Struct rustfft::algorithm::MixedRadix

pub struct MixedRadix<T> { /* fields omitted */ }

Implementation of the Mixed-Radix FFT algorithm

This algorithm factors a size n FFT into n1 * n2, computes several inner FFTs of size n1 and n2, then combines the results to get the final answer

// Computes a forward FFT of size 1200, using the Mixed-Radix Algorithm
use rustfft::algorithm::MixedRadix;
use rustfft::{Fft, FftPlanner};
use rustfft::num_complex::Complex;

let mut buffer = vec![Complex{ re: 0.0f32, im: 0.0f32 }; 1200];

// we need to find an n1 and n2 such that n1 * n2 == 1200
// n1 = 30 and n2 = 40 satisfies this
let mut planner = FftPlanner::new();
let inner_fft_n1 = planner.plan_fft_forward(30);
let inner_fft_n2 = planner.plan_fft_forward(40);

// the mixed radix FFT length will be inner_fft_n1.len() * inner_fft_n2.len() = 1200
let fft = MixedRadix::new(inner_fft_n1, inner_fft_n2);
fft.process(&mut buffer);

Implementations

impl<T: FftNum> MixedRadix<T>

pub fn new(width_fft: Arc<dyn Fft<T>>, height_fft: Arc<dyn Fft<T>>) -> Self

Creates a FFT instance which will process inputs/outputs of size width_fft.len() * height_fft.len()

Trait Implementations

impl<T: FftNum> Direction for MixedRadix<T>

pub fn fft_direction(&self) -> FftDirection

Returns FftDirection::Forward if this instance computes forward FFTs, or FftDirection::Inverse for inverse FFTs

impl<T: FftNum> Fft<T> for MixedRadix<T>

pub fn process_outofplace_with_scratch(
    &self,
    input: &mut [Complex<T>],
    output: &mut [Complex<T>],
    scratch: &mut [Complex<T>]
)

Divides input and output into chunks of size self.len(), and computes a FFT on each chunk.

pub fn process_with_scratch(
    &self,
    buffer: &mut [Complex<T>],
    scratch: &mut [Complex<T>]
)

Divides buffer into chunks of size self.len(), and computes a FFT on each chunk.

pub fn get_inplace_scratch_len(&self) -> usize

Returns the size of the scratch buffer required by process_with_scratch

pub fn get_outofplace_scratch_len(&self) -> usize

Returns the size of the scratch buffer required by process_outofplace_with_scratch

pub fn process(&self, buffer: &mut [Complex<T>])

Computes a FFT in-place.

impl<T: FftNum> Length for MixedRadix<T>

pub fn len(&self) -> usize

The FFT size that this algorithm can process