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) return predict_segmentation(seg_probs)
def _sliding_window_processor(_engine, batch): img, seg, meta_data = batch with eval_mode(net): seg_probs = sliding_window_inference(img.to(device), roi_size, sw_batch_size, net, device=device) return predict_segmentation(seg_probs)
def _sliding_window_processor(_engine, batch): img = batch[0] # first item from ImageDataset is the input image with eval_mode(net): seg_probs = sliding_window_inference(img.to(device), roi_size, sw_batch_size, net, device=device) return predict_segmentation(seg_probs)
def main(tempdir): monai.config.print_config() logging.basicConfig(stream=sys.stdout, level=logging.INFO) # create a temporary directory and 40 random image, mask pairs print(f"generating synthetic data to {tempdir} (this may take a while)") for i in range(40): im, seg = create_test_image_3d(128, 128, 128, num_seg_classes=1) n = nib.Nifti1Image(im, np.eye(4)) nib.save(n, os.path.join(tempdir, f"im{i:d}.nii.gz")) n = nib.Nifti1Image(seg, np.eye(4)) nib.save(n, os.path.join(tempdir, f"seg{i:d}.nii.gz")) images = sorted(glob(os.path.join(tempdir, "im*.nii.gz"))) segs = sorted(glob(os.path.join(tempdir, "seg*.nii.gz"))) # define transforms for image and segmentation train_imtrans = Compose([ ScaleIntensity(), AddChannel(), RandSpatialCrop((96, 96, 96), random_size=False), 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 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) loss = monai.losses.DiceLoss(sigmoid=True) lr = 1e-3 opt = torch.optim.Adam(net.parameters(), lr) # Ignite trainer expects batch=(img, seg) and returns output=loss at every iteration, # user can add output_transform to return other values, like: y_pred, y, etc. trainer = create_supervised_trainer(net, opt, loss, device, False) # adding checkpoint handler to save models (network params and optimizer stats) during training checkpoint_handler = ModelCheckpoint("./runs_array/", "net", n_saved=10, require_empty=False) trainer.add_event_handler(event_name=Events.EPOCH_COMPLETED, handler=checkpoint_handler, to_save={ "net": net, "opt": opt }) # StatsHandler prints loss at every iteration and print metrics at every epoch, # we don't set metrics for trainer here, so just print loss, user can also customize print functions # and can use output_transform to convert engine.state.output if it's not a loss value train_stats_handler = StatsHandler(name="trainer") 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(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) 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(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(): 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 main(): 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) 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 = 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(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_100.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) print(state) shutil.rmtree(tempdir)