A .NET-based DirectX Sound Capture and Recording Application

Category:

C#, VB.NET, ASP.NET

Type:

Applications

Difficulty:

Intermediate

Author: Anonymous

Version Compatibility: Visual Basic.NET

More information:

This is a sample application that was converted from Microsoft's Visual C# sample. Rewritten in VB.NET, this sample uses Dx9 to record and playback Wave files.

Instructions: Copy the declarations and code below and paste directly into your VB project.

Declarations:
Private Const NUMBER_RECORD_NOTIFICATIONS As Integer = 16 Private mbCapturing As Boolean = False Private mbInputFormatSupported(19) As Boolean Private miNotifySize As Integer = 0 Private miCaptureBufferSize As Integer = 0 Private miNextCaptureOffset As Integer = 0 Private miSampleCount As Integer = 0 Private msFilePath As String Private mbRecording As Boolean Private msFileName As String Private mthrNotifyThread As Threading.Thread Private mthrNotificationEvent As Threading.AutoResetEvent Private mbwWriter As IO.BinaryWriter Private mfsWaveFile As IO.FileStream Private maryDirectSoundFormats As New ArrayList Private mguidCaptureDevice As Guid = Guid.Empty Private mappNotify As Microsoft.DirectX.DirectSound.Notify Private mappBuffer As Microsoft.DirectX.DirectSound.CaptureBuffer Private mwvfInputFormat As Microsoft.DirectX.DirectSound.WaveFormat Private mappDevice As Microsoft.DirectX.DirectSound.Capture Private mdsPositionNotify(NUMBER_RECORD_NOTIFICATIONS + 1) As Microsoft.DirectX.DirectSound.BufferPositionNotify Private mdsCaptureDevices As New Microsoft.DirectX.DirectSound.CaptureDevicesCollection() Private Structure FormatInfo Public format As Microsoft.DirectX.DirectSound.WaveFormat Public ToString As String End Structure

Code:

Public Class Form1

Private Const NUMBER_RECORD_NOTIFICATIONS As Integer = 16

Private mbCapturing As Boolean = False
    Private mbInputFormatSupported(19) As Boolean

Private miNotifySize As Integer = 0
    Private miCaptureBufferSize As Integer = 0
    Private miNextCaptureOffset As Integer = 0
    Private miSampleCount As Integer = 0

Private msFilePath As String
    Private mbRecording As Boolean
    Private msFileName As String

Private mthrNotifyThread As Threading.Thread
    Private mthrNotificationEvent As Threading.AutoResetEvent

Private mbwWriter As IO.BinaryWriter
    Private mfsWaveFile As IO.FileStream
    Private maryDirectSoundFormats As New ArrayList
    Private mguidCaptureDevice As Guid = Guid.Empty

Private mappNotify As Microsoft.DirectX.DirectSound.Notify
    Private mappBuffer As Microsoft.DirectX.DirectSound.CaptureBuffer
    Private mwvfInputFormat As Microsoft.DirectX.DirectSound.WaveFormat
    Private mappDevice As Microsoft.DirectX.DirectSound.Capture
    Private mdsPositionNotify(NUMBER_RECORD_NOTIFICATIONS + 1) As Microsoft.DirectX.DirectSound.BufferPositionNotify
    Private mdsCaptureDevices As New Microsoft.DirectX.DirectSound.CaptureDevicesCollection()

Private Structure FormatInfo
        Public format As Microsoft.DirectX.DirectSound.WaveFormat
        Public ToString As String
    End Structure

Private Function ConvertWaveFormatToString(ByRef wvfWaveFormat As Microsoft.DirectX.DirectSound.WaveFormat) As String

'-----------------------------------------------------------------------------
        ' Name: ConvertWaveFormatToString()
        ' Desc: Converts a wave Format to a text string
        '-----------------------------------------------------------------------------
        Dim sReturn As String

On Error GoTo ErrorHandler

With wvfWaveFormat
            sReturn = .SamplesPerSecond & " Hz, " & .BitsPerSample & "-bit "

If wvfWaveFormat.Channels = 1 Then
                sReturn = sReturn & "Mono"
            Else
                sReturn = sReturn & "Stereo"
            End If
        End With

ConvertWaveFormatToString = sReturn

Exit Function

ErrorHandler:

CriticalError(Err, Me.Name, "ConvertWaveFormatToString", Me)

End Function

Private Sub StartOrStopRecord(ByVal bStartRecording As Boolean)

'-----------------------------------------------------------------------------
        ' Name: StartOrStopRecord()
        ' Desc: Starts or stops the capture buffer from mbRecording
        '-----------------------------------------------------------------------------

On Error GoTo ErrorHandler

If bStartRecording = True Then
            ' Create a capture buffer, and tell the capture 
            ' buffer to start mbRecording   
            CreateCaptureBuffer()
            mappBuffer.Start(True)
        Else
            ' Stop the buffer, and read any data that was not 
            ' caught by a notification
            mappBuffer.Stop()

RecordCapturedData()

mbwWriter.Seek(4, IO.SeekOrigin.Begin) ' Seek to the length descriptor of the RIFF file.
            mbwWriter.Write(Int(miSampleCount + 36)) ' Write the file length, minus first 8 bytes of RIFF description.
            mbwWriter.Seek(40, IO.SeekOrigin.Begin) ' Seek to the data length descriptor of the RIFF file.
            mbwWriter.Write(miSampleCount) ' Write the length of the sample data in bytes.

mbwWriter.Close()  ' Close the file now.
            mbwWriter = Nothing   ' Set the mbwWriter to null.
            mfsWaveFile = Nothing ' Set the FileStream to null.
        End If

Exit Sub

ErrorHandler:

CriticalError(Err, Me.Name, "StartOrStopRecord", Me)

End Sub
    Private Sub CreateCaptureBuffer()

'------------------------------...