Struct Volume 

struct Volume<'a> {
    owned: Option<Vec<f64>>,
    view: &'a [f64],
    dims: (usize, usize, usize),
    affine: [f64; 16],
}

One pyramid level: either a borrowed view of the caller’s data (level 0) or a decimated copy.

Fields

owned: Option<Vec<f64>>

view: &'a [f64]

dims: (usize, usize, usize)

affine: [f64; 16]

Implementations

impl<'a> Volume<'a>

fn borrowed( data: &'a [f64], dims: (usize, usize, usize), affine: [f64; 16], ) -> Self

fn data(&self) -> &[f64]

fn halved(&self) -> Volume<'static>

Halve every axis: a 5-tap binomial blur per axis, then keep the even samples.

The blur is the anti-aliasing the decimation needs; the binomial [1 4 6 4 1]/16 kernel is the usual pyramid choice and needs no sigma to tune (the crate’s box-filter Gaussian collapses to a no-op at the σ≈1 this calls for). Keeping the even samples means coarse voxel i sits exactly on fine voxel 2i, so the level’s affine is the fine affine with its three direction columns doubled and its translation untouched — exact, no half-voxel offset to get wrong.