Introduction

Simple library for audio wavetable synthesis programming in Arduino IDE. waveTableOsc is based on the wonderful articles by Nigel Redmon about the subject. You can read it in https://www.earlevel.com/main/2012/05/03/a-wavetable-oscillator%e2%80%94introduction/

Currently there are only one class, waveTableOsc, with two public member functions, including the constructor: waveTableOsc(int,int,cons char*,float) and phasor(double);

This library is still under development, feel free to point out issues and suggestions.

Brief explanation

Wavetable synthesis is the technique of sequentially outputting sample values indexed in an array at a specific audio sample rate.

Class waveTableOsc

Member Functions

waveTableOsc (CONSTRUCTOR)

Create and initializes a waveTableOsc instance

• Syntax
  waveTableOsc(int table_size, int sample_rate, const char* function_select, float amplitude);

• Parameters

0. int table_size The length of the array storing the Wave Function.
1. int sample_rate The Sample Rate of the context the function will be used.
2. const char* function_select String to define the Wave Function. Valid values are: "sine","saw","square".
3. float amplitude The amplitude of the Wave Function stored in the array.

• Returns

  void

Phasor

• Synthax
  phasor(double frequency);

• Parameters

0. double frequency The wave frequency that the wavetableOsc object will output. This method returns an int sample value corresponding to the current phase of the phasor object.

• Returns

  int

Installation

Add the source files to your Arduino library folders and include the library with a #include "waveTableOsc.h" statement in the begging of your code.

Usage Example

// includes library
#include "waveTableOsc.h"

//creates variables for storing the parameters of waveTableOsc object to be created
int waveSize = 512;
int sampleRate = 44100;
int amp = 8192;
float freq;

//creates a waveTableOsc type variable 
waveTableOsc osc(waveSize, sampleRate, "saw", amp); //tableSize,SampleRate,Function(String),Amplitude);

void setup() {
//initialize frequency variable
freq = 440;
}

void loop() {
//this method should be called inside some kind of "render audio" function
osc.phasor(freq);

}