Examples: Adding AudioEffectMine

examples/MyAudioEffect_Float/AudioEffectMine_F32.h

@@ -0,0 +1,90 @@
+
+/*
+   AudioEffectMine
+
+   Created: Chip Audette, December 2016
+   Purpose; Here is the skeleton of a audio processing algorithm that will
+       (hopefully) make it easier for people to start making their own 
+       algorithm.
+  
+   This processes a single stream fo audio data (ie, it is mono)
+
+   MIT License.  use at your own risk.
+*/
+
+#include <arm_math.h> //ARM DSP extensions.  https://www.keil.com/pack/doc/CMSIS/DSP/html/index.html
+#include <AudioStream_F32.h>
+
+class AudioEffectMine_F32 : public AudioStream_F32
+{
+   public:
+    //constructor
+    AudioEffectMine_F32(void) : AudioStream_F32(1, inputQueueArray_f32) {
+      //do any setup activities here
+    };
+
+    //here's the method that is called automatically by the Teensy Audio Library
+    void update(void) {
+      //Serial.println("AudioEffectMine_F32: doing update()");  //for debugging.
+      audio_block_f32_t *audio_block;
+      audio_block = AudioStream_F32::receiveWritable_f32();
+      if (!audio_block) return;
+
+      //do your work
+      applyMyAlgorithm(audio_block);
+
+      ///transmit the block and release memory
+      AudioStream_F32::transmit(audio_block);
+      AudioStream_F32::release(audio_block);
+    }
+
+    // !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!11
+    // Here is where you can add your algorithm.
+    // This function gets called block-wise...which is usually hard-coded to every 128 samples
+    void applyMyAlgorithm(audio_block_f32_t *audio_block) {
+      
+      //Add whatever you'd like here.  I'm going to show a couple of examples below.
+      //you can delete all of these examples.  They're just to illustrate.
+      //More examples of fast (DSP accelerated) operations are at: https://github.com/chipaudette/OpenAudio/blob/master/Docs/Programming%20Algorithms/Using%20DSP%20Exentions.md
+
+      // //apply a fixed gain...the whole block is processed with this one command
+      //float32_t gain = 2.0;  %here's 6 dB of gain
+      //arm_scale_f32(audio_block->data, gain, audio_block->data, audio_block->length); //uses ARM DSP for speed!
+
+      // //compute the power of each sample...the whole block is processed with this one command
+      // audio_block_f32_t *audio_pow_block = AudioStream_F32::allocate_f32();
+      // arm_mult_f32(audio_block->data, audio_block->data, audio_pow_block->data, audio_block->length);
+
+      // //loop over each sample and do something on a point-by-point basis (when it cannot be done as a block)
+      //for (int i=0; i < audio_block->length; i++) {
+      //  //as a boring example, let's add the user_parameter value to every sample.  yes, this
+      //  //addition operation could have been done with a DSP-accelerated function, but I'm 
+      //  //simply trying to illustrate how to loop on your audio samples.
+      //  audio_block->data[i] = audio_block->data[i] + user_parameter;  
+      //}
+
+      // //clean up...if you allocated any memory in the lines above
+      //Audiostream_F32::release(audio_pow_block);
+    } //end of applyMyAlgorithms
+    // !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+
+    // Call this method in your main program if you want to set the value of your user parameter. 
+    // The user parameter can be used in your algorithm above.  The user_parameter variable was
+    // created in the "private:" section of this class, which appears a little later in this file.
+    // Feel free to create more user parameters (and to use better names for your variables)
+    // for use in this class.
+    float32_t setUserParameter(float val) {
+      return user_parameter = val;
+    }
+ 
+  private:
+    //state-related variables
+    audio_block_f32_t *inputQueueArray_f32[1]; //memory pointer for the input to this module
+
+    //this value can be set from the outside (such as from the potentiometer) to control
+    //a parameter within your algorithm
+    float32_t user_parameter = 0.0;   
+
+};  //end class definition for AudioEffectMine_F32
+

examples/MyAudioEffect_Float/MyAudioEffect_Float.ino

@@ -0,0 +1,138 @@
+/*
+   BasicGain
+
+   Created: Chip Audette, Dec 2016
+   Purpose: Be a blank canvas for adding your own floating-point audio processing.
+
+   Uses Teensy Audio Adapter.
+   Assumes microphones (or whatever) are attached to the LINE IN (stereo)
+   Listens  potentiometer mounted to Audio Board to provde a control signal.
+
+   MIT License.  use at your own risk.
+*/
+
+//These are the includes from the Teensy Audio Library
+#include <Audio.h>      //Teensy Audio Library
+#include <Wire.h>
+#include <SPI.h>
+#include <SD.h>
+#include <SerialFlash.h>
+
+#include <OpenAudio_ArduinoLibrary.h> //for AudioConvert_I16toF32, AudioConvert_F32toI16, and AudioEffectGain_F32
+#include "AudioEffectMine_F32.h";
+
+//create audio library objects for handling the audio
+AudioControlSGTL5000    sgtl5000_1;    //controller for the Teensy Audio Board
+AudioInputI2S           i2s_in;        //Digital audio *from* the Teensy Audio Board ADC.  Sends Int16.  Stereo.
+AudioOutputI2S          i2s_out;       //Digital audio *to* the Teensy Audio Board DAC.  Expects Int16.  Stereo
+AudioConvert_I16toF32   int2Float1, int2Float2;    //Converts Int16 to Float.  See class in AudioStream_F32.h
+AudioEffectMine_F32     effect1, effect2;  //This is your own algorithms
+AudioConvert_F32toI16   float2Int1, float2Int2;    //Converts Float to Int16.  See class in AudioStream_F32.h
+
+//Make all of the audio connections
+AudioConnection         patchCord1(i2s_in, 0, int2Float1, 0);    //connect the Left input to the Left Int->Float converter
+AudioConnection         patchCord2(i2s_in, 1, int2Float2, 0);    //connect the Right input to the Right Int->Float converter
+AudioConnection_F32     patchCord10(int2Float1, 0, effect1, 0);    //Left.  makes Float connections between objects
+AudioConnection_F32     patchCord11(int2Float2, 0, effect2, 0);    //Right.  makes Float connections between objects
+AudioConnection_F32     patchCord12(effect1, 0, float2Int1, 0);    //Left.  makes Float connections between objects
+AudioConnection_F32     patchCord13(effect2, 0, float2Int2, 0);    //Right.  makes Float connections between objects
+AudioConnection         patchCord20(float2Int1, 0, i2s_out, 0);  //connect the Left float processor to the Left output
+AudioConnection         patchCord21(float2Int2, 0, i2s_out, 1);  //connect the Right float processor to the Right output
+
+// which input on the audio shield will be used?
+const int myInput = AUDIO_INPUT_LINEIN;
+//const int myInput = AUDIO_INPUT_MIC;
+
+//I have a potentiometer on the Teensy Audio Board
+#define POT_PIN A1  //potentiometer is tied to this pin
+
+// define the setup() function, the function that is called once when the device is booting
+void setup() {
+  Serial.begin(115200);   //open the USB serial link to enable debugging messages
+  delay(500);             //give the computer's USB serial system a moment to catch up.
+  Serial.println("OpenAudio_ArduinoLibrary: MyAudioEffect_Float...");
+
+  // Audio connections require memory
+  AudioMemory(10);      //allocate Int16 audio data blocks
+  AudioMemory_F32(10);  //allocate Float32 audio data blocks
+
+  // Enable the audio shield, select input, and enable output
+  sgtl5000_1.enable();                   //start the audio board
+  sgtl5000_1.inputSelect(myInput);       //choose line-in or mic-in
+  sgtl5000_1.volume(0.8);                //volume can be 0.0 to 1.0.  0.5 seems to be the usual default.
+  sgtl5000_1.lineInLevel(10, 10);        //level can be 0 to 15.  5 is the Teensy Audio Library's default
+  sgtl5000_1.adcHighPassFilterDisable(); //reduces noise.  https://forum.pjrc.com/threads/27215-24-bit-audio-boards?p=78831&viewfull=1#post78831
+
+  // setup any other other features
+  pinMode(POT_PIN, INPUT); //set the potentiometer's input pin as an INPUT
+
+} //end setup()
+
+
+// define the loop() function, the function that is repeated over and over for the life of the device
+void loop() {
+  //choose to sleep ("wait for interrupt") instead of spinning our wheels doing nothing but consuming power
+  asm(" WFI");  //ARM-specific.  Will wake on next interrupt.  The audio library issues tons of interrupts, so we wake up often.
+
+  //service the potentiometer...if enough time has passed
+  servicePotentiometer(millis());
+
+  //update the memory and CPU usage...if enough time has passed
+  printMemoryAndCPU(millis());
+} //end loop()
+
+
+//servicePotentiometer: listens to the blue potentiometer and sends the new pot value
+//  to the audio processing algorithm as a control parameter
+void servicePotentiometer(unsigned long curTime_millis) {
+  static unsigned long updatePeriod_millis = 100; //how many milliseconds between updating the potentiometer reading?
+  static unsigned long lastUpdate_millis = 0;
+  static float prev_val = 0;
+
+  //has enough time passed to update everything?
+  if (curTime_millis < lastUpdate_millis) lastUpdate_millis = 0; //handle wrap-around of the clock
+  if ((curTime_millis - lastUpdate_millis) > updatePeriod_millis) { //is it time to update the user interface?
+
+    //read potentiometer
+    float val = float(analogRead(POT_PIN)) / 1024.0; //0.0 to 1.0
+    val = 0.1 * (float)((int)(10.0 * val + 0.5)); //quantize so that it doesn't chatter
+
+    //add code here to change the potentiometer value to something useful (like gain_dB?)
+    // ..... add code here if you'd like ......
+
+    //send the potentiometer value to your algorithm as a control parameter
+    if (abs(val - prev_val) > 0.05) { //is it different than befor?
+      Serial.print("Sending new value to my algorithms: "); Serial.println(val);
+      effect1.setUserParameter(val);   effect2.setUserParameter(val);
+    }
+    prev_val = val;  //use the value the next time around
+  } // end if
+} //end servicePotentiometer();
+
+
+void printMemoryAndCPU(unsigned long curTime_millis) {
+  static unsigned long updatePeriod_millis = 2000; //how many milliseconds between updating gain reading?
+  static unsigned long lastUpdate_millis = 0;
+
+  //has enough time passed to update everything?
+  if (curTime_millis < lastUpdate_millis) lastUpdate_millis = 0; //handle wrap-around of the clock
+  if ((curTime_millis - lastUpdate_millis) > updatePeriod_millis) { //is it time to update the user interface?
+    Serial.print("CPU: Usage, Max: ");
+    Serial.print(AudioProcessorUsage());
+    Serial.print(", ");
+    Serial.print(AudioProcessorUsageMax());
+    Serial.print("    ");
+    Serial.print("Int16 Memory: ");
+    Serial.print(AudioMemoryUsage());
+    Serial.print(", ");
+    Serial.print(AudioMemoryUsageMax());
+    Serial.print("    ");
+    Serial.print("Float Memory: ");
+    Serial.print(AudioMemoryUsage_F32());
+    Serial.print(", ");
+    Serial.print(AudioMemoryUsageMax_F32());
+    Serial.println();
+    lastUpdate_millis = curTime_millis; //we will use this value the next time around.
+  }
+}
+