Audio Engine

Audio Engine is a C++ library created for the processing and generation of digital audio signals.

The library is based on the OOP paradigm, using a super class called AudioEngine from which all the other sub classes inherit to generate the signals.

The generators currently available are:

PureTone
PulseTone
WarbleTone
Noise: white, pink and NBN.

USAGE:

As a practical example, the following script shows how to generate and print a pure tone on the console:

#include "PureTone.h"

int main() {

    //Generator parameters:
    int sampleRate = 48000;
    int buffer = 256;
    float freq = 1000.0;
    ChannelType channel = ChannelType::Left; //Or: ChannelType::Right , ChannelType::Stereo
    float gain = 0.0; //In dBFS
    float* data;

    //Instantiate the class:
    PureTone tone(sampleRate, buffer);

    tone.setGain(gain);
    tone.setFreq(freq);

    //Flag to enable signal generation:
    tone.signalEmissionEnabled();

    //Start a loop to generate 100 iterations:
    for (int i = 0; i < 100; i++) {
        //Generate the signal
        tone.genSignal();
        data = tone.getData();

        //Print the values in console:
        for (int t = 0; t < buffer*2; ++i) { //The buffer*2 is because it is considered to be stereo.
            printf("%f\n", data[t]);
        }
    }

    //Flag to stop signal generation:
    tone.stopEmission();

    //Start a loop so that the tone gradually lowers its gain to avoid popping:
    while (tone.isBypassed()) {
        //Generate the signal
        tone.genSignal();
        data = tone.getData();

        //Print the values in console:
        for (int t = 0; t < buffer*2; ++i) {
            printf("%f\n", data[t]);
        }
   }

   //Release memory:
   tone.freeBuffer();
   delete[] data;

    return 0;
}

While this example is only for the pure tone, it works much the same for the other generators. They are all instantiated with the sampleRate and buffer variables and then their other parameters are set accordingly.

BUILDING:

CMake is used to create and compile this library. In case you are using Linux, the commands to compile them are the following:

$ mkdir build
$ cd build
$ cmake ..
$ cmake --build .

On Windows:

$ mkdir build
$ cd build
$ cmake ..
$ cmake --build . --config Release

In this case the compiled version of the AudioEngine.lib library will be created inside the Release folder, so it is necessary to copy that file and move it one directory back. That is, from './audio-engine/build/Release/' to './audio-engine/build'.

TESTING:

The test suite for this library is written in Python. For this, it is necessary to generate a wrapper from the library in C++ to Python. This wrapper is done with the pybind11 library.

To compile the wrapper we must first clone the library to our repository:

$ cd ./test
$ git clone https://github.com/pybind/pybind11.git

Once the library is cloned and inside the test directory, the wrapper must be compiled.

This is done in the same way as before, if you are on Linux:

$ mkdir build
$ cd build
$ cmake ..
$ cmake --build .

On Windows:

$ mkdir build
$ cd build
$ cmake ..
$ cmake --build . --config Release

As in the previous case, in Windows the files must be copied from the Release folder to build. That is, move them from './audio-engine/test/build/Release/' to './audio-engine/test/build'.

Once the wrapper is compiled, from the './audio-engine/test' directory you have to execute the following command to run the tests:

$ python test.py

maxiaortiz22/audio-engine

Audio Engine

USAGE:

BUILDING:

TESTING: