Laser Gesture Recognition

namespace dshow.Core
{
	using System;
	using System.Runtime.InteropServices;

	// IMediaEvent interface
	//
	// The IMediaEvent interface contains methods for retrieving event
	// notifications and for overriding the filter graph's default
	// handling of events.
	//
	[ComImport,
	Guid("56A868B6-0AD4-11CE-B03A-0020AF0BA770"),
	InterfaceType(ComInterfaceType.InterfaceIsDual)]
	public interface IMediaEvent
	{
		// Retrieves a handle to a manual-reset event that remains
		// signaled while the queue contains event notifications
		[PreserveSig]
		int GetEventHandle(
			out IntPtr hEvent);

		// Retrieves the next event notification from the event queue
		[PreserveSig]
		int GetEvent(
			out int lEventCode,
			out int lParam1,
			out int lParam2,
			int msTimeout);

		// Waits for the filter graph to render all available data
		[PreserveSig]
		int GetEvent(
			int msTimeout,
			out int pEvCode);

		// Cancels the filter graph manager's default handling of
		// a specified event
		[PreserveSig]
		int CancelDefaultHandling(
			int lEvCode);

		// Restores the filter graph manager's default handling of
		// a specified event
		[PreserveSig]
		int RestoreDefaultHandling(
			int lEvCode);

		// Frees resources associated with the parameters of an event
		[PreserveSig]
		int FreeEventParams(
			int lEventCode,
			int lParam1,
			int lParam2);
	}


	// IMediaEventEx interface
	//
	// IMediaEventEx adds methods that enable an application window
	// to receive messages when events occur
	//
	[ComImport,
	Guid("56A868C0-0AD4-11CE-B03A-0020AF0BA770"),
	InterfaceType(ComInterfaceType.InterfaceIsDual)]
	public interface IMediaEventEx
	{
		// Retrieves a handle to a manual-reset event that remains
		// signaled while the queue contains event notifications
		[PreserveSig]
		int GetEventHandle(
			out IntPtr hEvent);

		// Retrieves the next event notification from the event queue
		[PreserveSig]
		int GetEvent(
			out int lEventCode,
			out int lParam1,
			out int lParam2,
			int msTimeout);

		// Waits for the filter graph to render all available data
		[PreserveSig]
		int WaitForCompletion(
			int msTimeout,
			out int pEvCode);

		// Cancels the filter graph manager's default handling of
		// a specified event
		[PreserveSig]
		int CancelDefaultHandling(
			int lEvCode);

		// Restores the filter graph manager's default handling of
		// a specified event
		[PreserveSig]
		int RestoreDefaultHandling(
			int lEvCode);

		// Frees resources associated with the parameters of an event
		[PreserveSig]
		int FreeEventParams(
			int lEventCode,
			int lParam1,
			int lParam2);

		// Registers a window to process event notifications
		[PreserveSig]
		int SetNotifyWindow(
			IntPtr hwnd,
			int lMsg,
			IntPtr lInstanceData);

		// Enables or disables event notifications
		// 0 - ON, 1 - OFF
		[PreserveSig]
		int SetNotifyWindow(
			int lNoNotifyFlags);

		// Determines whether event notifications are enabled
		[PreserveSig]
		int GetNotifyFlags(
			out int lNoNotifyFlags);
	}
}