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

   1 use codec2::{Codec2, Codec2Mode};
   2 use cpal::traits::DeviceTrait;
   3 use cpal::traits::HostTrait;
   4 use cpal::traits::StreamTrait;
   5 use cpal::{Sample, SampleFormat, SampleRate};
   6 use log::debug;
   7 use m17app::adapter::StreamAdapter;
   8 use m17app::app::TxHandle;
   9 use m17core::protocol::LsfFrame;
  10 use std::collections::VecDeque;
  11 use std::fs::File;
  12 use std::io::Write;
  13 use std::path::Path;
  14 use std::sync::{
  15     mpsc::{channel, Receiver, Sender},
  16     Arc, Mutex,
  17 };
  18
  19 pub fn decode_codec2<P: AsRef<Path>>(data: &[u8], out_path: P) -> Vec<i16> {
  20     let codec2 = Codec2::new(Codec2Mode::MODE_3200);
  21     let var_name = codec2;
  22     let mut codec = var_name;
  23     let mut all_samples: Vec<i16> = vec![];
  24     for i in 0..(data.len() / 8) {
  25         let mut samples = vec![0; codec.samples_per_frame()];
  26         codec.decode(&mut samples, &data[i * 8..((i + 1) * 8)]);
  27         all_samples.append(&mut samples);
  28     }
  29
  30     // dude this works
  31     let mut speech_out = File::create(out_path).unwrap();
  32     for b in &all_samples {
  33         speech_out.write_all(&b.to_le_bytes()).unwrap();
  34     }
  35     all_samples
  36 }
  37
  38 pub struct Codec2Adapter {
  39     state: Arc<Mutex<AdapterState>>,
  40     // TODO: make this configurable
  41     output_card: String,
  42 }
  43
  44 impl Codec2Adapter {
  45     pub fn new() -> Self {
  46         Self {
  47             state: Arc::new(Mutex::new(AdapterState {
  48                 tx: None,
  49                 out_buf: VecDeque::new(),
  50                 codec2: Codec2::new(Codec2Mode::MODE_3200),
  51                 end_tx: None,
  52             })),
  53             output_card: "default".to_owned(),
  54         }
  55     }
  56 }
  57
  58 struct AdapterState {
  59     tx: Option<TxHandle>,
  60     /// Circular buffer of output samples for playback
  61     out_buf: VecDeque<i16>,
  62     codec2: Codec2,
  63     end_tx: Option<Sender<()>>,
  64 }
  65
  66 impl StreamAdapter for Codec2Adapter {
  67     fn adapter_registered(&self, _id: usize, handle: TxHandle) {
  68         self.state.lock().unwrap().tx = Some(handle);
  69
  70         let (end_tx, end_rx) = channel();
  71         let state = self.state.clone();
  72         let output_card = self.output_card.clone();
  73         std::thread::spawn(move || stream_thread(end_rx, state, output_card));
  74         self.state.lock().unwrap().end_tx = Some(end_tx);
  75     }
  76
  77     fn adapter_removed(&self) {
  78         let mut state = self.state.lock().unwrap();
  79         state.tx = None;
  80         state.end_tx = None;
  81     }
  82
  83     fn tnc_started(&self) {}
  84
  85     fn tnc_closed(&self) {}
  86
  87     fn stream_began(&self, lsf: LsfFrame) {
  88         // for now we will assume:
  89         // - unencrypted
  90         // - data type is Voice (Codec2 3200), not Voice+Data
  91         // TODO: is encryption handled here or in M17App, such that we get a decrypted stream?
  92         // TODO: handle the Voice+Data combination with Codec2 1600
  93         self.state.lock().unwrap().codec2 = Codec2::new(Codec2Mode::MODE_3200);
  94     }
  95
  96     fn stream_data(&self, frame_number: u16, is_final: bool, data: Arc<[u8; 16]>) {
  97         let mut state = self.state.lock().unwrap();
  98         for encoded in data.chunks(8) {
  99             if state.out_buf.len() < 1024 {
 100                 let mut samples = [i16::EQUILIBRIUM; 160]; // while assuming 3200
 101                 state.codec2.decode(&mut samples, encoded);
 102                 // TODO: maybe get rid of VecDeque so we can decode directly into ring buffer?
 103                 for s in samples {
 104                     state.out_buf.push_back(s);
 105                 }
 106             } else {
 107                 debug!("out_buf overflow");
 108             }
 109         }
 110     }
 111 }
 112
 113 fn output_cb(data: &mut [i16], state: &Mutex<AdapterState>) {
 114     let mut state = state.lock().unwrap();
 115     debug!(
 116         "sound card wants {} samples, we have {} in the buffer",
 117         data.len(),
 118         state.out_buf.len()
 119     );
 120     for d in data {
 121         *d = state.out_buf.pop_front().unwrap_or(i16::EQUILIBRIUM);
 122     }
 123 }
 124
 125 /// Create and manage the stream from a dedicated thread since it's `!Send`
 126 fn stream_thread(end: Receiver<()>, state: Arc<Mutex<AdapterState>>, output_card: String) {
 127     let host = cpal::default_host();
 128     let device = host
 129         .output_devices()
 130         .unwrap()
 131         .find(|d| d.name().unwrap() == output_card)
 132         .unwrap();
 133     let mut configs = device.supported_output_configs().unwrap();
 134     let config = configs
 135         .find(|c| c.channels() == 1 && c.sample_format() == SampleFormat::I16)
 136         .unwrap()
 137         .with_sample_rate(SampleRate(8000));
 138     let stream = device
 139         .build_output_stream(
 140             &config.into(),
 141             move |data: &mut [i16], info: &cpal::OutputCallbackInfo| {
 142                 debug!(
 143                     "callback {:?} playback {:?}",
 144                     info.timestamp().callback,
 145                     info.timestamp().playback
 146                 );
 147                 output_cb(data, &state);
 148             },
 149             |e| {
 150                 // trigger end_tx here? always more edge cases
 151                 debug!("error occurred in codec2 playback: {e:?}");
 152             },
 153             None,
 154         )
 155         .unwrap();
 156     stream.play().unwrap();
 157     let _ = end.recv();
 158     // it seems concrete impls of Stream have a Drop implementation that will handle termination
 159 }