rustdct 0.6.0

Compute Discrete Cosine Transforms (DCT) of any size in O(nlogn) time, in pure Rust.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36

extern crate rand;

use std::f32;

use self::rand::distributions::{IndependentSample, Normal};
use self::rand::{SeedableRng, StdRng};

pub fn fuzzy_cmp(a: f32, b: f32, tolerance: f32) -> bool {
    a >= b - tolerance && a <= b + tolerance
}

pub fn compare_float_vectors(expected: &[f32], observed: &[f32]) -> bool {
    assert_eq!(expected.len(), observed.len());

    let tolerance: f32 = 0.001;

    for i in 0..expected.len() {
        if !fuzzy_cmp(observed[i], expected[i], tolerance) {
            return false;
        }
    }
    true
}

pub fn random_signal(length: usize) -> Vec<f32> {
    let mut sig = Vec::with_capacity(length);
    let normal_dist = Normal::new(0.0, 10.0);

    let seed: [usize; 5] = [1910, 11431, 4984, 14828, length];
    let mut rng: StdRng = SeedableRng::from_seed(&seed[..]);

    for _ in 0..length {
        sig.push(normal_dist.ind_sample(&mut rng) as f32);
    }
    return sig;
}