Files
open-xiaoai/examples/stereo/src/audio/recorder.rs
T

42 lines
1.2 KiB
Rust

#![cfg(target_os = "linux")]
use crate::audio::config::AudioConfig;
use alsa::Direction;
use alsa::pcm::{Access, Format, HwParams, PCM};
use anyhow::{Context, Result};
pub struct AudioRecorder {
pcm: PCM,
}
impl AudioRecorder {
pub fn new(config: &AudioConfig) -> Result<Self> {
let pcm = PCM::new(&config.capture_device, Direction::Capture, false)
.context("Failed to open capture PCM device")?;
setup_pcm(&pcm, config.sample_rate, config.channels)?;
Ok(Self { pcm })
}
pub fn read(&self, buffer: &mut [i16]) -> Result<usize> {
self.pcm
.io_i16()?
.readi(buffer)
.context("Failed to read from capture device")
}
}
fn setup_pcm(pcm: &PCM, sample_rate: u32, channels: u16) -> Result<()> {
let hwp = HwParams::any(pcm).context("Failed to get HwParams")?;
hwp.set_access(Access::RWInterleaved)?;
hwp.set_format(Format::s16())?;
hwp.set_rate(sample_rate, alsa::ValueOr::Nearest)?;
hwp.set_channels(channels as u32)?;
pcm.hw_params(&hwp).context("Failed to set HwParams")?;
let swp = pcm.sw_params_current()?;
pcm.sw_params(&swp)?;
pcm.prepare()?;
Ok(())
}