Perform the following steps to create and run a multimedia TV tuner capture application using the LEADTOOLS Multimedia CaptureCtrl control.
-
Start Visual Studio .NET 2010.
-
Choose File->New->Project... from the menu.
-
In the New Project dialog box, choose either "Visual C# Projects" or "VB Projects" in the Projects Type List, and choose "Windows Forms Application" in the Templates List.
-
Type the project name as "Multimedia TV Tuner Capture" in the Project Name field, and then click OK. If desired, type a new location for your project or select a directory using the Browse button, and then click OK.
-
In the "Solution Explorer" window, right-click the "References" folder, and select "Add Reference..." from the context menu. In the "Add Reference" dialog box, select the ".NET" tab and select Leadtools.Multimedia.dll and click OK. Also, right-click the "References" folder, and select "Add Reference..." from the context menu. In the "Add Reference" dialog box, select the "COM" tab and select:
- LEAD MPEG-2 Encoder Filter Library
Note: The above COM object must be registered. If it was not use regsvr32. For more information, refer to DirectShow Registry-free Activation.
Next click OK.
-
Make sure Form1 is in design view. Go to the toolbox (View->Toolbox) and drag a CaptureCtrl control on the form. NOTE: If you do not have CaptureCtrl in your toolbox, select Tools->Choose Toolbox Items from the menu. Click Browse and then select Leadtools.Multimedia.dll from "<LEADTOOLS_INSTALLDIR>\Bin\Dotnet\Win32" and then click Open and then click OK. After adding it to the form, set the following properties on the capture control:
| Property |
Value |
| Name |
_capturectrl |
| Anchor |
Top, Bottom, Left, Right |
-
Go to the toolbox (View->Toolbox) and drag a ProgressBar control (to be used to display capture progress) on the form (below the capture control) and set the following properties:
| Property |
Value |
| Name |
_progress |
| Anchor |
Bottom, Left, Right |
-
Go to the toolbox (View->Toolbox) and drag 4 Button controls on the bottom of the form (for Capture, TV Tuner properties, Channel Up and Channel Down) and set the following properties:
| Property |
Value |
| Name |
_buttonCapture |
| Text |
Capture |
| Anchor |
Bottom, Right |
| Name |
_buttonTuner |
| Text |
TV Tuner... |
| Anchor |
Bottom, Right |
| Name |
_buttonChannelUp |
| Text |
Up |
| Anchor |
Bottom, Right |
| Name |
_buttonChannelDown |
| Text |
Down |
| Anchor |
Bottom, Right |
-
Go to the toolbox (View->Toolbox) and drag a Label control, a Text control, another Label control and a ProgressBar control on the bottom left of the form (for a "Channel:" label, a channel text box, a "Signal:" label and a signal strength meter) and set the following properties:
| Property |
Value |
| Name |
label1 |
| Text |
Channel: |
| Anchor |
Bottom, Left |
| Name |
_textChannel |
| Anchor |
Bottom, Left |
| Locked |
True |
| ReadOnly |
True |
| TextAlign |
Center |
| Name |
label2 |
| Text |
Signal: |
| Anchor |
Bottom, Left |
| Name |
_signal |
| Anchor |
Bottom, Left |
-
Switch Form1 to code view (right-click Form1 in the Solution Explorer then choose View Code) and add the following lines to the beginning of the file:
Imports System.Runtime.InteropServices
Imports Leadtools.Multimedia
Imports LMMPEG2EncoderLib
using System.Runtime.InteropServices;
using Leadtools.Multimedia;
using LMMPEG2EncoderLib;
-
Declare the following private variables:
Private _targetFile As String
Private _captureTime As Integer
private string _targetFile;
private int _captureTime;
-
Add an event handler to the Form1 Load event and code it as follows:
Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
If _capturectrl.VideoDevices.Count = 0 Then
Throw New Exception("No capture devices available")
End If
If _capturectrl.VideoDevices("Analog") Is Nothing Then
Throw New Exception("No Analog TV capture devices available")
End If
_capturectrl.VideoDevices("Analog").Selected = True
_capturectrl.UseVideoDeviceAudio = True
_capturectrl.VideoCompressors.Mpeg2.Selected = True
_capturectrl.AudioCompressors.MpegAudio.Selected = True
_targetFile = "capture.avi"
_captureTime = 30
_capturectrl.PreviewSource = CapturePreview.VideoAndAudio
_capturectrl.Preview = True
SetCompressorProperties()
DisplayChannelAndSignal()
End Sub
private void Form1_Load(object sender, EventArgs e)
{
if (_capturectrl.VideoDevices.Count == 0)
throw new Exception("No capture devices available");
if (_capturectrl.VideoDevices["Analog"] == null)
throw new Exception("No Analog TV capture devices available");
_capturectrl.VideoDevices["Analog"].Selected = true;
_capturectrl.UseVideoDeviceAudio = true;
_capturectrl.VideoCompressors.Mpeg2.Selected = true;
_capturectrl.AudioCompressors.MpegAudio.Selected = true;
_targetFile = @"capture.avi";
_captureTime = 30;
_capturectrl.PreviewSource = CapturePreview.VideoAndAudio;
_capturectrl.Preview = true;
SetCompressorProperties();
DisplayChannelAndSignal();
}
-
Add the following helper methods as follows:
Private Sub SetCompressorProperties()
If _capturectrl.VideoCompressors.Mpeg2.Selected = True Then
Dim mpeg2Encoder As LMMPEG2Encoder = TryCast(_capturectrl.GetSubObject(CaptureObject.VideoCompressor), LMMPEG2Encoder)
If Not mpeg2Encoder Is Nothing Then
mpeg2Encoder.EncodingThreads = eMpeg2EncodingThreads.MPEG2_THREAD_AUTO
If Not _capturectrl.TVTuner Is Nothing Then
Select Case _capturectrl.TVTuner.TVFormat
Case AnalogVideoStandard.NTSC_433, AnalogVideoStandard.NTSC_M, AnalogVideoStandard.NTSC_M_J
mpeg2Encoder.VideoFormat = eMPEG2VIDEOFORMAT.MPEG2_VF_NTSC
Case AnalogVideoStandard.PAL_60, AnalogVideoStandard.PAL_B, AnalogVideoStandard.PAL_D, AnalogVideoStandard.PAL_G, AnalogVideoStandard.PAL_H, AnalogVideoStandard.PAL_I, AnalogVideoStandard.PAL_M, AnalogVideoStandard.PAL_N, AnalogVideoStandard.PAL_N_COMBO
mpeg2Encoder.VideoFormat = eMPEG2VIDEOFORMAT.MPEG2_VF_PAL
Case Else
mpeg2Encoder.VideoFormat = eMPEG2VIDEOFORMAT.MPEG2_VF_NTSC
End Select
End If
Marshal.ReleaseComObject(mpeg2Encoder)
End If
End If
End Sub
Private Sub DisplayChannelAndSignal()
If Not _capturectrl.TVTuner Is Nothing Then
Dim currChannel As Integer = _capturectrl.TVTuner.Channel
_textChannel.Text = currChannel.ToString()
Dim signal As TunerSignalStrength = _capturectrl.TVTuner.SignalPresent
Select Case signal
Case TunerSignalStrength.NoSignal
_signal.Value = 0
Case TunerSignalStrength.HasNoSignalStrength
_signal.Value = 10
Case TunerSignalStrength.SignalPresent
_signal.Value = 100
End Select
End If
End Sub
Private Sub ChangeChannel(ByVal up As Boolean)
Dim chanMin As Integer = _capturectrl.TVTuner.ChannelMin
Dim chanMax As Integer = _capturectrl.TVTuner.ChannelMax
Dim currChannel As Integer = _capturectrl.TVTuner.Channel
Dim currVideoChannel As Integer = _capturectrl.TVTuner.VideoSubChannel
If up Then
If currChannel = chanMax Then
currChannel = chanMin
Else
currChannel += 1
End If
Else
If currChannel = chanMin Then
currChannel = chanMax
Else
currChannel -= 1
End If
End If
_capturectrl.TVTuner.SetChannel(currChannel, -1, -1)
DisplayChannelAndSignal()
End Sub
private void SetCompressorProperties()
{
if (_capturectrl.VideoCompressors.Mpeg2.Selected == true)
{
LMMPEG2Encoder mpeg2Encoder = _capturectrl.GetSubObject(CaptureObject.VideoCompressor) as LMMPEG2Encoder;
if (mpeg2Encoder != null)
{
mpeg2Encoder.EncodingThreads = eMpeg2EncodingThreads.MPEG2_THREAD_AUTO;
if (_capturectrl.TVTuner != null)
{
switch (_capturectrl.TVTuner.TVFormat)
{
default:
case AnalogVideoStandard.NTSC_433:
case AnalogVideoStandard.NTSC_M:
case AnalogVideoStandard.NTSC_M_J:
mpeg2Encoder.VideoFormat = eMPEG2VIDEOFORMAT.MPEG2_VF_NTSC;
break;
case AnalogVideoStandard.PAL_60:
case AnalogVideoStandard.PAL_B:
case AnalogVideoStandard.PAL_D:
case AnalogVideoStandard.PAL_G:
case AnalogVideoStandard.PAL_H:
case AnalogVideoStandard.PAL_I:
case AnalogVideoStandard.PAL_M:
case AnalogVideoStandard.PAL_N:
case AnalogVideoStandard.PAL_N_COMBO:
mpeg2Encoder.VideoFormat = eMPEG2VIDEOFORMAT.MPEG2_VF_PAL;
break;
}
}
Marshal.ReleaseComObject(mpeg2Encoder);
}
}
}
private void DisplayChannelAndSignal()
{
if (_capturectrl.TVTuner != null)
{
int currChannel = _capturectrl.TVTuner.Channel;
_textChannel.Text = currChannel.ToString();
TunerSignalStrength signal = _capturectrl.TVTuner.SignalPresent;
switch (signal)
{
case TunerSignalStrength.NoSignal:
_signal.Value = 0;
break;
case TunerSignalStrength.HasNoSignalStrength:
_signal.Value = 10;
break;
case TunerSignalStrength.SignalPresent:
_signal.Value = 100;
break;
}
}
}
private void ChangeChannel(bool up)
{
int chanMin = _capturectrl.TVTuner.ChannelMin;
int chanMax = _capturectrl.TVTuner.ChannelMax;
int currChannel = _capturectrl.TVTuner.Channel;
int currVideoChannel = _capturectrl.TVTuner.VideoSubChannel;
if (up)
{
if (currChannel == chanMax)
currChannel = chanMin;
else
currChannel++;
}
else
{
if (currChannel == chanMin)
currChannel = chanMax;
else
currChannel--;
}
_capturectrl.TVTuner.SetChannel(currChannel, -1, -1);
DisplayChannelAndSignal();
}
-
Add an event handler to the _capturectrl Progress event and code it as follows:
Private Sub _capturectrl_Progress(ByVal sender As System.Object, ByVal e As ProgressEventArgs) Handles _capturectrl.Progress
_progress.Value = CInt((_progress.Maximum * e.time) / (_captureTime * 1000))
End Sub
private void _capturectrl_Progress(object sender, ProgressEventArgs e)
{
_progress.Value = (int)((_progress.Maximum * e.time) / (_captureTime * 1000));
}
-
Add an event handler to the _capturectrl Complete event and code it as follows:
Private Sub _capturectrl_Complete(ByVal sender As System.Object, ByVal e As EventArgs) Handles _capturectrl.Complete
MessageBox.Show("Capture Complete")
_buttonCapture.Enabled = True
End Sub
private void _capturectrl_Complete(object sender, EventArgs e)
{
MessageBox.Show("Capture Complete");
_buttonCapture.Enabled = true;
}
-
Add an event handler to the _buttonTuner Click event and code it as follows:
Private Sub _buttonTuner_Click(ByVal sender As Object, ByVal e As EventArgs) Handles _buttonTuner.Click
If Not _capturectrl.TVTuner Is Nothing Then
If _capturectrl.HasDialog(CaptureDlg.TVTuner) Then
_capturectrl.ShowDialog(CaptureDlg.TVTuner, Me)
End If
DisplayChannelAndSignal()
End If
End Sub
private void _buttonTuner_Click(object sender, EventArgs e)
{
if (_capturectrl.TVTuner != null)
{
if (_capturectrl.HasDialog(CaptureDlg.TVTuner))
_capturectrl.ShowDialog(CaptureDlg.TVTuner, this);
DisplayChannelAndSignal();
}
}
-
Add an event handler to the _buttonChannelUp Click event and code it as follows:
Private Sub _buttonChannelUp_Click(ByVal sender As Object, ByVal e As EventArgs) Handles _buttonChannelUp.Click
If Not _capturectrl.TVTuner Is Nothing Then
ChangeChannel(True)
End If
End Sub
private void _buttonChannelUp_Click(object sender, EventArgs e)
{
if (_capturectrl.TVTuner != null)
{
ChangeChannel(true);
}
}
-
Add an event handler to the _buttonChannelDown Click event and code it as follows:
Private Sub _buttonChannelDown_Click(ByVal sender As Object, ByVal e As EventArgs) Handles _buttonChannelDown.Click
If Not _capturectrl.TVTuner Is Nothing Then
ChangeChannel(False)
End If
End Sub
private void _buttonChannelDown_Click(object sender, EventArgs e)
{
if (_capturectrl.TVTuner != null)
{
ChangeChannel(false);
}
}
-
Add an event handler to the _buttonCapture Click event and code it as follows:
Private Sub _buttonCapture_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles _buttonCapture.Click
Try
_capturectrl.Preview = True
_capturectrl.TargetFile = _targetFile
_capturectrl.UseTimeLimit = True
_capturectrl.TimeLimit = _captureTime
_capturectrl.StartCapture(CaptureMode.VideoAndAudio)
_buttonCapture.Enabled = False
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End Sub
private void _buttonCapture_Click(object sender, System.EventArgs e)
{
try
{
_capturectrl.Preview = true;
_capturectrl.TargetFile = _targetFile;
_capturectrl.UseTimeLimit = true;
_capturectrl.TimeLimit = _captureTime;
_capturectrl.StartCapture(CaptureMode.VideoAndAudio);
_buttonCapture.Enabled = false;
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
-
Build, and Run the program to test it.
