Transforms2D

Set of operators to perform data augmentation on 2D image tensors.

class CenterCrop(size: Union[int, Tuple[int, int]], align_corners: bool = True, resample: Union[str, int, <unknown>.Resample] = 'BILINEAR', return_transform: bool = False, p: float = 1.0, keepdim: bool = False, cropping_mode: str = 'slice')[source]

Crops a given image tensor at the center.

Parameters
  • p (float) – probability of applying the transformation for the whole batch. Default value is 1.

  • size (Tuple[int, int] or int) – Desired output size (out_h, out_w) of the crop. If integer, out_h = out_w = size. If Tuple[int, int], out_h = size[0], out_w = size[1].

  • return_transform (bool) – if True return the matrix describing the transformation applied to each. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

  • cropping_mode (str) – The used algorithm to crop. slice will use advanced slicing to extract the tensor based on the sampled indices. resample will use warp_affine using the affine transformation to extract and resize at once. Use slice for efficiency, or resample for proper differentiability. Default: slice.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, out_h, out_w)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> inputs = torch.randn(1, 1, 4, 4)
>>> inputs
tensor([[[[-1.1258, -1.1524, -0.2506, -0.4339],
          [ 0.8487,  0.6920, -0.3160, -2.1152],
          [ 0.3223, -1.2633,  0.3500,  0.3081],
          [ 0.1198,  1.2377,  1.1168, -0.2473]]]])
>>> aug = CenterCrop(2, p=1.)
>>> aug(inputs)
tensor([[[[ 0.6920, -0.3160],
          [-1.2633,  0.3500]]]])
class ColorJitter(brightness: Union[torch.Tensor, float, Tuple[float, float], List[float]] = 0.0, contrast: Union[torch.Tensor, float, Tuple[float, float], List[float]] = 0.0, saturation: Union[torch.Tensor, float, Tuple[float, float], List[float]] = 0.0, hue: Union[torch.Tensor, float, Tuple[float, float], List[float]] = 0.0, return_transform: bool = False, same_on_batch: bool = False, p: float = 1.0, keepdim: bool = False)[source]

Applies a random transformation to the brightness, contrast, saturation and hue of a tensor image.

Parameters
  • p (float) – probability of applying the transformation. Default value is 1.

  • brightness (float or tuple) – Default value is 0.

  • contrast (float or tuple) – Default value is 0.

  • saturation (float or tuple) – Default value is 0.

  • hue (float or tuple) – Default value is 0.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> inputs = torch.ones(1, 3, 3, 3)
>>> aug = ColorJitter(0.1, 0.1, 0.1, 0.1, p=1.)
>>> aug(inputs)
tensor([[[[0.9993, 0.9993, 0.9993],
          [0.9993, 0.9993, 0.9993],
          [0.9993, 0.9993, 0.9993]],
<BLANKLINE>
         [[0.9993, 0.9993, 0.9993],
          [0.9993, 0.9993, 0.9993],
          [0.9993, 0.9993, 0.9993]],
<BLANKLINE>
         [[0.9993, 0.9993, 0.9993],
          [0.9993, 0.9993, 0.9993],
          [0.9993, 0.9993, 0.9993]]]])
class GaussianBlur(kernel_size: Tuple[int, int], sigma: Tuple[float, float], border_type: str = 'reflect', return_transform: bool = False, same_on_batch: bool = False, p: float = 0.5)[source]

Apply gaussian blur given tensor image or a batch of tensor images randomly.

Parameters
  • kernel_size (Tuple[int, int]) – the size of the kernel.

  • sigma (Tuple[float, float]) – the standard deviation of the kernel.

  • border_type (str) – the padding mode to be applied before convolving. The expected modes are: 'constant', 'reflect', 'replicate' or 'circular'. Default: 'reflect'.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • p (float) – probability of applying the transformation. Default value is 0.5.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.rand(1, 1, 5, 5)
>>> blur = GaussianBlur((3, 3), (0.1, 2.0), p=1.)
>>> blur(input)
tensor([[[[0.6699, 0.4645, 0.3193, 0.1741, 0.1955],
          [0.5422, 0.6657, 0.6261, 0.6527, 0.5195],
          [0.3826, 0.2638, 0.1902, 0.1620, 0.2141],
          [0.6329, 0.6732, 0.5634, 0.4037, 0.2049],
          [0.8307, 0.6753, 0.7147, 0.5768, 0.7097]]]])
class RandomAffine(degrees: Union[torch.Tensor, float, Tuple[float, float]], translate: Union[torch.Tensor, Tuple[float, float], None] = None, scale: Union[torch.Tensor, Tuple[float, float], Tuple[float, float, float, float], None] = None, shear: Union[torch.Tensor, float, Tuple[float, float], None] = None, resample: Union[str, int, <unknown>.Resample] = 'BILINEAR', return_transform: bool = False, same_on_batch: bool = False, align_corners: bool = False, padding_mode: Union[str, int, <unknown>.SamplePadding] = 'ZEROS', p: float = 0.5, keepdim: bool = False)[source]

Applies a random 2D affine transformation to a tensor image.

The transformation is computed so that the image center is kept invariant.

Parameters
  • p (float) – probability of applying the transformation. Default value is 0.5.

  • degrees (float or tuple) – Range of degrees to select from. If degrees is a number instead of sequence like (min, max), the range of degrees will be (-degrees, +degrees). Set to 0 to deactivate rotations.

  • translate (tuple, optional) – tuple of maximum absolute fraction for horizontal and vertical translations. For example translate=(a, b), then horizontal shift is randomly sampled in the range -img_width * a < dx < img_width * a and vertical shift is randomly sampled in the range -img_height * b < dy < img_height * b. Will not translate by default.

  • scale (tuple, optional) – scaling factor interval. If (a, b) represents isotropic scaling, the scale is randomly sampled from the range a <= scale <= b. If (a, b, c, d), the scale is randomly sampled from the range a <= scale_x <= b, c <= scale_y <= d. Will keep original scale by default.

  • shear (sequence or float, optional) – Range of degrees to select from. If float, a shear parallel to the x axis in the range (-shear, +shear) will be apllied. If (a, b), a shear parallel to the x axis in the range (-shear, +shear) will be apllied. If (a, b, c, d), then x-axis shear in (shear[0], shear[1]) and y-axis shear in (shear[2], shear[3]) will be applied. Will not apply shear by default.

  • resample (int, str or kornia.Resample) – resample mode from “nearest” (0) or “bilinear” (1). Default: Resample.BILINEAR.

  • padding_mode (int, str or kornia.SamplePadding) – padding mode from “zeros” (0), “border” (1) or “refection” (2). Default: SamplePadding.ZEROS.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each. Default: False.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • align_corners (bool) – interpolation flag. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.rand(1, 1, 3, 3)
>>> aug = RandomAffine((-15., 20.), return_transform=True, p=1.)
>>> aug(input)
(tensor([[[[0.3961, 0.7310, 0.1574],
          [0.1781, 0.3074, 0.5648],
          [0.4804, 0.8379, 0.4234]]]]), tensor([[[ 0.9923, -0.1241,  0.1319],
         [ 0.1241,  0.9923, -0.1164],
         [ 0.0000,  0.0000,  1.0000]]]))
class RandomCrop(size: Tuple[int, int], padding: Union[int, Tuple[int, int], Tuple[int, int, int, int], None] = None, pad_if_needed: Optional[bool] = False, fill: int = 0, padding_mode: str = 'constant', resample: Union[str, int, <unknown>.Resample] = 'BILINEAR', return_transform: bool = False, same_on_batch: bool = False, align_corners: bool = True, p: float = 1.0, keepdim: bool = False, cropping_mode: str = 'slice')[source]

Crops random patches of a tensor image on a given size.

Parameters
  • p (float) – probability of applying the transformation for the whole batch. Default value is 1.0.

  • size (Tuple[int, int]) – Desired output size (out_h, out_w) of the crop. Must be Tuple[int, int], then out_h = size[0], out_w = size[1].

  • padding (int or sequence, optional) – Optional padding on each border of the image. Default is None, i.e no padding. If a sequence of length 4 is provided, it is used to pad left, top, right, bottom borders respectively. If a sequence of length 2 is provided, it is used to pad left/right, top/bottom borders, respectively.

  • pad_if_needed (boolean) – It will pad the image if smaller than the desired size to avoid raising an exception. Since cropping is done after padding, the padding seems to be done at a random offset.

  • fill – Pixel fill value for constant fill. Default is 0. If a tuple of length 3, it is used to fill R, G, B channels respectively. This value is only used when the padding_mode is constant

  • padding_mode – Type of padding. Should be: constant, edge, reflect or symmetric. Default is constant.

  • resample (int, str or kornia.Resample) – Default: Resample.BILINEAR

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False

  • align_corners (bool) – interpolation flag. Default: True.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

  • cropping_mode (str) – The used algorithm to crop. slice will use advanced slicing to extract the tensor based on the sampled indices. resample will use warp_affine using the affine transformation to extract and resize at once. Use slice for efficiency, or resample for proper differentiability. Default: slice.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, out_h, out_w)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> _ = torch.manual_seed(0)
>>> inputs = torch.arange(1*1*3*3.).view(1, 1, 3, 3)
>>> aug = RandomCrop((2, 2), p=1.)
>>> aug(inputs)
tensor([[[[3., 4.],
          [6., 7.]]]])
class RandomErasing(scale: Union[torch.Tensor, Tuple[float, float]] = (0.02, 0.33), ratio: Union[torch.Tensor, Tuple[float, float]] = (0.3, 3.3), value: float = 0.0, return_transform: bool = False, same_on_batch: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Erases a random rectangle of a tensor image according to a probability p value.

The operator removes image parts and fills them with zero values at a selected rectangle for each of the images in the batch.

The rectangle will have an area equal to the original image area multiplied by a value uniformly sampled between the range [scale[0], scale[1]) and an aspect ratio sampled between [ratio[0], ratio[1])

Parameters
  • p (float) – probability that the random erasing operation will be performed. Default value is 0.5.

  • scale (Tuple[float, float]) – range of proportion of erased area against input image.

  • ratio (Tuple[float, float]) – range of aspect ratio of erased area.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> inputs = torch.ones(1, 1, 3, 3)
>>> rec_er = RandomErasing((.4, .8), (.3, 1/.3), p=0.5)
>>> rec_er(inputs)
tensor([[[[1., 0., 0.],
          [1., 0., 0.],
          [1., 0., 0.]]]])
class RandomGrayscale(return_transform: bool = False, same_on_batch: bool = False, p: float = 0.1, keepdim: bool = False)[source]

Applies random transformation to Grayscale according to a probability p value.

Parameters
  • p (float) – probability of the image to be transformed to grayscale. Default value is 0.1.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> inputs = torch.randn((1, 3, 3, 3))
>>> rec_er = RandomGrayscale(p=1.0)
>>> rec_er(inputs)
tensor([[[[-1.1344, -0.1330,  0.1517],
          [-0.0791,  0.6711, -0.1413],
          [-0.1717, -0.9023,  0.0819]],
<BLANKLINE>
         [[-1.1344, -0.1330,  0.1517],
          [-0.0791,  0.6711, -0.1413],
          [-0.1717, -0.9023,  0.0819]],
<BLANKLINE>
         [[-1.1344, -0.1330,  0.1517],
          [-0.0791,  0.6711, -0.1413],
          [-0.1717, -0.9023,  0.0819]]]])
class RandomHorizontalFlip(return_transform: bool = None, same_on_batch: bool = False, p: float = 0.5, p_batch: float = 1.0, keepdim: bool = False)[source]

Applies a random horizontal flip to a tensor image or a batch of tensor images with a given probability.

Input should be a tensor of shape (C, H, W) or a batch of tensors \((B, C, H, W)\). If Input is a tuple it is assumed that the first element contains the aforementioned tensors and the second, the corresponding transformation matrix that has been applied to them. In this case the module will Horizontally flip the tensors and concatenate the corresponding transformation matrix to the previous one. This is especially useful when using this functionality as part of an nn.Sequential module.

Parameters
  • p (float) – probability of the image being flipped. Default value is 0.5

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> input = torch.tensor([[[[0., 0., 0.],
...                         [0., 0., 0.],
...                         [0., 1., 1.]]]])
>>> seq = nn.Sequential(RandomHorizontalFlip(p=1.0, return_transform=True),
...                     RandomHorizontalFlip(p=1.0, return_transform=True))
>>> seq(input)
(tensor([[[[0., 0., 0.],
          [0., 0., 0.],
          [0., 1., 1.]]]]), tensor([[[1., 0., 0.],
         [0., 1., 0.],
         [0., 0., 1.]]]))
class RandomVerticalFlip(return_transform: bool = None, same_on_batch: bool = False, p: float = 0.5, p_batch: float = 1.0, keepdim: bool = False)[source]

Applies a random vertical flip to a tensor image or a batch of tensor images with a given probability.

Parameters
  • p (float) – probability of the image being flipped. Default value is 0.5

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> input = torch.tensor([[[[0., 0., 0.],
...                         [0., 0., 0.],
...                         [0., 1., 1.]]]])
>>> seq = RandomVerticalFlip(p=1.0, return_transform=True)
>>> seq(input)
(tensor([[[[0., 1., 1.],
          [0., 0., 0.],
          [0., 0., 0.]]]]), tensor([[[ 1.,  0.,  0.],
         [ 0., -1.,  2.],
         [ 0.,  0.,  1.]]]))
class RandomMotionBlur(kernel_size: Union[int, Tuple[int, int]], angle: Union[torch.Tensor, float, Tuple[float, float]], direction: Union[torch.Tensor, float, Tuple[float, float]], border_type: Union[int, str, <unknown>.BorderType] = 'CONSTANT', resample: Union[str, int, <unknown>.Resample] = 'NEAREST', return_transform: bool = False, same_on_batch: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Perform motion blur on 2D images (4D tensor).

Parameters
  • p (float) – probability of applying the transformation. Default value is 0.5.

  • kernel_size (int or Tuple[int, int]) – motion kernel size (odd and positive). If int, the kernel will have a fixed size. If Tuple[int, int], it will randomly generate the value from the range batch-wisely.

  • angle (float or Tuple[float, float]) – angle of the motion blur in degrees (anti-clockwise rotation). If float, it will generate the value from (-angle, angle).

  • direction (float or Tuple[float, float]) – forward/backward direction of the motion blur. Lower values towards -1.0 will point the motion blur towards the back (with angle provided via angle), while higher values towards 1.0 will point the motion blur forward. A value of 0.0 leads to a uniformly (but still angled) motion blur. If float, it will generate the value from (-direction, direction). If Tuple[int, int], it will randomly generate the value from the range.

  • border_type (int, str or kornia.BorderType) – the padding mode to be applied before convolving. CONSTANT = 0, REFLECT = 1, REPLICATE = 2, CIRCULAR = 3. Default: BorderType.CONSTANT.

  • resample (int, str or kornia.Resample) – Default: Resample.NEAREST.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Please set resample to 'bilinear' if more meaningful gradients wanted.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.ones(1, 1, 5, 5)
>>> motion_blur = RandomMotionBlur(3, 35., 0.5, p=1.)
>>> motion_blur(input)
tensor([[[[0.5773, 1.0000, 1.0000, 1.0000, 0.7561],
          [0.5773, 1.0000, 1.0000, 1.0000, 0.7561],
          [0.5773, 1.0000, 1.0000, 1.0000, 0.7561],
          [0.5773, 1.0000, 1.0000, 1.0000, 0.7561],
          [0.5773, 1.0000, 1.0000, 1.0000, 0.7561]]]])
class RandomPerspective(distortion_scale: Union[torch.Tensor, float] = 0.5, resample: Union[str, int, <unknown>.Resample] = 'BILINEAR', return_transform: bool = False, same_on_batch: bool = False, align_corners: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Applies a random perspective transformation to an image tensor with a given probability.

Parameters
  • p (float) – probability of the image being perspectively transformed. Default value is 0.5.

  • distortion_scale (float) – it controls the degree of distortion and ranges from 0 to 1. Default value is 0.5.

  • resample (int, str or kornia.Resample) – Default: Resample.BILINEAR.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each. Default: False.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • align_corners (bool) – interpolation flag. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> inputs= torch.tensor([[[[1., 0., 0.],
...                         [0., 1., 0.],
...                         [0., 0., 1.]]]])
>>> aug = RandomPerspective(0.5, p=0.5)
>>> aug(inputs)
tensor([[[[0.0000, 0.2289, 0.0000],
          [0.0000, 0.4800, 0.0000],
          [0.0000, 0.0000, 0.0000]]]])
class RandomResizedCrop(size: Tuple[int, int], scale: Union[torch.Tensor, Tuple[float, float]] = (0.08, 1.0), ratio: Union[torch.Tensor, Tuple[float, float]] = (0.75, 1.3333333333333333), resample: Union[str, int, <unknown>.Resample] = 'BILINEAR', return_transform: bool = False, same_on_batch: bool = False, align_corners: bool = True, p: float = 1.0, keepdim: bool = False, cropping_mode: str = 'slice')[source]

Crops random patches in an image tensor and resizes to a given size.

Parameters
  • size (Tuple[int, int]) – Desired output size (out_h, out_w) of each edge. Must be Tuple[int, int], then out_h = size[0], out_w = size[1].

  • scale – range of size of the origin size cropped.

  • ratio – range of aspect ratio of the origin aspect ratio cropped.

  • resample (int, str or kornia.Resample) – Default: Resample.BILINEAR.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • align_corners (bool) – interpolation flag. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

  • cropping_mode (str) – The used algorithm to crop. slice will use advanced slicing to extract the tensor based on the sampled indices. resample will use warp_affine using the affine transformation to extract and resize at once. Use slice for efficiency, or resample for proper differentiability. Default: slice.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, out_h, out_w)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Example

>>> rng = torch.manual_seed(0)
>>> inputs = torch.tensor([[[0., 1., 2.],
...                         [3., 4., 5.],
...                         [6., 7., 8.]]])
>>> aug = RandomResizedCrop(size=(3, 3), scale=(3., 3.), ratio=(2., 2.), p=1.)
>>> aug(inputs)
tensor([[[[1.0000, 1.5000, 2.0000],
          [4.0000, 4.5000, 5.0000],
          [7.0000, 7.5000, 8.0000]]]])
class RandomRotation(degrees: Union[torch.Tensor, float, Tuple[float, float], List[float]], resample: Union[str, int, <unknown>.Resample] = 'BILINEAR', return_transform: bool = False, same_on_batch: bool = False, align_corners: bool = True, p: float = 0.5, keepdim: bool = False)[source]

Applies a random rotation to a tensor image or a batch of tensor images given an amount of degrees.

Parameters
  • p (float) – probability of applying the transformation. Default value is 0.5.

  • degrees (sequence or float or tensor) – range of degrees to select from. If degrees is a number the range of degrees to select from will be (-degrees, +degrees).

  • resample (int, str or kornia.Resample) – Default: Resample.BILINEAR.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • align_corners (bool) – interpolation flag. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.tensor([[1., 0., 0., 2.],
...                       [0., 0., 0., 0.],
...                       [0., 1., 2., 0.],
...                       [0., 0., 1., 2.]])
>>> seq = RandomRotation(degrees=45.0, return_transform=True, p=1.)
>>> seq(input)
(tensor([[[[0.9824, 0.0088, 0.0000, 1.9649],
          [0.0000, 0.0029, 0.0000, 0.0176],
          [0.0029, 1.0000, 1.9883, 0.0000],
          [0.0000, 0.0088, 1.0117, 1.9649]]]]), tensor([[[ 1.0000, -0.0059,  0.0088],
         [ 0.0059,  1.0000, -0.0088],
         [ 0.0000,  0.0000,  1.0000]]]))
class RandomSolarize(thresholds: Union[torch.Tensor, float, Tuple[float, float], List[float]] = 0.1, additions: Union[torch.Tensor, float, Tuple[float, float], List[float]] = 0.1, same_on_batch: bool = False, return_transform: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Solarize given tensor image or a batch of tensor images randomly.

Parameters
  • p (float) – probability of applying the transformation. Default value is 0.5.

  • thresholds (float or tuple) – Default value is 0.1. If float x, threshold will be generated from (0.5 - x, 0.5 + x). If tuple (x, y), threshold will be generated from (x, y).

  • additions (float or tuple) – Default value is 0.1. If float x, addition will be generated from (-x, x). If tuple (x, y), addition will be generated from (x, y).

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.rand(1, 1, 5, 5)
>>> solarize = RandomSolarize(0.1, 0.1, p=1.)
>>> solarize(input)
tensor([[[[0.4132, 0.1412, 0.1790, 0.2226, 0.3980],
          [0.2754, 0.4194, 0.0130, 0.4538, 0.2771],
          [0.4394, 0.4923, 0.1129, 0.2594, 0.3844],
          [0.3909, 0.2118, 0.1094, 0.2516, 0.3728],
          [0.2278, 0.0000, 0.4876, 0.0353, 0.5100]]]])
class RandomPosterize(bits: Union[int, Tuple[int, int], torch.Tensor] = 3, same_on_batch: bool = False, return_transform: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Posterize given tensor image or a batch of tensor images randomly.

Parameters
  • p (float) – probability of applying the transformation. Default value is 0.5.

  • bits (int or tuple) – Integer that ranged from (0, 8], in which 0 gives black image and 8 gives the original. If int x, bits will be generated from (x, 8). If tuple (x, y), bits will be generated from (x, y). Default value is 3.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.rand(1, 1, 5, 5)
>>> posterize = RandomPosterize(3, p=1.)
>>> posterize(input)
tensor([[[[0.4706, 0.7529, 0.0627, 0.1255, 0.2824],
          [0.6275, 0.4706, 0.8784, 0.4392, 0.6275],
          [0.3451, 0.3765, 0.0000, 0.1569, 0.2824],
          [0.5020, 0.6902, 0.7843, 0.1569, 0.2510],
          [0.6588, 0.9098, 0.3765, 0.8471, 0.4078]]]])
class RandomSharpness(sharpness: Union[torch.Tensor, float, Tuple[float, float]] = 0.5, same_on_batch: bool = False, return_transform: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Sharpen given tensor image or a batch of tensor images randomly.

Parameters
  • p (float) – probability of applying the transformation. Default value is 0.5.

  • sharpness (float or tuple) – factor of sharpness strength. Must be above 0. Default value is 0.5.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.rand(1, 1, 5, 5)
>>> sharpness = RandomSharpness(1., p=1.)
>>> sharpness(input)
tensor([[[[0.4963, 0.7682, 0.0885, 0.1320, 0.3074],
          [0.6341, 0.4810, 0.7367, 0.4177, 0.6323],
          [0.3489, 0.4428, 0.1562, 0.2443, 0.2939],
          [0.5185, 0.6462, 0.7050, 0.2288, 0.2823],
          [0.6816, 0.9152, 0.3971, 0.8742, 0.4194]]]])
class RandomEqualize(same_on_batch: bool = False, return_transform: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Equalize given tensor image or a batch of tensor images randomly.

Parameters
  • p (float) – Probability to equalize an image. Default value is 0.5.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, H, W)\) or \((B, C, H, W)\), Optional: \((B, 3, 3)\)

  • Output: \((B, C, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 3, 3)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.rand(1, 1, 5, 5)
>>> equalize = RandomEqualize(p=1.)
>>> equalize(input)
tensor([[[[0.4963, 0.7682, 0.0885, 0.1320, 0.3074],
          [0.6341, 0.4901, 0.8964, 0.4556, 0.6323],
          [0.3489, 0.4017, 0.0223, 0.1689, 0.2939],
          [0.5185, 0.6977, 0.8000, 0.1610, 0.2823],
          [0.6816, 0.9152, 0.3971, 0.8742, 0.4194]]]])
class RandomMixUp(lambda_val: Union[torch.Tensor, Tuple[float, float], None] = None, same_on_batch: bool = False, p: float = 1.0, keepdim: bool = False)[source]

Apply MixUp augmentation to a batch of tensor images.

Implemention for mixup: BEYOND EMPIRICAL RISK MINIMIZATION [ZnYNDLP18].

The function returns (inputs, labels), in which the inputs is the tensor that contains the mixup images while the labels is a \((B, 3)\) tensor that contains (label_batch, label_permuted_batch, lambda) for each image.

The implementation is on top of the following repository: https://github.com/hongyi-zhang/mixup/blob/master/cifar/utils.py.

The loss and accuracy are computed as:

def loss_mixup(y, logits):
    criterion = F.cross_entropy
    loss_a = criterion(logits, y[:, 0].long(), reduction='none')
    loss_b = criterion(logits, y[:, 1].long(), reduction='none')
    return ((1 - y[:, 2]) * loss_a + y[:, 2] * loss_b).mean()
def acc_mixup(y, logits):
    pred = torch.argmax(logits, dim=1).to(y.device)
    return (1 - y[:, 2]) * pred.eq(y[:, 0]).float() + y[:, 2] * pred.eq(y[:, 1]).float()
Parameters
  • p (float) – probability for applying an augmentation to a batch. This param controls the augmentation probabilities batch-wisely.

  • lambda_val (float or torch.Tensor, optional) – min-max value of mixup strength. Default is 0-1.

  • same_on_batch (bool) – apply the same transformation across the batch. This flag will not maintain permutation order. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False

Inputs:
  • Input image tensors, shape of \((B, C, H, W)\).

  • Label: raw labels, shape of \((B)\).

Returns

  • Adjusted image, shape of \((B, C, H, W)\).

  • Raw labels, permuted labels and lambdas for each mix, shape of \((B, 3)\).

Return type

Tuple[torch.Tensor, torch.Tensor]

Note

This implementation would randomly mixup images in a batch. Ideally, the larger batch size would be preferred.

Examples

>>> rng = torch.manual_seed(1)
>>> input = torch.rand(2, 1, 3, 3)
>>> label = torch.tensor([0, 1])
>>> mixup = RandomMixUp()
>>> mixup(input, label)
(tensor([[[[0.7576, 0.2793, 0.4031],
          [0.7347, 0.0293, 0.7999],
          [0.3971, 0.7544, 0.5695]]],
<BLANKLINE>
<BLANKLINE>
        [[[0.4388, 0.6387, 0.5247],
          [0.6826, 0.3051, 0.4635],
          [0.4550, 0.5725, 0.4980]]]]), tensor([[0.0000, 0.0000, 0.1980],
        [1.0000, 1.0000, 0.4162]]))
class RandomCutMix(height: int, width: int, num_mix: int = 1, cut_size: Union[torch.Tensor, Tuple[float, float], None] = None, beta: Union[float, torch.Tensor, None] = None, same_on_batch: bool = False, p: float = 1.0, keepdim: bool = False)[source]

Apply CutMix augmentation to a batch of tensor images.

Implemention for CutMix: Regularization Strategy to Train Strong Classifiers with Localizable Features [YHO+19].

The function returns (inputs, labels), in which the inputs is the tensor that contains the mixup images while the labels is a \((\text{num_mixes}, B, 3)\) tensor that contains (label_permuted_batch, lambda) for each cutmix.

The implementation referred to the following repository: https://github.com/clovaai/CutMix-PyTorch.

The onehot label may be computed as:

def onehot(size, target):
    vec = torch.zeros(size, dtype=torch.float32)
    vec[target] = 1.
    return vec
def cutmix_label(labels, out_labels, size):
    lb_onehot = onehot(size, labels)
    for out_label in out_labels:
        label_permuted_batch, lam = out_label[:, 0], out_label[:, 1]
        label_permuted_onehot = onehot(size, label_permuted_batch)
        lb_onehot = lb_onehot * lam + label_permuted_onehot * (1. - lam)
    return lb_onehot
Parameters
  • height (int) – the width of the input image.

  • width (int) – the width of the input image.

  • p (float) – probability for applying an augmentation to a batch. This param controls the augmentation probabilities batch-wisely.

  • num_mix (int) – cut mix times. Default is 1.

  • beta (float or torch.Tensor, optional) – hyperparameter for generating cut size from beta distribution. Beta cannot be set to 0 after torch 1.8.0. If None, it will be set to 1.

  • cut_size ((float, float) or torch.Tensor, optional) – controlling the minimum and maximum cut ratio from [0, 1]. If None, it will be set to [0, 1], which means no restriction.

  • same_on_batch (bool) – apply the same transformation across the batch. This flag will not maintain permutation order. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False

Inputs:
  • Input image tensors, shape of \((B, C, H, W)\).

  • Raw labels, shape of \((B)\).

Returns

  • Adjusted image, shape of \((B, C, H, W)\).

  • Raw labels, permuted labels and lambdas for each mix, shape of \((B, num_mix, 3)\).

Return type

Tuple[torch.Tensor, torch.Tensor]

Note

This implementation would randomly cutmix images in a batch. Ideally, the larger batch size would be preferred.

Examples

>>> rng = torch.manual_seed(3)
>>> input = torch.rand(2, 1, 3, 3)
>>> input[0] = torch.ones((1, 3, 3))
>>> label = torch.tensor([0, 1])
>>> cutmix = RandomCutMix(3, 3)
>>> cutmix(input, label)
(tensor([[[[0.8879, 0.4510, 1.0000],
          [0.1498, 0.4015, 1.0000],
          [1.0000, 1.0000, 1.0000]]],
<BLANKLINE>
<BLANKLINE>
        [[[1.0000, 1.0000, 0.7995],
          [1.0000, 1.0000, 0.0542],
          [0.4594, 0.1756, 0.9492]]]]), tensor([[[0.0000, 1.0000, 0.4444],
         [1.0000, 0.0000, 0.4444]]]))
class RandomInvert(max_val: torch.Tensor = tensor(1.), return_transform: bool = False, same_on_batch: bool = False, p: float = 0.5)[source]

Invert the tensor images values randomly.

Parameters
  • max_val (torch.Tensor) – The expected maximum value in the input tensor. The shape has to according to the input tensor shape, or at least has to work with broadcasting. Default: 1.0.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • p (float) – probability of applying the transformation. Default value is 0.5.

Examples

>>> rng = torch.manual_seed(0)
>>> img = torch.rand(1, 1, 5, 5)
>>> inv = RandomInvert()
>>> inv(img)
tensor([[[[0.4963, 0.7682, 0.0885, 0.1320, 0.3074],
          [0.6341, 0.4901, 0.8964, 0.4556, 0.6323],
          [0.3489, 0.4017, 0.0223, 0.1689, 0.2939],
          [0.5185, 0.6977, 0.8000, 0.1610, 0.2823],
          [0.6816, 0.9152, 0.3971, 0.8742, 0.4194]]]])
class RandomChannelShuffle(return_transform: bool = False, same_on_batch: bool = False, p: float = 0.5)[source]

Shuffles the channels of a batch of multi-dimensional images.

Parameters
  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • p (float) – probability of applying the transformation. Default value is 0.5.

Examples

>>> rng = torch.manual_seed(0)
>>> img = torch.arange(1*2*2*2.).view(1,2,2,2)
>>> RandomChannelShuffle()(img)
tensor([[[[4., 5.],
          [6., 7.]],
<BLANKLINE>
         [[0., 1.],
          [2., 3.]]]])
class RandomGaussianNoise(mean: float = 0.0, std: float = 1.0, return_transform: bool = False, same_on_batch: bool = False, p: float = 0.5)[source]

Add gaussian noise to a batch of multi-dimensional images.

Parameters
  • mean (float) – The mean of the gaussian distribution. Default: 0.

  • std (float) – The standard deviation of the gaussian distribution. Default: 1.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • p (float) – probability of applying the transformation. Default value is 0.5.

Examples

>>> rng = torch.manual_seed(0)
>>> img = torch.ones(1, 1, 2, 2)
>>> RandomGaussianNoise(mean=0., std=1., p=1.)(img)
tensor([[[[ 2.5410,  0.7066],
          [-1.1788,  1.5684]]]])
apply_adjust_brightness(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Apply brightness adjustment.

Wrapper for adjust_brightness for Torchvision-like param settings.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘brightness_factor’]: Brightness adjust factor per element in the batch. 0 gives a black image, 1 does not modify the input image and 2 gives a white image, while any other number modify the brightness.

Returns

Adjusted image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_adjust_contrast(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Apply contrast adjustment.

Wrapper for adjust_contrast for Torchvision-like param settings.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘contrast_factor’]: Contrast adjust factor per element in the batch. 0 generates a compleatly black image, 1 does not modify the input image while any other non-negative number modify the brightness by this factor.

Returns

Adjusted image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_adjust_gamma(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Perform gamma correction on an image.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘gamma_factor’]: Non negative real number, same as γgammaγ in the equation. gamma larger than 1 make the shadows darker, while gamma smaller than 1 make dark regions lighter.

Returns

Adjusted image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_adjust_hue(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Apply hue adjustment.

Wrapper for adjust_hue for Torchvision-like param settings.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘hue_factor’]: How much to shift the hue channel. Should be in [-0.5, 0.5]. 0.5 and -0.5 give complete reversal of hue channel in HSV space in positive and negative direction respectively. 0 means no shift. Therefore, both -0.5 and 0.5 will give an image with complementary colors while 0 gives the original image.

Returns

Adjusted image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_adjust_saturation(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Apply saturation adjustment.

Wrapper for adjust_saturation for Torchvision-like param settings.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘saturation_factor’]: How much to adjust the saturation. 0 will give a black and white image, 1 will give the original image while 2 will enhance the saturation by a factor of 2.

Returns

Adjusted image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_affine(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Random affine transformation of the image keeping center invariant.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘angle’]: Degrees of rotation.

    • params[‘translations’]: Horizontal and vertical translations.

    • params[‘center’]: Rotation center.

    • params[‘scale’]: Scaling params.

    • params[‘sx’]: Shear param toward x-axis.

    • params[‘sy’]: Shear param toward y-axis.

  • flags (Dict[str, torch.Tensor]) –

    • params[‘resample’]: Integer tensor. NEAREST = 0, BILINEAR = 1.

    • params[‘padding_mode’]: Integer tensor, see SamplePadding enum.

    • params[‘align_corners’]: Boolean tensor.

Returns

The transfromed input with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_color_jitter(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Apply Color Jitter on a tensor image or a batch of tensor images with given random parameters.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘brightness_factor’]: The brightness factor.

    • params[‘contrast_factor’]: The contrast factor.

    • params[‘hue_factor’]: The hue factor.

    • params[‘saturation_factor’]: The saturation factor.

    • params[‘order’]: The order of applying color transforms. 0 is brightness, 1 is contrast, 2 is saturation, 4 is hue.

Returns

Color jitterred input with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_crop(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Apply cropping by src bounding box and dst bounding box.

Order: top-left, top-right, bottom-right and bottom-left. The coordinates must be in the x, y order.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘src’]: The applied cropping src matrix :math: (*, 4, 2).

    • params[‘dst’]: The applied cropping dst matrix :math: (*, 4, 2).

  • flags (Dict[str, torch.Tensor]) –

    • params[‘interpolation’]: Integer tensor. NEAREST = 0, BILINEAR = 1.

    • params[‘align_corners’]: Boolean tensor.

Returns

The cropped input.

Return type

torch.Tensor

apply_cutmix(input: torch.Tensor, labels: torch.Tensor, params: Dict[str, torch.Tensor]) → Tuple[torch.Tensor, torch.Tensor][source]

Apply cutmix to images in a batch.

CutMix augmentation strategy: patches are cut and pasted among training images where the ground truth labels are also mixed proportionally to the area of the patches.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • labels (torch.Tensor) – Label tensor with shape \((B,)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘mix_pairs’]: Mixup indexes with shape \((num_mixes, B)\).

    • params[‘crop_src’]: Lambda for the mixup strength \((num_mixes, B, 4, 2)\).

Returns

  • Adjusted image, shape of \((B, C, H, W)\).

  • Corresponding labels and lambdas for each mix, shape of \((num_mixes, B, 2)\).

Return type

Tuple[torch.Tensor, torch.Tensor]

Examples

>>> input = torch.stack([torch.zeros(1, 5, 5), torch.ones(1, 5, 5)], dim=0)
>>> labels = torch.tensor([0, 1])
>>> params = {'mix_pairs': torch.tensor([[1, 0]]), 'crop_src': torch.tensor([[[
...        [1., 1.],
...        [2., 1.],
...        [2., 2.],
...        [1., 2.]],
...       [[1., 1.],
...        [3., 1.],
...        [3., 2.],
...        [1., 2.]]]])}
>>> apply_cutmix(input, labels, params)
(tensor([[[[0., 0., 0., 0., 0.],
          [0., 1., 1., 0., 0.],
          [0., 1., 1., 0., 0.],
          [0., 0., 0., 0., 0.],
          [0., 0., 0., 0., 0.]]],
<BLANKLINE>
<BLANKLINE>
        [[[1., 1., 1., 1., 1.],
          [1., 0., 0., 0., 1.],
          [1., 0., 0., 0., 1.],
          [1., 1., 1., 1., 1.],
          [1., 1., 1., 1., 1.]]]]), tensor([[[0.0000, 1.0000, 0.1600],
         [1.0000, 0.0000, 0.2400]]]))
apply_equalize(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Equalize an image.

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

Returns

Adjusted image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_erase_rectangles(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Apply rectangle erase by params.

Generate a {0, 1} mask with drawed rectangle having parameters defined by params and size by input.size().

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘widths’]: widths tensor

    • params[‘heights’]: heights tensor

    • params[‘xs’]: x positions tensor

    • params[‘ys’]: y positions tensor

    • params[‘values’]: the value to fill in

Returns

Erased image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_grayscale(input: torch.Tensor) → torch.Tensor[source]

Apply Gray Scale on a tensor image or a batch of tensor images with given random parameters.

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

Returns

The grayscaled input with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_hflip(input: torch.Tensor) → torch.Tensor[source]

Apply Horizontally flip on a tensor image or a batch of tensor images with given random parameters.

Input should be a tensor of shape (H, W), (C, H, W) or a batch of tensors \((B, C, H, W)\).

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

Returns

The horizontally flipped input with shape \((*, C, H, W)\).

Return type

torch.Tensor

apply_mixup(input: torch.Tensor, labels: torch.Tensor, params: Dict[str, torch.Tensor]) → Tuple[torch.Tensor, torch.Tensor][source]

Apply mixup to images in a batch.

MixUp augmentation strategy: overlap images with different alpha values.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • labels (torch.Tensor) – Label tensor with shape \((B,)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘mixup_pairs’]: Mixup indexes.

    • params[‘mixup_lambdas’]: Lambda for the mixup strength.

Returns

  • Adjusted image, shape of \((B, C, H, W)\).

  • Raw labels, corresponding labels and lambdas for each mix, shape of \((B, 3)\).

Return type

Tuple[torch.Tensor, torch.Tensor]

Examples

>>> input = torch.stack([torch.eye(5).unsqueeze(dim=0), torch.ones(5, 5).unsqueeze(dim=0)])
>>> labels = torch.tensor([0, 1])
>>> params = dict(mixup_pairs=torch.tensor([1, 0]), mixup_lambdas=torch.tensor([0.5, 0.9]))
>>> out_img, out_label = apply_mixup(input, labels, params)
>>> out_img
tensor([[[[1.0000, 0.5000, 0.5000, 0.5000, 0.5000],
          [0.5000, 1.0000, 0.5000, 0.5000, 0.5000],
          [0.5000, 0.5000, 1.0000, 0.5000, 0.5000],
          [0.5000, 0.5000, 0.5000, 1.0000, 0.5000],
          [0.5000, 0.5000, 0.5000, 0.5000, 1.0000]]],
<BLANKLINE>
<BLANKLINE>
        [[[1.0000, 0.1000, 0.1000, 0.1000, 0.1000],
          [0.1000, 1.0000, 0.1000, 0.1000, 0.1000],
          [0.1000, 0.1000, 1.0000, 0.1000, 0.1000],
          [0.1000, 0.1000, 0.1000, 1.0000, 0.1000],
          [0.1000, 0.1000, 0.1000, 0.1000, 1.0000]]]])
>>> out_label
tensor([[0.0000, 1.0000, 0.5000],
        [1.0000, 0.0000, 0.9000]])
apply_motion_blur(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Perform motion blur on an image.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘ksize_factor’]: motion kernel width and height (odd and positive).

    • params[‘angle_factor’]: angle of the motion blur in degrees (anti-clockwise rotation).

    • params[‘direction_factor’]: forward/backward direction of the motion blur. Lower values towards -1.0 will point the motion blur towards the back (with angle provided via angle), while higher values towards 1.0 will point the motion blur forward. A value of 0.0 leads to a uniformly (but still angled) motion blur.

  • flags (Dict[str, torch.Tensor]) –

    • flags[‘border_type’]: the padding mode to be applied before convolving. CONSTANT = 0, REFLECT = 1, REPLICATE = 2, CIRCULAR = 3. Default: BorderType.CONSTANT.

Returns

Adjusted image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_perspective(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Perform perspective transform of the given torch.Tensor or batch of tensors.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘start_points’]: Tensor containing [top-left, top-right, bottom-right, bottom-left] of the original image with shape Bx4x2.

    • params[‘end_points’]: Tensor containing [top-left, top-right, bottom-right, bottom-left] of the transformed image with shape Bx4x2.

  • flags (Dict[str, torch.Tensor]) –

    • params[‘interpolation’]: Integer tensor. NEAREST = 0, BILINEAR = 1.

    • params[‘align_corners’]: Boolean tensor.

Returns

Perspectively transformed tensor.

Return type

torch.Tensor

apply_posterize(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Posterize an image.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘bits_factor’]: uint8 bits number ranged from 0 to 8.

Returns

Adjusted image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_rotation(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Rotate a tensor image or a batch of tensor images a random amount of degrees.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘degrees’]: degree to be applied.

  • flags (Dict[str, torch.Tensor]) –

    • params[‘interpolation’]: Integer tensor. NEAREST = 0, BILINEAR = 1.

    • params[‘align_corners’]: Boolean tensor.

Returns

The cropped input.

Return type

torch.Tensor

apply_sharpness(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Sharpen an image.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘sharpness_factor’]: Sharpness strength. Must be above 0.

Returns

Adjusted image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_solarize(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Solarize an image.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘thresholds_factor’]: thresholds ranged from 0 ~ 1.

    • params[‘additions_factor’]: additions to add on before solarizing.

Returns

Adjusted image with shape \((B, C, H, W)\).

Return type

torch.Tensor

apply_vflip(input: torch.Tensor) → torch.Tensor[source]

Apply vertically flip on a tensor image or a batch of tensor images with given random parameters.

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

Returns

Vertically flipped input with shape \((B, C, H, W)\).

Return type

torch.Tensor

compute_affine_transformation(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Compute the affine transformation matrix :math: (*, 3, 3).

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘angle’]: Degrees of rotation.

    • params[‘translations’]: Horizontal and vertical translations.

    • params[‘center’]: Rotation center.

    • params[‘scale’]: Scaling params.

    • params[‘sx’]: Shear param toward x-axis.

    • params[‘sy’]: Shear param toward y-axis.

Returns

The affine transformation matrix :math: (*, 3, 3).

Return type

torch.Tensor

compute_crop_transformation(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor])[source]

Compute the applied transformation matrix :math: (*, 3, 3).

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘src’]: The applied cropping src matrix :math: (*, 4, 2).

    • params[‘dst’]: The applied cropping dst matrix :math: (*, 4, 2).

Returns

The applied transformation matrix :math: (*, 3, 3)

Return type

torch.Tensor

compute_hflip_transformation(input: torch.Tensor) → torch.Tensor[source]

Compute the horizontal flip transformation matrix :math: (*, 3, 3).

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

Returns

The horizontal flip transformation matrix :math: (*, 3, 3)

Return type

torch.Tensor

compute_intensity_transformation(input: torch.Tensor)[source]

Compute the identity matrix :math: (*, 3, 3).

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

Returns

The applied matrix :math: (*, 3, 3).

Return type

torch.Tensor

compute_perspective_transformation(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Compute the perspective transformation matrix :math: (*, 3, 3).

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘start_points’]: Tensor containing [top-left, top-right, bottom-right, bottom-left] of the orignal image with shape Bx4x2.

    • params[‘end_points’]: Tensor containing [top-left, top-right, bottom-right, bottom-left] of the transformed image with shape Bx4x2.

Returns

The perspective transformation matrix :math: (*, 3, 3)

Return type

torch.Tensor

compute_rotate_tranformation(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Compute the rotation transformation matrix :math: (*, 3, 3).

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘degrees’]: degree to be applied.

Returns

The rotation transformation matrix :math: (*, 3, 3)

Return type

torch.Tensor

compute_vflip_transformation(input: torch.Tensor) → torch.Tensor[source]

Compute the vertical flip transformation matrix :math: (*, 3, 3).

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, H, W)\).

Returns

The vertical flip transformation matrix :math: (*, 3, 3)

Return type

torch.Tensor

Transforms3D

Set of operators to perform data augmentation on 3D volumetric tensors.

class RandomDepthicalFlip3D(return_transform: bool = False, same_on_batch: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Apply random flip along the depth axis of 3D volumes (5D tensor).

Input should be a tensor of shape \((C, D, H, W)\) or a batch of tensors \((*, C, D, H, W)\). If Input is a tuple it is assumed that the first element contains the aforementioned tensors and the second, the corresponding transformation matrix that has been applied to them. In this case the module will Depthically flip the tensors and concatenate the corresponding transformation matrix to the previous one. This is especially useful when using this functionality as part of an nn.Sequential module.

Parameters
  • p (float) – probability of the image being flipped. Default value is 0.5.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, D, H, W)\) or \((B, C, D, H, W)\), Optional: \((B, 4, 4)\)

  • Output: \((B, C, D, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 4, 4)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> x = torch.eye(3).repeat(3, 1, 1)
>>> seq = RandomDepthicalFlip3D(p=1.0, return_transform=True)
>>> seq(x)
(tensor([[[[[1., 0., 0.],
           [0., 1., 0.],
           [0., 0., 1.]],
<BLANKLINE>
          [[1., 0., 0.],
           [0., 1., 0.],
           [0., 0., 1.]],
<BLANKLINE>
          [[1., 0., 0.],
           [0., 1., 0.],
           [0., 0., 1.]]]]]), tensor([[[ 1.,  0.,  0.,  0.],
         [ 0.,  1.,  0.,  0.],
         [ 0.,  0., -1.,  2.],
         [ 0.,  0.,  0.,  1.]]]))
class RandomHorizontalFlip3D(return_transform: bool = False, same_on_batch: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Apply random horizontal flip to 3D volumes (5D tensor).

Parameters
  • p (float) – probability of the image being flipped. Default value is 0.5.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, D, H, W)\) or \((B, C, D, H, W)\), Optional: \((B, 4, 4)\)

  • Output: \((B, C, D, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 4, 4)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> x = torch.eye(3).repeat(3, 1, 1)
>>> seq = RandomHorizontalFlip3D(p=1.0, return_transform=True)
>>> seq(x)
(tensor([[[[[0., 0., 1.],
           [0., 1., 0.],
           [1., 0., 0.]],
<BLANKLINE>
          [[0., 0., 1.],
           [0., 1., 0.],
           [1., 0., 0.]],
<BLANKLINE>
          [[0., 0., 1.],
           [0., 1., 0.],
           [1., 0., 0.]]]]]), tensor([[[-1.,  0.,  0.,  2.],
         [ 0.,  1.,  0.,  0.],
         [ 0.,  0.,  1.,  0.],
         [ 0.,  0.,  0.,  1.]]]))
class RandomVerticalFlip3D(return_transform: bool = False, same_on_batch: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Apply random vertical flip to 3D volumes (5D tensor).

Input should be a tensor of shape \((C, D, H, W)\) or a batch of tensors \((*, C, D, H, W)\). If Input is a tuple it is assumed that the first element contains the aforementioned tensors and the second, the corresponding transformation matrix that has been applied to them. In this case the module will Vertically flip the tensors and concatenate the corresponding transformation matrix to the previous one. This is especially useful when using this functionality as part of an nn.Sequential module.

Parameters
  • p (float) – probability of the image being flipped. Default value is 0.5.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, D, H, W)\) or \((B, C, D, H, W)\), Optional: \((B, 4, 4)\)

  • Output: \((B, C, D, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 4, 4)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> x = torch.eye(3).repeat(3, 1, 1)
>>> seq = RandomVerticalFlip3D(p=1.0, return_transform=True)
>>> seq(x)
(tensor([[[[[0., 0., 1.],
           [0., 1., 0.],
           [1., 0., 0.]],
<BLANKLINE>
          [[0., 0., 1.],
           [0., 1., 0.],
           [1., 0., 0.]],
<BLANKLINE>
          [[0., 0., 1.],
           [0., 1., 0.],
           [1., 0., 0.]]]]]), tensor([[[ 1.,  0.,  0.,  0.],
         [ 0., -1.,  0.,  2.],
         [ 0.,  0.,  1.,  0.],
         [ 0.,  0.,  0.,  1.]]]))
class RandomRotation3D(degrees: Union[torch.Tensor, float, Tuple[float, float, float], Tuple[Tuple[float, float], Tuple[float, float], Tuple[float, float]]], resample: Union[str, int, <unknown>.Resample] = 'BILINEAR', return_transform: bool = False, same_on_batch: bool = False, align_corners: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Apply random rotations to 3D volumes (5D tensor).

Input should be a tensor of shape (C, D, H, W) or a batch of tensors \((B, C, D, H, W)\). If Input is a tuple it is assumed that the first element contains the aforementioned tensors and the second, the corresponding transformation matrix that has been applied to them. In this case the module will rotate the tensors and concatenate the corresponding transformation matrix to the previous one. This is especially useful when using this functionality as part of an nn.Sequential module.

Parameters
  • degrees (float or tuple or list) – Range of degrees to select from. If degrees is a number, then yaw, pitch, roll will be generated from the range of (-degrees, +degrees). If degrees is a tuple of (min, max), then yaw, pitch, roll will be generated from the range of (min, max). If degrees is a list of floats [a, b, c], then yaw, pitch, roll will be generated from (-a, a), (-b, b) and (-c, c). If degrees is a list of tuple ((a, b), (m, n), (x, y)), then yaw, pitch, roll will be generated from (a, b), (m, n) and (x, y). Set to 0 to deactivate rotations.

  • resample (int, str or kornia.Resample) – Default: Resample.BILINEAR

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • align_corners (bool) – interpolation flag. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, D, H, W)\) or \((B, C, D, H, W)\), Optional: \((B, 4, 4)\)

  • Output: \((B, C, D, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 4, 4)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.rand(1, 1, 3, 3, 3)
>>> aug = RandomRotation3D((15., 20., 20.), p=1.0, return_transform=True)
>>> aug(input)
(tensor([[[[[0.3819, 0.4886, 0.2111],
           [0.1196, 0.3833, 0.4722],
           [0.3432, 0.5951, 0.4223]],
<BLANKLINE>
          [[0.5553, 0.4374, 0.2780],
           [0.2423, 0.1689, 0.4009],
           [0.4516, 0.6376, 0.7327]],
<BLANKLINE>
          [[0.1605, 0.3112, 0.3673],
           [0.4931, 0.4620, 0.5700],
           [0.3505, 0.4685, 0.8092]]]]]), tensor([[[ 0.9722,  0.1131, -0.2049,  0.1196],
         [-0.0603,  0.9669,  0.2478, -0.1545],
         [ 0.2262, -0.2286,  0.9469,  0.0556],
         [ 0.0000,  0.0000,  0.0000,  1.0000]]]))
class RandomAffine3D(degrees: Union[torch.Tensor, float, Tuple[float, float], Tuple[float, float, float], Tuple[Tuple[float, float], Tuple[float, float], Tuple[float, float]]], translate: Union[torch.Tensor, Tuple[float, float, float], None] = None, scale: Union[torch.Tensor, Tuple[float, float], Tuple[Tuple[float, float], Tuple[float, float], Tuple[float, float]], None] = None, shears: Union[torch.Tensor, float, Tuple[float, float], Tuple[float, float, float, float, float, float], Tuple[Tuple[float, float], Tuple[float, float], Tuple[float, float], Tuple[float, float], Tuple[float, float], Tuple[float, float]]] = None, resample: Union[str, int, <unknown>.Resample] = 'BILINEAR', return_transform: bool = False, same_on_batch: bool = False, align_corners: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Apply affine transformation 3D volumes (5D tensor).

The transformation is computed so that the center is kept invariant.

Parameters
  • degrees (float or tuple or list) – Range of yaw (x-axis), pitch (y-axis), roll (z-axis) to select from. If degrees is a number, then yaw, pitch, roll will be generated from the range of (-degrees, +degrees). If degrees is a tuple of (min, max), then yaw, pitch, roll will be generated from the range of (min, max). If degrees is a list of floats [a, b, c], then yaw, pitch, roll will be generated from (-a, a), (-b, b) and (-c, c). If degrees is a list of tuple ((a, b), (m, n), (x, y)), then yaw, pitch, roll will be generated from (a, b), (m, n) and (x, y). Set to 0 to deactivate rotations.

  • translate (tuple, optional) – tuple of maximum absolute fraction for horizontal, vertical and

  • translations (depthical) – horizontal shift will be randomly sampled in the range -img_width * a < dx < img_width * a vertical shift will be randomly sampled in the range -img_height * b < dy < img_height * b. depthical shift will be randomly sampled in the range -img_depth * c < dz < img_depth * c. Will not translate by default.

  • scale (tuple, optional) – scaling factor interval. If (a, b) represents isotropic scaling, the scale is randomly sampled from the range a <= scale <= b. If ((a, b), (c, d), (e, f)), the scale is randomly sampled from the range a <= scale_x <= b, c <= scale_y <= d, e <= scale_z <= f. Will keep original scale by default.

  • shear (sequence or float, optional) – Range of degrees to select from. If shear is a number, a shear to the 6 facets in the range (-shear, +shear) will be applied. If shear is a tuple of 2 values, a shear to the 6 facets in the range (shear[0], shear[1]) will be applied. If shear is a tuple of 6 values, a shear to the i-th facet in the range (-shear[i], shear[i]) will be applied. If shear is a tuple of 6 tuples, a shear to the i-th facet in the range (-shear[i, 0], shear[i, 1]) will be applied.

  • resample (int, str or kornia.Resample) – Default: Resample.BILINEAR.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each. Default: False.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • align_corners (bool) – interpolation flag. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, D, H, W)\) or \((B, C, D, H, W)\), Optional: \((B, 4, 4)\)

  • Output: \((B, C, D, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 4, 4)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.rand(1, 1, 3, 3, 3)
>>> aug = RandomAffine3D((15., 20., 20.), p=1., return_transform=True)
>>> aug(input)
(tensor([[[[[0.4503, 0.4763, 0.1680],
           [0.2029, 0.4267, 0.3515],
           [0.3195, 0.5436, 0.3706]],
<BLANKLINE>
          [[0.5255, 0.3508, 0.4858],
           [0.0795, 0.1689, 0.4220],
           [0.5306, 0.7234, 0.6879]],
<BLANKLINE>
          [[0.2971, 0.2746, 0.3471],
           [0.4924, 0.4960, 0.6460],
           [0.3187, 0.4556, 0.7596]]]]]), tensor([[[ 0.9722, -0.0603,  0.2262, -0.1381],
         [ 0.1131,  0.9669, -0.2286,  0.1486],
         [-0.2049,  0.2478,  0.9469,  0.0102],
         [ 0.0000,  0.0000,  0.0000,  1.0000]]]))
class RandomCrop3D(size: Tuple[int, int, int], padding: Union[int, Tuple[int, int, int], Tuple[int, int, int, int, int, int], None] = None, pad_if_needed: Optional[bool] = False, fill: int = 0, padding_mode: str = 'constant', resample: Union[str, int, <unknown>.Resample] = 'BILINEAR', return_transform: bool = False, same_on_batch: bool = False, align_corners: bool = True, p: float = 1.0, keepdim: bool = False)[source]

Apply random crop on 3D volumes (5D tensor).

Crops random sub-volumes on a given size.

Parameters
  • p (float) – probability of applying the transformation for the whole batch. Default value is 1.0.

  • size (Tuple[int, int, int]) – Desired output size (out_d, out_h, out_w) of the crop. Must be Tuple[int, int, int], then out_d = size[0], out_h = size[1], out_w = size[2].

  • padding (int or sequence, optional) – Optional padding on each border of the image. Default is None, i.e no padding. If a sequence of length 6 is provided, it is used to pad left, top, right, bottom, front, back borders respectively. If a sequence of length 3 is provided, it is used to pad left/right, top/bottom, front/back borders, respectively.

  • pad_if_needed (boolean) – It will pad the image if smaller than the desired size to avoid raising an exception. Since cropping is done after padding, the padding seems to be done at a random offset.

  • fill – Pixel fill value for constant fill. Default is 0. If a tuple of length 3, it is used to fill R, G, B channels respectively. This value is only used when the padding_mode is constant.

  • padding_mode – Type of padding. Should be: constant, edge, reflect or symmetric. Default is constant.

  • resample (int, str or kornia.Resample) – Default: Resample.BILINEAR

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • align_corners (bool) – interpolation flag. Default: True.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, D, H, W)\) or \((B, C, D, H, W)\), Optional: \((B, 4, 4)\)

  • Output: \((B, C, , out_d, out_h, out_w)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 4, 4)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> inputs = torch.randn(1, 1, 3, 3, 3)
>>> aug = RandomCrop3D((2, 2, 2), p=1.)
>>> aug(inputs)
tensor([[[[[-1.1258, -1.1524],
           [-0.4339,  0.8487]],
<BLANKLINE>
          [[-1.2633,  0.3500],
           [ 0.1665,  0.8744]]]]])
class CenterCrop3D(size: Union[int, Tuple[int, int, int]], align_corners: bool = True, resample: Union[str, int, <unknown>.Resample] = 'BILINEAR', return_transform: bool = False, p: float = 1.0, keepdim: bool = False)[source]

Apply center crop on 3D volumes (5D tensor).

Parameters
  • p (float) – probability of applying the transformation for the whole batch. Default value is 1.

  • size (Tuple[int, int, int] or int) – Desired output size (out_d, out_h, out_w) of the crop. If integer, out_d = out_h = out_w = size. If Tuple[int, int, int], out_d = size[0], out_h = size[1], out_w = size[2].

  • resample (int, str or kornia.Resample) – Default: Resample.BILINEAR

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • align_corners (bool) – interpolation flag. Default: True.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, D, H, W)\) or \((B, C, D, H, W)\), Optional: \((B, 4, 4)\)

  • Output: \((B, C, out_d, out_h, out_w)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 4, 4)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> inputs = torch.randn(1, 1, 2, 4, 6)
>>> inputs
tensor([[[[[-1.1258, -1.1524, -0.2506, -0.4339,  0.8487,  0.6920],
           [-0.3160, -2.1152,  0.3223, -1.2633,  0.3500,  0.3081],
           [ 0.1198,  1.2377,  1.1168, -0.2473, -1.3527, -1.6959],
           [ 0.5667,  0.7935,  0.5988, -1.5551, -0.3414,  1.8530]],
<BLANKLINE>
          [[ 0.7502, -0.5855, -0.1734,  0.1835,  1.3894,  1.5863],
           [ 0.9463, -0.8437, -0.6136,  0.0316, -0.4927,  0.2484],
           [ 0.4397,  0.1124,  0.6408,  0.4412, -0.1023,  0.7924],
           [-0.2897,  0.0525,  0.5229,  2.3022, -1.4689, -1.5867]]]]])
>>> aug = CenterCrop3D(2, p=1.)
>>> aug(inputs)
tensor([[[[[ 0.3223, -1.2633],
           [ 1.1168, -0.2473]],
<BLANKLINE>
          [[-0.6136,  0.0316],
           [ 0.6408,  0.4412]]]]])
class RandomMotionBlur3D(kernel_size: Union[int, Tuple[int, int]], angle: Union[torch.Tensor, float, Tuple[float, float, float], Tuple[Tuple[float, float], Tuple[float, float], Tuple[float, float]]], direction: Union[torch.Tensor, float, Tuple[float, float]], border_type: Union[int, str, <unknown>.BorderType] = 'CONSTANT', resample: Union[str, int, <unknown>.Resample] = 'NEAREST', return_transform: bool = False, same_on_batch: bool = False, p: float = 0.5, keepdim: bool = False)[source]

Apply random motion blur on 3D volumes (5D tensor).

Parameters
  • p (float) – probability of applying the transformation. Default value is 0.5.

  • kernel_size (int or Tuple[int, int]) – motion kernel size (odd and positive). If int, the kernel will have a fixed size. If Tuple[int, int], it will randomly generate the value from the range batch-wisely.

  • angle (float or tuple or list) – Range of degrees to select from. If angle is a number, then yaw, pitch, roll will be generated from the range of (-angle, +angle). If angle is a tuple of (min, max), then yaw, pitch, roll will be generated from the range of (min, max). If angle is a list of floats [a, b, c], then yaw, pitch, roll will be generated from (-a, a), (-b, b) and (-c, c). If angle is a list of tuple ((a, b), (m, n), (x, y)), then yaw, pitch, roll will be generated from (a, b), (m, n) and (x, y). Set to 0 to deactivate rotations.

  • direction (float or Tuple[float, float]) – forward/backward direction of the motion blur. Lower values towards -1.0 will point the motion blur towards the back (with angle provided via angle), while higher values towards 1.0 will point the motion blur forward. A value of 0.0 leads to a uniformly (but still angled) motion blur. If float, it will generate the value from (-direction, direction). If Tuple[int, int], it will randomly generate the value from the range.

  • border_type (int, str or kornia.BorderType) – the padding mode to be applied before convolving. CONSTANT = 0, REFLECT = 1, REPLICATE = 2, CIRCULAR = 3. Default: BorderType.CONSTANT.

  • resample (int, str or kornia.Resample) – resample mode from “nearest” (0) or “bilinear” (1). Default: Resample.NEAREST.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, D, H, W)\) or \((B, C, D, H, W)\), Optional: \((B, 4, 4)\)

  • Output: \((B, C, D, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 4, 4)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.rand(1, 1, 3, 5, 5)
>>> motion_blur = RandomMotionBlur3D(3, 35., 0.5, p=1.)
>>> motion_blur(input)
tensor([[[[[0.1654, 0.4772, 0.2004, 0.3566, 0.2613],
           [0.4557, 0.3131, 0.4809, 0.2574, 0.2696],
           [0.2721, 0.5998, 0.3956, 0.5363, 0.1541],
           [0.3006, 0.4773, 0.6395, 0.2856, 0.3989],
           [0.4491, 0.5595, 0.1836, 0.3811, 0.1398]],
<BLANKLINE>
          [[0.1843, 0.4240, 0.3370, 0.1231, 0.2186],
           [0.4047, 0.3332, 0.1901, 0.5329, 0.3023],
           [0.3070, 0.3088, 0.4807, 0.4928, 0.2590],
           [0.2416, 0.4614, 0.7091, 0.5237, 0.1433],
           [0.1582, 0.4577, 0.2749, 0.1369, 0.1607]],
<BLANKLINE>
          [[0.2733, 0.4040, 0.4396, 0.2284, 0.3319],
           [0.3856, 0.6730, 0.4624, 0.3878, 0.3076],
           [0.4307, 0.4217, 0.2977, 0.5086, 0.5406],
           [0.3686, 0.2778, 0.5228, 0.7592, 0.6455],
           [0.2033, 0.3014, 0.4898, 0.6164, 0.3117]]]]])
class RandomEqualize3D(p: float = 0.5, return_transform: bool = False, same_on_batch: bool = False, keepdim: bool = False)[source]

Apply random equalization to 3D volumes (5D tensor).

Parameters
  • p (float) – probability of the image being equalized. Default value is 0.5.

  • return_transform (bool) – if True return the matrix describing the transformation applied to each input tensor. If False and the input is a tuple the applied transformation wont be concatenated.

  • same_on_batch (bool) – apply the same transformation across the batch. Default: False.

  • keepdim (bool) – whether to keep the output shape the same as input (True) or broadcast it to the batch form (False). Default: False.

Shape:
  • Input: \((C, D, H, W)\) or \((B, C, D, H, W)\), Optional: \((B, 4, 4)\)

  • Output: \((B, C, D, H, W)\)

Note

Input tensor must be float and normalized into [0, 1] for the best differentiability support. Additionally, this function accepts another transformation tensor (\((B, 4, 4)\)), then the applied transformation will be merged int to the input transformation tensor and returned.

Examples

>>> rng = torch.manual_seed(0)
>>> input = torch.rand(1, 1, 3, 3, 3)
>>> aug = RandomEqualize3D(p=1.0)
>>> aug(input)
tensor([[[[[0.4963, 0.7682, 0.0885],
           [0.1320, 0.3074, 0.6341],
           [0.4901, 0.8964, 0.4556]],
<BLANKLINE>
          [[0.6323, 0.3489, 0.4017],
           [0.0223, 0.1689, 0.2939],
           [0.5185, 0.6977, 0.8000]],
<BLANKLINE>
          [[0.1610, 0.2823, 0.6816],
           [0.9152, 0.3971, 0.8742],
           [0.4194, 0.5529, 0.9527]]]]])
apply_affine3d(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Random affine transformation of the image keeping center invariant.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘angles’]: Degrees of rotation with the shape of :math: (*, 3) for yaw, pitch, roll.

    • params[‘translations’]: Horizontal, vertical and depthical translations (dx,dy,dz).

    • params[‘center’]: Rotation center (x,y,z).

    • params[‘scale’]: Isotropic scaling params.

    • params[‘sxy’]: Shear param toward x-y-axis.

    • params[‘sxz’]: Shear param toward x-z-axis.

    • params[‘syx’]: Shear param toward y-x-axis.

    • params[‘syz’]: Shear param toward y-z-axis.

    • params[‘szx’]: Shear param toward z-x-axis.

    • params[‘szy’]: Shear param toward z-y-axis.

  • flags (Dict[str, torch.Tensor]) –

    • params[‘resample’]: Integer tensor. NEAREST = 0, BILINEAR = 1.

    • params[‘align_corners’]: Boolean tensor.

Returns

Affine transfromed input with shape \((*, C, D, H, W)\).

Return type

torch.Tensor

apply_crop3d(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Apply cropping by src bounding box and dst bounding box.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘src’]: The applied cropping src matrix :math: (*, 8, 3).

    • params[‘dst’]: The applied cropping dst matrix :math: (*, 8, 3).

  • flags (Dict[str, torch.Tensor]) –

    • params[‘interpolation’]: Integer tensor. NEAREST = 0, BILINEAR = 1.

    • params[‘align_corners’]: Boolean tensor.

Returns

The cropped input.

Return type

torch.Tensor

Note

BBox order: front-top-left, front-top-right, front-bottom-right, front-bottom-left, back-top-left, back-top-right, back-bottom-right, back-bottom-left. The coordinates must be in x, y, z order.

apply_dflip3d(input: torch.Tensor) → torch.Tensor[source]

Apply depthical flip on a 3D tensor volume or a batch of tensors volumes with given random parameters.

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

Returns

Depthical flipped input with shape \((*, C, D, H, W)\).

Return type

torch.Tensor

apply_equalize3d(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Equalize a tensor volume or a batch of tensors volumes with given random parameters.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

  • params (Dict[str, torch.Tensor]) – shall be empty.

Returns

Equalized input with shape \((*, C, D, H, W)\).

Return type

torch.Tensor

apply_hflip3d(input: torch.Tensor) → torch.Tensor[source]

Apply horizontal flip on a 3D tensor volume or a batch of tensors volumes with given random parameters.

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

Returns

Horizontal flipped input with shape \((*, C, D, H, W)\).

Return type

torch.Tensor

apply_motion_blur3d(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Perform motion blur on an image.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘ksize_factor’]: motion kernel width and height (odd and positive).

    • params[‘angle_factor’]: yaw, pitch and roll range of the motion blur in degrees \((B, 3)\).

    • params[‘direction_factor’]: forward/backward direction of the motion blur. Lower values towards -1.0 will point the motion blur towards the back (with angle provided via angle), while higher values towards 1.0 will point the motion blur forward. A value of 0.0 leads to a uniformly (but still angled) motion blur.

  • flags (Dict[str, torch.Tensor]) –

    • flags[‘border_type’]: the padding mode to be applied before convolving. CONSTANT = 0, REFLECT = 1, REPLICATE = 2, CIRCULAR = 3. Default: BorderType.CONSTANT.

Returns

adjusted image tensor with shape \((*, C, D, H, W)\).

Return type

torch.Tensor

apply_perspective3d(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Perform perspective transform of the given torch.Tensor or batch of tensors.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘start_points’]: Tensor containing [top-left, top-right, bottom-right, bottom-left] of the original image with shape Bx8x3.

    • params[‘end_points’]: Tensor containing [top-left, top-right, bottom-right, bottom-left] of the transformed image with shape Bx8x3.

  • flags (Dict[str, torch.Tensor]) –

    • params[‘interpolation’]: Integer tensor. NEAREST = 0, BILINEAR = 1.

    • params[‘align_corners’]: Boolean tensor.

Returns

Perspectively transformed tensor with shape \((*, C, D, H, W)\).

Return type

torch.Tensor

apply_rotation3d(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Rotate a tensor image or a batch of tensor images a random amount of degrees.

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘degrees’]: degree to be applied.

  • flags (Dict[str, torch.Tensor]) –

    • params[‘resample’]: Integer tensor. NEAREST = 0, BILINEAR = 1.

    • params[‘align_corners’]: Boolean tensor.

Returns

The cropped input.

Return type

torch.Tensor

apply_vflip3d(input: torch.Tensor) → torch.Tensor[source]

Apply vertical flip on a 3D tensor volume or a batch of tensors volumes with given random parameters.

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

Returns

Vertical flipped input with shape \((*, C, D, H, W)\).

Return type

torch.Tensor

compute_affine_transformation3d(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Compute the affine transformation matrix :math: (*, 4, 4).

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘angles’]: Degrees of rotation with the shape of :math: (*, 3) for yaw, pitch, roll.

    • params[‘translations’]: Horizontal, vertical and depthical translations (dx,dy,dz).

    • params[‘center’]: Rotation center (x,y,z).

    • params[‘scale’]: Isotropic scaling params.

    • params[‘sxy’]: Shear param toward x-y-axis.

    • params[‘sxz’]: Shear param toward x-z-axis.

    • params[‘syx’]: Shear param toward y-x-axis.

    • params[‘syz’]: Shear param toward y-z-axis.

    • params[‘szx’]: Shear param toward z-x-axis.

    • params[‘szy’]: Shear param toward z-y-axis.

Returns

The affine transformation matrix :math: (*, 4, 4).

Return type

torch.Tensor

compute_crop_transformation3d(input: torch.Tensor, params: Dict[str, torch.Tensor], flags: Dict[str, torch.Tensor]) → torch.Tensor[source]

Compute the cropping transformation matrix :math: (*, 4, 4).

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘src’]: The applied cropping src matrix :math: (*, 8, 3).

    • params[‘dst’]: The applied cropping dst matrix :math: (*, 8, 3).

Returns

The cropping transformation matrix :math: (*, 4, 4).

Return type

torch.Tensor

compute_dflip_transformation3d(input: torch.Tensor) → torch.Tensor[source]

Compute the depthical flip transformation matrix :math: (*, 4, 4).

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

Returns

Depthical flip transformation matrix :math: (*, 4, 4).

Return type

torch.Tensor

compute_hflip_transformation3d(input: torch.Tensor) → torch.Tensor[source]

Compute the horizontal flip transformation matrix :math: (*, 4, 4).

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

Returns

Horizontal flip transformation matrix :math: (*, 4, 4).

Return type

torch.Tensor

compute_intensity_transformation3d(input: torch.Tensor)[source]

Compute the identity matrix :math: (*, 4, 4).

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

Returns

Identity matrix :math: (*, 4, 4).

Return type

torch.Tensor

compute_perspective_transformation3d(input: torch.Tensor, params: Dict[str, torch.Tensor]) → torch.Tensor[source]

Compute the perspective transformation matrix :math: (*, 4, 4).

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘start_points’]: Tensor containing [top-left, top-right, bottom-right, bottom-left] of the orignal image with shape Bx8x3.

    • params[‘end_points’]: Tensor containing [top-left, top-right, bottom-right, bottom-left] of the transformed image with shape Bx8x3.

Returns

The perspective transformation matrix :math: (*, 4, 4)

Return type

torch.Tensor

compute_rotate_tranformation3d(input: torch.Tensor, params: Dict[str, torch.Tensor])[source]

Compute the rotation transformation matrix :math: (*, 4, 4).

Parameters
  • input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

  • params (Dict[str, torch.Tensor]) –

    • params[‘yaw’]: degree to be applied.

    • params[‘pitch’]: degree to be applied.

    • params[‘roll’]: degree to be applied.

Returns

The rotation transformation matrix :math: (*, 4, 4).

Return type

torch.Tensor

compute_vflip_transformation3d(input: torch.Tensor) → torch.Tensor[source]

Compute the veritical flip transformation matrix :math: (*, 4, 4).

Parameters

input (torch.Tensor) – Tensor to be transformed with shape \((*, C, D, H, W)\).

Returns

The vertical flip transformation matrix :math: (*, 4, 4).

Return type

torch.Tensor

Normalizations

Normalization operations are shape-agnostic for both 2D and 3D tensors.

class Denormalize(mean: torch.Tensor, std: torch.Tensor, return_transform: bool = False, p: float = 1.0, keepdim: bool = False)[source]

Denormalize tensor images with mean and standard deviation.

\[\text{input[channel] = (input[channel] * mean[channel]) + std[channel]}\]

Where mean is \((M_1, ..., M_n)\) and std \((S_1, ..., S_n)\) for n channels,

Parameters
Returns

Denormalised tensor with same size as input \((*, C, H, W)\).

Return type

torch.Tensor

Examples

>>> norm = Denormalize(mean=torch.zeros(1, 4), std=torch.ones(1, 4))
>>> x = torch.rand(1, 4, 3, 3)
>>> out = norm(x)
>>> out.shape
torch.Size([1, 4, 3, 3])
class Normalize(mean: torch.Tensor, std: torch.Tensor, return_transform: bool = False, p: float = 1.0, keepdim: bool = False)[source]

Normalize tensor images with mean and standard deviation.

\[\text{input[channel] = (input[channel] - mean[channel]) / std[channel]}\]

Where mean is \((M_1, ..., M_n)\) and std \((S_1, ..., S_n)\) for n channels,

Parameters
Returns

Normalised tensor with same size as input \((*, C, H, W)\).

Return type

torch.Tensor

Examples

>>> norm = Normalize(mean=torch.zeros(1, 4), std=torch.ones(1, 4))
>>> x = torch.rand(1, 4, 3, 3)
>>> out = norm(x)
>>> out.shape
torch.Size([1, 4, 3, 3])