Files
open-xiaoai/packages/client-v2/src/audio/reader.rs
T

144 lines
4.6 KiB
Rust

#![cfg(not(target_os = "linux"))]
use anyhow::{Context, Result};
use std::fs::File;
use std::path::Path;
use symphonia::core::audio::SampleBuffer;
use symphonia::core::codecs::{Decoder, DecoderOptions};
use symphonia::core::formats::{FormatOptions, FormatReader};
use symphonia::core::io::MediaSourceStream;
use symphonia::core::meta::MetadataOptions;
use symphonia::core::probe::Hint;
pub struct AudioReader {
format: Box<dyn FormatReader>,
decoder: Box<dyn Decoder>,
track_id: u32,
sample_buf: Option<SampleBuffer<i16>>,
left_buffer: Vec<i16>,
right_buffer: Vec<i16>,
pub channels: usize,
pub sample_rate: u32,
}
impl AudioReader {
pub fn new(path: impl AsRef<Path>) -> Result<Self> {
let path_ref = path.as_ref();
let src =
File::open(path_ref).context(format!("Failed to open audio file: {:?}", path_ref))?;
let mss = MediaSourceStream::new(Box::new(src), Default::default());
let mut hint = Hint::new();
if let Some(ext) = path_ref.extension().and_then(|s| s.to_str()) {
hint.with_extension(ext);
}
let probed = symphonia::default::get_probe()
.format(
&hint,
mss,
&FormatOptions::default(),
&MetadataOptions::default(),
)
.context("Failed to probe audio format")?;
let format = probed.format;
let track = format
.tracks()
.iter()
.find(|t| t.codec_params.codec != symphonia::core::codecs::CODEC_TYPE_NULL)
.context("No supported audio track found")?;
let track_id = track.id;
let decoder = symphonia::default::get_codecs()
.make(&track.codec_params, &DecoderOptions::default())
.context("Failed to create decoder")?;
let channels = track.codec_params.channels.map(|c| c.count()).unwrap_or(1);
let sample_rate = track.codec_params.sample_rate.unwrap_or(44100);
Ok(Self {
format,
decoder,
track_id,
sample_buf: None,
channels,
sample_rate,
left_buffer: Vec::new(),
right_buffer: Vec::new(),
})
}
pub fn read_chunk(&mut self, chunk_size: usize) -> Result<Option<(Vec<i16>, Vec<i16>)>> {
while self.left_buffer.len() < chunk_size {
if let Some((l, r)) = self.read_frame_internal()? {
self.left_buffer.extend(l);
self.right_buffer.extend(r);
} else {
break;
}
}
if self.left_buffer.is_empty() {
return Ok(None);
}
let actual_size = std::cmp::min(chunk_size, self.left_buffer.len());
let left = self.left_buffer.drain(0..actual_size).collect();
let right = self.right_buffer.drain(0..actual_size).collect();
Ok(Some((left, right)))
}
fn read_frame_internal(&mut self) -> Result<Option<(Vec<i16>, Vec<i16>)>> {
loop {
let packet = match self.format.next_packet() {
Ok(packet) => packet,
Err(symphonia::core::errors::Error::IoError(ref e))
if e.kind() == std::io::ErrorKind::UnexpectedEof =>
{
return Ok(None);
}
Err(e) => return Err(e.into()),
};
if packet.track_id() != self.track_id {
continue;
}
let decoded = self
.decoder
.decode(&packet)
.context("Failed to decode packet")?;
if self.sample_buf.is_none() {
self.sample_buf = Some(SampleBuffer::<i16>::new(
decoded.capacity() as u64,
*decoded.spec(),
));
}
if let Some(buf) = self.sample_buf.as_mut() {
buf.copy_interleaved_ref(decoded);
let samples = buf.samples();
let mut left = Vec::with_capacity(samples.len() / self.channels);
let mut right = Vec::with_capacity(samples.len() / self.channels);
if self.channels == 2 {
for i in (0..samples.len()).step_by(2) {
left.push(samples[i]);
right.push(samples[i + 1]);
}
} else {
for &s in samples {
left.push(s);
right.push(s);
}
}
return Ok(Some((left, right)));
}
}
}
}