Implementing soundmodem tx path

[m17rt] / m17app / src / soundmodem.rs

diff --git a/m17app/src/soundmodem.rs b/m17app/src/soundmodem.rs
index 8b7f80f74aa4765aba9e74bd3667375c87b91c33..99085a0f72e34d0035be3f596faeb62e2749cd33 100644 (file)
--- a/m17app/src/soundmodem.rs
+++ b/m17app/src/soundmodem.rs
@@ -1,13 +1,18 @@
-use std::io::{self, ErrorKind, Read, Write};
-

 use crate::tnc::{Tnc, TncError};
 use crate::tnc::{Tnc, TncError};

+use cpal::traits::DeviceTrait;
+use cpal::traits::HostTrait;
+use cpal::traits::StreamTrait;
+use cpal::{SampleFormat, SampleRate};

 use log::debug;
 use m17core::kiss::MAX_FRAME_LEN;
 use log::debug;
 use m17core::kiss::MAX_FRAME_LEN;

-use m17core::modem::{Demodulator, SoftDemodulator};
+use m17core::modem::{Demodulator, Modulator, ModulatorAction, SoftDemodulator, SoftModulator};

 use m17core::tnc::SoftTnc;
 use m17core::tnc::SoftTnc;

+use std::collections::VecDeque;

 use std::fs::File;
 use std::fs::File;

+use std::io::{self, ErrorKind, Read, Write};

 use std::path::PathBuf;
 use std::sync::mpsc::{channel, sync_channel, Receiver, Sender, SyncSender, TryRecvError};
 use std::path::PathBuf;
 use std::sync::mpsc::{channel, sync_channel, Receiver, Sender, SyncSender, TryRecvError};

+use std::sync::RwLock;

 use std::sync::{Arc, Mutex};
 use std::time::{Duration, Instant};
 
 use std::sync::{Arc, Mutex};
 use std::time::{Duration, Instant};
 


@@ -18,11 +23,17 @@ pub struct Soundmodem {
 }
 
 impl Soundmodem {
 }
 
 impl Soundmodem {

-    pub fn new_with_input<T: InputSource>(input: T) -> Self {
+    pub fn new_with_input_and_output<I: InputSource, O: OutputSink>(input: I, output: O) -> Self {

         // must create TNC here
         let (event_tx, event_rx) = sync_channel(128);
         let (kiss_out_tx, kiss_out_rx) = sync_channel(128);
         // must create TNC here
         let (event_tx, event_rx) = sync_channel(128);
         let (kiss_out_tx, kiss_out_rx) = sync_channel(128);

-        spawn_soundmodem_worker(event_tx.clone(), event_rx, kiss_out_tx, Box::new(input));
+        spawn_soundmodem_worker(
+            event_tx.clone(),
+            event_rx,
+            kiss_out_tx,
+            Box::new(input),
+            Box::new(output),
+        );

         Self {
             event_tx,
             kiss_out_rx: Arc::new(Mutex::new(kiss_out_rx)),
         Self {
             event_tx,
             kiss_out_rx: Arc::new(Mutex::new(kiss_out_rx)),


@@ -106,6 +117,8 @@ pub enum SoundmodemEvent {
     BasebandInput(Arc<[i16]>),
     Start,
     Close,
     BasebandInput(Arc<[i16]>),
     Start,
     Close,

+    DidReadFromOutputBuffer { len: usize, timestamp: Instant },
+    OutputUnderrun,

 }
 
 fn spawn_soundmodem_worker(
 }
 
 fn spawn_soundmodem_worker(


@@ -113,13 +126,24 @@ fn spawn_soundmodem_worker(
     event_rx: Receiver<SoundmodemEvent>,
     kiss_out_tx: SyncSender<Arc<[u8]>>,
     input: Box<dyn InputSource>,
     event_rx: Receiver<SoundmodemEvent>,
     kiss_out_tx: SyncSender<Arc<[u8]>>,
     input: Box<dyn InputSource>,

+    output: Box<dyn OutputSink>,

 ) {
     std::thread::spawn(move || {
         // TODO: should be able to provide a custom Demodulator for a soundmodem
 ) {
     std::thread::spawn(move || {
         // TODO: should be able to provide a custom Demodulator for a soundmodem

-        let mut demod = SoftDemodulator::new();
+        let mut demodulator = SoftDemodulator::new();
+        let mut modulator = SoftModulator::new();

         let mut tnc = SoftTnc::new();
         let mut buf = [0u8; MAX_FRAME_LEN];
         let mut tnc = SoftTnc::new();
         let mut buf = [0u8; MAX_FRAME_LEN];

+        let out_buffer = Arc::new(RwLock::new(OutputBuffer::new()));
+        let mut out_samples = [0i16; 1024];
+        let start = Instant::now();
+        let mut ptt = false;

         while let Ok(ev) = event_rx.recv() {
         while let Ok(ev) = event_rx.recv() {

+            // Update clock on TNC before we do anything
+            let sample_time = (start.elapsed().as_nanos() / 48000) as u64;
+            tnc.set_now(sample_time);
+
+            // Handle event

             match ev {
                 SoundmodemEvent::Kiss(k) => {
                     let _n = tnc.write_kiss(&k);
             match ev {
                 SoundmodemEvent::Kiss(k) => {
                     let _n = tnc.write_kiss(&k);


@@ -128,7 +152,7 @@ fn spawn_soundmodem_worker(
                 }
                 SoundmodemEvent::BasebandInput(b) => {
                     for sample in &*b {
                 }
                 SoundmodemEvent::BasebandInput(b) => {
                     for sample in &*b {

-                        if let Some(frame) = demod.demod(*sample) {
+                        if let Some(frame) = demodulator.demod(*sample) {

                             tnc.handle_frame(frame);
                             loop {
                                 let n = tnc.read_kiss(&mut buf);
                             tnc.handle_frame(frame);
                             loop {
                                 let n = tnc.read_kiss(&mut buf);


@@ -140,9 +164,66 @@ fn spawn_soundmodem_worker(
                             }
                         }
                     }
                             }
                         }
                     }

+                    tnc.set_data_carrier_detect(demodulator.data_carrier_detect());
+                }
+                SoundmodemEvent::Start => {
+                    input.start(event_tx.clone());
+                    output.start(event_tx.clone(), out_buffer.clone());

                 }
                 }

-                SoundmodemEvent::Start => input.start(event_tx.clone()),

                 SoundmodemEvent::Close => break,
                 SoundmodemEvent::Close => break,

+                SoundmodemEvent::DidReadFromOutputBuffer { len, timestamp } => {
+                    let (occupied, internal_latency) = {
+                        let out_buffer = out_buffer.read().unwrap();
+                        (out_buffer.samples.len(), out_buffer.latency)
+                    };
+                    let internal_latency = (internal_latency.as_secs_f32() * 48000.0) as usize;
+                    let dynamic_latency =
+                        len.saturating_sub((timestamp.elapsed().as_secs_f32() * 48000.0) as usize);
+                    modulator.update_output_buffer(
+                        occupied,
+                        48000,
+                        internal_latency + dynamic_latency,
+                    );
+                }
+                SoundmodemEvent::OutputUnderrun => {
+                    // TODO: cancel transmission, send empty data frame to host
+                }
+            }
+
+            // Update PTT state
+            let new_ptt = tnc.ptt();
+            if new_ptt != ptt {
+                if new_ptt {
+                    // turn it on
+                } else {
+                    // turn it off
+                }
+            }
+            ptt = new_ptt;
+
+            // Let the modulator do what it wants
+            while let Some(action) = modulator.run() {
+                match action {
+                    ModulatorAction::SetIdle(idling) => {
+                        out_buffer.write().unwrap().idling = idling;
+                    }
+                    ModulatorAction::GetNextFrame => {
+                        modulator.provide_next_frame(tnc.read_tx_frame());
+                    }
+                    ModulatorAction::ReadOutput => loop {
+                        let n = modulator.read_output_samples(&mut out_samples);
+                        if n == 0 {
+                            break;
+                        }
+                        let mut out_buffer = out_buffer.write().unwrap();
+                        for s in &out_samples[0..n] {
+                            out_buffer.samples.push_back(*s);
+                        }
+                    },
+                    ModulatorAction::TransmissionWillEnd(in_samples) => {
+                        tnc.set_tx_end_time(in_samples);
+                    }
+                }

             }
         }
     });
             }
         }
     });


@@ -154,16 +235,69 @@ pub trait InputSource: Send + Sync + 'static {
 }
 
 pub struct InputSoundcard {
 }
 
 pub struct InputSoundcard {

-    cpal_name: String,
+    // TODO: allow for inversion both here and in output
+    cpal_name: Option<String>,
+    end_tx: Mutex<Option<Sender<()>>>,
+}
+
+impl InputSoundcard {
+    pub fn new() -> Self {
+        Self {
+            cpal_name: None,
+            end_tx: Mutex::new(None),
+        }
+    }
+
+    pub fn new_with_card(card_name: String) -> Self {
+        Self {
+            cpal_name: Some(card_name),
+            end_tx: Mutex::new(None),
+        }
+    }

 }
 
 impl InputSource for InputSoundcard {
     fn start(&self, samples: SyncSender<SoundmodemEvent>) {
 }
 
 impl InputSource for InputSoundcard {
     fn start(&self, samples: SyncSender<SoundmodemEvent>) {

-        todo!()
+        let (end_tx, end_rx) = channel();
+        let cpal_name = self.cpal_name.clone();
+        std::thread::spawn(move || {
+            let host = cpal::default_host();
+            let device = if let Some(name) = cpal_name.as_deref() {
+                host.input_devices()
+                    .unwrap()
+                    .find(|d| d.name().unwrap() == name)
+                    .unwrap()
+            } else {
+                host.default_input_device().unwrap()
+            };
+            let mut configs = device.supported_input_configs().unwrap();
+            let config = configs
+                .find(|c| c.channels() == 1 && c.sample_format() == SampleFormat::I16)
+                .unwrap()
+                .with_sample_rate(SampleRate(48000));
+            let stream = device
+                .build_input_stream(
+                    &config.into(),
+                    move |data: &[i16], _info: &cpal::InputCallbackInfo| {
+                        debug!("input has given us {} samples", data.len());
+                        let out: Vec<i16> = data.iter().map(|s| *s).collect();
+                        let _ = samples.try_send(SoundmodemEvent::BasebandInput(out.into()));
+                    },
+                    |e| {
+                        // TODO: abort?
+                        debug!("error occurred in soundcard input: {e:?}");
+                    },
+                    None,
+                )
+                .unwrap();
+            stream.play().unwrap();
+            let _ = end_rx.recv();
+        });
+        *self.end_tx.lock().unwrap() = Some(end_tx);

     }
 
     fn close(&self) {
     }
 
     fn close(&self) {

-        todo!()
+        let _ = self.end_tx.lock().unwrap().take();

     }
 }
 
     }
 }
 


@@ -225,3 +359,135 @@ impl InputSource for InputRrcFile {
         let _ = self.end_tx.lock().unwrap().take();
     }
 }
         let _ = self.end_tx.lock().unwrap().take();
     }
 }

+
+pub struct OutputBuffer {
+    idling: bool,
+    // TODO: something more efficient
+    samples: VecDeque<i16>,
+    latency: Duration,
+}
+
+impl OutputBuffer {
+    pub fn new() -> Self {
+        Self {
+            idling: true,
+            samples: VecDeque::new(),
+            latency: Duration::ZERO,
+        }
+    }
+}
+
+pub trait OutputSink: Send + Sync + 'static {
+    fn start(&self, event_tx: SyncSender<SoundmodemEvent>, buffer: Arc<RwLock<OutputBuffer>>);
+    fn close(&self);
+}
+
+pub struct OutputRrcFile {
+    path: PathBuf,
+    end_tx: Mutex<Option<Sender<()>>>,
+}
+
+impl OutputRrcFile {
+    pub fn new(path: PathBuf) -> Self {
+        Self {
+            path,
+            end_tx: Mutex::new(None),
+        }
+    }
+}
+
+impl OutputSink for OutputRrcFile {
+    fn start(&self, event_tx: SyncSender<SoundmodemEvent>, buffer: Arc<RwLock<OutputBuffer>>) {
+        let (end_tx, end_rx) = channel();
+        let path = self.path.clone();
+        std::thread::spawn(move || {
+            // TODO: error handling
+            let mut file = File::create(path).unwrap();
+
+            // assuming 48 kHz for now
+            const TICK: Duration = Duration::from_millis(25);
+            const SAMPLES_PER_TICK: usize = 1200;
+
+            // flattened BE i16s for writing
+            let mut buf = [0u8; SAMPLES_PER_TICK * 2];
+            let mut next_tick = Instant::now() + TICK;
+
+            loop {
+                std::thread::sleep(next_tick.duration_since(Instant::now()));
+                next_tick = next_tick + TICK;
+                if end_rx.try_recv() != Err(TryRecvError::Empty) {
+                    break;
+                }
+
+                let mut buffer = buffer.write().unwrap();
+                for out in buf.chunks_mut(2) {
+                    if let Some(s) = buffer.samples.pop_front() {
+                        let be = s.to_be_bytes();
+                        out.copy_from_slice(&[be[0], be[1]]);
+                    } else if buffer.idling {
+                        out.copy_from_slice(&[0, 0]);
+                    } else {
+                        debug!("output rrc file had underrun");
+                        let _ = event_tx.send(SoundmodemEvent::OutputUnderrun);
+                        break;
+                    }
+                }
+                if let Err(e) = file.write_all(&buf) {
+                    debug!("failed to write to rrc file: {e:?}");
+                    break;
+                }
+            }
+        });
+        *self.end_tx.lock().unwrap() = Some(end_tx);
+    }
+
+    fn close(&self) {
+        let _ = self.end_tx.lock().unwrap().take();
+    }
+}
+
+pub struct NullOutputSink {
+    end_tx: Mutex<Option<Sender<()>>>,
+}
+
+impl NullOutputSink {
+    pub fn new() -> Self {
+        Self {
+            end_tx: Mutex::new(None),
+        }
+    }
+}
+
+impl OutputSink for NullOutputSink {
+    fn start(&self, event_tx: SyncSender<SoundmodemEvent>, buffer: Arc<RwLock<OutputBuffer>>) {
+        let (end_tx, end_rx) = channel();
+        std::thread::spawn(move || {
+            // assuming 48 kHz for now
+            const TICK: Duration = Duration::from_millis(25);
+            const SAMPLES_PER_TICK: usize = 1200;
+            let mut next_tick = Instant::now() + TICK;
+
+            loop {
+                std::thread::sleep(next_tick.duration_since(Instant::now()));
+                next_tick = next_tick + TICK;
+                if end_rx.try_recv() != Err(TryRecvError::Empty) {
+                    break;
+                }
+
+                let mut buffer = buffer.write().unwrap();
+                for _ in 0..SAMPLES_PER_TICK {
+                    if !buffer.samples.pop_front().is_some() && !buffer.idling {
+                        debug!("null output had underrun");
+                        let _ = event_tx.send(SoundmodemEvent::OutputUnderrun);
+                        break;
+                    }
+                }
+            }
+        });
+        *self.end_tx.lock().unwrap() = Some(end_tx);
+    }
+
+    fn close(&self) {
+        let _ = self.end_tx.lock().unwrap().take();
+    }
+}