DirectShow Webcam Memory Leak Problem

[Sven Bauermann]

Hallo,

ich hänge nun schon ein längeres Weilchen an einem Memory Leak.

Dieser Code stammt aus einem alten Code Projekt
Example: http://www.codeproject.com/KB/directx/directshownet.aspx?msg=
1011979#xx1011979xx

Hier geht direkt beim Aufruf des mediaCtrl.Run() der Speicher massvie
hoch ca. 11MB und wird auch nach Aufruf der CloseInterfaces() Funktion
nicht wieder abgebaut. Ein Blick mit Memory Profiler 4.0 zeigt genaue
diesen Speicherwert in der ntdll.dll im virtuellen Speicher.

Ich habe alles gelöscht was man nur löschen, disposen,
Marshal.ReleaseComObject releasen kann aber mit jeden neuen Start des
WebCam Stream erhöht sich der Speicher um ca. 11MB?

Ausnahmsweise die komplette Klasse, da ich nicht genau sagen kann, wo
man noch suchen müßte.

LG
Sven






[STAThread]
static void Main()
{
Application.Run(new MainForm());
GC.Collect();
GC.WaitForPendingFinalizers();
}

private void MainForm_Closing(object sender,
System.ComponentModel.CancelEventArgs e)
{
this.Hide();
CloseInterfaces();
}

/// <summary> detect first form appearance, start grabber.
</summary>
private void MainForm_Activated(object sender, System.EventArgs
e)
{
if( firstActive )
return;
firstActive = true;

if( ! DsUtils.IsCorrectDirectXVersion() )
{
MessageBox.Show( this, "DirectX 8.1 NOT installed!",
"DirectShow.NET", MessageBoxButtons.OK, MessageBoxIcon.Stop );
this.Close(); return;
}

if( ! DsDev.GetDevicesOfCat(
FilterCategory.VideoInputDevice, out capDevices ) )
{
MessageBox.Show( this, "No video capture devices
found!", "DirectShow.NET", MessageBoxButtons.OK, MessageBoxIcon.Stop );
this.Close(); return;
}

DsDevice dev = null;
if( capDevices.Count == 1 )
dev = capDevices[0] as DsDevice;
else
{
DeviceSelector selector = new DeviceSelector(
capDevices );
selector.ShowDialog( this );
dev = selector.SelectedDevice;
}

if( dev == null )
{
this.Close(); return;
}

if( ! StartupVideo( dev.Mon ) )
this.Close();
}

private void videoPanel_Resize(object sender, System.EventArgs e)
{
ResizeVideoWindow();
}


/// <summary> handler for toolbar button clicks. </summary>
private void toolBar_ButtonClick(object sender,
System.Windows.Forms.ToolBarButtonClickEventArgs e)
{
Trace.WriteLine( "!!BTN: toolBar_ButtonClick" );

int hr;
if( sampGrabber == null )
return;

if( e.Button == toolBarBtnGrab )
{
Trace.WriteLine( "!!BTN: toolBarBtnGrab" );

if( savedArray == null )
{
int size =
videoInfoHeader.BmiHeader.ImageSize;
if( (size < 1000) || (size > 16000000) )
return;
savedArray = new byte[ size + 64000 ];
}

toolBarBtnSave.Enabled = false;
Image old = pictureBox.Image;
pictureBox.Image = null;
if( old != null )
old.Dispose();

toolBarBtnGrab.Enabled = false;
captured = false;
hr = sampGrabber.SetCallback( this, 1 );
}
else if( e.Button == toolBarBtnSave )
{
Trace.WriteLine( "!!BTN: toolBarBtnSave" );

SaveFileDialog sd = new SaveFileDialog();
sd.FileName = @"DsNET.bmp";
sd.Title = "Save Image as...";
sd.Filter = "Bitmap file (*.bmp)|*.bmp";
sd.FilterIndex = 1;
if( sd.ShowDialog() != DialogResult.OK )
return;

pictureBox.Image.Save( sd.FileName, ImageFormat.Bmp
); // save to new bmp file
}
else if( e.Button == toolBarBtnTune )
{
if( capGraph != null )
DsUtils.ShowTunerPinDialog( capGraph,
capFilter, this.Handle );
}

}

/// <summary> capture event, triggered by buffer callback.
</summary>
void OnCaptureDone()
{
Trace.WriteLine( "!!DLG: OnCaptureDone" );
try {
toolBarBtnGrab.Enabled = true;
int hr;
if( sampGrabber == null )
return;
hr = sampGrabber.SetCallback( null, 0 );

int w = videoInfoHeader.BmiHeader.Width;
int h = videoInfoHeader.BmiHeader.Height;
if( ((w & 0x03) != 0) || (w < 32) || (w > 4096) ||
(h < 32) || (h > 4096) )
return;
int stride = w * 3;

GCHandle handle = GCHandle.Alloc( savedArray,
GCHandleType.Pinned );
int scan0 = (int) handle.AddrOfPinnedObject();
scan0 += (h - 1) * stride;
Bitmap b = new Bitmap( w, h, -stride,
PixelFormat.Format24bppRgb, (IntPtr) scan0 );
handle.Free();
savedArray = null;
Image old = pictureBox.Image;
pictureBox.Image = b;
if( old != null )
old.Dispose();
toolBarBtnSave.Enabled = true;
}
catch( Exception ee )
{
MessageBox.Show( this, "Could not grab picture\r\n"
+ ee.Message, "DirectShow.NET", MessageBoxButtons.OK,
MessageBoxIcon.Stop );
}
}



/// <summary> start all the interfaces, graphs and preview
window. </summary>
bool StartupVideo( UCOMIMoniker mon )
{
int hr;
try {
if( ! CreateCaptureDevice( mon ) )
return false;

if( ! GetInterfaces() )
return false;

if( ! SetupGraph() )
return false;

if( ! SetupVideoWindow() )
return false;

#if DEBUG
DsROT.AddGraphToRot( graphBuilder, out
rotCookie ); // graphBuilder capGraph
#endif

hr = mediaCtrl.Run();
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

bool hasTuner = DsUtils.ShowTunerPinDialog(
capGraph, capFilter, this.Handle );
toolBarBtnTune.Enabled = hasTuner;

return true;
}
catch( Exception ee )
{
MessageBox.Show( this, "Could not start video stream
\r\n" + ee.Message, "DirectShow.NET", MessageBoxButtons.OK,
MessageBoxIcon.Stop );
return false;
}
}

/// <summary> make the video preview window to show in
videoPanel. </summary>
bool SetupVideoWindow()
{
int hr;
try {
// Set the video window to be a child of the main
window
hr = videoWin.put_Owner( videoPanel.Handle );
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

// Set video window style
hr = videoWin.put_WindowStyle( WS_CHILD |
WS_CLIPCHILDREN );
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

// Use helper function to position video window in
client rect of owner window
ResizeVideoWindow();

// Make the video window visible, now that it is
properly positioned
hr = videoWin.put_Visible( DsHlp.OATRUE );
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

hr = mediaEvt.SetNotifyWindow( this.Handle,
WM_GRAPHNOTIFY, IntPtr.Zero );
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );
return true;
}
catch( Exception ee )
{
MessageBox.Show( this, "Could not setup video window
\r\n" + ee.Message, "DirectShow.NET", MessageBoxButtons.OK,
MessageBoxIcon.Stop );
return false;
}
}


/// <summary> build the capture graph for grabber.
</summary>
bool SetupGraph()
{
int hr;
try {
hr = capGraph.SetFiltergraph( graphBuilder );
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

hr = graphBuilder.AddFilter( capFilter, "Ds.NET
Video Capture Device" );
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

DsUtils.ShowCapPinDialog( capGraph, capFilter,
this.Handle );

AMMediaType media = new AMMediaType();
media.majorType = MediaType.Video;
media.subType = MediaSubType.RGB24;
media.formatType = FormatType.VideoInfo; //
???
hr = sampGrabber.SetMediaType( media );
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

hr = graphBuilder.AddFilter( baseGrabFlt, "Ds.NET
Grabber" );
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

Guid cat = PinCategory.Preview;
Guid med = MediaType.Video;
hr = capGraph.RenderStream( ref cat, ref med,
capFilter, null, null ); // baseGrabFlt
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

cat = PinCategory.Capture;
med = MediaType.Video;
hr = capGraph.RenderStream( ref cat, ref med,
capFilter, null, baseGrabFlt ); // baseGrabFlt
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

media = new AMMediaType();
hr = sampGrabber.GetConnectedMediaType( media );
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );
if( (media.formatType != FormatType.VideoInfo) ||
(media.formatPtr == IntPtr.Zero) )
throw new NotSupportedException( "Unknown
Grabber Media Format" );

videoInfoHeader = (VideoInfoHeader)
Marshal.PtrToStructure( media.formatPtr, typeof(VideoInfoHeader) );
Marshal.FreeCoTaskMem( media.formatPtr );
media.formatPtr = IntPtr.Zero;

hr = sampGrabber.SetBufferSamples( false );
if( hr == 0 )
hr = sampGrabber.SetOneShot( false );
if( hr == 0 )
hr = sampGrabber.SetCallback( null, 0 );
if( hr < 0 )
Marshal.ThrowExceptionForHR( hr );

return true;
}
catch( Exception ee )
{
MessageBox.Show( this, "Could not setup graph\r\n" +
ee.Message, "DirectShow.NET", MessageBoxButtons.OK, MessageBoxIcon.Stop
);
return false;
}
}


/// <summary> create the used COM components and get the
interfaces. </summary>
bool GetInterfaces()
{
Type comType = null;
object comObj = null;
try {
comType = Type.GetTypeFromCLSID( Clsid.FilterGraph
);
if( comType == null )
throw new NotImplementedException(
@"DirectShow FilterGraph not installed/registered!" );
comObj = Activator.CreateInstance( comType );
graphBuilder = (IGraphBuilder) comObj; comObj =
null;

Guid clsid = Clsid.CaptureGraphBuilder2;
Guid riid = typeof(ICaptureGraphBuilder2).GUID;
comObj = DsBugWO.CreateDsInstance( ref clsid, ref
riid );
capGraph = (ICaptureGraphBuilder2) comObj; comObj =
null;

comType = Type.GetTypeFromCLSID( Clsid.SampleGrabber
);
if( comType == null )
throw new NotImplementedException(
@"DirectShow SampleGrabber not installed/registered!" );
comObj = Activator.CreateInstance( comType );
sampGrabber = (ISampleGrabber) comObj; comObj =
null;

mediaCtrl = (IMediaControl) graphBuilder;
videoWin = (IVideoWindow) graphBuilder;
mediaEvt = (IMediaEventEx) graphBuilder;
baseGrabFlt = (IBaseFilter) sampGrabber;
return true;
}
catch( Exception ee )
{
MessageBox.Show( this, "Could not get interfaces\r
\n" + ee.Message, "DirectShow.NET", MessageBoxButtons.OK,
MessageBoxIcon.Stop );
return false;
}
finally
{
if( comObj != null )
Marshal.ReleaseComObject( comObj ); comObj =
null;
}
}

/// <summary> create the user selected capture device.
</summary>
bool CreateCaptureDevice( UCOMIMoniker mon )
{
object capObj = null;
try {
Guid gbf = typeof( IBaseFilter ).GUID;
mon.BindToObject( null, null, ref gbf, out capObj );
capFilter = (IBaseFilter) capObj; capObj = null;
return true;
}
catch( Exception ee )
{
MessageBox.Show( this, "Could not create capture
device\r\n" + ee.Message, "DirectShow.NET", MessageBoxButtons.OK,
MessageBoxIcon.Stop );
return false;
}
finally
{
if( capObj != null )
Marshal.ReleaseComObject( capObj ); capObj =
null;
}

}



/// <summary> do cleanup and release DirectShow. </summary>
void CloseInterfaces()
{
int hr;
try {
#if DEBUG
if( rotCookie != 0 )
DsROT.RemoveGraphFromRot( ref
rotCookie );
#endif

if( mediaCtrl != null )
{
hr = mediaCtrl.Stop();
mediaCtrl = null;
}

videoInfoHeader = null;



if( mediaEvt != null )
{
hr = mediaEvt.SetNotifyWindow( IntPtr.Zero,
WM_GRAPHNOTIFY, IntPtr.Zero );
mediaEvt = null;
}

if( videoWin != null )
{
hr = videoWin.put_Visible( DsHlp.OAFALSE );
hr = videoWin.put_Owner( IntPtr.Zero );
videoWin = null;
}

baseGrabFlt = null;
if( sampGrabber != null )
Marshal.ReleaseComObject( sampGrabber );
sampGrabber = null;

if( capGraph != null )
Marshal.ReleaseComObject( capGraph );
capGraph = null;

if( graphBuilder != null )
Marshal.ReleaseComObject( graphBuilder );
graphBuilder = null;

if( capFilter != null )
Marshal.ReleaseComObject( capFilter );
capFilter = null;

if( capDevices != null )
{
foreach( DsDevice d in capDevices )
d.Dispose();
capDevices = null;
}
}
catch( Exception )
{}
}

/// <summary> resize preview video window to fill client
area. </summary>
void ResizeVideoWindow()
{
if( videoWin != null )
{
Rectangle rc = videoPanel.ClientRectangle;
videoWin.SetWindowPosition( 0, 0, rc.Right,
rc.Bottom );
}
}

/// <summary> override window fn to handle graph events.
</summary>
protected override void WndProc( ref Message m )
{
if( m.Msg == WM_GRAPHNOTIFY )
{
if( mediaEvt != null )
OnGraphNotify();
return;
}
base.WndProc( ref m );
}

/// <summary> graph event (WM_GRAPHNOTIFY) handler.
</summary>
void OnGraphNotify()
{
DsEvCode code;
int p1, p2, hr = 0;
do
{
hr = mediaEvt.GetEvent( out code, out p1, out p2, 0
);
if( hr < 0 )
break;
hr = mediaEvt.FreeEventParams( code, p1, p2 );
}
while( hr == 0 );
}

/// <summary> sample callback, NOT USED. </summary>
int ISampleGrabberCB.SampleCB( double SampleTime, IMediaSample
pSample )
{
Trace.WriteLine( "!!CB: ISampleGrabberCB.SampleCB" );
return 0;
}

/// <summary> buffer callback, COULD BE FROM FOREIGN
THREAD. </summary>
int ISampleGrabberCB.BufferCB( double SampleTime, IntPtr pBuffer,
int BufferLen )
{
if( captured || (savedArray == null) )
{
Trace.WriteLine( "!!CB:
ISampleGrabberCB.BufferCB" );
return 0;
}

captured = true;
bufferedSize = BufferLen;
Trace.WriteLine( "!!CB: ISampleGrabberCB.BufferCB !GRAB!
size = " + BufferLen.ToString() );
if( (pBuffer != IntPtr.Zero) && (BufferLen > 1000) &&
(BufferLen <= savedArray.Length) )
Marshal.Copy( pBuffer, savedArray, 0, BufferLen );
else
Trace.WriteLine( " !!!GRAB! failed " );
this.BeginInvoke( new CaptureDone( this.OnCaptureDone ) );
return 0;
}


/// <summary> flag to detect first Form appearance
</summary>
private bool firstActive;

/// <summary> base filter of the actually used video
devices. </summary>
private IBaseFilter capFilter;

/// <summary> graph builder interface. </summary>
private IGraphBuilder graphBuilder;

/// <summary> capture graph builder interface. </summary>
private ICaptureGraphBuilder2 capGraph;
private ISampleGrabber sampGrabber;

/// <summary> control interface. </summary>
private IMediaControl mediaCtrl;

/// <summary> event interface. </summary>
private IMediaEventEx mediaEvt;

/// <summary> video window interface. </summary>
private IVideoWindow videoWin;

/// <summary> grabber filter interface. </summary>
private IBaseFilter baseGrabFlt;

/// <summary> structure describing the bitmap to grab.
</summary>
private VideoInfoHeader videoInfoHeader;
private bool captured = true;
private int
bufferedSize;

/// <summary> buffer for bitmap data. </summary>
private byte[] savedArray;

/// <summary> list of installed video devices. </summary>
private ArrayList capDevices;

private const int WM_GRAPHNOTIFY = 0x00008001; // message from
graph

private const int WS_CHILD = 0x40000000; //
attributes for video window
private const int WS_CLIPCHILDREN = 0x02000000;
private const int WS_CLIPSIBLINGS = 0x04000000;

/// <summary> event when callback has finished
(ISampleGrabberCB.BufferCB). </summary>
private delegate void CaptureDone();
private void button1_Click(object sender, EventArgs e)
{
CloseInterfaces();
Dispose();
firstActive = false;
}

private void button2_Click(object sender, EventArgs e)
{
if (firstActive)
return;
firstActive = true;

if (!DsUtils.IsCorrectDirectXVersion())
{
MessageBox.Show(this, "DirectX 8.1 NOT installed!",
"DirectShow.NET", MessageBoxButtons.OK, MessageBoxIcon.Stop);
this.Close(); return;
}

if (!DsDev.GetDevicesOfCat(FilterCategory.VideoInputDevice, out
capDevices))
{
MessageBox.Show(this, "No video capture devices found!",
"DirectShow.NET", MessageBoxButtons.OK, MessageBoxIcon.Stop);
this.Close(); return;
}

DsDevice dev = null;
if (capDevices.Count == 1)
dev = capDevices[0] as DsDevice;
else
{
DeviceSelector selector = new DeviceSelector(capDevices);
selector.ShowDialog(this);
dev = selector.SelectedDevice;
}

if (dev == null)
{
this.Close(); return;
}

if (!StartupVideo(dev.Mon))
this.Close();
}

#if DEBUG
private int rotCookie = 0;


#endif
}

internal enum PlayState
{
Init, Stopped, Paused, Running
}

}