Spatial Distortions

Space distortions.

class nerfstudio.field_components.spatial_distortions.SceneContraction(order: Optional[Union[float, int]] = None)

Bases: SpatialDistortion

Contract unbounded space using the contraction was proposed in MipNeRF-360. We use the following contraction equation:

$$\begin{array}{r}f(x)=\{\begin{array}{ll}x& ||x||\le 1\\ (2-\frac{1}{||x||})(\frac{x}{||x||})& ||x||>1\end{array}\end{array}$$

If the order is not specified, we use the Frobenius norm, this will contract the space to a sphere of radius 2. If the order is L_inf (order=float(“inf”)), we will contract the space to a cube of side length 4. If using voxel based encodings such as the Hash encoder, we recommend using the L_inf norm.

Parameters:

order – Order of the norm. Default to the Frobenius norm. Must be set to None for Gaussians.

forward(positions)

Parameters:

positions – Sample to distort

Returns:

distorted sample

Return type:

Union

class nerfstudio.field_components.spatial_distortions.SpatialDistortion(*args, **kwargs)

Bases: Module

Apply spatial distortions

abstract forward(positions: Union[Float[Tensor, '*bs 3'], Gaussians]) → Union[Float[Tensor, '*bs 3'], Gaussians]

Parameters:

positions – Sample to distort

Returns:

distorted sample

Return type:

Union