// HWND o_hwnd  - handle to current window
 // import       - retrieves content of specified file 

 ICONINFO _iconInfo;

 PBITMAPFILEHEADER _pBmpFileHeader = (PBITMAPFILEHEADER)import("image.BMP");

 _iconInfo.hbmpColor = CreateDIBitmap (
   GetDC(o_hwnd),
   (PBITMAPINFOHEADER)(_pBmpFileHeader + 0x01),
   0x04,
   ((void*)_pBmpFileHeader)+_pBmpFileHeader.offBits,
   (PBITMAPINFO)(_pBmpFileHeader + 0x01),
   0
 );
     
 PBITMAPFILEHEADER _pMskFileHeader = (PBITMAPFILEHEADER)import("mask.BMP");

 _iconInfo.hbmpMask = CreateDIBitmap (
   GetDC(o_hwnd),
   (PBITMAPINFOHEADER)(_pMskFileHeader + 0x01),
   0x04,
   ((void*)_pMskFileHeader)+_pBmpFileHeader.offBits,
   (PBITMAPINFO)(_pMskFileHeader + 0x01),
   0
 );
                 
 _iconInfo.icon = TRUE;

 HICON _hIco = CreateIconIndirect(&_iconInfo);
 SendMessage(o_hwnd, WM_SETICON, 0, (LPARAM)_hIco);