C / C++ / MFC

#include <gdiplus.h>


// This function stolen from the GDI+ docs

int GetEncoderClsid(const WCHAR* format, CLSID* pClsid)
{
	UINT  num = 0;          // number of image encoders
	UINT  size = 0;         // size of the image encoder array in bytes

	ImageCodecInfo* pImageCodecInfo = NULL;

	GetImageEncodersSize(&num, &size);
	if(size == 0)
		return -1;  // Failure

	pImageCodecInfo = (ImageCodecInfo*)(malloc(size));
	if(pImageCodecInfo == NULL)
		return -1;  // Failure

	GetImageEncoders(num, size, pImageCodecInfo);

	for(UINT j = 0; j < num; ++j)
	{
		if( wcscmp(pImageCodecInfo[j].MimeType, format) == 0 )
		{
			*pClsid = pImageCodecInfo[j].Clsid;
			free(pImageCodecInfo);
			return j;  // Success
		}    
	}

	free(pImageCodecInfo);
	return -1;  // Failure
}


...

// Convert a JPEG to a BMP with GDI+

	ULONG dwToken;
	Gdiplus::GdiplusStartupInput input;
	Gdiplus::GdiplusStartupOutput output;
	Gdiplus::Status status = Gdiplus::GdiplusStartup(&dwToken, &input, &output);
	if(status == Gdiplus::Ok)
	{
		Gdiplus::Bitmap *pSrcBitmap = new Gdiplus::Bitmap(L"c:\\test.jpg", FALSE);
		CLSID bmpClsid;
		GetEncoderClsid(L"image/bmp", &bmpClsid);
		pSrcBitmap->Save(L"c:\\test.bmp", &bmpClsid);
		delete pSrcBitmap;

		Gdiplus::GdiplusShutdown(dwToken);
	}

Mark Salsbery
Microsoft MVP - Visual C++

Rajesh R Subramanian wrote:

And now he has posted a trigonometry question in the Visual C++ board.

  A
  |\
  | \
  |  \
  |   \
  |    \
  |     \
  |      \
C -------- B