Total Variation (TV)¶

Module Interface¶

class torchmetrics.TotalVariation(reduction='sum', **kwargs)[source]

Computes Total Variation loss (TV).

As input to forward and update the metric accepts the following input

img (Tensor): A tensor of shape (N, C, H, W) consisting of images

As output of forward and compute the metric returns the following output

sdi (Tensor): if reduction!='none' returns float scalar tensor with average TV value over sample else returns tensor of shape (N,) with TV values per sample

Parameters

reduction¶ (Literal[‘mean’, ‘sum’, ‘none’, None]) –
a method to reduce metric score over samples
- 'mean': takes the mean over samples
- 'sum': takes the sum over samples
- None or 'none': return the score per sample
kwargs¶ (Any) – Additional keyword arguments, see Advanced metric settings for more info.

Raises

ValueError – If reduction is not one of 'sum', 'mean', 'none' or None

Example

>>> import torch
>>> from torchmetrics import TotalVariation
>>> _ = torch.manual_seed(42)
>>> tv = TotalVariation()
>>> img = torch.rand(5, 3, 28, 28)
>>> tv(img)
tensor(7546.8018)

Initializes internal Module state, shared by both nn.Module and ScriptModule.

Functional Interface¶

torchmetrics.functional.total_variation(img, reduction='sum')[source]

Computes total variation loss.

Parameters

img¶ (Tensor) – A Tensor of shape (N, C, H, W) consisting of images
reduction¶ (Literal[‘mean’, ‘sum’, ‘none’, None]) –
a method to reduce metric score over samples.
- 'mean': takes the mean over samples
- 'sum': takes the sum over samples
- None or 'none': return the score per sample

Return type

Tensor

Returns

A loss scalar value containing the total variation

Raises

ValueError – If reduction is not one of 'sum', 'mean', 'none' or None
RuntimeError – If img is not 4D tensor

Example

>>> import torch
>>> from torchmetrics.functional import total_variation
>>> _ = torch.manual_seed(42)
>>> img = torch.rand(5, 3, 28, 28)
>>> total_variation(img)
tensor(7546.8018)