The Lanc Control .net Component allows rapid development of Video Control user applications. The .net Control can be added to Visual Studio's ToolBox and then dragged and dropped onto the user form just like any other control. The Component implements all functionality for the Detection, Connection and Control and Receiving of Status and Timecode.
Download:
The latest version of the control v1.0.2.0 can be downloaded by clicking here.
Properties:
| Name | Description | |
|---|---|---|
.gif)
|
DeviceID | Sets the ID of the Device to open (this is the devices serial number) |
|
|
NumOfDevices | Gets the number of Devices currently attached to the PC. |
Methods:
| Name | Description | |
|---|---|---|
.gif)
|
Close | Closes the currently open device |
|
|
EnumDeviceID | Gets the device IDs of the currently attached devices. |
|
|
SendLancCommand | Sends a LANC Command (2 or 4 bytes message, with or without repeat count) |
|
|
Open | Opens the device specified by DeviceID for communictions |
Events:
| Name | Description | |
|---|---|---|
.gif)
|
LancData | Contains the current video status and timecode, occurs on every video field. |
Example Software
Opening a Device:
The deviceID specifies the serial number of the cable to be opened for communications. The deviceID can either be "hard-cdoed" if the software will always use the same cable, or it may be got by using the EnumDeviceID method with an index of 0 - the first device).
Visual Basic
Private
Sub ButtonOpen_Click(ByVal sender As Object, ByVal e As EventArgs) Handles ButtonOpen.Click Dim myDeviceID As String = "" If LancCtrl1.EnumDeviceID(0, myDeviceID) = True ThenLancCtrl1.DeviceID = myDeviceID
LancCtrl1.Open()
ElseMsgBox(
"no device connected") End If End SubC#
private
void buttonOPEN_Click(object sender, EventArgs e){
string myDeviceID = ""; if (lancCtrl1.EnumDeviceID(0, ref myDeviceID) == true){
lancCtrl1.DeviceID = myDeviceID;
lancCtrl1.Open();
}
else{
MessageBox.Show("no device connected");}
}
Sending a Command:
The LancCommand method is used to send Lanc Commands, the method is
overloaded with 3 versions to allow 2byte, 4byte and 4byte with a repeat
count messages. The following software is used to mimic what a
'fastforward' video button may do. Whilst the button is down the video
is continuously in fastforward (cue if in play mode) and when the button is
released the ff/cue stops.
Visual Basic
Private
Sub buttonFF_MouseDown(ByVal sender As Object, ByVal e As MouseEventArgs) Handles buttonFF.MouseDownLancCtrl1.SendLancCommandVTR(LancCtrl.LancCommandVTR.FF, 0)
End Sub Private Sub buttonFF_MouseUp(ByVal sender As Object, ByVal e As MouseEventArgs) Handles buttonFF.MouseUpLancCtrl1.SendLancCommandVTR(LancCtrl.LancCommandVTR.FF)
End SubC#
private
void buttonFF_MouseUp(object sender, MouseEventArgs e){
//FF (cancel the Continuous FF by sending a single FF command)lancCtrl1.SendLancCommandVTR(
LancCommandVTR.FF);}
private void buttonREW_MouseDown(object sender, MouseEventArgs e){
//Continuous REWlancCtrl1.SendLancCommandVTR(
LancCommandVTR.REW, 0x00);}
Receiving Data:
The LancData Event is called every video field (50Hz PAL/60Hz
NTSC). The user can extract the current video data whilst processing
this event. As the Event is called from a different Thread to the GUI
(Graphical User Interface) the event should be Invoked if any GUI updates
are to be done. The following code displays the current timecode from
the video device into a text box.
Visual Basic
Private
Sub LancCtrl1_LancData(ByVal sender As Object, ByVal args As LancDataEventArgs) Handles LancCtrl1.LancData If InvokeRequired = True Then TryInvoke(
New LancDataEventHandler(AddressOf LancCtrl1_LancData), New Object() {sender, args}) Catch ex As ExceptionConsole.WriteLine(ex.ToString())
End Try ElseTextBoxTimeCodeDisplay.Text = args.framedata.Hours.ToString(
"00") & ":" & args.framedata.Minutes.ToString("00") & ":" & args.framedata.Seconds.ToString("00") & "." + args.framedata.Frames.ToString("00")TextBoxStatusDisplay.Text = args.framedata.Status.ToString()
End If End SubC#
private void lancCtrl1_LancData(object sender, LancDataEventArgs args)
{
if (InvokeRequired){
try{
Invoke(
new LancDataEventHandler(lancCtrl1_LancData), new object[] { sender, args });}
catch (Exception ex){
Console.WriteLine(ex.ToString());}
}
else{
textBoxTimeCodeDisplay.Text = args.framedata.Hours.ToString(
"00") + ":" + args.framedata.Minutes.ToString("00") + ":" + args.framedata.Seconds.ToString("00") + "." + args.framedata.Frames.ToString("00");textBoxStatusDisplay.Text = args.framedata.Status.ToString();
}
}
Example Software:
Click
here to download example software
for both a C# and Visual Basic Implementation of a very simple Video Remote
Control. The software has a drop down list of the available video devices
(which can be refreshed) which can then be opened for communication. The
display shows the Status and Time code. The control buttons allow basic
transport control but also include press and hold cue/review implementation.
