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Я играю синусоидальную волну на частоте 1 кГц, созданную классом, который реализует NAudio IWaveProvider. Хотя я изменяю амплитуду синусоидальной волны на разных уровнях, WaveOut всегда воспроизводится на максимальной громкости. Вот это vb.net код:

 Public Class Audio

    Public MustInherit Class WaveProvider32
        Implements Wave.IWaveProvider

        Private _waveFormat As NAudio.Wave.WaveFormat
        Public Sub New()
            Me.New(44100, 1)
        End Sub

        Public Sub New(ByVal sampleRate As Integer, ByVal channels As Integer)
            MyBase.New
            Me.SetWaveFormat(sampleRate, channels)
        End Sub

        Public Sub SetWaveFormat(ByVal sampleRate As Integer, ByVal channels As Integer)
            _waveFormat = WaveFormat.CreateIeeeFloatWaveFormat(sampleRate, channels)
        End Sub

        Public Overloads Function Read(ByVal buffer() As Byte, ByVal offset As Integer, ByVal count As Integer) As Integer
            Dim waveBuffer As WaveBuffer = New WaveBuffer(buffer)
            Dim samplesRequired As Integer = count / 4
            Dim samplesRead As Integer = Me.Read(waveBuffer.FloatBuffer, offset / 4, samplesRequired)
            Return samplesRead * 4
        End Function

        Public MustOverride Overloads Function Read(ByVal buffer() As Single, ByVal offset As Integer, ByVal sampleCount As Integer) As Integer
        Public MustOverride Function IWaveProvider_Read(buffer() As Byte, offset As Integer, count As Integer) As Integer Implements Wave.IWaveProvider.Read

        Public ReadOnly Property WaveFormat As WaveFormat
            Get
                Return _waveFormat
            End Get
        End Property

        Public MustOverride ReadOnly Property IWaveProvider_WaveFormat As Wave.WaveFormat Implements Wave.IWaveProvider.WaveFormat

    End Class

    Public Class SineWaveProvider32Ex
        Inherits WaveProvider32

        Shadows waveFormat As WaveFormat

        Private m_fAmplitude As Single

        Private m_fFrequency As Single

        Private m_nSample As Integer

        Private m_bitPerSample As Integer

        Private m_waveFileWriter As WaveFileWriter

        Public Sub New(ByVal waveFileWriter As WaveFileWriter, ByVal sampleRate As Integer, ByVal channels As Integer, ByVal Amplitude As Single, ByVal Frequency As Single, ByVal BitPerSample As Integer)
            MyBase.New
            Me.m_waveFileWriter = waveFileWriter
            Me.m_fAmplitude = Amplitude
            Me.m_fFrequency = Frequency
            Me.m_bitPerSample = BitPerSample
            SetWaveFormat(sampleRate, channels, BitPerSample)
        End Sub

        Public Property Frequency As Single
            Get
                Return Frequency
            End Get
            Set
                m_fFrequency = Value
            End Set
        End Property

        Public Property Amplitude As Single
            Get
                Return Amplitude
            End Get
            Set
                m_fAmplitude = Value
            End Set
        End Property

        Public Overrides ReadOnly Property IWaveProvider_WaveFormat As WaveFormat
            Get
                Return waveFormat
            End Get
        End Property

        Public Overrides Function Read(buffer() As Single, offset As Integer, sampleCount As Integer) As Integer
            Dim sampleRate As Integer = waveFormat.SampleRate
            Dim n As Integer = 0
            Do While (n < sampleCount)
                buffer(n   offset) = CType(m_fAmplitude * Math.Sin(2 _
                            * (Math.PI _
                            * (m_nSample * m_fFrequency)) _
                            / sampleRate), Single)
                If m_fFrequency = 0 Then
                    If m_fAmplitude = 1.0! Then
                        m_fAmplitude = 0.9999999!
                    ElseIf m_fAmplitude = -1.0! Then
                        m_fAmplitude = -0.9999999!
                    End If
                    buffer(n   offset) = CType(m_fAmplitude, Single)
                End If
                m_nSample = (m_nSample   1)
                If (m_nSample >= sampleRate) Then
                    m_nSample = 0
                End If
                If m_waveFileWriter IsNot Nothing Then
                    m_waveFileWriter.WriteSample(buffer((n   offset)))
                End If
                n = (n   1)
            Loop
            Return sampleCount
        End Function

        Public Overrides Function IWaveProvider_Read(buffer() As Byte, offset As Integer, count As Integer) As Integer
            Dim waveBuffer As WaveBuffer = New WaveBuffer(buffer)
            Dim samplesRequired As Integer = (count / 4)
            Dim samplesRead As Integer = Read(waveBuffer.FloatBuffer, (offset / 4), samplesRequired)
            Return (samplesRead * 4)
        End Function

        Public Overloads Sub SetWaveFormat(ByVal sampleRate As Integer, ByVal channels As Integer, BitPerSample As Integer)
            Me.waveFormat = New WaveFormat(sampleRate, BitPerSample, channels)
        End Sub

    End Class

End Class
 

 Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click

        Dim tempFile As String = "C:TempTest.wav"
        Dim input As Audio.SineWaveProvider32Ex

        If (waveOut Is Nothing) Then
            MyWaveFileWriter = New WaveFileWriter(tempFile, New WaveFormat(192000, 24, 2))
            input = New Audio.SineWaveProvider32Ex(MyWaveFileWriter, 192000, 2, 1.0! / (Math.Pow(2, 2)), 1000.0!, 24)
            waveOut = New WaveOut
            waveOut.Init(input)
            waveOut.Play()
        Else
            waveOut.Stop()
            waveOut.Dispose()
            waveOut = Nothing
            MyWaveFileWriter.Close()
        End If

    End Sub
 

Я изменяю свойство амплитуды с 1.0! / (Математическое значение(2, 0)) на 1.0! / (Математическое значение(2, 23)), но ничего не меняется, всегда максимальная громкость.
Любопытно, что если я воспроизведу сохраненный wav-файл (который был записан с правильной амплитудой) с помощью WaveFileReader, выходной звук будет отображаться с правильной амплитудой.

Кто-нибудь может помочь?

Спасибо