Haxe RtAudio

Haxe port of RtAudio, to play sample by sample audio, for cpp target.

Works on linux (for Alsa, PulseAudio and Jack APIs).

Usage

import rtaudio.Audio;
import rtaudio.Api;
import rtaudio.Device;

class Main
{
    public static function main():Void
    {
        // API selection:
        Audio.api = Api.PulseAudio; // To use the PulseAudio api (the default mainstream audio api on linux)
        Audio.api = Api.Alsa; // To use the Alsa api
        Audio.api = Api.Jack; // To use the Jack api (the professional linux audio api)
        // If you don't set Audio.api, the default used api will be PulseAudio

        // Devices management:
        var numberOfDevices:Int = Device.count();
        var devices:Array<Device> = Device.all();

        for (device in devices)
        {
            var id:Int = device.id;
            var isUsable:Bool = device.isUsable;
            var name:String = device.name;
            var numberOfAvailableInputChannels:Int = device.inputChannels;
            var numberOfAvailableOutputChannels:Int = device.outputChannels;
            var numberOfAvailableDuplexChannels:Int = device.duplexChannels;
            var isDefaultInput:Bool = device.isDefaultInput;
            var isDefaultOutput:Bool = device.isDefaultOutput;
            var acceptedSampleRates:Array<Int> = device.sampleRates;
            var preferredSampleRate:Int = device.preferredSampleRate;
        }

        // Get a specific device by its ID
        var device:Device = Device.get(3);

        // Get default input and output device
        var inputDevice:Device = Device.defaultInput();
        var outputDevice:Device = Device.defaultOutput();

        // Set buffer size and sample rate (in Hertz)
        Audio.bufferSize = 64; // Default value: 512
        Audio.sampleRate = 44100; // Default value: 48000
        Audio.inputDevice = Device.get(0); // Default value: Device.defaultInput()
        Audio.outputDevice = Device.get(0); // Default value: Device.defaultOutput()
        Audio.inputChannels = 2; // Default value: 0
        Audio.outputChannels = 2; // Default value: 2

        // Play audio
        var time:Float = 0;
        
        Audio.start(function(inputBuffer:Array<Array<Float>>):Array<Array<Float>>
        {
            // Takes a input buffer as argument and returns an output buffer (with values between -1 and 1)
            // A buffer is a bidimensional array like buffer[sampleIndex][channelIndex]
            // For example, here it playbacks the input and it mixes it with a 440Hz sine wave:

            var outputBuffer:Array<Array<Float>> = [];

            for (sampleIndex in 0...Audio.bufferSize)
            {
                var sine = Math.sin(2 * Math.PI * time * 440);
                outputBuffer[sampleIndex] = [];

                for (channelIndex in 0...Audio.inputChannels)
                {
                    outputBuffer[sampleIndex][channelIndex] = inputBuffer[sampleIndex][channelIndex] * 0.8 + sine * 0.2;
                }

                time += 1 / 44100;
            }

            return outputBuffer;
        });

        // Stop audio playing
        Audio.stop();

        // You can check if an audio callback is currently running
        var running:Bool = Audio.started;

        // Optional: Exception handling:
        Audio.errorHandler = function(e:Dynamic):Void
        {
            trace(e);
        };
    }
}