/// <summary>
/// Start the grab process in a separate thread. Once started, use the ImageGrabbed event handler and RetrieveGrayFrame/RetrieveBgrFrame to obtain the images.
/// </summary>
#if WITH_SERVICE_MODEL
/// <param name="eh">An exception handler. If provided, it will be used to handle exception in the capture thread.</param>
#endif
public void Start(
#if WITH_SERVICE_MODEL
System.ServiceModel.Dispatcher.ExceptionHandler eh = null
#endif
)
{
if (_grabState == GrabState.Pause)
{
_grabState = GrabState.Running;
_pauseEvent.Set();
}
else if (_grabState == GrabState.Stopped || _grabState == GrabState.Stopping)
{
_grabState = GrabState.Running;
#if NETSTANDARD1_4
Task t = new Task(Run);
t.Start();
#elif NETFX_CORE
ThreadPool.RunAsync(delegate { Run(); });
#elif !WITH_SERVICE_MODEL
ThreadPool.QueueUserWorkItem(delegate { Run(); });
#else
ThreadPool.QueueUserWorkItem(delegate { Run(eh); });
#endif
}
}
private void Run(
#if WITH_SERVICE_MODEL
System.ServiceModel.Dispatcher.ExceptionHandler eh = null
#endif
)
{
try
{
while (_grabState == GrabState.Running || _grabState == GrabState.Pause)
{
if (_grabState == GrabState.Pause)
{
_pauseEvent.WaitOne();
}
else if (IntPtr.Zero.Equals(_ptr) || !Grab())
{
//capture has been released, or
//no more frames to grab, this is the end of the stream.
//We should stop.
_grabState = GrabState.Stopping;
}
}
}
catch (Exception e)
{
#if WITH_SERVICE_MODEL
if (eh != null && eh.HandleException(e))
{
return;
}
#endif
throw new Exception("Capture error", e);
}
finally
{
_grabState = GrabState.Stopped;
}
}
internal static bool HandleTransportExceptionHelper(Exception exception)
{
if (exception == null)
{
throw Fx.AssertAndThrow("Null exception passed to HandleTransportExceptionHelper.");
}
System.ServiceModel.Dispatcher.ExceptionHandler transportExceptionHandler = TransportExceptionHandler;
if (transportExceptionHandler == null)
{
return(false);
}
try
{
if (!transportExceptionHandler.HandleException(exception))
{
return(false);
}
}
catch (Exception exception2)
{
if (Fx.IsFatal(exception2))
{
throw;
}
if (DiagnosticUtility.ShouldTraceError)
{
DiagnosticUtility.ExceptionUtility.TraceHandledException(exception2, TraceEventType.Error);
}
return(false);
}
if (DiagnosticUtility.ShouldTraceError)
{
DiagnosticUtility.ExceptionUtility.TraceHandledException(exception, TraceEventType.Error);
}
return(true);
}
/// <summary> /// Start the grab process in a separate thread. Once started, use the ImageGrabbed event handler and RetrieveGrayFrame/RetrieveBgrFrame to obtain the images. /// </summary> /// <param name="eh">An exception handler. If provided, it will be used to handle exception in the capture thread.</param> public void Start(System.ServiceModel.Dispatcher.ExceptionHandler eh = null)
public HandlerWrapper(System.ServiceModel.Dispatcher.ExceptionHandler handler)
{
this.handler = handler;
}
public HandlerWrapper(System.ServiceModel.Dispatcher.ExceptionHandler handler)
{
this.handler = handler;
}
