def test_save_resized_content(self, output_ext):
with tempfile.TemporaryDirectory() as tempdir:
# set up engine
def _train_func(engine, batch):
return torch.randint(0, 255, (8, 1, 2, 2)).float()
engine = Engine(_train_func)
# set up testing handler
saver = SegmentationSaver(output_dir=tempdir,
output_postfix="seg",
output_ext=output_ext,
scale=255)
saver.attach(engine)
data = [{
"filename_or_obj":
["testfile" + str(i) + ".nii.gz" for i in range(8)],
"spatial_shape": [(28, 28)] * 8,
"affine": [np.diag(np.ones(4)) * 5] * 8,
"original_affine": [np.diag(np.ones(4)) * 1.0] * 8,
}]
engine.run(data, max_epochs=1)
for i in range(8):
filepath = os.path.join(
"testfile" + str(i),
"testfile" + str(i) + "_seg" + output_ext)
self.assertTrue(os.path.exists(os.path.join(tempdir,
filepath)))
def test_save_resized_content(self, output_ext):
default_dir = os.path.join(".", "tempdir")
shutil.rmtree(default_dir, ignore_errors=True)
# set up engine
def _train_func(engine, batch):
return torch.randint(0, 255, (8, 1, 2, 2)).float()
engine = Engine(_train_func)
# set up testing handler
saver = SegmentationSaver(output_dir=default_dir, output_postfix="seg", output_ext=output_ext)
saver.attach(engine)
data = [
{
"filename_or_obj": ["testfile" + str(i) for i in range(8)],
"spatial_shape": [(28, 28)] * 8,
"affine": [np.diag(np.ones(4)) * 5] * 8,
"original_affine": [np.diag(np.ones(4)) * 1.0] * 8,
}
]
engine.run(data, max_epochs=1)
for i in range(8):
filepath = os.path.join("testfile" + str(i), "testfile" + str(i) + "_seg" + output_ext)
self.assertTrue(os.path.exists(os.path.join(default_dir, filepath)))
shutil.rmtree(default_dir)
def test_saved_content(self, output_ext):
with tempfile.TemporaryDirectory() as tempdir:
# set up engine
def _train_func(engine, batch):
return torch.randint(0, 255, (8, 1, 2, 2)).float()
engine = Engine(_train_func)
# set up testing handler
saver = SegmentationSaver(output_dir=tempdir,
output_postfix="seg",
output_ext=output_ext,
scale=255)
saver.attach(engine)
data = [{
"filename_or_obj":
["testfile" + str(i) + ".nii.gz" for i in range(8)],
"patch_index":
list(range(8)),
}]
engine.run(data, max_epochs=1)
for i in range(8):
filepath = os.path.join(
"testfile" + str(i),
"testfile" + str(i) + "_seg" + f"_{i}" + output_ext)
self.assertTrue(os.path.exists(os.path.join(tempdir,
filepath)))
def run_test(batch_size, img_name, seg_name, output_dir, device="cuda:0"):
ds = NiftiDataset([img_name], [seg_name], transform=AddChannel(), seg_transform=AddChannel(), image_only=False)
loader = DataLoader(ds, batch_size=1, pin_memory=torch.cuda.is_available())
net = UNet(
dimensions=3, in_channels=1, out_channels=1, channels=(4, 8, 16, 32), strides=(2, 2, 2), num_res_units=2
).to(device)
roi_size = (16, 32, 48)
sw_batch_size = batch_size
def _sliding_window_processor(_engine, batch):
net.eval()
img, seg, meta_data = batch
with torch.no_grad():
seg_probs = sliding_window_inference(img.to(device), roi_size, sw_batch_size, net, device=device)
return predict_segmentation(seg_probs)
infer_engine = Engine(_sliding_window_processor)
SegmentationSaver(
output_dir=output_dir, output_ext=".nii.gz", output_postfix="seg", batch_transform=lambda x: x[2]
).attach(infer_engine)
infer_engine.run(loader)
basename = os.path.basename(img_name)[: -len(".nii.gz")]
saved_name = os.path.join(output_dir, basename, f"{basename}_seg.nii.gz")
return saved_name
def test_saved_content(self, output_ext):
default_dir = os.path.join(".", "tempdir")
shutil.rmtree(default_dir, ignore_errors=True)
# set up engine
def _train_func(engine, batch):
return torch.zeros(8, 1, 2, 2)
engine = Engine(_train_func)
# set up testing handler
saver = SegmentationSaver(output_dir=default_dir,
output_postfix="seg",
output_ext=output_ext)
saver.attach(engine)
data = [{"filename_or_obj": ["testfile" + str(i) for i in range(8)]}]
engine.run(data, max_epochs=1)
for i in range(8):
filepath = os.path.join("testfile" + str(i),
"testfile" + str(i) + "_seg" + output_ext)
self.assertTrue(os.path.exists(os.path.join(default_dir,
filepath)))
shutil.rmtree(default_dir)
def test_saved_content(self):
default_dir = os.path.join('.', 'tempdir')
shutil.rmtree(default_dir, ignore_errors=True)
# set up engine
def _train_func(engine, batch):
return torch.zeros(8, 1, 2, 2)
engine = Engine(_train_func)
# set up testing handler
saver = SegmentationSaver(output_dir=default_dir,
output_postfix='seg',
output_ext='.nii.gz')
saver.attach(engine)
data = [{'filename_or_obj': ['testfile' + str(i) for i in range(8)]}]
engine.run(data, max_epochs=1)
for i in range(8):
filepath = os.path.join('testfile' + str(i),
'testfile' + str(i) + '_seg.nii.gz')
self.assertTrue(os.path.exists(os.path.join(default_dir,
filepath)))
shutil.rmtree(default_dir)
# 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: {
'filename_or_obj': batch['img.filename_or_obj'],
'affine': batch['img.affine']
},
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,
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():
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 run_inference_test(root_dir, model_file, device="cuda:0", amp=False, num_workers=4):
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(
[
LoadImaged(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=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)
val_postprocessing = Compose(
[
ToTensord(keys=["pred", "label"]),
Activationsd(keys="pred", sigmoid=True),
AsDiscreted(keys="pred", threshold=0.5),
KeepLargestConnectedComponentd(keys="pred", applied_labels=[1]),
# test the case that `pred` in `engine.state.output`, while `image_meta_dict` in `engine.state.batch`
SaveImaged(
keys="pred", meta_keys=PostFix.meta("image"), output_dir=root_dir, output_postfix="seg_transform"
),
]
)
val_handlers = [
StatsHandler(iteration_log=False),
CheckpointLoader(load_path=f"{model_file}", load_dict={"net": net}),
SegmentationSaver(
output_dir=root_dir,
output_postfix="seg_handler",
batch_transform=from_engine(PostFix.meta("image")),
output_transform=from_engine("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),
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"]))},
val_handlers=val_handlers,
amp=bool(amp),
)
evaluator.run()
return evaluator.state.best_metric
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)
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())
def run_inference(input_data, config_info):
"""
Pipeline to run inference with MONAI dynUNet model. The pipeline reads the input filenames, applies the required
preprocessing and creates the pytorch dataloader; it then performs evaluation on each input file using a trained
dynUNet model (random flipping augmentation is applied at inference).
It uses the dynUNet model implemented in the MONAI framework
(https://github.com/Project-MONAI/MONAI/blob/master/monai/networks/nets/dynunet.py)
which is inspired by the nnU-Net framework (https://arxiv.org/abs/1809.10486)
Inference is performed in 2D slice-by-slice, all slices are then recombined together into the 3D volume.
Args:
input_data: str or list of strings, filenames of images to be processed
config_info: dict, contains the configuration parameters to reload the trained model
"""
"""
Read input and configuration parameters
"""
val_files = create_data_list_of_dictionaries(input_data)
# print MONAI config information
logging.basicConfig(stream=sys.stdout, level=logging.INFO)
print("*** MONAI config: ")
print_config()
# print to log the parameter setups
print("*** Network inference config: ")
print(yaml.dump(config_info))
# inference params
nr_out_channels = config_info['inference']['nr_out_channels']
spacing = config_info["inference"]["spacing"]
prob_thr = config_info['inference']['probability_threshold']
model_to_load = config_info['inference']['model_to_load']
if not os.path.exists(model_to_load):
raise FileNotFoundError('Trained model not found')
patch_size = config_info["inference"]["inplane_size"] + [1]
print("Considering patch size = {}".format(patch_size))
# set up either GPU or CPU usage
if torch.cuda.is_available():
print("\n#### GPU INFORMATION ###")
print("Using device number: {}, name: {}".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))
"""
Data Preparation
"""
print("*** Preparing data ... ")
# data preprocessing for inference:
# - convert data to right format [batch, channel, dim, dim, dim]
# - resample to the training resolution in-plane (not along z)
# - apply whitening
# - convert to tensor
val_transforms = Compose([
LoadNiftid(keys=["image"]),
AddChanneld(keys=["image"]),
InPlaneSpacingd(
keys=["image"],
pixdim=spacing,
mode="bilinear",
),
NormalizeIntensityd(keys=["image"], nonzero=False, channel_wise=True),
ToTensord(keys=["image"]),
])
# create a validation data loader
val_ds = Dataset(data=val_files, transform=val_transforms)
val_loader = DataLoader(val_ds,
batch_size=1,
num_workers=config_info['device']['num_workers'])
def prepare_batch(batchdata):
assert isinstance(batchdata,
dict), "prepare_batch expects dictionary input data."
return ((batchdata["image"],
batchdata["label"]) if "label" in batchdata else
(batchdata["image"], None))
"""
Network preparation
"""
print("*** Preparing 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])
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)
"""
Set ignite evaluator to perform inference
"""
print("*** Preparing evaluator ... ")
if nr_out_channels == 1:
do_sigmoid = True
do_softmax = False
elif nr_out_channels > 1:
do_sigmoid = False
do_softmax = True
else:
raise Exception("incompatible number of output channels")
print("Using sigmoid={} and softmax={} as final activation".format(
do_sigmoid, do_softmax))
val_post_transforms = Compose([
Activationsd(keys="pred", sigmoid=do_sigmoid, softmax=do_softmax),
AsDiscreted(keys="pred",
argmax=True,
threshold_values=True,
logit_thresh=prob_thr),
KeepLargestConnectedComponentd(keys="pred", applied_labels=1)
])
val_handlers = [
StatsHandler(output_transform=lambda x: None),
CheckpointLoader(load_path=model_to_load,
load_dict={"net": net},
map_location=torch.device('cpu')),
SegmentationSaver(
output_dir=config_info['output']['out_dir'],
output_ext='.nii.gz',
output_postfix=config_info['output']['out_postfix'],
batch_transform=lambda batch: batch["image_meta_dict"],
output_transform=lambda output: output["pred"],
),
]
# Define customized evaluator
class DynUNetEvaluator(SupervisedEvaluator):
def _iteration(self, engine, batchdata):
inputs, targets = self.prepare_batch(batchdata)
inputs = inputs.to(engine.state.device)
if targets is not None:
targets = 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,
prepare_batch=prepare_batch,
inferer=SlidingWindowInferer2D(roi_size=patch_size,
sw_batch_size=4,
overlap=0.0),
post_transform=val_post_transforms,
val_handlers=val_handlers,
amp=False,
)
"""
Run inference
"""
print("*** Running evaluator ... ")
evaluator.run()
print("Done!")
return
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 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(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)]
# 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
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)
val_post_transforms = Compose([
Activationsd(keys="pred", output_postfix="act", sigmoid=True),
AsDiscreted(keys="pred_act",
output_postfix="dis",
threshold_values=True),
KeepLargestConnectedComponentd(keys="pred_act_dis",
applied_values=[1],
output_postfix=None),
])
val_handlers = [
StatsHandler(output_transform=lambda x: None),
CheckpointLoader(load_path="./runs/net_key_metric=0.9101.pth",
load_dict={"net": net}),
SegmentationSaver(
output_dir="./runs/",
batch_transform=lambda x: {
"filename_or_obj": x["image.filename_or_obj"],
"affine": x["image.affine"],
"original_affine": x["image.original_affine"],
"spatial_shape": x["image.spatial_shape"],
},
output_transform=lambda x: x["pred_act_dis"],
),
]
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_act_dis"], x["label"]))
},
additional_metrics={
"val_acc":
Accuracy(
output_transform=lambda x: (x["pred_act_dis"], x["label"]))
},
val_handlers=val_handlers,
)
evaluator.run()
shutil.rmtree(tempdir)
