Adding Windows Media Support to the ltmmConvert Object for C

The following code demonstrates how to add Windows Media support to the ltmmConvert Object.

// declare the windows media certificate creation function
HRESULT STDMETHODCALLTYPE WMCreateCertificate( IUnknown** pUnkCert ); 

// link the stub library
#pragma comment(lib, "wmstub.lib")


void AddWindowsMediaSupportConvertObjectExample ( void )
{
   HRESULT hr; 
   IltmmConvert* pConvert = NULL;
   IUnknown* punkCert = NULL; 


   // initialize COM library
   hr = CoInitialize(NULL); 
   if(FAILED(hr)) 
      goto error; 

   // create the convert object
   hr = CoCreateInstance(&CLSID_ltmmConvert, NULL, CLSCTX_INPROC_SERVER, &IID_IltmmConvert, (void**) &pConvert); 
   if(FAILED(hr)) 
      goto error; 

   // create windows media certificate   
   hr = WMCreateCertificate(&punkCert); 
   if(SUCCEEDED(hr)) 
   {
      // assign the certificate to the convert object
      IltmmConvert_put_WMCertificate (pConvert, punkCert); 
      IUnknown_Release(punkCert); 
   }   

error: 
   // cleanup

   if(pConvert) 
      IUnknown_Release(pConvert); 

   CoUninitialize();
}