// Copyright (c) 2010, Peter Smith
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
// Redistributions of source code must retain the above copyright notice, this list
// of conditions and the following disclaimer.
//
// Redistributions in binary form must reproduce the above copyright notice, this
// list of conditions and the following disclaimer in the documentation and/or
// other materials provided with the distribution.
//
// Neither the name of the Author nor the names of its contributors may be used to
// endorse or promote products derived from this software without specific prior
// written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
// IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
// OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
// OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
// OF THE POSSIBILITY OF SUCH DAMAGE.
namespace AudioIN
{
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using OpenTK;
using OpenTK.Audio;
using OpenTK.Audio.OpenAL;
public class Microphone
{
#region Fields
/// <summary>
/// Boolean value indicating if microphone intialized correctly
/// </summary>
public bool isMicrophoneValid = false;
AudioCapture audio_capture;
private byte[] buffer = new byte[1024];
private bool continuePolling = false;
private Queue<byte[]> microphoneData = new Queue<byte[]>();
Thread pollMicrophone = null;
private int SampleToByte = 2;
private int src;
#endregion Fields
#region Constructors
/// <summary>
/// Initialize the microphone
/// </summary>
/// <param name="samplingRate">Sample rate used during capture</param>
/// <param name="gain">Gain of the microphone</param>
/// <param name="deviceCaptureName">Name of the Device used for capturing audio</param>
/// <param name="format">One of the openAL formats</param>
/// <param name="bufferSize">Size of the buffer</param>
public Microphone(int samplingRate, float gain, string deviceCaptureName, ALFormat format, int bufferSize)
{
isMicrophoneValid = SetUpMicrophone(samplingRate, gain, deviceCaptureName, format, bufferSize);
}
#endregion Constructors
#region Properties
/// <summary>
/// Queue used to hold the incoming data from the microphone.
/// </summary>
public Queue<byte[]> MicrophoneData
{
get
{
return microphoneData;
}
set
{
microphoneData = value;
}
}
#endregion Properties
#region Methods
/// <summary>
/// Start recording from the Microphone
/// </summary>
public void StartRecording()
{
if (isMicrophoneValid == true)
{
audio_capture.Start();
continuePolling = true;
if (pollMicrophone == null ||pollMicrophone.IsAlive == false)
{
pollMicrophone = new Thread(PollMicrophoneForData);
pollMicrophone.Start();
}
}
}
/// <summary>
/// Stop recording from the Microphone
/// </summary>
public void StopRecording()
{
if (isMicrophoneValid == true)
{
continuePolling = false;
audio_capture.Stop();
ClearBuffers(0);
MicrophoneData.Clear();
}
}
/// <summary>
/// Clears the Microphone buffers
/// </summary>
/// <param name="input">Which buffer</param>
private void ClearBuffers(int input)
{
int[] freedbuffers;
if (input == 0)
{
int BuffersProcessed;
AL.GetSource(src, ALGetSourcei.BuffersProcessed, out BuffersProcessed);
if (BuffersProcessed == 0)
return;
freedbuffers = AL.SourceUnqueueBuffers(src, BuffersProcessed);
}
else
{
freedbuffers = AL.SourceUnqueueBuffers(src, input);
}
AL.DeleteBuffers(freedbuffers);
}
private bool InitializeMicrophone(int samplingRate, float gain, string deviceCaptureName, ALFormat format, int bufferSize)
{
AL.Listener(ALListenerf.Gain, gain);
src = AL.GenSource();
SampleToByte = NumberOfBytesPerSample(format);
buffer = new byte[bufferSize];
try
{
audio_capture = new AudioCapture(deviceCaptureName, samplingRate, format, bufferSize);
}
catch (AudioDeviceException ade)
{
audio_capture = null;
}
if (audio_capture == null)
return false;
return true;
}
private int NumberOfBytesPerSample(ALFormat format)
{
int bytesPerSample = 2;
switch (format)
{
case ALFormat.Mono16:
bytesPerSample = 2;
break;
case ALFormat.Mono8:
bytesPerSample = 1;
break;
case ALFormat.MonoALawExt:
bytesPerSample = 1;
break;
case ALFormat.MonoDoubleExt:
bytesPerSample = 8;
break;
case ALFormat.MonoFloat32Ext:
bytesPerSample = 4;
break;
case ALFormat.MonoIma4Ext:
bytesPerSample = 4;
break;
case ALFormat.MonoMuLawExt:
bytesPerSample = 1;
break;
case ALFormat.Mp3Ext:
bytesPerSample = 2; //Guessed might not be correct
break;
case ALFormat.Multi51Chn16Ext:
bytesPerSample = 6 * 2;
break;
case ALFormat.Multi51Chn32Ext:
bytesPerSample = 6 * 4;
break;
case ALFormat.Multi51Chn8Ext:
bytesPerSample = 6 * 1;
break;
case ALFormat.Multi61Chn16Ext:
bytesPerSample = 7 * 2;
break;
case ALFormat.Multi61Chn32Ext:
bytesPerSample = 7 * 4;
break;
case ALFormat.Multi61Chn8Ext:
bytesPerSample = 7 * 1;
break;
case ALFormat.Multi71Chn16Ext:
bytesPerSample = 7 * 2;
break;
case ALFormat.Multi71Chn32Ext:
bytesPerSample = 7 * 4;
break;
case ALFormat.Multi71Chn8Ext:
bytesPerSample = 7 * 1;
break;
case ALFormat.MultiQuad16Ext:
bytesPerSample = 4 * 2;
break;
case ALFormat.MultiQuad32Ext:
bytesPerSample = 4 * 4;
break;
case ALFormat.MultiQuad8Ext:
bytesPerSample = 4 * 1;
break;
case ALFormat.MultiRear16Ext:
bytesPerSample = 1 * 2;
break;
case ALFormat.MultiRear32Ext:
bytesPerSample = 1 * 4;
break;
case ALFormat.MultiRear8Ext:
bytesPerSample = 1 * 1;
break;
case ALFormat.Stereo16:
bytesPerSample = 2 * 2;
break;
case ALFormat.Stereo8:
bytesPerSample = 2 * 1;
break;
case ALFormat.StereoALawExt:
bytesPerSample = 2 * 1;
break;
case ALFormat.StereoDoubleExt:
bytesPerSample = 2 * 8;
break;
case ALFormat.StereoFloat32Ext:
bytesPerSample = 2 * 4;
break;
case ALFormat.StereoIma4Ext:
bytesPerSample = 1; //Guessed
break;
case ALFormat.StereoMuLawExt:
bytesPerSample = 2 * 1;
break;
case ALFormat.VorbisExt:
bytesPerSample = 2; //Guessed
break;
default:
break;
}
return bytesPerSample;
}
/// <summary>
/// Used to poll the Microphone for data
/// </summary>
private void PollMicrophoneForData()
{
while (continuePolling)
{
Thread.Sleep(1); //Allow GUI some time
if (audio_capture.AvailableSamples * SampleToByte >= buffer.Length)
{
UpdateSamples();
}
}
}
private bool SetUpMicrophone(int samplingRate, float gain, string deviceCaptureName, ALFormat format, int bufferSize)
{
//return InitializeMicrophone(8000, 4.0f, AudioCapture.DefaultDevice, ALFormat.Mono16, 1024, codec);
return InitializeMicrophone(samplingRate, gain, deviceCaptureName, format, bufferSize);
}
private void UpdateSamples()
{
buffer = new byte[buffer.Length];
audio_capture.ReadSamples(buffer, buffer.Length / SampleToByte); //Need to divide as the readsamples expects the value to be in 2 bytes.
//Queue raw data, let receiving application determine if it needs to compress
this.microphoneData.Enqueue(buffer);
ClearBuffers(0);
}
#endregion Methods
}
}
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