From bdbfa902fb78d836e2955366327b0fb3ec9dbefa Mon Sep 17 00:00:00 2001
From: xdrm-brackets <doowap31@gmail.com>
Date: Tue, 10 Apr 2018 14:20:27 +0200
Subject: [PATCH] [lib.audio-manager] added dynamic mic volume

---
 parcel/lib/audio-manager.js | 29 +++++++++++++++++++++++++----
 1 file changed, 25 insertions(+), 4 deletions(-)

diff --git a/parcel/lib/audio-manager.js b/parcel/lib/audio-manager.js
index e32ed3f..13b206c 100644
--- a/parcel/lib/audio-manager.js
+++ b/parcel/lib/audio-manager.js
@@ -13,7 +13,8 @@ export default class AudioManager{
 		/* (2) Create the MASTER gain */
 		this.master = this.ctx.createGain();
 		this.volume = this.ctx.createGain();
-			this.volume.gain.setValueAtTime(.65, 0); // input volume 65%
+		this.peaks = { low: 0, high: 0 };
+		this.volume_value = 1;
 
 		/* (3) Initialise input (typically bound from recorder) */
 		this.input = null;
@@ -61,8 +62,8 @@ export default class AudioManager{
 		/* (7) Initialise coordinator to manage received */
 		this.stack = [];
 		this.stack_size = 2;
-		this.fade_in = 0.1;
-		this.fade_out = 0.1;
+		this.fade_in    = 0.1;
+		this.fade_out   = 0.1;
 
 
 
@@ -225,11 +226,24 @@ export default class AudioManager{
 		_audioprocess.inputBuffer.copyFromChannel(buf32, 0);
 
 		/* (4) Convert for WS connection (Int16Array) */
+		this.peaks.low  = 0;
+		this.peaks.high = 0;
 		let buf16 = this.f32toi16(buf32);
 
 		/* (5) Send buffer through websocket */
 		this.ws.send(buf16);
 
+		/* (5) Adapt microphone volume if had peaks */
+		if( this.peaks.high > .01 ) // 30% saturation -> decrease
+			this.volume_value *= .8;
+
+		else if( this.peaks.low > .99 && this.volume_value*1.01 < 1 ) // 90% too low volume + less than 30% saturation -> increase
+			this.volume_value *= 1.01;
+
+		// apply new volume
+		this.volume.gain.setValueAtTime(this.volume_value, this.ctx.currentTime);
+
+
 
 
 		/* (2) WebSocket buffer stack read
@@ -339,8 +353,15 @@ export default class AudioManager{
 		let i = 0, l = buf32.length;
 
 		/* (3) Convert each value */
-		for( ; i < l ; i++ )
+		for( ; i < l ; i++ ){
 			buf16[i] = (buf32[i] < 0) ? 0x8000 * buf32[i] : 0x7FFF * buf32[i];
+			( buf32[i] > 0.9 ) && ( this.peaks.high++ );
+			( buf32[i] < 0.1 ) && ( this.peaks.low++ );
+		}
+
+		/* (4) Report peaks in percentage */
+		this.peaks.high /= l;
+		this.peaks.low  /= l;
 
 		return buf16;
 	}