RemoveStream Method (WMMutualExclusion)

Imports Leadtools
Imports Leadtools.Multimedia
Imports LeadtoolsMultimediaExamples.Fixtures

Public _result As Boolean = False
Public _form As ConvertCtrlForm = New ConvertCtrlForm()
Private Const CODEC_AUDIO_MSAUDIO As Integer = 353 ' Microsoft WMAudio
Private Const CODEC_VIDEO_WMV1 As Integer = 827739479 ' FOURCC( "W"c, "M"c, "V"c, "1"c )

Public Sub AddStreamExample()
   Dim convertctrl As ConvertCtrl = _form.ConvertCtrl
   Dim inFile As String = Path.Combine(LEAD_VARS.MediaDir, "ConvertCtrl_Source.avi")
   Dim outFile As String = Path.Combine(LEAD_VARS.MediaDir, "WMProfile_RemoveStreamExample.avi")

   Try
      Dim manager As WMProfileManager = New WMProfileManager()

      ' create a WMProfile
      convertctrl.WMProfile = CreateCustomProfile(manager)

      ' run the conversion
      convertctrl.SourceFile = inFile
      convertctrl.TargetFormat = TargetFormatType.WMV
      convertctrl.TargetFile = outFile
      convertctrl.StartConvert()

      ' dispose of the manager
      manager.Dispose()
   Catch e1 As Exception
      _result = False
   End Try

   ' 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.
   Do While convertctrl.State = ConvertState.Running
      Application.DoEvents()
   Loop

   ' check the validity of the output file
   Dim mediaInfo As MediaInfo = New MediaInfo()
   Try
      mediaInfo.SourceFile = outFile
      If (mediaInfo.SourceFormat = SourceFormatType.WMV) Then _result = True
   Catch e2 As Exception
      _result = False
   End Try
End Sub

Private Function CreateCustomProfile(ByVal manager As WMProfileManager) As WMProfile
   Dim profile As WMProfile = manager.CreateEmptyProfile(WMT_Version.V9)
   profile.Name = "Custom Profile"
   profile.Description = "Custom Profile Description"

   Dim added As Boolean = AddAudioStream(manager, profile, 1, CODEC_AUDIO_MSAUDIO, 8000, 8000, 1, True)

   ' add 5 video streams with bitrates starting from 32KB/s (256Kbps). Increase the bitrate if you increase the video size
   Dim i As Integer = 0
   Do While (i <= 4)
      AddVideoStream(manager, profile, (2 + i), CODEC_VIDEO_WMV1, (1024 * 32) + i * 1024, 400, 300, 5 * (i + 1), 0, 8)
      i += 1
   Loop

   '  mark all the video streams for mutual exclusion
   AddMutexObject(profile, 2, 5)
   Return profile
End Function

Private Function AddVideoStream(ByVal manager As WMProfileManager, _
                                 ByVal profile As WMProfile, _
                                 ByVal streamnum As Integer, _
                                 ByVal fourcc As Long, _
                                 ByVal bitrate As Integer, _
                                 ByVal width As Integer, _
                                 ByVal height As Integer, _
                                 ByVal fps As Integer, _
                                 ByVal quality As Integer, _
                                 ByVal secperkey As Integer) As Boolean
   Dim codecformat As WMStreamConfig
   Dim mediatype As MediaType
   Dim vih As VideoInfoHeader
   Dim candidate As Boolean = False
   Dim candidatevih As VideoInfoHeader = New VideoInfoHeader()
   Dim candidatemt As MediaType = Nothing
   Dim candidatestream As WMStreamConfig = Nothing
   Dim added As Boolean = False
   Dim viharr As Byte() = New Byte(87) {}
   Dim codecs As Integer = manager.GetCodecInfoCount(Leadtools.Multimedia.Constants.MEDIATYPE_Video)
   Dim sinfo As String = String.Empty

   ' width and height must be even
   If ((width And 1) <> 0) Then width += 1
   If ((height And 1) <> 0) Then height += 1

   '  search for matching codec until I find a candidate
   Dim codecindex As Integer = 0
   Do While (codecindex < codecs) And Not candidate
      sinfo &= manager.GetCodecName(Leadtools.Multimedia.Constants.MEDIATYPE_Video, codecindex)
      Dim formats As Integer = manager.GetCodecFormatCount(Leadtools.Multimedia.Constants.MEDIATYPE_Video, codecindex)

      Dim formatindex As Integer = 0
      Do While formatindex < formats
         sinfo &= manager.GetCodecFormatDesc(Leadtools.Multimedia.Constants.MEDIATYPE_Video, codecindex, formatindex)
         codecformat = manager.GetCodecFormat(Leadtools.Multimedia.Constants.MEDIATYPE_Video, codecindex, formatindex)
         mediatype = codecformat.GetMediaType()

         If mediatype.FormatType = Leadtools.Multimedia.Constants.FORMAT_VideoInfo Then
            vih = mediatype.GetVideoFormatData()
            If vih.bmiHeader.biCompression = fourcc Then
               candidate = True
               candidatevih = vih
               candidatemt = mediatype
               candidatestream = codecformat
               ' stop searching if I found a candidate
               Exit Do
            End If
         End If
         formatindex += 1
      Loop
      codecindex += 1
   Loop
   If candidate Then
      '  modify the selected codec to support this bitrate and size
      candidatevih.dwBitRate = bitrate
      candidatevih.rcSource.Right = width
      candidatevih.rcSource.Bottom = height
      candidatevih.rcTarget.Right = width
      candidatevih.rcTarget.Bottom = height
      candidatevih.bmiHeader.biWidth = width
      candidatevih.bmiHeader.biHeight = height
      ' since fps is integer, 10000000/fps always fits in a 32-bit value, so lowpart=10000000/fps and high part is always 0
      candidatevih.AvgTimePerFrame.lowpart = CInt(10000000 / fps)
      candidatevih.AvgTimePerFrame.highpart = 0

      StructToByteArray(candidatevih, viharr)

      ' candidatevih is a copy of the media type, so updating candidatevih is not enough to update the media type.
      ' Call SetVideoFormatData to copy the updated information from candidatevih to the video format data inside candidatemt
      ' If you just change candidatevih without calling candidatemt.SetVideoFormatData, 
      ' candidatemt is an empty media type with no width and height
      candidatemt.SetVideoFormatData(candidatevih, Nothing, 0)

      candidatestream.Quality = quality
      candidatestream.MaxKeyFrameSpacing = secperkey
      candidatestream.StreamNumber = streamnum
      candidatestream.StreamName = "Video Stream"
      candidatestream.ConnectionName = "Video"
      candidatestream.Bitrate = bitrate
      candidatestream.SetMediaType(candidatemt)
      profile.AddStream(candidatestream)
      added = True
   End If
   Return added
End Function

Private Function AddAudioStream(ByVal manager As WMProfileManager, _
                                 ByVal profile As WMProfile, _
                                 ByVal streamnum As Integer, _
                                 ByVal formattag As Integer, _
                                 ByVal prefbitrate As Integer, _
                                 ByVal samplespersec As Integer, _
                                 ByVal channels As Integer, _
                                 ByVal withvideo As Boolean) As Boolean
   Dim codecformat As WMStreamConfig
   Dim mediatype As MediaType
   Dim wfex As WaveFormatEx = New WaveFormatEx()
   Dim added As Boolean = False
   Dim candidate As Boolean = False
   Dim candidatewfex As WaveFormatEx = New WaveFormatEx()
   Dim candidatemt As MediaType = Nothing
   Dim mt As MediaType
   Dim stream As WMStreamConfig
   Dim codecs As Integer = manager.GetCodecInfoCount(Leadtools.Multimedia.Constants.MEDIATYPE_Audio)

   '  search for matching codec
   Dim codecindex As Integer = 0
   Do While codecindex < codecs
      Dim formats As Integer = manager.GetCodecFormatCount(Leadtools.Multimedia.Constants.MEDIATYPE_Audio, codecindex)
      Dim formatindex As Integer = 0
      Do While formatindex < formats
         codecformat = manager.GetCodecFormat(Leadtools.Multimedia.Constants.MEDIATYPE_Audio, codecindex, formatindex)
         mediatype = codecformat.GetMediaType()
         If mediatype.FormatType = Leadtools.Multimedia.Constants.FORMAT_WaveFormatEx Then
            ByteArrayToStruct(mediatype.Format, wfex)

            Dim diff As Integer = ((wfex.nAvgBytesPerSec * 8) - prefbitrate)
            If diff < 250 AndAlso diff > -250 AndAlso wfex.nSamplesPerSec = samplespersec _
               AndAlso wfex.nChannels = channels AndAlso wfex.wFormatTag = formattag Then
               If candidate Then
                  If withvideo Then
                     ' 
                     '  For audio/video configurations, we want to
                     '  find the smaller blockalign. In this case, 
                     '  the blockalign is larger, so we want to
                     '  use the old format. 
                     If wfex.nBlockAlign <= candidatewfex.nBlockAlign Then
                        candidatewfex = wfex
                        candidatemt = mediatype
                     End If
                  ElseIf wfex.nBlockAlign >= candidatewfex.nBlockAlign Then
                     candidatewfex = wfex
                     candidatemt = mediatype
                  End If
               Else
                  candidate = True
                  candidatewfex = wfex
                  candidatemt = mediatype
               End If
            End If
         End If
         formatindex += 1
      Loop
      codecindex += 1
   Loop

   If candidate Then
      '  modify the selected codec to support this bitrate and format
      mt = New MediaType()
      mt.Type = Leadtools.Multimedia.Constants.MEDIATYPE_Audio
      mt.SubType = "{" & String.Format("{0:X8}", formattag) & "-0000-0010-8000-00AA00389B71}"
      mt.FixedSizeSamples = True
      mt.TemporalCompression = False
      mt.SampleSize = candidatewfex.nBlockAlign
      mt.FormatType = Leadtools.Multimedia.Constants.FORMAT_WaveFormatEx
      mt.SetFormatData(-1, candidatemt.Format)
      stream = profile.CreateNewStream(Leadtools.Multimedia.Constants.MEDIATYPE_Audio)
      stream.StreamNumber = streamnum
      stream.StreamName = "Audio Stream"
      stream.ConnectionName = "Audio"
      stream.Bitrate = (candidatewfex.nAvgBytesPerSec * 8)
      stream.SetMediaType(mt)
      profile.AddStream(stream)
      profile.ReconfigStream(stream)
      added = True
   End If

   Return added
End Function

Private Sub StructToByteArray(ByVal o As Object, ByRef dest As Byte())
   Try
      'convert the structure to a byte array
      Dim rawSize As Integer = Marshal.SizeOf(o)
      Dim handle As GCHandle = New GCHandle()
      Dim buffer As IntPtr

      handle = GCHandle.Alloc(dest, GCHandleType.Pinned)
      buffer = handle.AddrOfPinnedObject()
      Marshal.StructureToPtr(o, buffer, False)
      handle.Free()
   Catch ex As Exception
      Throw ex
   End Try
End Sub

Private Sub ByteArrayToStruct(ByVal buffer As Object, ByRef vih As WaveFormatEx)
   Try
      Dim handle As GCHandle = New GCHandle()

      'convert the structure to a byte array
      handle = GCHandle.Alloc(buffer, GCHandleType.Pinned)
      Dim ptr As IntPtr = handle.AddrOfPinnedObject()
      vih = CType(Marshal.PtrToStructure(ptr, GetType(WaveFormatEx)), WaveFormatEx)
      handle.Free()
   Catch ex As Exception
      Throw ex
   End Try
End Sub

Private Function AddMutexObject(ByVal profile As WMProfile, _
                                 ByVal basestream As Integer, _
                                 ByVal streamcount As Integer) As Boolean
   Dim excl As WMMutualExclusion = profile.CreateNewMutualExclusion()

   '  indicate that the streams differ by bit rate
   excl.Type = "{D6E22A01-35DA-11D1-9034-00A0C90349BE}"
   Dim i As Integer = 0
   Do While i < streamcount
      excl.AddStream(basestream + i)
      i += 1
   Loop

   '  assign the exclusion object to the profile
   profile.AddMutualExclusion(excl)
   Return True
End Function

Private Function RemoveMutexObject(ByVal profile As WMProfile, _
                                    ByVal excl As WMMutualExclusion, _
                                    ByVal basestream As Integer, _
                                    ByVal streamcount As Integer) As Boolean
   '  indicate that the streams differ by bit rate
   excl.Type = "{D6E22A01-35DA-11D1-9034-00A0C90349BE}"
   Dim i As Integer = 0
   Do While i < streamcount
      excl.RemoveStream(basestream + i)
      i += 1
   Loop

   '  remove the exclusion object from the profile
   profile.RemoveMutualExclusion(excl)
   Return True
End Function

Public NotInheritable Class LEAD_VARS
Public Const MediaDir As String = "C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 19\Media"
End Class