SetAudioType Method

Imports Leadtools 
Imports Leadtools.MediaFoundation 
Imports LeadtoolsMediaFoundationExamples.Fixtures 
 
Public _result As Boolean = False 
Public _form As New CaptureCtrlForm() 
 
Public Sub AudioTypesExample() 
   ' reference the capture control 
   Dim capturectrl As CaptureCtrl = _form.CaptureCtrl 
 
   Try 
      ' set an audio device first, you should use your audio device name here 
      If capturectrl.AudioDevices("USB") Is Nothing Then 
         Throw New Exception("No USB audio device available") 
      End If 
 
      capturectrl.AudioDevices("USB").Selected = True 
 
      ' reference the target formats collection 
      Dim formats As TargetFormats = capturectrl.TargetFormats 
 
      ' reference the target format object 
      Dim tf As TargetFormat = formats(TargetFormatType.WMV) 
 
      ' reference the target audio formats object 
      Dim taformats As TargetAudioFormats = tf.AudioFormats 
 
      ' check the index using a name string 
      Dim i As Integer = taformats.IndexOf("{00000161-0000-0010-8000-00AA00389B71}") ' Windows Media Audio (WMA) 
 
      ' get target audio format object 
      Dim taf As TargetAudioFormat = taformats(i) 
 
      ' make sure the target audio format object's name equals {00000161-0000-0010-8000-00AA00389B71} 
      If taf.Name = "{00000161-0000-0010-8000-00AA00389B71}" Then 
         ' get target audio format friendly name, use it for view propose. 
         Dim friendlyname As String = taf.FriendlyName 
      Else 
         Throw New Exception() 
      End If 
 
      ' select it 
      taf.Selected = True 
 
      ' get target audio types collection 
      Dim targetaudiotypes As TargetAudioTypes = taf.AudioTypes 
 
      ' if target audio types larger than 0, loop through all of them 
      If targetaudiotypes.Count > 0 Then 
         ' enumerate through the list of audio types 
         ' demonstrating the target audio types properties 
         For Each targetaudiotype As TargetAudioType In targetaudiotypes 
            ' get name of the target type. 
            Dim name As String = targetaudiotype.Name 
 
            ' get friendly name of the target type. 
            Dim friendlyname As String = targetaudiotype.FriendlyName 
 
            ' set the audio type into the target format if: 
            ' AudioAvgBytesPerSecond == 24000 (192 kbps) 
            ' AudioBitsPerSample == 16 
            ' AudioNumChannels == 2 (stereo) 
            ' AudioSamplesPerSecond == 44100 Hz 
            If targetaudiotype.AudioAvgBytesPerSecond = 24000 AndAlso 
               targetaudiotype.AudioBitsPerSample = 16 AndAlso 
               targetaudiotype.AudioNumChannels = 2 AndAlso 
               targetaudiotype.AudioSamplesPerSecond = 44100 Then 
               tf.SetAudioType(targetaudiotype) 
               Exit For 
            End If 
         Next 
      End If 
 
      ' check if we have can capture video and audio 
      If capturectrl.IsModeAvailable(CaptureMode.VideoAndAudio) Then 
         ' start the capture process 
         capturectrl.StartCapture(CaptureMode.VideoAndAudio) 
 
         ' we'll loop on the state and pump messages for this example. 
         ' but you should not need to if running from a Windows Forms application. 
         While capturectrl.State = CaptureState.Running 
            Application.DoEvents() 
         End While 
      End If 
 
      _result = True 
   Catch generatedExceptionName As Exception 
      _result = False 
   End Try 
End Sub