MagSetWindowFilterList function not remove specified window of screenshot

[flashcoder]

Zitat von EWeiss:

That is hard
But as I said my code I uploaded here works.

The callback function ImageScaling is executed in your test?

Edition:

The callback is working to me now, i discovered that my callback function is executed always that Magnifier window is resized:

Delphi-Quellcode:

function MagImageScalingCallback(hwnd: hwnd; srcdata: Pointer;
  srcheader: MAGIMAGEHEADER; destdata: Pointer; destheader: MAGIMAGEHEADER;
  unclipped: TRect; clipped: TRect; dirty: HRGN): BOOL; stdcall;
var
  lpbmih: TBitmapInfoHeader;
  lpbmi: TBitmapInfo;
  aBitmap: HBITMAP;
  aDC: HDC;
  bmp: TBitmap;
begin
  Fillchar(lpbmih, SizeOf(lpbmih), 0);
  lpbmih.biSize := SizeOf(lpbmih);
  lpbmih.biWidth := srcheader.width;
  lpbmih.biHeight := srcheader.height;
  lpbmih.biPlanes := 1;
  lpbmih.biBitCount := Floor(lpbmih.biSizeImage / lpbmih.biHeight /
    lpbmih.biWidth * 8);
  lpbmih.biCompression := BI_RGB;

  Fillchar(lpbmi, SizeOf(lpbmi), 0);
  lpbmi.bmiHeader.biSize := SizeOf(lpbmi.bmiHeader);
  lpbmi.bmiHeader.biWidth := srcheader.width;
  lpbmi.bmiHeader.biHeight := srcheader.height;
  lpbmi.bmiHeader.biPlanes := 1;
  lpbmi.bmiHeader.biBitCount :=
    Floor(lpbmi.bmiHeader.biSizeImage / lpbmi.bmiHeader.biHeight /
    lpbmi.bmiHeader.biWidth * 8);
  lpbmi.bmiHeader.biCompression := BI_RGB;

  aDC := GetWindowDC(hwnd);
  bmp := TBitmap.Create;
  aBitmap := 0;
  try
    aBitmap := CreateDIBitmap(aDC, lpbmih, 0, nil, lpbmi, DIB_RGB_COLORS);
    bmp.handle := aBitmap;
    bmp.SaveToFile('c:\tela.bmp');
  finally
    DeleteObject(aBitmap);
    DeleteDC(aDC);
    bmp.Free;
  end;
  Result := True;
end;

//...

if (not MagSetImageScalingCallback(hwndMag, MagImageScalingCallback)) then

My trouble now is that i'm getting a black image. Some idea how fix?