Audio level meter for NAudio recording

Question

I´m recording audio to a WAV file using NAudio library. I want to be able to update a ProgressBar to the value of audio level/volume as the sample data arrives.

public WaveIn Recorder_NAudio;
public WaveFileWriter Writer_NAudio;

public void record()
{
        Recorder_NAudio = new WaveIn();
                Recorder_NAudio.WaveFormat = new NAudio.Wave.WaveFormat(sampleRate, 1);
                Writer_NAudio = new WaveFileWriter(File.Open(tempPath, FileMode.Create), Recorder_NAudio.WaveFormat);

                Recorder_NAudio.DataAvailable += new EventHandler<WaveInEventArgs>(Recorder2_DataAvailable);
                Recorder_NAudio.StartRecording();
}

void Recorder2_DataAvailable(object sender, WaveInEventArgs e)
{
     if (Writer_NAudio != null) if (Writer_NAudio.CanWrite)
     {
         Writer_NAudio.WriteData(e.Buffer, 0, e.BytesRecorded);

         // I need help to create this function
         ProgressBar1.value = GetVolumeFromBytes(e.buffer);
     }
}

Answer 1

For a Windows Forms example, have a look at the NAudioDemo source code and in particular the AudioPlaybackPanel class, which uses a MeteringSampleProvider and subscribes to its StreamVolume event to set the properties on a custom volume meter control (included in NAudio)

For a WPF example, look at voicerecorder.codeplex.com which uses a similar technique and the volume metering is described in this article.

Answer 2

I wrote a control that does everything you want to control can be found here.

For use with NAudio is sufficient to define a device as:

Private NAudio.CoreAudioApi.MMDevice device;

then at any time you know the value of the audio levels of the following values:

Master :

device.AudioMeterInformation.MasterPeakValue;

Left :

device.AudioMeterInformation.PeakValues[0];

Right :

device.AudioMeterInformation.PeakValues[1];