voxudio 0.1.1

A real-time audio processing library with ONNX runtime support
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
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104

//! 音频处理工具模块
//!
//! 提供音频加载和重采样等功能
//!
//! # 主要功能
//! - `load_audio`: 从文件加载音频数据并转换为指定采样率和声道数
//! - `resample`: 对音频数据进行重采样处理
//!
//! # 错误处理
//! 使用`OperationError`作为统一的错误类型
//!
//! # 示例
//! ```
//! use voxudio::{load_audio,resample};
//! #[tokio::main]
//! async fn main() -> anyhow::Result<()> {
//! let (audio, channels) = load_audio::<44100, _>("../asset/hello_in_cn.mp3", false).await?;
//! let resampled = resample::<44100, 48000>(&audio, channels, 2);
//! Ok(())
//! }
//! ```

use {
    crate::OperationError,
    rodio::{Decoder, Source, buffer::SamplesBuffer, source::UniformSourceIterator},
    std::{io::Cursor, path::Path},
    tokio::fs::read,
};

/// 异步加载音频文件
///
/// # 参数
/// - `SR`: 目标采样率
/// - `P`: 音频文件路径类型，需实现`AsRef<Path>`
/// - `audio_path`: 音频文件路径
/// - `mono`: 是否转换为单声道
///
/// # 返回
/// `Result<(Vec<f32>, usize), OperationError>`: 样本数组和声道数量（双声道样本交错排列），或者错误
///
/// # 示例
/// ```
/// use voxudio::load_audio;
/// #[tokio::main]
/// async fn main() -> anyhow::Result<()> {
/// let (samples, channels) = load_audio::<44100, _>("../asset/hello_in_cn.mp3", false).await?;
/// Ok(())
/// }
/// ```
pub async fn load_audio<const SR: usize, P>(
    audio_path: P,
    mono: bool,
) -> Result<(Vec<f32>, usize), OperationError>
where
    P: AsRef<Path>,
{
    let file = Cursor::new(read(audio_path).await?);
    let decoder = Decoder::new(file)?;
    let channels = if mono { 1 } else { decoder.channels() } as usize;
    let samples =
        UniformSourceIterator::new(decoder.convert_samples::<f32>(), channels as _, SR as _)
            .collect::<Vec<f32>>();

    if samples.is_empty() {
        return Err(OperationError::InputInvalid("Audio is empty.".to_owned()));
    }

    Ok((samples, channels))
}

/// 对音频数据进行重采样处理
///
/// # 参数
/// - `SSR`: 源采样率
/// - `TSR`: 目标采样率
/// - `samples`: 样本数组，双声道样本交错排列
/// - `src_channels`: 原始声道数量
/// - `tgt_channels`: 目标声道数量
///
/// # 返回
/// `Vec<f32>`: 重采样后的样本数组
///
/// # 示例
/// ```
/// use voxudio::resample;
/// let samples = vec![1.0, 2.0, 3.0, 4.0];
/// let resampled = resample::<44100, 48000>(&samples, 1, 2);
/// ```
pub fn resample<const SSR: usize, const TSR: usize>(
    samples: &[f32],
    src_channels: usize,
    tgt_channels: usize,
) -> Vec<f32> {
    if samples.is_empty() || src_channels == 0 || tgt_channels == 0 {
        return Vec::new();
    }

    UniformSourceIterator::new(
        SamplesBuffer::new(src_channels as _, SSR as _, samples),
        tgt_channels as _,
        TSR as _,
    )
    .collect()
}