From c47d80574e61e49564ff281e38fc584ac65fc6ba Mon Sep 17 00:00:00 2001
From: Ken Cooke <ken@highfidelity.io>
Date: Tue, 23 May 2017 15:32:41 -0700
Subject: [PATCH] Replace the other noise gate, in Agent.cpp

---
 assignment-client/src/Agent.cpp | 54 ++++++++++++++++++++++++---------
 assignment-client/src/Agent.h   |  5 +--
 2 files changed, 42 insertions(+), 17 deletions(-)

diff --git a/assignment-client/src/Agent.cpp b/assignment-client/src/Agent.cpp
index 5864cadc15..ef396a06b3 100644
--- a/assignment-client/src/Agent.cpp
+++ b/assignment-client/src/Agent.cpp
@@ -55,7 +55,8 @@ static const int RECEIVED_AUDIO_STREAM_CAPACITY_FRAMES = 10;
 
 Agent::Agent(ReceivedMessage& message) :
     ThreadedAssignment(message),
-    _receivedAudioStream(RECEIVED_AUDIO_STREAM_CAPACITY_FRAMES, RECEIVED_AUDIO_STREAM_CAPACITY_FRAMES)
+    _receivedAudioStream(RECEIVED_AUDIO_STREAM_CAPACITY_FRAMES, RECEIVED_AUDIO_STREAM_CAPACITY_FRAMES),
+    _audioGate(AudioConstants::SAMPLE_RATE, AudioConstants::MONO)
 {
     _entityEditSender.setPacketsPerSecond(DEFAULT_ENTITY_PPS_PER_SCRIPT);
     DependencyManager::get<EntityScriptingInterface>()->setPacketSender(&_entityEditSender);
@@ -397,16 +398,23 @@ void Agent::executeScript() {
         QByteArray audio(frame->data);
 
         if (_isNoiseGateEnabled) {
-            static int numSamples = AudioConstants::NETWORK_FRAME_SAMPLES_PER_CHANNEL;
-            _noiseGate.gateSamples(reinterpret_cast<int16_t*>(audio.data()), numSamples);
+            int16_t* samples = reinterpret_cast<int16_t*>(audio.data());
+            int numSamples = AudioConstants::NETWORK_FRAME_SAMPLES_PER_CHANNEL;
+            _audioGate.render(samples, samples, numSamples);
         }
 
         computeLoudness(&audio, scriptedAvatar);
 
-        // the codec needs a flush frame before sending silent packets, so
-        // do not send one if the gate closed in this block (eventually this can be crossfaded).
+        // state machine to detect gate opening and closing
+        bool audioGateOpen = (scriptedAvatar->getAudioLoudness() != 0.0f);
+        bool openedInLastBlock = !_audioGateOpen && audioGateOpen;  // the gate just opened
+        bool closedInLastBlock = _audioGateOpen && !audioGateOpen;  // the gate just closed
+        _audioGateOpen = audioGateOpen;
+
+        // the codec must be flushed to silence before sending silent packets,
+        // so delay the transition to silent packets by one packet after becoming silent.
         auto packetType = PacketType::MicrophoneAudioNoEcho;
-        if (scriptedAvatar->getAudioLoudness() == 0.0f && !_noiseGate.closedInLastBlock()) {
+        if (!audioGateOpen && !closedInLastBlock) {
             packetType = PacketType::SilentAudioFrame;
         }
 
@@ -619,19 +627,35 @@ void Agent::encodeFrameOfZeros(QByteArray& encodedZeros) {
 }
 
 void Agent::computeLoudness(const QByteArray* decodedBuffer, QSharedPointer<ScriptableAvatar> scriptableAvatar) {
-    float loudness = 0.0f;
+    //float loudness = 0.0f;
+    //if (decodedBuffer) {
+    //    auto soundData = reinterpret_cast<const int16_t*>(decodedBuffer->constData());
+    //    int numFrames = decodedBuffer->size() / sizeof(int16_t);
+    //    // now iterate and come up with average
+    //    if (numFrames > 0) {
+    //        for(int i = 0; i < numFrames; i++) {
+    //            loudness += (float) std::abs(soundData[i]);
+    //        }
+    //        loudness /= numFrames;
+    //    }
+    //}
+    //scriptableAvatar->setAudioLoudness(loudness);
+
+    float lastInputLoudness = 0.0f;
     if (decodedBuffer) {
-        auto soundData = reinterpret_cast<const int16_t*>(decodedBuffer->constData());
-        int numFrames = decodedBuffer->size() / sizeof(int16_t);
-        // now iterate and come up with average
-        if (numFrames > 0) {
-            for(int i = 0; i < numFrames; i++) {
-                loudness += (float) std::abs(soundData[i]);
+        auto samples = reinterpret_cast<const int16_t*>(decodedBuffer->constData());
+        int numSamples = decodedBuffer->size() / AudioConstants::SAMPLE_SIZE;
+
+        assert(numSamples < 65536); // int32_t loudness cannot overflow
+        if (numSamples > 0) {
+            int32_t loudness = 0;
+            for (int i = 0; i < numSamples; ++i) {
+                loudness += std::abs((int32_t)samples[i]);
             }
-            loudness /= numFrames;
+            lastInputLoudness = (float)loudness / numSamples;
         }
     }
-    scriptableAvatar->setAudioLoudness(loudness);
+    scriptableAvatar->setAudioLoudness(lastInputLoudness);
 }
 
 void Agent::processAgentAvatarAudio() {
diff --git a/assignment-client/src/Agent.h b/assignment-client/src/Agent.h
index 2a156aba18..edba366601 100644
--- a/assignment-client/src/Agent.h
+++ b/assignment-client/src/Agent.h
@@ -29,7 +29,7 @@
 
 #include <plugins/CodecPlugin.h>
 
-#include "AudioNoiseGate.h"
+#include "AudioGate.h"
 #include "MixedAudioStream.h"
 #include "avatars/ScriptableAvatar.h"
 
@@ -111,7 +111,8 @@ private:
     QTimer* _avatarIdentityTimer = nullptr;
     QHash<QUuid, quint16> _outgoingScriptAudioSequenceNumbers;
 
-    AudioNoiseGate _noiseGate;
+    AudioGate _audioGate;
+    bool _audioGateOpen { false };
     bool _isNoiseGateEnabled { false };
 
     CodecPluginPointer _codec;