Fast joint bilateral using a high-dimensional lattice (splat/blur/slice)

High-dimensional bilateral filtering using a permutohedral lattice backend. Supports optional spatial guide and additional per-voxel guides.

Usage

fast_bilateral_lattice3d(
  vol,
  sigma_sp = 2.5,
  sigma_r = 1,
  guide = NULL,
  guides = NULL,
  blur_iters = 2L,
  mask = NULL
)

vol: 3D volume array or `NeuroVol`.
sigma_sp: Spatial sigma (voxels).
sigma_r: Range sigma(s) for guide intensity dimensions. Scalar or vector matching `guide` + `guides` count. Has an effect only when a guide (or guides) is provided; otherwise the filter is purely spatial and `sigma_r` is ignored.
guide: Optional 3D spatial guide.
guides: Optional list of additional 3D guides (e.g., probabilities).
blur_iters: Integer number of lattice blur iterations.
mask: Optional 3D logical/0-1 mask.

Smoothed 3D volume, wrapped like `vol` when possible.