| Mozzi version v1.1.0 sound synthesis library for Arduino |

05.Control_Filters/Smooth/Smooth.ino

This example demonstrates the Smooth class.

/* Example of a sound changing volume with and without
smoothing of the control signal to remove obvious clicks,
using Mozzi sonification library.
Demonstrates using Smooth to filter a control signal at audio rate,
EventDelay to schedule changes and rand() to choose random volumes.
Circuit: Audio output on digital pin 9 on a Uno or similar, or
DAC/A14 on Teensy 3.1, or
your board check the README or http://sensorium.github.io/Mozzi/
Mozzi documentation/API
https://sensorium.github.io/Mozzi/doc/html/index.html
Mozzi help/discussion/announcements:
https://groups.google.com/forum/#!forum/mozzi-users
Tim Barrass 2012, CC by-nc-sa.
*/
#include <MozziGuts.h>
#include <Oscil.h> // oscillator template
#include <tables/sin2048_int8.h> // sine table for oscillator
#include <EventDelay.h>
#include <Smooth.h>
#include <mozzi_rand.h>
#define CONTROL_RATE 128
Oscil <SIN2048_NUM_CELLS, AUDIO_RATE> aSin(SIN2048_DATA);
// for scheduling audio gain changes
EventDelay kGainChangeDelay;
const unsigned int gainChangeMsec = 200;
// for scheduling turning smoothing on and off
EventDelay kSmoothOnOff;
const unsigned int smoothOnOffMsec = 2000;
float smoothness = 0.9975f;
Smooth <long> aSmoothGain(smoothness);
boolean smoothIsOn=true;
long target_gain = 0;
void setup(){
aSin.setFreq(330); // set the frequency
kGainChangeDelay.set(gainChangeMsec);
kSmoothOnOff.set(smoothOnOffMsec);
startMozzi(CONTROL_RATE);
}
void updateControl(){
// switch smoothing on and off to show the difference
if(kSmoothOnOff.ready()){
if (smoothIsOn) {
aSmoothGain.setSmoothness(0.f);
smoothIsOn = false;
}
else{
aSmoothGain.setSmoothness(smoothness);
smoothIsOn = true;
}
kSmoothOnOff.start();
}
// random volume changes
if(kGainChangeDelay.ready()){
target_gain = rand((byte) 255);
kGainChangeDelay.start();
}
}
AudioOutput_t updateAudio(){
return MonoOutput::from16Bit(aSmoothGain.next(target_gain) * aSin.next());
}
void loop(){
audioHook();
}