code.octet-stream.net Git - m17rt/blob - m17codec2/src/lib.rs

   1 use codec2::{Codec2, Codec2Mode};
   2
   3 use m17app::adapter::StreamAdapter;
   4 use m17app::app::TxHandle;
   5 use m17core::protocol::LsfFrame;
   6
   7 use std::collections::VecDeque;
   8 use std::fs::File;
   9 use std::io::Write;
  10 use std::path::Path;
  11 use std::sync::{
  12     mpsc::{channel, Receiver, Sender},
  13     Arc, Mutex,
  14 };
  15
  16 use cpal::traits::DeviceTrait;
  17 use cpal::traits::HostTrait;
  18 use cpal::traits::StreamTrait;
  19 use cpal::{Sample, SampleFormat, SampleRate};
  20
  21 use log::debug;
  22
  23 pub fn decode_codec2<P: AsRef<Path>>(data: &[u8], out_path: P) -> Vec<i16> {
  24     let codec2 = Codec2::new(Codec2Mode::MODE_3200);
  25     let var_name = codec2;
  26     let mut codec = var_name;
  27     let mut all_samples: Vec<i16> = vec![];
  28     for i in 0..(data.len() / 8) {
  29         let mut samples = vec![0; codec.samples_per_frame()];
  30         codec.decode(&mut samples, &data[i * 8..((i + 1) * 8)]);
  31         all_samples.append(&mut samples);
  32     }
  33
  34     // dude this works
  35     let mut speech_out = File::create(out_path).unwrap();
  36     for b in &all_samples {
  37         speech_out.write_all(&b.to_le_bytes()).unwrap();
  38     }
  39     all_samples
  40 }
  41
  42 pub struct Codec2Adapter {
  43     state: Arc<Mutex<AdapterState>>,
  44     // TODO: make this configurable
  45     output_card: String,
  46 }
  47
  48 impl Codec2Adapter {
  49     pub fn new() -> Self {
  50         Self {
  51             state: Arc::new(Mutex::new(AdapterState {
  52                 tx: None,
  53                 out_buf: VecDeque::new(),
  54                 codec2: Codec2::new(Codec2Mode::MODE_3200),
  55                 end_tx: None,
  56             })),
  57             output_card: "default".to_owned(),
  58         }
  59     }
  60 }
  61
  62 struct AdapterState {
  63     tx: Option<TxHandle>,
  64     /// Circular buffer of output samples for playback
  65     out_buf: VecDeque<i16>,
  66     codec2: Codec2,
  67     end_tx: Option<Sender<()>>,
  68 }
  69
  70 impl StreamAdapter for Codec2Adapter {
  71     fn adapter_registered(&self, _id: usize, handle: TxHandle) {
  72         self.state.lock().unwrap().tx = Some(handle);
  73
  74         let (end_tx, end_rx) = channel();
  75         let state = self.state.clone();
  76         let output_card = self.output_card.clone();
  77         std::thread::spawn(move || stream_thread(end_rx, state, output_card));
  78         self.state.lock().unwrap().end_tx = Some(end_tx);
  79     }
  80
  81     fn adapter_removed(&self) {
  82         let mut state = self.state.lock().unwrap();
  83         state.tx = None;
  84         state.end_tx = None;
  85     }
  86
  87     fn tnc_started(&self) {}
  88
  89     fn tnc_closed(&self) {}
  90
  91     fn stream_began(&self, lsf: LsfFrame) {
  92         // for now we will assume:
  93         // - unencrypted
  94         // - data type is Voice (Codec2 3200), not Voice+Data
  95         // TODO: is encryption handled here or in M17App, such that we get a decrypted stream?
  96         // TODO: handle the Voice+Data combination with Codec2 1600
  97         self.state.lock().unwrap().codec2 = Codec2::new(Codec2Mode::MODE_3200);
  98     }
  99
 100     fn stream_data(&self, frame_number: u16, is_final: bool, data: Arc<[u8; 16]>) {
 101         let mut state = self.state.lock().unwrap();
 102         for encoded in data.chunks(8) {
 103             if state.out_buf.len() < 1024 {
 104                 let mut samples = [i16::EQUILIBRIUM; 160]; // while assuming 3200
 105                 state.codec2.decode(&mut samples, encoded);
 106                 // TODO: maybe get rid of VecDeque so we can decode directly into ring buffer?
 107                 for s in samples {
 108                     state.out_buf.push_back(s);
 109                 }
 110             } else {
 111                 debug!("out_buf overflow");
 112             }
 113         }
 114     }
 115 }
 116
 117 fn output_cb(data: &mut [i16], state: &Mutex<AdapterState>) {
 118     let mut state = state.lock().unwrap();
 119     debug!(
 120         "sound card wants {} samples, we have {} in the buffer",
 121         data.len(),
 122         state.out_buf.len()
 123     );
 124     for d in data {
 125         *d = state.out_buf.pop_front().unwrap_or(i16::EQUILIBRIUM);
 126     }
 127 }
 128
 129 /// Create and manage the stream from a dedicated thread since it's `!Send`
 130 fn stream_thread(end: Receiver<()>, state: Arc<Mutex<AdapterState>>, output_card: String) {
 131     let host = cpal::default_host();
 132     let device = host
 133         .output_devices()
 134         .unwrap()
 135         .find(|d| d.name().unwrap() == output_card)
 136         .unwrap();
 137     let mut configs = device.supported_output_configs().unwrap();
 138     let config = configs
 139         .find(|c| c.channels() == 1 && c.sample_format() == SampleFormat::I16)
 140         .unwrap()
 141         .with_sample_rate(SampleRate(8000));
 142     let stream = device
 143         .build_output_stream(
 144             &config.into(),
 145             move |data: &mut [i16], _: &cpal::OutputCallbackInfo| {
 146                 output_cb(data, &state);
 147             },
 148             |e| {
 149                 // trigger end_tx here? always more edge cases
 150                 debug!("error occurred in codec2 playback: {e:?}");
 151             },
 152             None,
 153         )
 154         .unwrap();
 155     stream.play().unwrap();
 156     let _ = end.recv();
 157     // it seems concrete impls of Stream have a Drop implementation that will handle termination
 158 }