MarkSelectionStart Method

Imports Leadtools
Imports Leadtools.MediaFoundation
Imports LeadtoolsMediaFoundationExamples.Fixtures

Public _result As Boolean = False
Public _form As PlayCtrlForm = New PlayCtrlForm()
Public _playctrl As PlayCtrl
Public _seekingCaps As PlaySeeking
Public _start As TimeSpan = TimeSpan.Zero
Public Sub HasDialogExample()
   ' reference the play control
   _playctrl = _form.PlayCtrl

   ' input file for playback
   Dim inFile As String = Path.Combine(LEAD_VARS.MediaDir, "PlayCtrl_Source.avi")

   Try
      ' turn off autostart and auto rewind
      _playctrl.AutoStart = False
      _playctrl.AutoRewind = False

      ' set the source file
      _playctrl.SourceFile = inFile

      ' show some media info if available
      ShowMediaInfo()

      ' the HasDialog method tells us that the control
      ' can display the desired settings dialog.
      ' check to see if the selected video processor properties dialog is available
      If _playctrl.HasDialog(PlayDlg.SelVideoProcessor) Then
         ' now show it to change some settings
         _playctrl.ShowDialog(PlayDlg.SelVideoProcessor, _form)
         _result = True
      End If

      ' get the source object type
      Dim sot As SourceObjectType = _playctrl.SourceType

      ' check some audio properties
      Dim mute As Boolean = _playctrl.Mute
      Dim bal As Integer = _playctrl.Balance
      Dim vol As Integer = _playctrl.Volume

      ' seeking caps - you can use these to enable menu states or toolbar buttons
      _seekingCaps = _playctrl.CheckSeekingCapabilities(PlaySeeking.Forward Or PlaySeeking.Backward)

      ' subscribe to the key press event to demo play functions
      AddHandler _playctrl.KeyPress, AddressOf PlayCtrl_KeyPress

      ' start the capture process
      _playctrl.Run()

      ' 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 _playctrl.State = PlayState.Running _
           OrElse _playctrl.State = PlayState.Paused _
           OrElse _playctrl.State = PlayState.NotReady
         Application.DoEvents()
      Loop

      ' call reset source here to release resources
      ' but not necessary if we are just exiting
      _playctrl.ResetSource()
   Catch e1 As Exception
      _result = False
   End Try
End Sub

' state variables for helper timer states
Public _markedSelStart As Boolean = False
Public _markedSelEnd As Boolean = False
Public _seekedSelStart As Boolean = False
Public _seekedSelEnd As Boolean = False

' key press event handler to manage playback functions
Private Sub PlayCtrl_KeyPress(ByVal sender As Object, ByVal e As Leadtools.MediaFoundation.KeyPressEventArgs)
   Dim key As Char = CChar(ChrW(e.keyAscii))
   Select Case key
      Case "b"c
         If (Not _markedSelStart) Then
            _markedSelStart = True
            _playctrl.MarkSelectionStart()
            System.Diagnostics.Debug.WriteLine("Mark Selection Start: " & _playctrl.SelectionStart.ToString() & " secs")
            System.Diagnostics.Debug.WriteLine("  ... playctrl.State: " & _playctrl.State.ToString())
         End If
      Case "e"c
         If (Not _markedSelEnd) Then
            _markedSelEnd = True
            _playctrl.Pause()
            _playctrl.MarkSelectionEnd()
            System.Diagnostics.Debug.WriteLine("Mark Selection End: " & _playctrl.SelectionEnd.ToString() & " secs")
            System.Diagnostics.Debug.WriteLine("  ... playctrl.State: " & _playctrl.State.ToString())
            _playctrl.SeekSelectionStart()
            _playctrl.Run()
         End If
      Case "s"c
         If (Not _seekedSelStart) Then
            _seekedSelStart = True
            System.Diagnostics.Debug.WriteLine("Seek To Selection Start: " & _playctrl.SelectionStart.ToString() & " secs")
            System.Diagnostics.Debug.WriteLine("  ... playctrl.State: " & _playctrl.State.ToString())
            _playctrl.SeekSelectionStart()
         End If
      Case "f"c
         ' toggle full screen
         _playctrl.ToggleFullScreenMode()
      Case "+"c
         If _playctrl.State = PlayState.Running Then
            _playctrl.Pause()
         End If

         _playctrl.NextFrame()
      Case "-"c
         If _playctrl.State = PlayState.Running Then
            _playctrl.Pause()
         End If

         _playctrl.PreviousFrame()
      Case "z"c
         If (Not _seekedSelEnd) Then
            ' turn off full screen mode
            _playctrl.FullScreenMode = False

            _seekedSelEnd = True
            System.Diagnostics.Debug.WriteLine("Seek To Selection End: " & _playctrl.SelectionEnd.ToString() & " secs")
            System.Diagnostics.Debug.WriteLine("  ... playctrl.State: " & _playctrl.State.ToString())
            _playctrl.SeekSelectionEnd()
         End If
      Case "x"c
         _playctrl.Stop()

   End Select
End Sub

Private Sub ShowMediaInfo()
   Dim d As Double = 0
   Dim sa, scr, sd, sr, st As String

   sa = "Unavailable"
   scr = "Unavailable"
   sd = "Unavailable"
   sr = "Unavailable"
   st = "Unavailable"

   Try
      d = _playctrl.FrameDuration
      sa = _playctrl.Author
      scr = _playctrl.Copyright
      sd = _playctrl.Description
      sr = _playctrl.Rating
      st = _playctrl.Title
   Catch e1 As Exception
   End Try

   MessageBox.Show(_form, String.Format("Duration: {0}" _
                                        & Microsoft.VisualBasic.Constants.vbLf _
                                        & "Author: {1}" _
                                        & Microsoft.VisualBasic.Constants.vbLf _
                                        & "Copyright: {2}" _
                                        & Microsoft.VisualBasic.Constants.vbLf _
                                        & "Desc: {3}" & Microsoft.VisualBasic.Constants.vbLf _
                                        & "Rating: {4}" & Microsoft.VisualBasic.Constants.vbLf _
                                        & "Title: {5}" _
                                        & Microsoft.VisualBasic.Constants.vbLf, _
                                        d, sa, scr, sd, sr, st), "Media Info")
End Sub

Private Sub SelectedOptions()
   _playctrl.SeekStart()
   _playctrl.SeekEnd()
   Dim te As Integer = _playctrl.TrackingSelectionEnd
   Dim ts As Integer = _playctrl.TrackingSelectionStart
   Dim se As Double = _playctrl.SelectionEnd
   Dim ss As Double = _playctrl.SelectionStart
End Sub

Public NotInheritable Class LEAD_VARS
Public Const MediaDir As String = "C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 18\Media"
End Class