WriteScriptStream Method

Adds a stream-based script to be executed at a particular time during playback.

Syntax

Visual Basic
C#
WinRT C#
WinRT JavaScript
C++

public void WriteScriptStream( 
   string ScriptType,
   string ScriptCommand,
   double ScriptTime
)

'Declaration
 
Public Sub WriteScriptStream( _
   ByVal ScriptType As String, _
   ByVal ScriptCommand As String, _
   ByVal ScriptTime As Double _
)

'Usage
 
Dim instance As WMScript
Dim ScriptType As String
Dim ScriptCommand As String
Dim ScriptTime As Double
 
instance.WriteScriptStream(ScriptType, ScriptCommand, ScriptTime)

public void WriteScriptStream( 
   string ScriptType,
   string ScriptCommand,
   double ScriptTime
)

 function Leadtools.Multimedia.WMScript.WriteScriptStream( 
   ScriptType ,
   ScriptCommand ,
   ScriptTime 
)

public:
void WriteScriptStream( 
   String^ ScriptType,
   String^ ScriptCommand,
   double ScriptTime
)

Parameters

ScriptType: The name of the script command.
ScriptCommand: The script command.
ScriptTime: Time (in seconds) when the script command should execute.

Remarks

Header scripts are added when you know how many scripts you have and their location beforehand. Also, since they are stored in the header, they will need to be all downloaded before playback begins.

Stream scripts are added when you don't know how many you will have or when there are too many and you don't want to slow down the start of the playback. For example, if you have a live capture and there are certain notifications that you will receive during the capture, you would use stream scripts.

Stream scripts can be processed using the MediaEventHandler event handler for PlayCtrl. Stream script commands generate EC_OLE_EVENT event codes. See Processing Windows Media Script Commands for an example of how Stream Scripts are processed.

See the Microsoft documentation, Using Script Commands Supported by Windows Media Player, for a complete list of script commands supported by Windows Media Player.

Example

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Public _result As Boolean = False
      Public _form As New CaptureCtrlForm()
      Public _startTime As DateTime
      Private _capturectrl As CaptureCtrl
      Private _mux As WMScript
      Public Sub WriteScriptStreamExample()
         _capturectrl = _form.CaptureCtrl

         ' reference the capture control
         Dim outFile As String = Path.Combine(LEAD_VARS.MediaDir, "WriteScriptStream_Dest.wmv")

         Try
            _capturectrl.TargetFormat = TargetFormatType.WMVMux
            _capturectrl.TargetFile = outFile

            ' set an audio device, use the name of your device here
            If _capturectrl.VideoDevices("Logitech") Is Nothing Then
               Throw New Exception("No USB audio device available")
            End If

            _capturectrl.VideoDevices("Logitech").Selected = True

            If _capturectrl.IsModeAvailable(CaptureMode.Video) Then

               _capturectrl.FrameDelay = 0.033 ' 30 frames per second

               _capturectrl.TimeLimit = 10 ' just 10 seconds of capture time
               _capturectrl.UseTimeLimit = True

               ' call ReadyCapture, so the target object is added
               _capturectrl.ReadyCapture(CaptureMode.Video Or CaptureMode.InhibitRun)

               ' get the scripter object
               _mux = _capturectrl.WMScripter
               If _mux Is Nothing Then
                  Return
               End If

               ' enable the script stream
               _mux.EnableScriptStream = True

               ' subscribe to the complete event
               AddHandler _capturectrl.Complete, AddressOf CaptureCtrl_Complete

               ' subscribe to the error abort event
               AddHandler _capturectrl.ErrorAbort, AddressOf CaptureCtrl_ErrorAbort

               ' set the start time
               _startTime = DateTime.Now

               ' set a timer so we can write the Script commands every second
               _form.TestTimer.Interval = 1000
               AddHandler _form.TestTimer.Tick, AddressOf TestTimer_Tick
               _form.TestTimer.Start()

               ' start the capture process
               _capturectrl.StartCapture(CaptureMode.Video)

               ' 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
         Catch generatedExceptionName As Exception
            Return
         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.
         While _capturectrl.State = CaptureState.Running
            Application.DoEvents()
         End While

         _result = True
      End Sub

      Public Sub TestTimer_Tick(ByVal sender As Object, ByVal e As EventArgs)
         ' stop the capture
         Try
            Dim elapsedTime As Double = (DateTime.Now - _startTime).TotalMilliseconds / 1000
            Dim sz As [String] = [String].Format("Sample caption script at {0} seconds", elapsedTime)
            _mux.WriteScriptStream("caption", sz, elapsedTime)
         Catch generatedExceptionName As Exception
            _result = False
            _capturectrl.StopCapture()
         End Try
      End Sub

      Public Sub CaptureCtrl_Complete(ByVal sender As Object, ByVal e As EventArgs)
         ' set result
         _result = True
         ' the capture has finished, don't write scripts anymore
         ' Note that since the capture has finished automatically, I don't need to call _mux.CloseScriptStream()
         _form.TestTimer.[Stop]()
      End Sub

      Public Sub CaptureCtrl_ErrorAbort(ByVal sender As Object, ByVal e As ErrorAbortEventArgs)
         ' set result
         _result = False
         ' the capture has finished, don't write scripts anymore
         ' Note that since the capture has finished automatically, I don't need to call _mux.CloseScriptStream()
         _form.TestTimer.[Stop]()
      End Sub

Public NotInheritable Class LEAD_VARS
   Public Const MediaDir As String = "C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 175\Media";
End Class

public bool _result = false;
      public CaptureCtrlForm _form = new CaptureCtrlForm();
      public DateTime _startTime;
      CaptureCtrl _capturectrl;
      WMScript _mux;
      public void WriteScriptStreamExample()
      {
         _capturectrl = _form.CaptureCtrl;

         // reference the capture control
         string outFile = Path.Combine(LEAD_VARS.MediaDir,"WriteScriptStream_Dest.wmv");

         try
         {
            _capturectrl.TargetFormat = TargetFormatType.WMVMux;
            _capturectrl.TargetFile = outFile;

            // set an audio device, use the name of your device here
            if(_capturectrl.VideoDevices["Logitech"] == null)
               throw new Exception("No USB audio device available");

            _capturectrl.VideoDevices["Logitech"].Selected = true;

            if (_capturectrl.IsModeAvailable(CaptureMode.Video))
            {
               _capturectrl.FrameDelay = .033;  // 30 frames per second
               _capturectrl.TimeLimit = 10;     // just 10 seconds of capture time
               _capturectrl.UseTimeLimit = true;

               // call ReadyCapture, so the target object is added
               _capturectrl.ReadyCapture(CaptureMode.Video | CaptureMode.InhibitRun);

               // get the scripter object
               _mux = _capturectrl.WMScripter;
               if(_mux == null)
                  return;

               // enable the script stream
               _mux.EnableScriptStream = true;

               // subscribe to the complete event
               _capturectrl.Complete += new EventHandler(CaptureCtrl_Complete);

               // subscribe to the error abort event
               _capturectrl.ErrorAbort += new ErrorAbortEventHandler(CaptureCtrl_ErrorAbort);

               // set the start time
               _startTime = DateTime.Now;

               // set a timer so we can write the Script commands every second
               _form.TestTimer.Interval = 1000;
               _form.TestTimer.Tick += new EventHandler(TestTimer_Tick);
               _form.TestTimer.Start();

               // start the capture process
               _capturectrl.StartCapture(CaptureMode.Video);

               // 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();
            }
         }
         catch (Exception)
         {
            return;
         }

         // 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();

         _result = true;
      }

      public void TestTimer_Tick(object sender, EventArgs e)
      {
         // stop the capture
         try
         {
            double elapsedTime = (DateTime.Now - _startTime).TotalMilliseconds / 1000;
            String sz = String.Format("Sample caption script at {0} seconds", elapsedTime);
            _mux.WriteScriptStream("caption", sz, elapsedTime);
         }
         catch(Exception)
         {
            _result = false;
            _capturectrl.StopCapture();
         }
      }

      public void CaptureCtrl_Complete(object sender, EventArgs e)
      {
         // set result
         _result = true;
         // the capture has finished, do not write scripts anymore
         // Note that since the capture has finished automatically, I do not need to call _mux.CloseScriptStream()
         _form.TestTimer.Stop();
      }

      public void CaptureCtrl_ErrorAbort(object sender, ErrorAbortEventArgs e)
      {
         // set result
         _result = false;
         // the capture has finished, do not write scripts anymore
         // Note that since the capture has finished automatically, I do not need to call _mux.CloseScriptStream()
         _form.TestTimer.Stop();
      }

static class LEAD_VARS
{
   public const string MediaDir = @"C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 175\Media";
}

Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

WMScript Class
WMScript Members