Added FP-Audio library and a F32-compressor.

MicroMDAEPiano.ino

@@ -3,7 +3,7 @@
 
    MicroMDAEPiano is a port of the MDA-EPiano sound engine
    (https://sourceforge.net/projects/mda-vst/) for the Teensy-3.5/3.6 with audio shield.
-   
+
    (c)2019 H. Wirtz <wirtz@parasitstudio.de>
 
    This program is free software; you can redistribute it and/or modify
@@ -43,6 +43,7 @@
 #include <Bounce.h>
 #include <Encoder.h>
 #include "LiquidCrystalPlus_I2C.h"
+#include <OpenAudio_ArduinoLibrary.h> //for AudioConvert_I16toF32, AudioConvert_F32toI16, and AudioEffectGain_F32
 
 // [I2C] SCL: Pin 19, SDA: Pin 18 (https://www.pjrc.com/teensy/td_libs_Wire.html)
 #define LCD_I2C_ADDRESS 0x27
@@ -53,27 +54,35 @@ Encoder enc1(ENC1_PIN_A, ENC1_PIN_B);
 Bounce but1 = Bounce(BUT1_PIN, 10);  // 10 ms debounce
 
 // GUItool: begin automatically generated code
-AudioPlayQueue           queue_r;         //xy=494,404
+AudioPlayQueue_F32       queue_r;         //xy=494,404
-AudioPlayQueue           queue_l;         //xy=494,404
+AudioPlayQueue_F32       queue_l;         //xy=494,404
+AudioEffectCompressor_F32 comp_r;
+AudioEffectCompressor_F32 comp_l;
+AudioConvert_F32toI16     float2Int_r;
+AudioConvert_F32toI16     float2Int_l;
 AudioAnalyzePeak         peak_r;          //xy=695,491
 AudioAnalyzePeak         peak_l;          //xy=695,491
-AudioConnection          patchCord0(queue_l, peak_l);
+AudioConnection_F32      patchCord0(queue_r, comp_r);
-AudioConnection          patchCord1(queue_r, peak_r);
+AudioConnection_F32      patchCord1(queue_l, comp_l);
+AudioConnection_F32      patchCord2(comp_r, float2Int_r);
+AudioConnection_F32      patchCord3(comp_l, float2Int_l);
+AudioConnection          patchCord4(float2Int_r, peak_r);
+AudioConnection          patchCord5(float2Int_l, peak_l);
 #ifdef TEENSY_AUDIO_BOARD
 AudioOutputI2S           i2s1;           //xy=1072,364
-AudioConnection          patchCord2(queue_l, 0, i2s1, 0);
+AudioConnection          patchCord6(float2Int_r, 0, i2s1, 0);
-AudioConnection          patchCord3(queue_r, 0, i2s1, 1);
+AudioConnection          patchCord7(float2Int_l, 0, i2s1, 1);
 AudioControlSGTL5000     sgtl5000_1;     //xy=700,536
 #else
 AudioOutputPT8211        pt8211_1;       //xy=1079,320
 AudioAmplifier           volume_r;           //xy=818,370
 AudioAmplifier           volume_l;           //xy=818,411
-AudioConnection          patchCord2(queue_l, volume_r);
+AudioConnection          patchCord6(float2Int_r, volume_r);
-AudioConnection          patchCord3(queue_r, volume_l);
+AudioConnection          patchCord7(float2Int_l, volume_l);
-AudioConnection          patchCord4(volume_r, peak_r);
+AudioConnection          patchCord8(volume_r, peak_r);
-AudioConnection          patchCord5(volume_l, peak_l);
+AudioConnection          patchCord9(volume_l, peak_l);
-AudioConnection          patchCord6(volume_r, 0, pt8211_1, 1);
+AudioConnection          patchCord10(volume_r, 0, pt8211_1, 1);
-AudioConnection          patchCord7(volume_l, 0, pt8211_1, 0);
+AudioConnection          patchCord11(volume_l, 0, pt8211_1, 0);
 #endif
 // GUItool: end automatically generated code
 
@@ -164,6 +173,7 @@ void setup()
 
   // start audio card
   AudioMemory(AUDIO_MEM);
+  AudioMemory_F32(AUDIO_MEM_F32);
 
 #ifdef TEENSY_AUDIO_BOARD
   sgtl5000_1.enable();
@@ -205,6 +215,11 @@ void setup()
 
   // DECAY,RELEASE,HARDNESS,TREBLE,PAN_TREM,LFO_RATE,VELOCITY_SENSE,STEREO,MAX_POLY,TUNE,DETUNE,OVERDRIVE
 
+  // setup compressor as limiter
+  setup_compressor(true, -15.0f, 5.0f, 0.005f, 0.200f);
+  // setup compressor like an automatic volume control
+  //setup_compressor(true,-50.0,5.0,1.0,2.0);
+
   Serial.println(F("<setup end>"));
 
 #if defined (DEBUG) && defined (SHOW_CPU_LOAD_MSEC)
@@ -215,8 +230,8 @@ void setup()
 
 void loop()
 {
-  int16_t* audio_buffer_r; // pointer to AUDIO_BLOCK_SAMPLES * sizeof(int16_t)
+  float* audio_buffer_r; // pointer to AUDIO_BLOCK_SAMPLES * sizeof(float)
-  int16_t* audio_buffer_l; // pointer to AUDIO_BLOCK_SAMPLES * sizeof(int16_t)
+  float* audio_buffer_l; // pointer to AUDIO_BLOCK_SAMPLES * sizeof(float)
   const uint16_t audio_block_time_ms = 1000000 / (SAMPLE_RATE / AUDIO_BLOCK_SAMPLES);
 
   // Main sound calculation
@@ -255,12 +270,12 @@ void loop()
       render_time_max = t2;
     if (peak_r.available())
     {
-      if (peak_r.read() > 0.99)
+      if (peak_r.read() > 1.00)
         peak++;
     }
     if (peak_l.available())
     {
-      if (peak_l.read() > 0.99)
+      if (peak_l.read() > 1.00)
         peak++;
     }
 
@@ -278,6 +293,17 @@ void loop()
   handle_input();
 }
 
+void setup_compressor(boolean use_HP_filter, float knee_dBFS, float comp_ratio, float attack_sec, float release_sec)
+{
+  comp_r.enableHPFilter(use_HP_filter);   comp_l.enableHPFilter(use_HP_filter);
+  comp_r.setThresh_dBFS(knee_dBFS);       comp_l.setThresh_dBFS(knee_dBFS);
+  comp_r.setCompressionRatio(comp_ratio); comp_l.setCompressionRatio(comp_ratio);
+
+  float fs_Hz = AUDIO_SAMPLE_RATE;
+  comp_r.setAttack_sec(attack_sec, fs_Hz);       comp_l.setAttack_sec(attack_sec, fs_Hz);
+  comp_r.setRelease_sec(release_sec, fs_Hz);     comp_l.setRelease_sec(release_sec, fs_Hz);
+}
+
 void handle_input(void)
 {
 #ifdef USE_ONBOARD_USB_HOST
@@ -315,7 +341,7 @@ void handle_input(void)
   if (but1.update())
     ;
   // place handling of encoder and showing values on lcd here
-  
+
 }
 
 #ifdef DEBUG

config.h

@@ -32,6 +32,7 @@
 #define VOLUME 0.8
 #define DEFAULT_MIDI_CHANNEL MIDI_CHANNEL_OMNI
 #define AUDIO_MEM 300
+#define AUDIO_MEM_F32 10
 #define SAMPLE_RATE 44100
 #define REDUCE_LOUDNESS 0
 #define USE_XFADE_DATA 1

mdaEPiano.cpp

@@ -194,7 +194,7 @@ float mdaEPiano::getParameter(int32_t index)     {
   return programs[curProgram].param[index];
 }
 
-void mdaEPiano::process(int16_t *outputs_r, int16_t *outputs_l)
+void mdaEPiano::process(float *outputs_r, float *outputs_l)
 {
   int16_t v;
   float x, l, r, od = overdrive;
@@ -237,8 +237,8 @@ void mdaEPiano::process(int16_t *outputs_r, int16_t *outputs_l)
     l += l * lmod * lfo1;
     r += r * rmod * lfo1;  //worth making all these local variables?
 
-    outputs_l[frame] += static_cast<int16_t>((l * 0.5) * 0x7fff);
+    outputs_l[frame] += l;
-    outputs_r[frame] += static_cast<int16_t>((r * 0.5) * 0x7fff);
+    outputs_r[frame] += r;
   }
 
   if (fabs(tl) < 1.0e-10) tl = 0.0f; //anti-denormal

mdaEPiano.h

@@ -79,7 +79,7 @@ public:
 	 mdaEPiano(); // mdaEPiano(audioMasterCallback audioMaster);
 	~mdaEPiano();
 
-  virtual void process(int16_t *outputs_r, int16_t *outputs_l);
+  virtual void process(float *outputs_r, float *outputs_l);
   virtual bool processMidiMessage(uint8_t type, uint8_t data1, uint8_t data2);
 	virtual void setProgram(int32_t program);
 	virtual void setParameter(int32_t index, float value);