Struct Kern 

pub struct Kern {
    pub typ: u32,
    pub halo: i32,
    pub n: i32,
    pub w: [i16; 256],
    pub h: [i32; 8],
}

a separable 1-D kernel (KERN)

Fields

typ: u32

halo: i32

n: i32

w: [i16; 256]

h: [i32; 8]

Implementations

impl Kern

pub fn copy() -> Kern

the identity

pub fn boxk(h: i32) -> Kern

one box of width 2h + 1 (h <= 0: identity) [fxc_kern_box]

pub fn gauss(var12: i32) -> Kern

Gaussian with 12 sigma^2 = var12 (<= 0: identity) [fxc_kern_gauss] FIR (var12 <= 432): h = ceil(sqrt(0.75 var12)) (1..18), g_i = exp(-6 i^2 / var12), sum = g_0 + 2 g_1 + …, q_i = trunc(g_i (16384 / sum) + 0.5), the centre absorbs 16384 - (q_0 + 2 sum q_i). Boxes: wl = largest odd w with 3 w^2 <= var12 + 3, m = (2 num + den) / (2 den) (num = 3 wl^2 + 12 wl + 9 - var12, den = 4 wl + 4, m <= 3): m boxes of width wl, then 3 - m of wl + 2.

Trait Implementations

impl Clone for Kern

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.