re-add noise gate

3 files changed, 22 insertions, 3 deletions

diff --git a/mumd/src/audio.rs b/mumd/src/audio.rs
index 6264879..29c5668 100644
--- a/mumd/src/audio.rs
+++ b/mumd/src/audio.rs
@@ -1,5 +1,6 @@
 pub mod input;
 pub mod output;
+pub mod transformers;
 
 use crate::audio::input::{AudioInputDevice, DefaultAudioInputDevice};
 use crate::audio::output::{AudioOutputDevice, ClientStream, DefaultAudioOutputDevice};
diff --git a/mumd/src/audio/input.rs b/mumd/src/audio/input.rs
index 162dd2c..b0e621b 100644
--- a/mumd/src/audio/input.rs
+++ b/mumd/src/audio/input.rs
@@ -4,12 +4,13 @@ use log::*;
 use tokio::sync::watch;
 
 use crate::audio::SAMPLE_RATE;
+use crate::audio::transformers::{create_noise_gate};
 use crate::error::{AudioError, AudioStream};
 use crate::state::StatePhase;
 
 pub fn callback<T: Sample>(
     mut input_sender: futures_channel::mpsc::Sender<Vec<u8>>,
-    transformers: Vec<Box<dyn Fn(&mut [f32]) -> Option<&mut [f32]> + Send + 'static>>,
+    mut transformers: Vec<Box<dyn FnMut(&mut [f32]) -> Option<&mut [f32]> + Send + 'static>>,
     frame_size: u32,
     sample_rate: u32,
     channels: u16,
@@ -39,7 +40,7 @@ pub fn callback<T: Sample>(
         while buffer.len() + data.len() > buffer_size {
             buffer.extend(data.by_ref().take(buffer_size - buffer.len()));
             let encoded = transformers
-                .iter()
+                .iter_mut()
                 .try_fold(&mut buffer[..], |acc, e| e(acc))
                 .map(|buf| opus_encoder.encode_vec_float(&*buf, buffer_size).unwrap());
 
@@ -103,7 +104,7 @@ impl DefaultAudioInputDevice {
 
         let (volume_sender, input_volume_receiver) = watch::channel::<f32>(input_volume);
 
-        let transformers = vec![];
+        let transformers = vec![Box::new(create_noise_gate(10, 0.6)) as Box<dyn FnMut(&mut [f32]) -> Option<&mut [f32]> + Send + 'static>];
 
         let input_stream = match input_supported_sample_format {
             SampleFormat::F32 => input_device.build_input_stream(
diff --git a/mumd/src/audio/transformers.rs b/mumd/src/audio/transformers.rs
new file mode 100644
index 0000000..5c9681b
--- /dev/null
+++ b/mumd/src/audio/transformers.rs
@@ -0,0 +1,17 @@
+use dasp_ring_buffer::Bounded;
+
+
+pub fn create_noise_gate(chunks: usize, mute_percentage: f32) -> impl FnMut(&mut [f32]) -> Option<&mut [f32]> {
+    let mut peaks = Bounded::from_full(vec![0.0; chunks]);
+    let mut alltime_high: f32 = 0.0;
+    move |buf: &mut [f32]| {
+        let max = buf.iter().map(|e| e.abs()).max_by(|a, b| a.partial_cmp(b).unwrap()).unwrap();
+        peaks.push(max);
+        alltime_high = alltime_high.max(max);
+        if peaks.iter().any(|e| *e >= alltime_high * mute_percentage) {
+            Some(buf)
+        } else {
+            None
+        }
+    }
+}