[RUST/HOUND] WavWriter 구조체 : write_sample 메소드를 사용해 백색 잡음(white noise) WAV 파일 생성하기

■ WavWriter 구조체의 write_sample 메소드를 사용해 백색 잡음(white noise)의 WAV 파일을 생성하는 방법을 보여준다.

▶ Cargo.toml


[package]
name = "test_project"
version = "0.1.0"
edition = "2021"

[dependencies]
hound = "3.4.0"
rand = "0.8.4"

[package]

name = "test_project"

version = "0.1.0"

edition = "2021"

[dependencies]

hound = "3.4.0"

rand = "0.8.4"

▶ src/main.rs


use std::fs;
use std::io;

use hound;
use rand::prelude::*;

const SAMPLE_RATE : f32 = 44100.0;

fn main()
{
    let wav_spec : hound::WavSpec = hound::WavSpec
    {
        channels        : 1,
        sample_rate     : SAMPLE_RATE as u32,
        bits_per_sample : 32,
        sample_format   : hound::SampleFormat::Float
    };

    let mut wave_writer : hound::WavWriter<io::BufWriter<fs::File>> = hound::WavWriter::create("d:/noise.wav", wav_spec).unwrap();

    let mut wave_vector : Vec<f32> = vec![];

    let bpm : usize = 120;

    wave_vector.extend(get_noise_wave_vector(2.0, -1.0, calculate_note_length(bpm, 2)));
    wave_vector.extend(get_noise_wave_vector(0.2,  0.8, calculate_note_length(bpm, 2)));
    wave_vector.extend(get_noise_wave_vector(0.8, -1.0, calculate_note_length(bpm, 2)));

    for value in wave_vector.into_iter()
    {
        wave_writer.write_sample(value).unwrap();
    }
}

// bpm  : 분당 박자, beats per minute
// note : 음표 예) 4(4분 음표)
fn calculate_note_length(bpm : usize, note: usize) -> usize
{
    return ((4.0 / note as f32) * (60.0 / bpm as f32) * SAMPLE_RATE) as usize;
}

// range       : 범위
// shift       : 시프트
// note_length : 음표 길이 (샘플 수)
fn get_noise_wave_vector(range : f32, shift : f32, note_length : usize) -> Vec<f32>
{
    let mut wave_vector : Vec<f32> = vec![0.0; note_length];

    let mut thread_rng : ThreadRng = rand::thread_rng();

    for i in 0..note_length
    {
        wave_vector[i] = thread_rng.gen::<f32>() * range + shift;
    }

    let gain : f32 = 0.5;

    return wave_vector.into_iter().map(|v : f32| (v * gain) as f32).collect();
}

use std::fs;

use std::io;

use hound;

use rand::prelude::*;

const SAMPLE_RATE : f32 = 44100.0;

fn main()

{

let wav_spec : hound::WavSpec = hound::WavSpec

{

channels : 1,

sample_rate : SAMPLE_RATE as u32,

bits_per_sample : 32,

sample_format : hound::SampleFormat::Float

};

let mut wave_writer : hound::WavWriter<io::BufWriter<fs::File>> = hound::WavWriter::create("d:/noise.wav", wav_spec).unwrap();

let mut wave_vector : Vec<f32> = vec![];

let bpm : usize = 120;

wave_vector.extend(get_noise_wave_vector(2.0, -1.0, calculate_note_length(bpm, 2)));

wave_vector.extend(get_noise_wave_vector(0.2, 0.8, calculate_note_length(bpm, 2)));

wave_vector.extend(get_noise_wave_vector(0.8, -1.0, calculate_note_length(bpm, 2)));

for value in wave_vector.into_iter()

{

wave_writer.write_sample(value).unwrap();

}

// bpm : 분당 박자, beats per minute

// note : 음표 예) 4(4분 음표)

fn calculate_note_length(bpm : usize, note: usize) -> usize

{

return ((4.0 / note as f32) * (60.0 / bpm as f32) * SAMPLE_RATE) as usize;

}

// range : 범위

// shift : 시프트

// note_length : 음표 길이 (샘플 수)

fn get_noise_wave_vector(range : f32, shift : f32, note_length : usize) -> Vec<f32>

{

let mut wave_vector : Vec<f32> = vec![0.0; note_length];

let mut thread_rng : ThreadRng = rand::thread_rng();

for i in 0..note_length

{

wave_vector[i] = thread_rng.gen::<f32>() * range + shift;

}

let gain : f32 = 0.5;

return wave_vector.into_iter().map(|v : f32| (v * gain) as f32).collect();

}

test_project.zip