UseFilterCache Property

Summary

Gets or sets a value that determines whether the toolkit is currently caching filters.

Syntax
C#
VB
C++
public bool UseFilterCache { get; set; } 
Public Property UseFilterCache As Boolean 
public: 
property bool UseFilterCache { 
   bool get(); 
   void set (    bool ); 
} 

Property Value

true to enable caching filters; otherwise, it is false to disable caching filters. The default value is false.

Remarks

Setting this property to true will enable caching for the current target format object. The target format object is the format that will be used for the converted file. This includes the file format, any special settings used by the format, which audio/video codec is used for the conversion and any special settings used by the codec. Additionally, setting this property to true will force the toolkit to preload and reuse the filters specified for the particular format. If an object isn't currently created, one will be created. Setting the value of this property to false will disable the caching for the current target format object. If an object currently exists, it will destroy it.

Use the TargetFormat.GetCacheObject method to retrieve the caching filter object. Use the TargetFormat.ShowCacheDialog method to display a specific property dialog for the caching filter.

Use the TargetFormat.HasCacheDialog method to query whether the specified property dialog for the caching filter is available.

Example
C#
VB
using Leadtools; 
using Leadtools.Multimedia; 
using LeadtoolsMultimediaExamples.Fixtures; 
 
public bool _result = false; 
public CaptureCtrlForm _form = new CaptureCtrlForm(); 
public LMMpg2MxTLib.LMMpg2MxT _pMpgMux; 
 
// This example will show you the correct way to set up a muxer's properties during capture 
// Normally, the muxer is added only after the capture graph has been build with ReadyCapture or StartCapture 
// But at this point, the graph is in running mode, so some muxer operations might fail 
// If you need to make changes to the muxer in stopped state (like adding KLV data stream, for example), 
// then you need to change the muxer before the graph is fully built. You can do so by instructing the toolkit 
// to cache the target filters by setting the TargetFormat.UseFilterCache property to true 
// In this situation, the filters used to implement a certain target format are created and used whenever  
// you set that target format. 
// 
// This example will show you how to add KLV data to a MPEG-2 Transport Stream in a capture situation. 
public void UseFilterCacheExample() 
{ 
   // reference the capture control 
   CaptureCtrl capturectrl = _form.CaptureCtrl; 
   string outFile = Path.Combine(LEAD_VARS.MediaDir, "CaptureKLV.mpg"); 
 
   try 
   { 
      // select the capture device 
      capturectrl.VideoDevices.Selection = 0; /* Use a different video device if you want */ 
 
      /* capturectrl.Preview = true; -- enable this if you want */ 
 
      /* set the video compressor (only if the capture device is not already capturing compressed video) */ 
      capturectrl.VideoCompressors.Mpeg2.Selected = true; 
 
      // set the target output file 
      capturectrl.TargetFile = outFile; 
 
      // subscribe to the started event 
      capturectrl.Started += new System.EventHandler(this.CaptureCtrl_Started); 
 
      // just 10 seconds of capture time 
      capturectrl.TimeLimit = 10; 
      capturectrl.UseTimeLimit = true; 
 
      // subscribe to the complete event 
      capturectrl.Complete += new EventHandler(CaptureCtrl_Complete); 
 
      // IN a capture situation  
      //in order to get the mux in a capture situation, set the UseFilterCache property for the target format to TRUE 
      //      This tells the toolkit to create a Mux object and keep it around when building or rebuilding graphs 
      capturectrl.TargetFormats[Leadtools.Multimedia.TargetFormatType.MPEG2Transport].UseFilterCache = true; 
      capturectrl.TargetFormat = Leadtools.Multimedia.TargetFormatType.MPEG2Transport; 
 
      _pMpgMux = (LMMpg2MxTLib.LMMpg2MxT)capturectrl.TargetFormats[Leadtools.Multimedia.TargetFormatType.MPEG2Transport].GetCacheObject(TargetFormatObject.Mux); 
      if (_pMpgMux != null) 
      { 
         _pMpgMux.PrivateDataPID = 0x70; 
         _pMpgMux.PrivateDataFormatID = 0x41564c4b; 
         _pMpgMux.EnablePrivateData = true; 
      } 
 
      // start capture 
      capturectrl.StartCapture(Leadtools.Multimedia.CaptureMode.Video); 
      _result = true; 
   } 
   catch (Exception) 
   { 
      _result = false; 
   } 
} 
 
private void WriteKLVData(LMMpg2MxTLib.LMMpg2MxT pMpgMux) 
{ 
   // get the current time since Jan 1, 1970 
   TimeSpan basetime = DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0); 
   // get the number of microseconds since Jan 1, 1970 
   Int64 timestamp = (Int64)basetime.TotalSeconds * 1000000; 
   // do not really need to do this, since I am writing only one item 
   pMpgMux.KlvBuilder.Clear(); 
   // write the UDS timestamp (number of microseconds since Jan 1, 1970) 
   pMpgMux.KlvBuilder.InsertUInt64(-1, "06 0E 2B 34 01 01 01 03 07 02 01 01 01 05 00 00", (ulong)timestamp); 
   // write one KLV data at the beginning 
   pMpgMux.WritePrivateData((int)LMMpg2MxTLib.Mpg2MxT_WriteFlags.Mpg2MxT_WriteFlag_PTSValid | 
                            (int)LMMpg2MxTLib.Mpg2MxT_WriteFlags.Mpg2MxT_WriteFlag_PTSInSeconds, 
                            0.0, pMpgMux.KlvBuilder.GetData(), 
                            -1); 
   // close the stream 
   pMpgMux.ClosePrivateData(); 
} 
 
private void CaptureCtrl_Started(object sender, EventArgs e) 
{ 
   WriteKLVData(_pMpgMux); 
} 
 
private void CaptureCtrl_Complete(object sender, EventArgs e) 
{ 
   // set result 
   _result = true; 
} 
 
static class LEAD_VARS 
{ 
   public const string MediaDir = @"C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 20\Media"; 
} 
Imports Leadtools 
Imports Leadtools.Multimedia 
Imports LeadtoolsMultimediaExamples.Fixtures 
 
Public _result As Boolean = False 
Public _form As CaptureCtrlForm = New CaptureCtrlForm() 
Public _pMpgMux As LMMpg2MxTLib.LMMpg2MxT 
 
' This example will show you the correct way to set up a muxer's properties during capture 
' Normally, the muxer is added only after the capture graph has been build with ReadyCapture or StartCapture 
' But at this point, the graph is in running mode, so some muxer operations might fail 
' If you need to make changes to the muxer in stopped state (like adding KLV data stream, for example), 
' then you need to change the muxer before the graph is fully built. You can do so by instructing the toolkit 
' to cache the target filters by setting the TargetFormat.UseFilterCache property to true 
' In this situation, the filters used to implement a certain target format are created and used whenever  
' you set that target format. 
 
' This example will show you how to add KLV data to a MPEG-2 Transport Stream in a capture situation. 
 
Public Sub UseFilterCacheExample() 
   ' reference the capture control 
   Dim capturectrl As CaptureCtrl = _form.CaptureCtrl 
   Dim outFile As String = Path.Combine(LEAD_VARS.MediaDir, "CaptureKLV.mpg") 
 
   Try 
      ' select the capture device 
      capturectrl.VideoDevices.Selection = 0 ' Use a different video device if you want  
 
      ' capturectrl.Preview = true; -- enable this if you want  
 
 
      ' set the video compressor (only if the capture device is not already capturing compressed video) 
 
      capturectrl.VideoCompressors.Mpeg2.Selected = True 
 
      ' set the target output file 
      capturectrl.TargetFile = outFile 
 
      ' subscribe to the compete event 
      AddHandler capturectrl.Started, AddressOf CaptureCtrl_Started 
 
      ' just 10 seconds of capture time 
      capturectrl.TimeLimit = 10 
      capturectrl.UseTimeLimit = True 
 
      ' subscribe to the compete event 
      AddHandler capturectrl.Complete, AddressOf CaptureCtrl_Complete 
 
      ' IN a capture situation  
      'in order to get the mux in a capture situation, set the UseFilterCache property for the target format to TRUE 
      '      This tells the toolkit to create a Mux object and keep it around when building or rebuilding graphs 
      capturectrl.TargetFormats(Leadtools.Multimedia.TargetFormatType.MPEG2Transport).UseFilterCache = True 
      capturectrl.TargetFormat = Leadtools.Multimedia.TargetFormatType.MPEG2Transport 
 
      _pMpgMux = DirectCast(capturectrl.TargetFormats(Leadtools.Multimedia.TargetFormatType.MPEG2Transport).GetCacheObject(TargetFormatObject.Mux), LMMpg2MxTLib.LMMpg2MxT) 
      If _pMpgMux IsNot Nothing Then 
         _pMpgMux.PrivateDataPID = &H70 
         _pMpgMux.PrivateDataFormatID = &H41564C4B 
         _pMpgMux.EnablePrivateData = True 
      End If 
 
      ' start capture 
      capturectrl.StartCapture(Leadtools.Multimedia.CaptureMode.Video) 
      _result = True 
   Catch generatedExceptionName As Exception 
      _result = False 
   End Try 
End Sub 
 
Private Sub WriteKLVData(ByVal pMpgMux As LMMpg2MxTLib.LMMpg2MxT) 
   ' get the current time since Jan 1, 1970 
   Dim basetime As TimeSpan = DateTime.UtcNow - New DateTime(1970, 1, 1, 0, 0, 0) 
   ' get the number of microseconds since Jan 1, 1970 
   Dim timestamp As Int64 = CLng(basetime.TotalSeconds) * 1000000 
   ' don't really need to do this, since I am writing only one item 
   pMpgMux.KlvBuilder.Clear() 
   ' write the UDS timestamp (number of microseconds since Jan 1, 1970) 
   pMpgMux.KlvBuilder.InsertUInt64(-1, "06 0E 2B 34 01 01 01 03 07 02 01 01 01 05 00 00", CULng(timestamp)) 
   ' write one KLV data at the beginning 
   pMpgMux.WritePrivateData(CInt(LMMpg2MxTLib.Mpg2MxT_WriteFlags.Mpg2MxT_WriteFlag_PTSValid) _ 
                            Or CInt(LMMpg2MxTLib.Mpg2MxT_WriteFlags.Mpg2MxT_WriteFlag_PTSInSeconds), 
                            0.0, pMpgMux.KlvBuilder.GetData(), -1) 
   ' close the stream 
   pMpgMux.ClosePrivateData() 
End Sub 
 
Public Sub CaptureCtrl_Started(ByVal sender As Object, ByVal e As EventArgs) 
   WriteKLVData(_pMpgMux) 
End Sub 
 
Public Sub CaptureCtrl_Complete(ByVal sender As Object, ByVal e As EventArgs) 
   ' set result 
   _result = True 
End Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const MediaDir As String = "C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 20\Media" 
End Class 
Requirements

Target Platforms

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Leadtools.Multimedia Assembly