From e35dcd918acb0347a2bb16fa3abcaa1b85c7b38c Mon Sep 17 00:00:00 2001
From: Steve Lascos <steve@blackaddr.com>
Date: Tue, 28 Jul 2020 14:31:30 -0400
Subject: [PATCH] Added noise measurements
---
examples/Tests/MeasureNoise/MeasureNoise.ino | 99 ++++++++++++++++++
src/AudioEffectRmsMeasure.h | 94 +++++++++++++++++
src/BAEffects.h | 1 +
src/effects/AudioEffectDelayExternal.cpp | 8 +-
src/effects/AudioEffectRmsMeasure.cpp | 102 +++++++++++++++++++
src/peripherals/BAAudioControlWM8731.cpp | 3 +
6 files changed, 306 insertions(+), 1 deletion(-)
create mode 100644 examples/Tests/MeasureNoise/MeasureNoise.ino
create mode 100644 src/AudioEffectRmsMeasure.h
create mode 100644 src/effects/AudioEffectRmsMeasure.cpp
diff --git a/examples/Tests/MeasureNoise/MeasureNoise.ino b/examples/Tests/MeasureNoise/MeasureNoise.ino
new file mode 100644
index 0000000..19da702
--- /dev/null
+++ b/examples/Tests/MeasureNoise/MeasureNoise.ino
@@ -0,0 +1,99 @@
+/*************************************************************************
+ * This demo uses the BALibrary library to provide enhanced control of
+ * the TGA Pro board.
+ *
+ * The latest copy of the BA Guitar library can be obtained from
+ * https://github.com/Blackaddr/BALibrary
+ *
+ * This demo measures the input noise of the TGA Pro. Make sure nothing is physically plugged
+ * into the INPUT jack when you run this program. This allows the switching-input jack to ground
+ * the input to zero signal.
+ *
+ * The test will measure RMS noise and average sample value while toggling the CODEC HPF
+ * every few seconds. the CODEC HPF attempts to maximize headroom by modulating it's digital
+ * HPF filter offset. This results in near-zero low-frequncy (DC and sub-sonic) content which can
+ * be useful for frequency detection but is not appropriate for when sound quality is desired as
+ * the modulation of the filter will result in audible artifacts.
+ *
+ */
+#include <Wire.h>
+#include <Audio.h>
+#include "BALibrary.h"
+#include "BAEffects.h"
+
+using namespace BALibrary;
+using namespace BAEffects;
+
+#define MEASURE_CODEC_PERFORMANCE // uncomment this line to measure internal codec performance, comment the line to measure TGA analog input circuitry performance.
+
+BAAudioControlWM8731 codecControl;
+AudioInputI2S i2sIn;
+AudioOutputI2S i2sOut;
+AudioEffectRmsMeasure rmsModule;
+
+// Audio Connections
+AudioConnection patchInL(i2sIn,0, rmsModule, 0); // route the input to the delay
+AudioConnection patchInR(i2sIn,1, rmsModule, 1); // route the input to the delay
+
+AudioConnection patchOutL(rmsModule, 0, i2sOut, 0); // connect the cab filter to the output.
+AudioConnection patchOutR(rmsModule, 0, i2sOut, 1); // connect the cab filter to the output.
+
+void setup() {
+
+ delay(5); // wait a few ms to make sure the GTA Pro is fully powered up
+ AudioMemory(48);
+
+ // If the codec was already powered up (due to reboot) power itd own first
+ codecControl.disable();
+ delay(100);
+ codecControl.enable();
+ delay(100);
+
+#if defined(MEASURE_CODEC_PERFORMANCE)
+ // Measure TGA board performance with input unplugged, and 0 gain. Please set
+ // the gain switch on the TGA Pro to 0 dB.
+ Serial.println("Measuring CODEC internal performance");
+ codecControl.setLeftInMute(true); // mute the input signal completely
+ codecControl.setRightInMute(true);
+ codecControl.setHPFDisable(false); // Start with the HPF enabled
+#else
+ // Measure TGA board performance with input unplugged, and 0 gain. Please set
+ // the gain switch on the TGA Pro to 0 dB.
+ Serial.println("Measuring TGA Pro analog performance");
+ codecControl.setLeftInputGain(23); // 23 = 10111 = 0 dB of CODEC analog gain
+ codecControl.setRightInputGain(23);
+ codecControl.setLeftInMute(false);
+ codecControl.setRightInMute(false);
+ codecControl.setHPFDisable(false); // Start with the HPF enabled.
+#endif
+
+ rmsModule.enable();
+ rmsModule.bypass(false);
+
+
+}
+
+unsigned loopCount = 0;
+bool isHpfEnabled = true;
+
+void loop() {
+
+ // The audio flows automatically through the Teensy Audio Library
+
+ if (loopCount > 100000000) {
+ if (isHpfEnabled) {
+ Serial.println("Setting HPF disable to true");
+ codecControl.setHPFDisable(true);
+
+ isHpfEnabled = false;
+ } else {
+ Serial.println("Setting HPF disable to false");
+ codecControl.setHPFDisable(false);
+ isHpfEnabled = true;
+ }
+ loopCount = 0;
+ }
+
+ loopCount++;
+
+}
diff --git a/src/AudioEffectRmsMeasure.h b/src/AudioEffectRmsMeasure.h
new file mode 100644
index 0000000..70270ab
--- /dev/null
+++ b/src/AudioEffectRmsMeasure.h
@@ -0,0 +1,94 @@
+/**************************************************************************//**
+ * @file
+ * @author Steve Lascos
+ * @company Blackaddr Audio
+ *
+ * @brief Measure the RMS noise of a channel
+ *
+ * @copyright This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.*
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY__BAEFFECTS_AUDIOEFFECTDELAYEXTERNAL_H; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *****************************************************************************/
+
+#ifndef __BAEFFECTS_AUDIOEFFECTRMSMEASURE_H
+#define __BAEFFECTS_AUDIOEFFECTRMSMEASURE_H
+
+#include <stdint.h>
+#include <Audio.h>
+
+namespace BAEffects {
+
+/**************************************************************************//**
+ * AudioEffectRmsMeasure
+ *****************************************************************************/
+class AudioEffectRmsMeasure : public AudioStream {
+public:
+
+ // *** CONSTRUCTORS ***
+ /// Create the measurement object. Default is to measure and calculate over
+ /// approximate 1 second when rate is roughly 44.1 KHz
+ /// @param numBlockMeasurements specifies how many audio blocks to calculate the noise
+ /// over.
+ AudioEffectRmsMeasure(unsigned numBlockMeasurements = 345);
+
+ virtual ~AudioEffectRmsMeasure(); ///< Destructor
+
+ /// Get the most recently calculated RMS value
+ /// @returns the non-normalized RMS
+ float getRms(void) { return m_rms; }
+
+ /// Get the most recently calculated dBFS value
+ /// @returns the RMS as dB with respecdt to dBFS
+ float getDb(void) { return m_dbfs; }
+
+ /// Bypass the effect.
+ /// @param byp when true, bypass wil disable the effect, when false, effect is enabled.
+ /// Note that audio still passes through when bypass is enabled.
+ void bypass(bool byp) { m_bypass = byp; }
+
+ /// Get if the effect is bypassed
+ /// @returns true if bypassed, false if not bypassed
+ bool isBypass() { return m_bypass; }
+
+ /// Toggle the bypass effect
+ void toggleBypass() { m_bypass = !m_bypass; }
+
+ /// Set the output volume.
+ /// @details The default is 1.0.
+ /// @param vol Sets the output volume between -1.0 and +1.0
+ void volume(float vol) {m_volume = vol; }
+
+ /// Enables audio processing. Note: when not enabled, CPU load is nearly zero.
+ void enable() { m_enable = true; }
+
+ /// Disables audio process. When disabled, CPU load is nearly zero.
+ void disable() { m_enable = false; }
+
+ virtual void update(void); ///< update automatically called by the Teesny Audio Library
+
+private:
+ audio_block_t *m_inputQueueArray[1];
+
+ bool m_bypass = true;
+ bool m_enable = false;
+ float m_volume = 1.0f;
+ unsigned m_numBlockMeasurements = 0;
+ unsigned m_accumulatorCount = 0;
+ int64_t m_sum = 0;
+ float m_rms = 0.0f;
+ float m_dbfs = 0.0f;
+
+};
+
+}
+
+#endif /* __BAEFFECTS_AUDIOEFFECTRMSMEASURE_H */
diff --git a/src/BAEffects.h b/src/BAEffects.h
index 50b92b0..454e53d 100644
--- a/src/BAEffects.h
+++ b/src/BAEffects.h
@@ -26,5 +26,6 @@
#include "AudioEffectAnalogDelay.h"
#include "AudioEffectSOS.h"
#include "AudioEffectTremolo.h"
+#include "AudioEffectRmsMeasure.h"
#endif /* __BAEFFECTS_H */
diff --git a/src/effects/AudioEffectDelayExternal.cpp b/src/effects/AudioEffectDelayExternal.cpp
index f81e16a..e21d947 100644
--- a/src/effects/AudioEffectDelayExternal.cpp
+++ b/src/effects/AudioEffectDelayExternal.cpp
@@ -67,6 +67,7 @@ void BAAudioEffectDelayExternal::delay(uint8_t channel, float milliseconds) {
unsigned mask = m_activeMask;
if (m_activeMask == 0) m_startUsingSPI(m_spiChannel);
m_activeMask = mask | (1<<channel);
+ Serial.print("DelayLengthInt: "); Serial.println(m_requestedDelayLength);
}
void BAAudioEffectDelayExternal::disable(uint8_t channel) {
@@ -202,7 +203,12 @@ void BAAudioEffectDelayExternal::initialize(void)
avail = memsize - m_allocated[m_mem];
- if (m_requestedDelayLength > avail) samples = avail;
+ if (m_requestedDelayLength > avail) {
+ samples = avail;
+ } else {
+ samples = m_requestedDelayLength;
+ }
+
m_memoryStart = m_allocated[m_mem];
m_allocated[m_mem] += samples;
m_memoryLength = samples;
diff --git a/src/effects/AudioEffectRmsMeasure.cpp b/src/effects/AudioEffectRmsMeasure.cpp
new file mode 100644
index 0000000..bae6439
--- /dev/null
+++ b/src/effects/AudioEffectRmsMeasure.cpp
@@ -0,0 +1,102 @@
+/*
+ * AudioEffectRmsMeasure.cpp
+ *
+ * Created on: March 7, 2020
+ * Author: slascos
+ */
+#include <arm_math.h>
+#include "BALibrary.h"
+#include "AudioEffectRmsMeasure.h"
+
+using namespace BALibrary;
+
+namespace BAEffects {
+
+AudioEffectRmsMeasure::AudioEffectRmsMeasure(unsigned numBlockMeasurements)
+: AudioStream(1, m_inputQueueArray),
+ m_numBlockMeasurements(numBlockMeasurements),
+ m_accumulatorCount(0),
+ m_sum(0),
+ m_rms(0.0f),
+ m_dbfs(0.0f)
+{
+}
+
+AudioEffectRmsMeasure::~AudioEffectRmsMeasure()
+{
+}
+
+void AudioEffectRmsMeasure::update(void)
+{
+ audio_block_t *inputAudioBlock = receiveReadOnly(); // get the next block of input samples
+
+ // Check is block is disabled
+ if (m_enable == false) {
+ // do not transmit or process any audio, return as quickly as possible.
+ if (inputAudioBlock) release(inputAudioBlock);
+ return;
+ }
+
+ // Check is block is bypassed, if so either transmit input directly or create silence
+ if (m_bypass == true) {
+ // transmit the input directly
+ if (!inputAudioBlock) {
+ // create silence
+ inputAudioBlock = allocate();
+ if (!inputAudioBlock) { return; } // failed to allocate
+ else {
+ clearAudioBlock(inputAudioBlock);
+ }
+ }
+ transmit(inputAudioBlock, 0);
+ release(inputAudioBlock);
+ return;
+ }
+
+ // Calculate the RMS noise over the specified number of audio blocks.
+ // Once the necessary blocks have been accumulated, calculate and print the
+ // RMS noise figure.
+ // RMS noise = sqrt((1/N) * (x1*x1 + x2*x2 + ...) )
+
+ // First create the square sum of the input audio block and add it to the accumulator
+ int64_t dotProduct = 0;
+ //arm_dot_prod_q15(inputAudioBlock->data, inputAudioBlock->data, AUDIO_BLOCK_SAMPLES, &dotProduct);
+ for (int i=0; i<AUDIO_BLOCK_SAMPLES; i++) {
+ dotProduct += ((int64_t)inputAudioBlock->data[i] * (int64_t)inputAudioBlock->data[i]);
+ if (dotProduct < 0) {
+ Serial.println("DOT ERROR!");
+ Serial.println(inputAudioBlock->data[i], HEX);
+ }
+ }
+ m_sum += (int64_t)(dotProduct);
+
+ m_accumulatorCount++;
+
+ // Check if we have enough samples accumulated.
+ if (m_accumulatorCount == m_numBlockMeasurements) {
+ // Calculate and print the RMS figure
+ float div = (float)m_sum / (float)(m_accumulatorCount * AUDIO_BLOCK_SAMPLES);
+ arm_sqrt_f32(div, &m_rms);
+ // dbfs = 20*log10(abs(rmsFigure)/32768.0f);
+ m_dbfs = 20.0f * log10(m_rms/32768.0f);
+
+ Serial.print("Accumulator: "); Serial.println((int)(m_sum >> 32), HEX);
+ Serial.print("RAW RMS: "); Serial.println(m_rms);
+
+ Serial.print("AudioEffectRmsMeasure: the RMS figure is "); Serial.print(m_dbfs);
+ Serial.print(" dBFS over "); Serial.print(m_accumulatorCount); Serial.println(" audio blocks");
+
+ m_sum = 0;
+ m_accumulatorCount = 0;
+
+ }
+
+ transmit(inputAudioBlock);
+ release(inputAudioBlock);
+}
+
+
+}
+
+
+
diff --git a/src/peripherals/BAAudioControlWM8731.cpp b/src/peripherals/BAAudioControlWM8731.cpp
index 1600088..5b421cd 100644
--- a/src/peripherals/BAAudioControlWM8731.cpp
+++ b/src/peripherals/BAAudioControlWM8731.cpp
@@ -95,6 +95,9 @@ constexpr int WM8731_DAC_MUTE_SHIFT = 3;
constexpr int WM8731_HPF_DISABLE_ADDR = 5;
constexpr int WM8731_HPF_DISABLE_MASK = 0x1;
constexpr int WM8731_HPF_DISABLE_SHIFT = 0;
+constexpr int WM8731_HPF_STORE_OFFSET_ADDR = 5;
+constexpr int WM8731_HPF_STORE_OFFSET_MASK = 0x10;
+constexpr int WM8731_HPF_STORE_OFFSET_SHIFT = 4;
// Register 7
constexpr int WM8731_LRSWAP_ADDR = 5;
constexpr int WM8731_LRSWAP_MASK = 0x20;