From f43706dfe1f2f2ed87b5e8793b8f1b147b56b8e7 Mon Sep 17 00:00:00 2001
From: Zach Pomerantz <zmp@umich.edu>
Date: Mon, 13 Mar 2017 18:56:54 -0400
Subject: [PATCH] clean AudioNoiseGate
---
libraries/audio/src/AudioNoiseGate.cpp | 38 ++++++--------------------
libraries/audio/src/AudioNoiseGate.h | 11 +++-----
2 files changed, 13 insertions(+), 36 deletions(-)
diff --git a/libraries/audio/src/AudioNoiseGate.cpp b/libraries/audio/src/AudioNoiseGate.cpp
index c99b31b989..604897af8a 100644
--- a/libraries/audio/src/AudioNoiseGate.cpp
+++ b/libraries/audio/src/AudioNoiseGate.cpp
@@ -19,19 +19,13 @@
const float AudioNoiseGate::CLIPPING_THRESHOLD = 0.90f;
AudioNoiseGate::AudioNoiseGate() :
- _inputBlockCounter(0),
_lastLoudness(0.0f),
- _quietestBlock(std::numeric_limits<float>::max()),
- _loudestBlock(0.0f),
_didClipInLastBlock(false),
_dcOffset(0.0f),
_measuredFloor(0.0f),
_sampleCounter(0),
_isOpen(false),
- _blocksToClose(0)
-{
-
-}
+ _blocksToClose(0) {}
void AudioNoiseGate::removeDCOffset(int16_t* samples, int numSamples) {
//
@@ -80,7 +74,7 @@ void AudioNoiseGate::gateSamples(int16_t* samples, int numSamples) {
float loudness = 0;
int thisSample = 0;
int samplesOverNoiseGate = 0;
-
+
const float NOISE_GATE_HEIGHT = 7.0f;
const int NOISE_GATE_WIDTH = 5;
const int NOISE_GATE_CLOSE_BLOCK_DELAY = 5;
@@ -88,36 +82,22 @@ void AudioNoiseGate::gateSamples(int16_t* samples, int numSamples) {
// Check clipping, and check if should open noise gate
_didClipInLastBlock = false;
-
+
for (int i = 0; i < numSamples; i++) {
thisSample = std::abs(samples[i]);
if (thisSample >= ((float) AudioConstants::MAX_SAMPLE_VALUE * CLIPPING_THRESHOLD)) {
_didClipInLastBlock = true;
}
-
+
loudness += thisSample;
// Noise Reduction: Count peaks above the average loudness
if (thisSample > (_measuredFloor * NOISE_GATE_HEIGHT)) {
samplesOverNoiseGate++;
}
}
-
+
_lastLoudness = fabs(loudness / numSamples);
-
- if (_quietestBlock > _lastLoudness) {
- _quietestBlock = _lastLoudness;
- }
- if (_loudestBlock < _lastLoudness) {
- _loudestBlock = _lastLoudness;
- }
-
- const int FRAMES_FOR_NOISE_DETECTION = 400;
- if (_inputBlockCounter++ > FRAMES_FOR_NOISE_DETECTION) {
- _quietestBlock = std::numeric_limits<float>::max();
- _loudestBlock = 0.0f;
- _inputBlockCounter = 0;
- }
-
+
// If Noise Gate is enabled, check and turn the gate on and off
float averageOfAllSampleBlocks = 0.0f;
_sampleBlocks[_sampleCounter++] = _lastLoudness;
@@ -130,7 +110,7 @@ void AudioNoiseGate::gateSamples(int16_t* samples, int numSamples) {
averageOfAllSampleBlocks += _sampleBlocks[j];
}
thisAverage /= NOISE_GATE_BLOCKS_TO_AVERAGE;
-
+
if (thisAverage < smallestSample) {
smallestSample = thisAverage;
}
@@ -138,7 +118,7 @@ void AudioNoiseGate::gateSamples(int16_t* samples, int numSamples) {
averageOfAllSampleBlocks /= NUMBER_OF_NOISE_SAMPLE_BLOCKS;
_measuredFloor = smallestSample;
_sampleCounter = 0;
-
+
}
_closedInLastBlock = false;
@@ -156,7 +136,7 @@ void AudioNoiseGate::gateSamples(int16_t* samples, int numSamples) {
}
if (!_isOpen) {
// First block after being closed gets faded to silence, we fade across
- // the entire block on fading out. All subsequent blocks are muted by being slammed
+ // the entire block on fading out. All subsequent blocks are muted by being slammed
// to zeros
if (_closedInLastBlock) {
float fadeSlope = (1.0f / numSamples);
diff --git a/libraries/audio/src/AudioNoiseGate.h b/libraries/audio/src/AudioNoiseGate.h
index d47cebf853..8430f120e5 100644
--- a/libraries/audio/src/AudioNoiseGate.h
+++ b/libraries/audio/src/AudioNoiseGate.h
@@ -19,24 +19,21 @@ const int NUMBER_OF_NOISE_SAMPLE_BLOCKS = 300;
class AudioNoiseGate {
public:
AudioNoiseGate();
-
+
void gateSamples(int16_t* samples, int numSamples);
void removeDCOffset(int16_t* samples, int numSamples);
-
+
bool clippedInLastBlock() const { return _didClipInLastBlock; }
bool closedInLastBlock() const { return _closedInLastBlock; }
bool openedInLastBlock() const { return _openedInLastBlock; }
bool isOpen() const { return _isOpen; }
float getMeasuredFloor() const { return _measuredFloor; }
float getLastLoudness() const { return _lastLoudness; }
-
+
static const float CLIPPING_THRESHOLD;
-
+
private:
- int _inputBlockCounter;
float _lastLoudness;
- float _quietestBlock;
- float _loudestBlock;
bool _didClipInLastBlock;
float _dcOffset;
float _measuredFloor;