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Copy output image from TWindowsMediaPlayer

Hello,
I am trying to copy output image from a TWindowsMediaPlayer activeX component imported in C++ Builder (RAD Studio 10.1 Berlin).
I need to copy content of Windows Media Player to a Panel, Image or another component for giving customer a Preview of Player. I was trying to copy with BitBlt function, copying canvas of TPanel that contains Player, but result was always a black rect. I was supposing that Windows Media Player maybe shows output pictures in video memory and I do not know how can I copy this output.
I put a fragment of my code where I try to copy the panel containing the Player to another panel:

      HDC destino = GetDC( Panel1->Handle );
      HDC origen = GetDC( pnlInformacion->Handle );
      BitBlt(destino, 0, 0, Panel1->Width, Panel1->Height, origen, 0,0, SRCCOPY);
      ReleaseDC( Panel1->Handle, destino );
      ReleaseDC( pnlInformacion->Handle, origen );

pnlInformation contains TWindowsMediaPlayer ActiveX control.
Can you help me?

Thanks.

Merete

Hi Angel
I have no ideas on what you are referring to pnlInformation contains TWindowsMediaPlayer ActiveX control. and TWindowsMediaPlayer
so in my layman terms if you can see a video/image in this media player yu can use the snipping tool in windows 7 and windows 8 and windows 10.
It is located in your system tools> start menu> accessories
It can be used to grab a screenshot of whatever is on your desktop. The snipping tool has the options to grab a screenshot of a rectangle ( drag the curser around the area you want) that area will go grey and clear inside the area you highlight, then use the floppy to save it as??
or a full screen , or free style, if you change your mind just click new to start a new again.

snipping tool save and options

If my comment is right off or away from your more complex method hopefully my comment will bring in others.
Back to you.

Angel Martinez Gonzalvo

ASKER

Hi Merete,
I know how to use the Windows snipping tool but I want to do the same with C++ code inside my program. When I try to do this by code obtains a black rectangle where player was.

Thanks and regards.

sarabande

if you want to copy a bitmap from screen to destination device context (dc), the DC should be a Memory DC where a HBITMAP was selected into. after BitBlt copy you then could use the bitmap of the Memory DC to create a DIB (a device-independent bitmap) or to draw it into another window or even a printer.

see http://www.winprog.org/tutorial/bitmaps.html

for more information.

Sara

Angel Martinez Gonzalvo

ASKER

Hi sarabande,
first of all thanks for the info.
I have tried what you said but same result. All components were copied but TWindowsMediaPlayer:

Code used:

      Panel1->Width = pnlInformacion->Width;
      Panel1->Height = pnlInformacion->Height;
      HDC capture = GetDC( pnlInformacion->Handle );
      HDC target = CreateCompatibleDC( capture );
      int width = pnlInformacion->Width;
      int height = pnlInformacion->Height;

      HBITMAP hBitmap = CreateCompatibleBitmap( capture, width, height );

      HBITMAP hOldBitmap = (HBITMAP)SelectObject( target, hBitmap );

      BitBlt(target, 0, 0, width, height, capture, 0,0, SRCCOPY);

      hBitmap = (HBITMAP)SelectObject( target, hOldBitmap );
      Image1->Picture->Bitmap->Handle = hBitmap;

      ReleaseDC( pnlInformacion->Handle, target );
      DeleteDC( capture );
      DeleteDC( target );

As you can see I can copy all content but player.
Any idea?

Thanks.

ASKER CERTIFIED SOLUTION

sarabande

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Angel Martinez Gonzalvo

ASKER

It works!
Thank you so much sarabande!

Final code:

	Panel1->Width = pnlReproduccion->Width;
	Panel1->Height = pnlReproduccion->Height;
	HDC capture = GetDC( NULL );
	HDC target = CreateCompatibleDC( capture );
	int width = GetSystemMetrics(SM_CXVIRTUALSCREEN);
	int height = GetSystemMetrics(SM_CYVIRTUALSCREEN);

	HBITMAP hBitmap = CreateCompatibleBitmap( capture, width, height );
	HBITMAP hOldBitmap = (HBITMAP)SelectObject( target, hBitmap );

	BitBlt(target, 0, 0, pnlReproduccion->Width, pnlReproduccion->Height, capture, pnlReproduccion->Left , pnlReproduccion->Top, SRCCOPY);

	hBitmap = (HBITMAP)SelectObject( target, hOldBitmap );
	Image1->Picture->Bitmap->Handle = hBitmap;

	ReleaseDC( NULL, capture );
	ReleaseDC( NULL, target );
	DeleteDC( capture );
	DeleteDC( target );

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Regards.