def test_misconfig(self, input_params):
with self.assertRaisesRegex(ValueError, "compatib"):
dice_metric = MeanDice(**input_params)
y_pred = torch.Tensor([[0, 1], [1, 0]])
y = torch.ones((2, 1))
dice_metric.update([y_pred, y])
def test_compute(self, input_params, expected_avg, details_shape):
dice_metric = MeanDice(**input_params)
# set up engine
def _val_func(engine, batch):
pass
engine = Engine(_val_func)
dice_metric.attach(engine=engine, name="mean_dice")
# test input a list of channel-first tensor
y_pred = [torch.Tensor([[0], [1]]), torch.Tensor([[1], [0]])]
y = torch.Tensor([[[0], [1]], [[0], [1]]])
engine.state.output = {"pred": y_pred, "label": y}
engine.fire_event(Events.ITERATION_COMPLETED)
y_pred = [torch.Tensor([[0], [1]]), torch.Tensor([[1], [0]])]
y = torch.Tensor([[[0], [1]], [[1], [0]]])
engine.state.output = {"pred": y_pred, "label": y}
engine.fire_event(Events.ITERATION_COMPLETED)
engine.fire_event(Events.EPOCH_COMPLETED)
torch.testing.assert_allclose(engine.state.metrics["mean_dice"],
expected_avg)
self.assertTupleEqual(
tuple(engine.state.metric_details["mean_dice"].shape),
details_shape)
def val_key_metric(self, context: Context):
all_metrics = dict()
all_metrics["val_mean_dice"] = MeanDice(output_transform=from_engine(
["pred", "label"]),
include_background=False)
for key_label in self._labels:
if key_label != "background":
all_metrics[key_label + "_dice"] = MeanDice(
output_transform=from_engine(
["pred_" + key_label, "label_" + key_label]),
include_background=False)
return all_metrics
def region_wise_metrics(regions, metric, prefix, keys=("pred", "label")):
all_metrics = dict()
all_metrics[metric] = MeanDice(output_transform=from_engine(keys),
include_background=False)
if regions:
labels = regions if isinstance(regions, dict) else {
name: idx
for idx, name in enumerate(regions, start=1)
}
for name, idx in labels.items():
all_metrics[f"{prefix}_{name}_dice"] = MeanDice(
output_transform=from_engine_idx(keys, idx),
include_background=False,
)
return all_metrics
def test_compute(self, input_params, expected_avg):
dice_metric = MeanDice(**input_params)
y_pred = torch.Tensor([[[0], [1]], [[1], [0]]])
y = torch.Tensor([[[0], [1]], [[0], [1]]])
dice_metric.update([y_pred, y])
y_pred = torch.Tensor([[[0], [1]], [[1], [0]]])
y = torch.Tensor([[[0], [1]], [[1], [0]]])
dice_metric.update([y_pred, y])
avg_dice = dice_metric.compute()
self.assertAlmostEqual(avg_dice, expected_avg, places=4)
def test_shape_mismatch(self, input_params, _expected_avg, _details_shape):
dice_metric = MeanDice(**input_params)
with self.assertRaises((AssertionError, ValueError)):
y_pred = torch.Tensor([[0, 1], [1, 0]])
y = torch.ones((2, 3))
dice_metric.update([y_pred, y])
with self.assertRaises((AssertionError, ValueError)):
y_pred = torch.Tensor([[0, 1], [1, 0]])
y = torch.ones((3, 2))
dice_metric.update([y_pred, y])
def test_compute(self, input_params, expected_avg, details_shape):
dice_metric = MeanDice(**input_params)
# set up engine
def _val_func(engine, batch):
pass
engine = Engine(_val_func)
dice_metric.attach(engine=engine, name="mean_dice")
y_pred = torch.Tensor([[[0], [1]], [[1], [0]]])
y = torch.Tensor([[[0], [1]], [[0], [1]]])
dice_metric.update([y_pred, y])
y_pred = [torch.Tensor([[0], [1]]), torch.Tensor([[1], [0]])]
y = [torch.Tensor([[0], [1]]), torch.Tensor([[1], [0]])]
dice_metric.update([y_pred, y])
avg_dice = dice_metric.compute()
self.assertAlmostEqual(avg_dice, expected_avg, places=4)
self.assertTupleEqual(
tuple(engine.state.metric_details["mean_dice"].shape),
details_shape)
def ensemble_evaluate(post_transforms, models):
evaluator = EnsembleEvaluator(
device=device,
val_data_loader=test_loader,
pred_keys=opt.pred_keys,
networks=models,
inferer=SlidingWindowInferer(roi_size=opt.patch_size,
sw_batch_size=opt.batch_size,
overlap=0.5),
post_transform=post_transforms,
key_val_metric={
"test_mean_dice":
MeanDice(
include_background=True,
output_transform=lambda x: (x["pred"], x["label"]),
)
},
)
evaluator.run()
def train(args):
# load hyper parameters
task_id = args.task_id
fold = args.fold
val_output_dir = "./runs_{}_fold{}_{}/".format(task_id, fold,
args.expr_name)
log_filename = "nnunet_task{}_fold{}.log".format(task_id, fold)
log_filename = os.path.join(val_output_dir, log_filename)
interval = args.interval
learning_rate = args.learning_rate
max_epochs = args.max_epochs
multi_gpu_flag = args.multi_gpu
amp_flag = args.amp
lr_decay_flag = args.lr_decay
sw_batch_size = args.sw_batch_size
tta_val = args.tta_val
batch_dice = args.batch_dice
window_mode = args.window_mode
eval_overlap = args.eval_overlap
local_rank = args.local_rank
determinism_flag = args.determinism_flag
determinism_seed = args.determinism_seed
if determinism_flag:
set_determinism(seed=determinism_seed)
if local_rank == 0:
print("Using deterministic training.")
# transforms
train_batch_size = data_loader_params[task_id]["batch_size"]
if multi_gpu_flag:
dist.init_process_group(backend="nccl", init_method="env://")
device = torch.device(f"cuda:{local_rank}")
torch.cuda.set_device(device)
else:
device = torch.device("cuda")
properties, val_loader = get_data(args, mode="validation")
_, train_loader = get_data(args, batch_size=train_batch_size, mode="train")
# produce the network
checkpoint = args.checkpoint
net = get_network(properties, task_id, val_output_dir, checkpoint)
net = net.to(device)
if multi_gpu_flag:
net = DistributedDataParallel(module=net,
device_ids=[device],
find_unused_parameters=True)
optimizer = torch.optim.SGD(
net.parameters(),
lr=learning_rate,
momentum=0.99,
weight_decay=3e-5,
nesterov=True,
)
scheduler = torch.optim.lr_scheduler.LambdaLR(
optimizer, lr_lambda=lambda epoch: (1 - epoch / max_epochs)**0.9)
# produce evaluator
val_handlers = [
StatsHandler(output_transform=lambda x: None),
CheckpointSaver(save_dir=val_output_dir,
save_dict={"net": net},
save_key_metric=True),
]
evaluator = DynUNetEvaluator(
device=device,
val_data_loader=val_loader,
network=net,
n_classes=len(properties["labels"]),
inferer=SlidingWindowInferer(
roi_size=patch_size[task_id],
sw_batch_size=sw_batch_size,
overlap=eval_overlap,
mode=window_mode,
),
post_transform=None,
key_val_metric={
"val_mean_dice":
MeanDice(
include_background=False,
output_transform=lambda x: (x["pred"], x["label"]),
)
},
val_handlers=val_handlers,
amp=amp_flag,
tta_val=tta_val,
)
# produce trainer
loss = DiceCELoss(to_onehot_y=True, softmax=True, batch=batch_dice)
train_handlers = []
if lr_decay_flag:
train_handlers += [
LrScheduleHandler(lr_scheduler=scheduler, print_lr=True)
]
train_handlers += [
ValidationHandler(validator=evaluator,
interval=interval,
epoch_level=True),
StatsHandler(tag_name="train_loss",
output_transform=lambda x: x["loss"]),
]
trainer = DynUNetTrainer(
device=device,
max_epochs=max_epochs,
train_data_loader=train_loader,
network=net,
optimizer=optimizer,
loss_function=loss,
inferer=SimpleInferer(),
post_transform=None,
key_train_metric=None,
train_handlers=train_handlers,
amp=amp_flag,
)
# run
logger = logging.getLogger()
formatter = logging.Formatter(
"%(asctime)s - %(name)s - %(levelname)s - %(message)s")
# Setup file handler
fhandler = logging.FileHandler(log_filename)
fhandler.setLevel(logging.INFO)
fhandler.setFormatter(formatter)
# Configure stream handler for the cells
chandler = logging.StreamHandler()
chandler.setLevel(logging.INFO)
chandler.setFormatter(formatter)
# Add both handlers
if local_rank == 0:
logger.addHandler(fhandler)
logger.addHandler(chandler)
logger.setLevel(logging.INFO)
trainer.run()
def validation(args):
# load hyper parameters
task_id = args.task_id
sw_batch_size = args.sw_batch_size
tta_val = args.tta_val
window_mode = args.window_mode
eval_overlap = args.eval_overlap
multi_gpu_flag = args.multi_gpu
local_rank = args.local_rank
amp = args.amp
# produce the network
checkpoint = args.checkpoint
val_output_dir = "./runs_{}_fold{}_{}/".format(task_id, args.fold,
args.expr_name)
if multi_gpu_flag:
dist.init_process_group(backend="nccl", init_method="env://")
device = torch.device(f"cuda:{local_rank}")
torch.cuda.set_device(device)
else:
device = torch.device("cuda")
properties, val_loader = get_data(args, mode="validation")
net = get_network(properties, task_id, val_output_dir, checkpoint)
net = net.to(device)
if multi_gpu_flag:
net = DistributedDataParallel(module=net,
device_ids=[device],
find_unused_parameters=True)
n_classes = len(properties["labels"])
net.eval()
evaluator = DynUNetEvaluator(
device=device,
val_data_loader=val_loader,
network=net,
n_classes=n_classes,
inferer=SlidingWindowInferer(
roi_size=patch_size[task_id],
sw_batch_size=sw_batch_size,
overlap=eval_overlap,
mode=window_mode,
),
post_transform=None,
key_val_metric={
"val_mean_dice":
MeanDice(
include_background=False,
output_transform=lambda x: (x["pred"], x["label"]),
)
},
additional_metrics=None,
amp=amp,
tta_val=tta_val,
)
evaluator.run()
if local_rank == 0:
print(evaluator.state.metrics)
results = evaluator.state.metric_details["val_mean_dice"]
if n_classes > 2:
for i in range(n_classes - 1):
print("mean dice for label {} is {}".format(
i + 1, results[:, i].mean()))
def train(index):
# ---------- Build the nn-Unet network ------------
if opt.resolution is None:
sizes, spacings = opt.patch_size, opt.spacing
else:
sizes, spacings = opt.patch_size, opt.resolution
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])
net = monai.networks.nets.DynUNet(
spatial_dims=3,
in_channels=opt.in_channels,
out_channels=opt.out_channels,
kernel_size=kernels,
strides=strides,
upsample_kernel_size=strides[1:],
res_block=True,
# act=act_type,
# norm=Norm.BATCH,
).to(device)
from torch.autograd import Variable
from torchsummaryX import summary
data = Variable(
torch.randn(int(opt.batch_size), int(opt.in_channels),
int(opt.patch_size[0]), int(opt.patch_size[1]),
int(opt.patch_size[2]))).cuda()
out = net(data)
summary(net, data)
print("out size: {}".format(out.size()))
# if opt.preload is not None:
# net.load_state_dict(torch.load(opt.preload))
# ---------- ------------------------ ------------
optim = torch.optim.Adam(net.parameters(), lr=opt.lr)
lr_scheduler = torch.optim.lr_scheduler.LambdaLR(
optim, lr_lambda=lambda epoch: (1 - epoch / opt.epochs)**0.9)
loss_function = monai.losses.DiceCELoss(sigmoid=True)
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),
CheckpointSaver(save_dir="./runs/",
save_dict={"net": net},
save_key_metric=True),
]
evaluator = SupervisedEvaluator(
device=device,
val_data_loader=val_loaders[index],
network=net,
inferer=SlidingWindowInferer(roi_size=opt.patch_size,
sw_batch_size=opt.batch_size,
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"]),
)
},
val_handlers=val_handlers)
train_post_transforms = Compose([
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold_values=True),
# KeepLargestConnectedComponentd(keys="pred", applied_labels=[1]),
])
train_handlers = [
ValidationHandler(validator=evaluator,
interval=5,
epoch_level=True),
LrScheduleHandler(lr_scheduler=lr_scheduler, print_lr=True),
StatsHandler(tag_name="train_loss",
output_transform=lambda x: x["loss"]),
CheckpointSaver(save_dir="./runs/",
save_dict={
"net": net,
"opt": optim
},
save_final=True,
epoch_level=True),
]
trainer = SupervisedTrainer(
device=device,
max_epochs=opt.epochs,
train_data_loader=train_loaders[index],
network=net,
optimizer=optim,
loss_function=loss_function,
inferer=SimpleInferer(),
post_transform=train_post_transforms,
amp=False,
train_handlers=train_handlers,
)
trainer.run()
return net
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 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 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 = [{
Keys.IMAGE: img,
Keys.LABEL: seg
} for img, seg in zip(images[:20], segs[:20])]
val_files = [{
Keys.IMAGE: img,
Keys.LABEL: seg
} for img, seg in zip(images[-20:], segs[-20:])]
# define transforms for image and segmentation
train_transforms = Compose([
LoadNiftid(keys=[Keys.IMAGE, Keys.LABEL]),
AsChannelFirstd(keys=[Keys.IMAGE, Keys.LABEL], channel_dim=-1),
ScaleIntensityd(keys=[Keys.IMAGE, Keys.LABEL]),
RandCropByPosNegLabeld(keys=[Keys.IMAGE, Keys.LABEL],
label_key=Keys.LABEL,
size=[96, 96, 96],
pos=1,
neg=1,
num_samples=4),
RandRotate90d(keys=[Keys.IMAGE, Keys.LABEL],
prob=0.5,
spatial_axes=[0, 2]),
ToTensord(keys=[Keys.IMAGE, Keys.LABEL]),
])
val_transforms = Compose([
LoadNiftid(keys=[Keys.IMAGE, Keys.LABEL]),
AsChannelFirstd(keys=[Keys.IMAGE, Keys.LABEL], channel_dim=-1),
ScaleIntensityd(keys=[Keys.IMAGE, Keys.LABEL]),
ToTensord(keys=[Keys.IMAGE, Keys.LABEL]),
])
# 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)
# create a validation data loader
val_ds = monai.data.Dataset(data=val_files, transform=val_transforms)
val_loader = DataLoader(val_ds,
batch_size=1,
num_workers=4,
collate_fn=list_data_collate)
# create UNet, DiceLoss and Adam optimizer
device = torch.device("cuda:0")
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(do_sigmoid=True)
opt = torch.optim.Adam(net.parameters(), 1e-3)
val_handlers = [StatsHandler(output_transform=lambda x: None)]
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),
val_handlers=val_handlers,
key_val_metric={
"val_mean_dice":
MeanDice(include_background=True,
add_sigmoid=True,
output_transform=lambda x: (x[Keys.PRED], x[Keys.LABEL]))
},
additional_metrics=None,
)
train_handlers = [
ValidationHandler(validator=evaluator, interval=2, epoch_level=True),
StatsHandler(tag_name="train_loss",
output_transform=lambda x: x[Keys.INFO][Keys.LOSS]),
]
trainer = SupervisedTrainer(
device=device,
max_epochs=5,
train_data_loader=train_loader,
network=net,
optimizer=opt,
loss_function=loss,
inferer=SimpleInferer(),
train_handlers=train_handlers,
amp=False,
key_train_metric=None,
)
trainer.run()
shutil.rmtree(tempdir)
def val_key_metric(self, context):
return {
self.VAL_KEY_METRIC:
MeanDice(output_transform=from_engine(["pred", "label"]))
}
def train_key_metric(self, context: Context):
return {
self.TRAIN_KEY_METRIC:
MeanDice(output_transform=from_engine(["pred", "label"]))
}
def main():
monai.config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
tempdir = tempfile.mkdtemp()
print(f"generating synthetic data to {tempdir} (this may take a while)")
for i in range(5):
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"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")))
val_files = [{"img": img, "seg": seg} for img, seg in zip(images, segs)]
# define transforms for image and segmentation
val_transforms = Compose([
LoadNiftid(keys=["img", "seg"]),
AsChannelFirstd(keys=["img", "seg"], channel_dim=-1),
ScaleIntensityd(keys=["img", "seg"]),
ToTensord(keys=["img", "seg"]),
])
val_ds = monai.data.Dataset(data=val_files, transform=val_transforms)
device = torch.device("cuda:0")
net = UNet(
dimensions=3,
in_channels=1,
out_channels=1,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
)
net.to(device)
# define sliding window size and batch size for windows inference
roi_size = (96, 96, 96)
sw_batch_size = 4
def _sliding_window_processor(engine, batch):
net.eval()
with torch.no_grad():
val_images, val_labels = batch["img"].to(device), batch["seg"].to(
device)
seg_probs = sliding_window_inference(val_images, roi_size,
sw_batch_size, net)
return seg_probs, val_labels
evaluator = Engine(_sliding_window_processor)
# add evaluation metric to the evaluator engine
MeanDice(sigmoid=True, to_onehot_y=False).attach(evaluator, "Mean_Dice")
# StatsHandler prints loss at every iteration and print metrics at every epoch,
# we don't need to print loss for evaluator, so just print metrics, user can also customize print functions
val_stats_handler = StatsHandler(
name="evaluator",
output_transform=lambda x:
None, # no need to print loss value, so disable per iteration output
)
val_stats_handler.attach(evaluator)
# convert the necessary metadata from batch data
SegmentationSaver(
output_dir="tempdir",
output_ext=".nii.gz",
output_postfix="seg",
name="evaluator",
batch_transform=lambda batch: batch["img_meta_dict"],
output_transform=lambda output: predict_segmentation(output[0]),
).attach(evaluator)
# the model was trained by "unet_training_dict" example
CheckpointLoader(load_path="./runs/net_checkpoint_50.pth",
load_dict={
"net": net
}).attach(evaluator)
# sliding window inference for one image at every iteration
val_loader = DataLoader(val_ds,
batch_size=1,
num_workers=4,
collate_fn=list_data_collate,
pin_memory=torch.cuda.is_available())
state = evaluator.run(val_loader)
print(state)
shutil.rmtree(tempdir)
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 main():
config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
tempdir = tempfile.mkdtemp()
print('generating synthetic data to {} (this may take a while)'.format(tempdir))
for i in range(5):
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
imtrans = Compose([ScaleIntensity(), AddChannel(), ToTensor()])
segtrans = Compose([AddChannel(), ToTensor()])
ds = NiftiDataset(images, segs, transform=imtrans, seg_transform=segtrans, image_only=False)
device = torch.device('cuda:0')
net = UNet(
dimensions=3,
in_channels=1,
out_channels=1,
channels=(16, 32, 64, 128, 256),
strides=(2, 2, 2, 2),
num_res_units=2,
)
net.to(device)
# define sliding window size and batch size for windows inference
roi_size = (96, 96, 96)
sw_batch_size = 4
def _sliding_window_processor(engine, batch):
net.eval()
with torch.no_grad():
val_images, val_labels = batch[0].to(device), batch[1].to(device)
seg_probs = sliding_window_inference(val_images, roi_size, sw_batch_size, net)
return seg_probs, val_labels
evaluator = Engine(_sliding_window_processor)
# add evaluation metric to the evaluator engine
MeanDice(add_sigmoid=True, to_onehot_y=False).attach(evaluator, 'Mean_Dice')
# StatsHandler prints loss at every iteration and print metrics at every epoch,
# we don't need to print loss for evaluator, so just print metrics, user can also customize print functions
val_stats_handler = StatsHandler(
name='evaluator',
output_transform=lambda x: None # no need to print loss value, so disable per iteration output
)
val_stats_handler.attach(evaluator)
# for the array data format, assume the 3rd item of batch data is the meta_data
file_saver = SegmentationSaver(
output_dir='tempdir', output_ext='.nii.gz', output_postfix='seg', name='evaluator',
batch_transform=lambda x: x[2], output_transform=lambda output: predict_segmentation(output[0]))
file_saver.attach(evaluator)
# the model was trained by "unet_training_array" example
ckpt_saver = CheckpointLoader(load_path='./runs/net_checkpoint_50.pth', load_dict={'net': net})
ckpt_saver.attach(evaluator)
# sliding window inference for one image at every iteration
loader = DataLoader(ds, batch_size=1, num_workers=1, pin_memory=torch.cuda.is_available())
state = evaluator.run(loader)
shutil.rmtree(tempdir)
def _sliding_window_processor(engine, batch):
net.eval()
with torch.no_grad():
val_images, val_labels = batch['img'].to(device), batch['seg'].to(
device)
seg_probs = sliding_window_inference(val_images, roi_size,
sw_batch_size, net)
return seg_probs, val_labels
evaluator = Engine(_sliding_window_processor)
# add evaluation metric to the evaluator engine
MeanDice(add_sigmoid=True, to_onehot_y=False).attach(evaluator, 'Mean_Dice')
# StatsHandler prints loss at every iteration and print metrics at every epoch,
# we don't need to print loss for evaluator, so just print metrics, user can also customize print functions
val_stats_handler = StatsHandler(
name='evaluator',
output_transform=lambda x:
None # no need to print loss value, so disable per iteration output
)
val_stats_handler.attach(evaluator)
# convert the necessary metadata from batch data
SegmentationSaver(
output_dir='tempdir',
output_ext='.nii.gz',
output_postfix='seg',
def train(data_folder=".", model_folder="runs"):
"""run a training pipeline."""
images = sorted(glob.glob(os.path.join(data_folder, "*_ct.nii.gz")))
labels = sorted(glob.glob(os.path.join(data_folder, "*_seg.nii.gz")))
logging.info(
f"training: image/label ({len(images)}) folder: {data_folder}")
amp = True # auto. mixed precision
keys = ("image", "label")
train_frac, val_frac = 0.8, 0.2
n_train = int(train_frac * len(images)) + 1
n_val = min(len(images) - n_train, int(val_frac * len(images)))
logging.info(
f"training: train {n_train} val {n_val}, folder: {data_folder}")
train_files = [{
keys[0]: img,
keys[1]: seg
} for img, seg in zip(images[:n_train], labels[:n_train])]
val_files = [{
keys[0]: img,
keys[1]: seg
} for img, seg in zip(images[-n_val:], labels[-n_val:])]
# create a training data loader
batch_size = 2
logging.info(f"batch size {batch_size}")
train_transforms = get_xforms("train", keys)
train_ds = monai.data.CacheDataset(data=train_files,
transform=train_transforms)
train_loader = monai.data.DataLoader(
train_ds,
batch_size=batch_size,
shuffle=True,
num_workers=2,
pin_memory=torch.cuda.is_available(),
)
# create a validation data loader
val_transforms = get_xforms("val", keys)
val_ds = monai.data.CacheDataset(data=val_files, transform=val_transforms)
val_loader = monai.data.DataLoader(
val_ds,
batch_size=
1, # image-level batch to the sliding window method, not the window-level batch
num_workers=2,
pin_memory=torch.cuda.is_available(),
)
# create BasicUNet, DiceLoss and Adam optimizer
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
net = get_net().to(device)
max_epochs, lr, momentum = 500, 1e-4, 0.95
logging.info(f"epochs {max_epochs}, lr {lr}, momentum {momentum}")
opt = torch.optim.Adam(net.parameters(), lr=lr)
# create evaluator (to be used to measure model quality during training
val_post_transform = monai.transforms.Compose([
AsDiscreted(keys=("pred", "label"),
argmax=(True, False),
to_onehot=True,
n_classes=2)
])
val_handlers = [
ProgressBar(),
CheckpointSaver(save_dir=model_folder,
save_dict={"net": net},
save_key_metric=True,
key_metric_n_saved=3),
]
evaluator = monai.engines.SupervisedEvaluator(
device=device,
val_data_loader=val_loader,
network=net,
inferer=get_inferer(),
post_transform=val_post_transform,
key_val_metric={
"val_mean_dice":
MeanDice(include_background=False,
output_transform=lambda x: (x["pred"], x["label"]))
},
val_handlers=val_handlers,
amp=amp,
)
# evaluator as an event handler of the trainer
train_handlers = [
ValidationHandler(validator=evaluator, interval=1, epoch_level=True),
StatsHandler(tag_name="train_loss",
output_transform=lambda x: x["loss"]),
]
trainer = monai.engines.SupervisedTrainer(
device=device,
max_epochs=max_epochs,
train_data_loader=train_loader,
network=net,
optimizer=opt,
loss_function=DiceCELoss(),
inferer=get_inferer(),
key_train_metric=None,
train_handlers=train_handlers,
amp=amp,
)
trainer.run()
def main(tempdir):
config.print_config()
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
print(f"generating synthetic data to {tempdir} (this may take a while)")
for i in range(5):
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
imtrans = Compose([ScaleIntensity(), AddChannel(), ToTensor()])
segtrans = Compose([AddChannel(), ToTensor()])
ds = ImageDataset(images,
segs,
transform=imtrans,
seg_transform=segtrans,
image_only=False)
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
net = 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)
# define sliding window size and batch size for windows inference
roi_size = (96, 96, 96)
sw_batch_size = 4
post_trans = Compose(
[Activations(sigmoid=True),
AsDiscrete(threshold_values=True)])
def _sliding_window_processor(engine, batch):
net.eval()
with torch.no_grad():
val_images, val_labels = batch[0].to(device), batch[1].to(device)
seg_probs = sliding_window_inference(val_images, roi_size,
sw_batch_size, net)
seg_probs = post_trans(seg_probs)
return seg_probs, val_labels
evaluator = Engine(_sliding_window_processor)
# add evaluation metric to the evaluator engine
MeanDice().attach(evaluator, "Mean_Dice")
# StatsHandler prints loss at every iteration and print metrics at every epoch,
# we don't need to print loss for evaluator, so just print metrics, user can also customize print functions
val_stats_handler = StatsHandler(
name="evaluator",
output_transform=lambda x:
None, # no need to print loss value, so disable per iteration output
)
val_stats_handler.attach(evaluator)
# for the array data format, assume the 3rd item of batch data is the meta_data
file_saver = SegmentationSaver(
output_dir="tempdir",
output_ext=".nii.gz",
output_postfix="seg",
name="evaluator",
batch_transform=lambda x: x[2],
output_transform=lambda output: output[0],
)
file_saver.attach(evaluator)
# the model was trained by "unet_training_array" example
ckpt_saver = CheckpointLoader(
load_path="./runs_array/net_checkpoint_100.pt", load_dict={"net": net})
ckpt_saver.attach(evaluator)
# sliding window inference for one image at every iteration
loader = DataLoader(ds,
batch_size=1,
num_workers=1,
pin_memory=torch.cuda.is_available())
state = evaluator.run(loader)
print(state)
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 train(data_folder=".", model_folder="runs", continue_training=False):
"""run a training pipeline."""
#/== files for synthesis
path_parent = Path(
'/content/drive/My Drive/Datasets/covid19/COVID-19-20_augs_cea/')
path_synthesis = Path(
path_parent /
'CeA_BASE_grow=1_bg=-1.00_step=-1.0_scale=-1.0_seed=1.0_ch0_1=-1_ch1_16=-1_ali_thr=0.1'
)
scans_syns = os.listdir(path_synthesis)
decreasing_sequence = get_decreasing_sequence(255, splits=20)
keys2 = ("image", "label", "synthetic_lesion")
# READ THE SYTHETIC HEALTHY TEXTURE
path_synthesis_old = '/content/drive/My Drive/Datasets/covid19/results/cea_synthesis/patient0/'
texture_orig = np.load(f'{path_synthesis_old}texture.npy.npz')
texture_orig = texture_orig.f.arr_0
texture = texture_orig + np.abs(np.min(texture_orig)) + .07
texture = np.pad(texture, ((100, 100), (100, 100)), mode='reflect')
print(f'type(texture) = {type(texture)}, {np.shape(texture)}')
#==/
images = sorted(glob.glob(os.path.join(data_folder,
"*_ct.nii.gz"))[:10]) #OMM
labels = sorted(glob.glob(os.path.join(data_folder,
"*_seg.nii.gz"))[:10]) #OMM
logging.info(
f"training: image/label ({len(images)}) folder: {data_folder}")
amp = True # auto. mixed precision
keys = ("image", "label")
train_frac, val_frac = 0.8, 0.2
n_train = int(train_frac * len(images)) + 1
n_val = min(len(images) - n_train, int(val_frac * len(images)))
logging.info(
f"training: train {n_train} val {n_val}, folder: {data_folder}")
train_files = [{
keys[0]: img,
keys[1]: seg
} for img, seg in zip(images[:n_train], labels[:n_train])]
val_files = [{
keys[0]: img,
keys[1]: seg
} for img, seg in zip(images[-n_val:], labels[-n_val:])]
# create a training data loader
batch_size = 1 # XX was 2
logging.info(f"batch size {batch_size}")
train_transforms = get_xforms("synthesis", keys, keys2, path_synthesis,
decreasing_sequence, scans_syns, texture)
train_ds = monai.data.CacheDataset(data=train_files,
transform=train_transforms)
train_loader = monai.data.DataLoader(
train_ds,
batch_size=batch_size,
shuffle=True,
num_workers=2,
pin_memory=torch.cuda.is_available(),
# collate_fn=pad_list_data_collate,
)
# create a validation data loader
val_transforms = get_xforms("val", keys)
val_ds = monai.data.CacheDataset(data=val_files, transform=val_transforms)
val_loader = monai.data.DataLoader(
val_ds,
batch_size=
1, # image-level batch to the sliding window method, not the window-level batch
num_workers=2,
pin_memory=torch.cuda.is_available(),
)
# create BasicUNet, DiceLoss and Adam optimizer
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
net = get_net().to(device)
# if continue training
if continue_training:
ckpts = sorted(glob.glob(os.path.join(model_folder, "*.pt")))
ckpt = ckpts[-1]
logging.info(f"continue training using {ckpt}.")
net.load_state_dict(torch.load(ckpt, map_location=device))
# max_epochs, lr, momentum = 500, 1e-4, 0.95
max_epochs, lr, momentum = 20, 1e-4, 0.95 #OMM
logging.info(f"epochs {max_epochs}, lr {lr}, momentum {momentum}")
opt = torch.optim.Adam(net.parameters(), lr=lr)
# create evaluator (to be used to measure model quality during training
val_post_transform = monai.transforms.Compose([
AsDiscreted(keys=("pred", "label"),
argmax=(True, False),
to_onehot=True,
n_classes=2)
])
val_handlers = [
ProgressBar(),
MetricsSaver(save_dir="./metrics_val", metrics="*"),
CheckpointSaver(save_dir=model_folder,
save_dict={"net": net},
save_key_metric=True,
key_metric_n_saved=6),
]
evaluator = monai.engines.SupervisedEvaluator(
device=device,
val_data_loader=val_loader,
network=net,
inferer=get_inferer(),
post_transform=val_post_transform,
key_val_metric={
"val_mean_dice":
MeanDice(include_background=False,
output_transform=lambda x: (x["pred"], x["label"]))
},
val_handlers=val_handlers,
amp=amp,
)
# evaluator as an event handler of the trainer
train_handlers = [
ValidationHandler(validator=evaluator, interval=1, epoch_level=True),
# MetricsSaver(save_dir="./metrics_train", metrics="*"),
StatsHandler(tag_name="train_loss",
output_transform=lambda x: x["loss"]),
]
trainer = monai.engines.SupervisedTrainer(
device=device,
max_epochs=max_epochs,
train_data_loader=train_loader,
network=net,
optimizer=opt,
loss_function=DiceCELoss(),
inferer=get_inferer(),
key_train_metric=None,
train_handlers=train_handlers,
amp=amp,
)
trainer.run()
def evaluate(args):
if args.local_rank == 0 and not os.path.exists(args.dir):
# create 16 random image, mask paris for evaluation
print(f"generating synthetic data to {args.dir} (this may take a while)")
os.makedirs(args.dir)
# set random seed to generate same random data for every node
np.random.seed(seed=0)
for i in range(16):
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(args.dir, f"img{i:d}.nii.gz"))
n = nib.Nifti1Image(seg, np.eye(4))
nib.save(n, os.path.join(args.dir, f"seg{i:d}.nii.gz"))
# initialize the distributed evaluation process, every GPU runs in a process
dist.init_process_group(backend="nccl", init_method="env://")
images = sorted(glob(os.path.join(args.dir, "img*.nii.gz")))
segs = sorted(glob(os.path.join(args.dir, "seg*.nii.gz")))
val_files = [{"image": img, "label": seg} for img, seg in zip(images, segs)]
# define transforms for image and segmentation
val_transforms = Compose(
[
LoadImaged(keys=["image", "label"]),
AsChannelFirstd(keys=["image", "label"], channel_dim=-1),
ScaleIntensityd(keys="image"),
ToTensord(keys=["image", "label"]),
]
)
# create a evaluation data loader
val_ds = Dataset(data=val_files, transform=val_transforms)
# create a evaluation data sampler
val_sampler = DistributedSampler(val_ds, shuffle=False)
# sliding window inference need to input 1 image in every iteration
val_loader = DataLoader(val_ds, batch_size=1, shuffle=False, num_workers=2, pin_memory=True, sampler=val_sampler)
# create UNet, DiceLoss and Adam optimizer
device = torch.device(f"cuda:{args.local_rank}")
torch.cuda.set_device(device)
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)
# wrap the model with DistributedDataParallel module
net = DistributedDataParallel(net, device_ids=[device])
val_post_transforms = Compose(
[
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold_values=True),
KeepLargestConnectedComponentd(keys="pred", applied_labels=[1]),
]
)
val_handlers = [
CheckpointLoader(
load_path="./runs/checkpoint_epoch=4.pt",
load_dict={"net": net},
# config mapping to expected GPU device
map_location={"cuda:0": f"cuda:{args.local_rank}"},
),
]
if dist.get_rank() == 0:
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
val_handlers.extend(
[
StatsHandler(output_transform=lambda x: None),
SegmentationSaver(
output_dir="./runs/",
batch_transform=lambda batch: batch["image_meta_dict"],
output_transform=lambda output: output["pred"],
),
]
)
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"]),
device=device,
)
},
additional_metrics={"val_acc": Accuracy(output_transform=lambda x: (x["pred"], x["label"]), device=device)},
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,
)
evaluator.run()
dist.destroy_process_group()
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)
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(5):
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"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")))
val_files = [{"image": img, "label": seg} for img, seg in zip(images, segs)]
# model file path
model_file = glob("./runs/net_key_metric*")[0]
# define transforms for image and segmentation
val_transforms = Compose(
[
LoadNiftid(keys=["image", "label"]),
AsChannelFirstd(keys=["image", "label"], channel_dim=-1),
ScaleIntensityd(keys="image"),
ToTensord(keys=["image", "label"]),
]
)
# create a validation data loader
val_ds = monai.data.Dataset(data=val_files, transform=val_transforms)
val_loader = monai.data.DataLoader(val_ds, batch_size=1, num_workers=4)
# 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)
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),
CheckpointLoader(load_path=model_file, load_dict={"net": net}),
SegmentationSaver(
output_dir="./runs/",
batch_transform=lambda batch: batch["image_meta_dict"],
output_transform=lambda output: output["pred"],
),
]
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.config.get_torch_version_tuple() >= (1, 6) else False,
)
evaluator.run()
def run_inference_test(root_dir, model_file, device="cuda:0", amp=False):
images = sorted(glob(os.path.join(root_dir, "im*.nii.gz")))
segs = sorted(glob(os.path.join(root_dir, "seg*.nii.gz")))
val_files = [{
"image": img,
"label": seg
} for img, seg in zip(images, segs)]
# define transforms for image and segmentation
val_transforms = Compose([
LoadNiftid(keys=["image", "label"]),
AsChannelFirstd(keys=["image", "label"], channel_dim=-1),
ScaleIntensityd(keys=["image", "label"]),
ToTensord(keys=["image", "label"]),
])
# create a validation data loader
val_ds = monai.data.Dataset(data=val_files, transform=val_transforms)
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)
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),
CheckpointLoader(load_path=f"{model_file}", load_dict={"net": net}),
SegmentationSaver(
output_dir=root_dir,
batch_transform=lambda batch: batch["image_meta_dict"],
output_transform=lambda output: output["pred"],
),
]
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,
)
evaluator.run()
return evaluator.state.best_metric
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 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
