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SequentialLabels

SequentialLabels

Bases: LabelTransform

Remap labels in a label map so they become consecutive.

For example, if a label map has labels (0, 3, 5), then this will apply a RemapLabels transform with remapping={3: 1, 5: 2}, and therefore the output image will have labels (0, 1, 2).

Examples:

>>> import torch
>>> import torchio as tio
>>> def get_image(*labels):
...     tensor = torch.as_tensor(labels).reshape(1, 1, 1, -1)
...     image = tio.LabelMap(tensor=tensor)
...     return image
...
>>> img_with_bg = get_image(0, 5, 10)
>>> transform = tio.SequentialLabels()
>>> transform(img_with_bg).data
tensor([[[[0, 1, 2]]]])
>>> img_without_bg = get_image(7, 11, 99)
>>> transform(img_without_bg).data
tensor([[[[0, 1, 2]]]])
Note

This transformation is always fully invertible .

Warning

The background is typically represented with the label 0. There will be zeros in the output image even if they are none in the input.

Parameters:

Name Type Description Default
masking_method TypeMaskingMethod None
**kwargs

See Transform for additional keyword arguments.

{}

__call__(data)

Transform data and return a result of the same type.

Parameters:

Name Type Description Default
data InputType

Instance of torchio.Subject, 4D torch.Tensor or numpy.ndarray with dimensions \((C, W, H, D)\), where \(C\) is the number of channels and \(W, H, D\) are the spatial dimensions. If the input is a tensor, the affine matrix will be set to identity. Other valid input types are a SimpleITK image, a torchio.Image, a NiBabel Nifti1 image or a dict. The output type is the same as the input type.

required

get_base_args()

Provides easy access to the arguments used to instantiate the base class (Transform) of any transform.

This method is particularly useful when a new transform can be represented as a variant of an existing transform (e.g. all random transforms), allowing for seamless instantiation of the existing transform with the same arguments as the new transform during apply_transform.

Note

The p argument (probability of applying the transform) is excluded to avoid multiplying the probability of both existing and new transform.

add_base_args(arguments, overwrite_on_existing=False)

Add the init args to existing arguments

validate_keys_sequence(keys, name) staticmethod

Ensure that the input is not a string but a sequence of strings.

to_hydra_config()

Return a dictionary representation of the transform for Hydra instantiation.