size=False),
SqueezeDimd(keys=["image", "label"], dim=-1),
RandZoomd(
keys=["image", "label"],
min_zoom=0.9,
max_zoom=1.2,
mode=("bilinear", "nearest"),
align_corners=(True, None),
prob=0.16,
),
RandRotated(keys=["image", "label"], range_x=90, range_y=90, prob=0.2,
keep_size=True, mode=["bilinear", "nearest"],
padding_mode=["zeros", "border"]),
RandGaussianNoised(keys=["image"], std=0.01, prob=0.15),
RandGaussianSmoothd(
keys=["image"],
sigma_x=(0.5, 1.15),
sigma_y=(0.5, 1.15),
sigma_z=(0.5, 1.15),
prob=0.15,
),
RandScaleIntensityd(keys=["image"], factors=0.3, prob=0.15),
RandFlipd(["image", "label"], spatial_axis=[0, 1], prob=0.5),
ToTensord(keys=["image", "label"]),
]
)
# Define MONAI processing transforms for the validation data
# - Load Nifti files and convert to format Batch x Channel x Dim1 x Dim2 x Dim3
# - CropForegroundd: Reduce the background from the MR image
# - InPlaneSpacingd: Perform in-plane resampling to the desired spacing, but preserve the resolution along the
# last direction (lowest resolution) to avoid introducing motion artefact resampling errors
# - SpatialPadd: Pad the in-plane size to the defined network input patch size [N, M] if needed
# - NormalizeIntensityd: Apply whitening
# - ToTensor: convert to pytorch tensor
# NOTE: The validation data is kept 3D as a 2D sliding window approach is used throughout the volume at inference
val_transforms = Compose(
[
LoadNiftid(keys=["image", "label"]),
AddChanneld(keys=["image", "label"]),
CropForegroundd(keys=["image", "label"], source_key="image"),
InPlaneSpacingd(
keys=["image", "label"],
pixdim=spacing,
mode=("bilinear", "nearest"),
),
SpatialPadd(keys=["image", "label"], spatial_size=patch_size, mode=["constant", "edge"]),
NormalizeIntensityd(keys=["image"], nonzero=False, channel_wise=True),
ToTensord(keys=["image", "label"]),
]
)
"""
Load data
"""
# create training data loader
train_ds = PersistentDataset(data=train_files, transform=train_transforms,
cache_dir=persistent_cache)
train_loader = DataLoader(train_ds,
batch_size=config_info['training']['batch_size_train'],
shuffle=True,
num_workers=config_info['device']['num_workers'])
check_train_data = misc.first(train_loader)
print("Training data tensor shapes:")
print("Image = {}; Label = {}".format(check_train_data["image"].shape, check_train_data["label"].shape))
# create validation data loader
if config_info['training']['batch_size_valid'] != 1:
raise Exception("Batch size different from 1 at validation ar currently not supported")
val_ds = PersistentDataset(data=val_files, transform=val_transforms, cache_dir=persistent_cache)
val_loader = DataLoader(val_ds,
batch_size=1,
shuffle=False,
num_workers=config_info['device']['num_workers'])
check_valid_data = misc.first(val_loader)
print("Validation data tensor shapes (Example):")
print("Image = {}; Label = {}\n".format(check_valid_data["image"].shape, check_valid_data["label"].shape))
"""
Network preparation
"""
print("*** Preparing the network ...")
# automatically extracts the strides and kernels based on nnU-Net empirical rules
spacings = spacing[:2]
sizes = patch_size[:2]
strides, kernels = [], []
while True:
spacing_ratio = [sp / min(spacings) for sp in spacings]
stride = [2 if ratio <= 2 and size >= 8 else 1 for (ratio, size) in zip(spacing_ratio, sizes)]
kernel = [3 if ratio <= 2 else 1 for ratio in spacing_ratio]
if all(s == 1 for s in stride):
break
sizes = [i / j for i, j in zip(sizes, stride)]
spacings = [i * j for i, j in zip(spacings, stride)]
kernels.append(kernel)
strides.append(stride)
strides.insert(0, len(spacings) * [1])
kernels.append(len(spacings) * [3])
# initialise the network
net = DynUNet(
spatial_dims=2,
in_channels=1,
out_channels=nr_out_channels,
kernel_size=kernels,
strides=strides,
upsample_kernel_size=strides[1:],
norm_name="instance",
deep_supervision=True,
deep_supr_num=2,
res_block=False,
).to(current_device)
print(net)
# define the loss function
loss_function = choose_loss_function(nr_out_channels, config_info)
# define the optimiser and the learning rate scheduler
opt = torch.optim.SGD(net.parameters(), lr=float(config_info['training']['lr']), momentum=0.95)
scheduler = torch.optim.lr_scheduler.LambdaLR(
opt, lr_lambda=lambda epoch: (1 - epoch / config_info['training']['nr_train_epochs']) ** 0.9
)
"""
MONAI evaluator
"""
print("*** Preparing the dynUNet evaluator engine...\n")
# val_post_transforms = Compose(
# [
# Activationsd(keys="pred", sigmoid=True),
# ]
# )
val_handlers = [
StatsHandler(output_transform=lambda x: None),
TensorBoardStatsHandler(log_dir=os.path.join(out_model_dir, "valid"),
output_transform=lambda x: None,
global_epoch_transform=lambda x: trainer.state.iteration),
CheckpointSaver(save_dir=out_model_dir, save_dict={"net": net, "opt": opt}, save_key_metric=True,
file_prefix='best_valid'),
]
if config_info['output']['val_image_to_tensorboad']:
val_handlers.append(TensorBoardImageHandler(log_dir=os.path.join(out_model_dir, "valid"),
batch_transform=lambda x: (x["image"], x["label"]),
output_transform=lambda x: x["pred"], interval=2))
# Define customized evaluator
class DynUNetEvaluator(SupervisedEvaluator):
def _iteration(self, engine, batchdata):
inputs, targets = self.prepare_batch(batchdata)
inputs, targets = inputs.to(engine.state.device), targets.to(engine.state.device)
flip_inputs_1 = torch.flip(inputs, dims=(2,))
flip_inputs_2 = torch.flip(inputs, dims=(3,))
flip_inputs_3 = torch.flip(inputs, dims=(2, 3))
def _compute_pred():
pred = self.inferer(inputs, self.network)
# use random flipping as data augmentation at inference
flip_pred_1 = torch.flip(self.inferer(flip_inputs_1, self.network), dims=(2,))
flip_pred_2 = torch.flip(self.inferer(flip_inputs_2, self.network), dims=(3,))
flip_pred_3 = torch.flip(self.inferer(flip_inputs_3, self.network), dims=(2, 3))
return (pred + flip_pred_1 + flip_pred_2 + flip_pred_3) / 4
# execute forward computation
self.network.eval()
with torch.no_grad():
if self.amp:
with torch.cuda.amp.autocast():
predictions = _compute_pred()
else:
predictions = _compute_pred()
return {"image": inputs, "label": targets, "pred": predictions}
evaluator = DynUNetEvaluator(
device=current_device,
val_data_loader=val_loader,
network=net,
inferer=SlidingWindowInferer2D(roi_size=patch_size, sw_batch_size=4, overlap=0.0),
post_transform=None,
key_val_metric={
"Mean_dice": MeanDice(
include_background=False,
to_onehot_y=True,
mutually_exclusive=True,
output_transform=lambda x: (x["pred"], x["label"]),
)
},
val_handlers=val_handlers,
amp=False,
)
"""
MONAI trainer
"""
print("*** Preparing the dynUNet trainer engine...\n")
# train_post_transforms = Compose(
# [
# Activationsd(keys="pred", sigmoid=True),
# ]
# )
validation_every_n_epochs = config_info['training']['validation_every_n_epochs']
epoch_len = len(train_ds) // train_loader.batch_size
validation_every_n_iters = validation_every_n_epochs * epoch_len
# define event handlers for the trainer
writer_train = SummaryWriter(log_dir=os.path.join(out_model_dir, "train"))
train_handlers = [
LrScheduleHandler(lr_scheduler=scheduler, print_lr=True),
ValidationHandler(validator=evaluator, interval=validation_every_n_iters, epoch_level=False),
StatsHandler(tag_name="train_loss", output_transform=lambda x: x["loss"]),
TensorBoardStatsHandler(summary_writer=writer_train,
log_dir=os.path.join(out_model_dir, "train"), tag_name="Loss",
output_transform=lambda x: x["loss"],
global_epoch_transform=lambda x: trainer.state.iteration),
CheckpointSaver(save_dir=out_model_dir, save_dict={"net": net, "opt": opt},
save_final=True,
save_interval=2, epoch_level=True,
n_saved=config_info['output']['max_nr_models_saved']),
]
if model_to_load is not None:
train_handlers.append(CheckpointLoader(load_path=model_to_load, load_dict={"net": net, "opt": opt}))
# define customized trainer
class DynUNetTrainer(SupervisedTrainer):
def _iteration(self, engine, batchdata):
inputs, targets = self.prepare_batch(batchdata)
inputs, targets = inputs.to(engine.state.device), targets.to(engine.state.device)
def _compute_loss(preds, label):
labels = [label] + [interpolate(label, pred.shape[2:]) for pred in preds[1:]]
return sum([0.5 ** i * self.loss_function(p, l) for i, (p, l) in enumerate(zip(preds, labels))])
self.network.train()
self.optimizer.zero_grad()
if self.amp and self.scaler is not None:
with torch.cuda.amp.autocast():
predictions = self.inferer(inputs, self.network)
loss = _compute_loss(predictions, targets)
self.scaler.scale(loss).backward()
self.scaler.step(self.optimizer)
self.scaler.update()
else:
predictions = self.inferer(inputs, self.network)
loss = _compute_loss(predictions, targets).mean()
loss.backward()
self.optimizer.step()
return {"image": inputs, "label": targets, "pred": predictions, "loss": loss.item()}
trainer = DynUNetTrainer(
device=current_device,
max_epochs=config_info['training']['nr_train_epochs'],
train_data_loader=train_loader,
network=net,
optimizer=opt,
loss_function=loss_function,
inferer=SimpleInferer(),
post_transform=None,
key_train_metric=None,
train_handlers=train_handlers,
amp=False,
)
"""
Run training
"""
print("*** Run training...")
trainer.run()
print("Done!")
def main(config):
now = datetime.now().strftime("%Y%m%d-%H:%M:%S")
# path
csv_path = config['path']['csv_path']
trained_model_path = config['path'][
'trained_model_path'] # if None, trained from scratch
training_model_folder = os.path.join(
config['path']['training_model_folder'], now) # '/path/to/folder'
if not os.path.exists(training_model_folder):
os.makedirs(training_model_folder)
logdir = os.path.join(training_model_folder, 'logs')
if not os.path.exists(logdir):
os.makedirs(logdir)
# PET CT scan params
image_shape = tuple(config['preprocessing']['image_shape']) # (x, y, z)
in_channels = config['preprocessing']['in_channels']
voxel_spacing = tuple(
config['preprocessing']
['voxel_spacing']) # (4.8, 4.8, 4.8) # in millimeter, (x, y, z)
data_augment = config['preprocessing'][
'data_augment'] # True # for training dataset only
resize = config['preprocessing']['resize'] # True # not use yet
origin = config['preprocessing']['origin'] # how to set the new origin
normalize = config['preprocessing'][
'normalize'] # True # whether or not to normalize the inputs
number_class = config['preprocessing']['number_class'] # 2
# CNN params
architecture = config['model']['architecture'] # 'unet' or 'vnet'
cnn_params = config['model'][architecture]['cnn_params']
# transform list to tuple
for key, value in cnn_params.items():
if isinstance(value, list):
cnn_params[key] = tuple(value)
# Training params
epochs = config['training']['epochs']
batch_size = config['training']['batch_size']
shuffle = config['training']['shuffle']
opt_params = config['training']["optimizer"]["opt_params"]
# Get Data
DM = DataManager(csv_path=csv_path)
train_images_paths, val_images_paths, test_images_paths = DM.get_train_val_test(
wrap_with_dict=True)
# Input preprocessing
# use data augmentation for training
train_transforms = Compose([ # read img + meta info
LoadNifti(keys=["pet_img", "ct_img", "mask_img"]),
Roi2Mask(keys=['pet_img', 'mask_img'],
method='otsu',
tval=0.0,
idx_channel=0),
ResampleReshapeAlign(target_shape=image_shape,
target_voxel_spacing=voxel_spacing,
keys=['pet_img', "ct_img", 'mask_img'],
origin='head',
origin_key='pet_img'),
Sitk2Numpy(keys=['pet_img', 'ct_img', 'mask_img']),
# user can also add other random transforms
RandAffined(keys=("pet_img", "ct_img", "mask_img"),
spatial_size=None,
prob=0.4,
rotate_range=(0, np.pi / 30, np.pi / 15),
shear_range=None,
translate_range=(10, 10, 10),
scale_range=(0.1, 0.1, 0.1),
mode=("bilinear", "bilinear", "nearest"),
padding_mode="border"),
# normalize input
ScaleIntensityRanged(
keys=["pet_img"],
a_min=0.0,
a_max=25.0,
b_min=0.0,
b_max=1.0,
clip=True,
),
ScaleIntensityRanged(
keys=["ct_img"],
a_min=-1000.0,
a_max=1000.0,
b_min=0.0,
b_max=1.0,
clip=True,
),
# Prepare for neural network
ConcatModality(keys=['pet_img', 'ct_img']),
AddChanneld(keys=["mask_img"]), # Add channel to the first axis
ToTensord(keys=["image", "mask_img"]),
])
# without data augmentation for validation
val_transforms = Compose([ # read img + meta info
LoadNifti(keys=["pet_img", "ct_img", "mask_img"]),
Roi2Mask(keys=['pet_img', 'mask_img'],
method='otsu',
tval=0.0,
idx_channel=0),
ResampleReshapeAlign(target_shape=image_shape,
target_voxel_spacing=voxel_spacing,
keys=['pet_img', "ct_img", 'mask_img'],
origin='head',
origin_key='pet_img'),
Sitk2Numpy(keys=['pet_img', 'ct_img', 'mask_img']),
# normalize input
ScaleIntensityRanged(
keys=["pet_img"],
a_min=0.0,
a_max=25.0,
b_min=0.0,
b_max=1.0,
clip=True,
),
ScaleIntensityRanged(
keys=["ct_img"],
a_min=-1000.0,
a_max=1000.0,
b_min=0.0,
b_max=1.0,
clip=True,
),
# Prepare for neural network
ConcatModality(keys=['pet_img', 'ct_img']),
AddChanneld(keys=["mask_img"]), # Add channel to the first axis
ToTensord(keys=["image", "mask_img"]),
])
# create a training data loader
train_ds = monai.data.CacheDataset(data=train_images_paths,
transform=train_transforms,
cache_rate=0.5)
# use batch_size=2 to load images to generate 2 x 4 images for network training
train_loader = monai.data.DataLoader(train_ds,
batch_size=batch_size,
shuffle=shuffle,
num_workers=2)
# create a validation data loader
val_ds = monai.data.CacheDataset(data=val_images_paths,
transform=val_transforms,
cache_rate=1.0)
val_loader = monai.data.DataLoader(val_ds,
batch_size=batch_size,
num_workers=2)
# Model
# create UNet, DiceLoss and Adam optimizer
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
net = UNet(
dimensions=3, # 3D
in_channels=in_channels,
out_channels=1,
kernel_size=5,
channels=(8, 16, 32, 64, 128),
strides=(2, 2, 2, 2),
num_res_units=2,
).to(device)
loss = monai.losses.DiceLoss(sigmoid=True, squared_pred=True)
opt = torch.optim.Adam(net.parameters(), 1e-3)
# training
val_post_transforms = Compose([
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold_values=True),
])
val_handlers = [
StatsHandler(output_transform=lambda x: None),
TensorBoardStatsHandler(log_dir="./runs/",
output_transform=lambda x: None),
# TensorBoardImageHandler(
# log_dir="./runs/",
# batch_transform=lambda x: (x["image"], x["label"]),
# output_transform=lambda x: x["pred"],
# ),
CheckpointSaver(save_dir="./runs/",
save_dict={
"net": net,
"opt": opt
},
save_key_metric=True),
]
evaluator = SupervisedEvaluator(
device=device,
val_data_loader=val_loader,
network=net,
inferer=SimpleInferer(),
post_transform=val_post_transforms,
key_val_metric={
"val_mean_dice":
MeanDice(include_background=True,
output_transform=lambda x: (x["pred"], x["label"]))
},
additional_metrics={
"val_acc":
Accuracy(output_transform=lambda x: (x["pred"], x["label"])),
"val_precision":
Precision(output_transform=lambda x: (x["pred"], x["label"])),
"val_recall":
Recall(output_transform=lambda x: (x["pred"], x["label"]))
},
val_handlers=val_handlers,
# if no FP16 support in GPU or PyTorch version < 1.6, will not enable AMP evaluation
# amp=True if monai.config.get_torch_version_tuple() >= (1, 6) else False,
)
train_post_transforms = Compose([
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold_values=True),
])
train_handlers = [
# LrScheduleHandler(lr_scheduler=lr_scheduler, print_lr=True),
ValidationHandler(validator=evaluator, interval=1, epoch_level=True),
StatsHandler(tag_name="train_loss",
output_transform=lambda x: x["loss"]),
TensorBoardStatsHandler(log_dir="./runs/",
tag_name="train_loss",
output_transform=lambda x: x["loss"]),
CheckpointSaver(save_dir="./runs/",
save_dict={
"net": net,
"opt": opt
},
save_interval=2,
epoch_level=True),
]
trainer = SupervisedTrainer(
device=device,
max_epochs=5,
train_data_loader=train_loader,
network=net,
optimizer=opt,
loss_function=loss,
prepare_batch=lambda x: (x['image'], x['mask_img']),
inferer=SimpleInferer(),
post_transform=train_post_transforms,
key_train_metric={
"train_mean_dice":
MeanDice(include_background=True,
output_transform=lambda x: (x["pred"], x["label"]))
},
additional_metrics={
"train_acc":
Accuracy(output_transform=lambda x: (x["pred"], x["label"])),
"train_precision":
Precision(output_transform=lambda x: (x["pred"], x["label"])),
"train_recall":
Recall(output_transform=lambda x: (x["pred"], x["label"]))
},
train_handlers=train_handlers,
# if no FP16 support in GPU or PyTorch version < 1.6, will not enable AMP training
amp=True if monai.config.get_torch_version_tuple() >=
(1, 6) else False,
)
trainer.run()