IltmmWMScript HeaderScripts Example for C++

This example shows how to add and remove header scripts from a convert graph.

#define MAKE_MEDIA_PATH(pFileName) (TEXT("C:\\LEADTOOLS 20\\Media\\")TEXT(pFileName)) 
void ManageHeaderScripts(IltmmConvert* pConvert) 
{ 
   HRESULT hr = S_OK; 
   IUnknown *punk; 
   IltmmWMScript *pWMScript; 
   // source and target path names 
   BSTR bstrSource = SysAllocString(MAKE_MEDIA_PATH("source.avi")); 
   BSTR bstrTarget = SysAllocString(MAKE_MEDIA_PATH("source_script.wmv")); 
   // set the source, target and WMV target formats for our conversion 
   pConvert->put_SourceFile(bstrSource); 
   pConvert->put_TargetFile(bstrTarget); 
   pConvert->put_TargetFormat(ltmmConvert_TargetFormat_WMV_Mux); 
   // free the BSTRs 
   SysFreeString(bstrSource); 
   SysFreeString(bstrTarget); 
   // get the target object 
   pConvert->GetSubObject(ltmmConvert_Object_TargetFilter, &punk); 
   if (punk) 
   { 
      // get the WMScript object 
      punk->QueryInterface(IID_IltmmWMScript, (void**)&pWMScript); 
      if (pWMScript) 
      { 
         double duration; 
         long lScriptCnt; 
         WCHAR szTemp[128]; 
         double scriptTime; 
         BSTR bstrScriptType, bstrScriptCmd; 
         // turn off stream scripts and remove any header scripts 
         pWMScript->put_EnableScriptStream(VARIANT_FALSE); 
         pWMScript->RemoveAllHeaderScripts(); 
         // get the source duration 
         hr = pConvert->get_Duration(&duration); 
         if (FAILED(hr)) 
            duration = 0.5 ;//assume a relatively small duration 
         // create a sample header script (type of caption) and set it to execute @ 0 secs 
         // we will delete this one later for demonstation purposes 
         scriptTime = 0.; 
         swprintf_s(szTemp, _countof(szTemp), L"Sample caption script at %g seconds", scriptTime); 
         bstrScriptCmd = SysAllocString(szTemp); 
         // add the header script 
         hr = pWMScript->AddHeaderScript(L"caption", bstrScriptCmd, scriptTime); 
         // free the BSTR 
         SysFreeString(bstrScriptCmd); 
         // create a sample header script (type of caption) and set it to execute @ duration / 2 
         scriptTime = duration/2.0; 
         swprintf_s(szTemp, _countof(szTemp), L"Sample caption script at %g seconds", scriptTime); 
         bstrScriptCmd = SysAllocString(szTemp); 
         // add the header script 
         hr = pWMScript->AddHeaderScript(L"caption", bstrScriptCmd, scriptTime); 
         // free the BSTR 
         SysFreeString(bstrScriptCmd); 
         // now get the header script count, should be 2 from above 
         hr = pWMScript->get_HeaderScriptCount(&lScriptCnt); 
         if (SUCCEEDED(hr) && lScriptCnt>0) 
         { 
            long i; 
            // iterate through the script indexes 
            for (i=0; i<lScriptCnt; i++) 
            { 
               if (i==0) // if first one, delete it (demonstration purposes) 
               { 
                  pWMScript->RemoveHeaderScript(i); 
               } 
               else if (i==1) // if second one, just get it and display a msg box with properties 
               { 
                  hr = pWMScript->GetHeaderScript(i, &bstrScriptType, &bstrScriptCmd, &scriptTime); 
                  if (SUCCEEDED(hr)) 
                  { 
                     WCHAR szTemp[255]; 
                     swprintf_s(szTemp, _countof(szTemp), L"type: %s\ncmd: %s\ntime: %g", bstrScriptType, bstrScriptCmd, scriptTime); 
                     ::MessageBox(NULL, szTemp, L"Script Properties", MB_OK); 
                     // free the BSTRs 
                     SysFreeString(bstrScriptType); 
                     SysFreeString(bstrScriptCmd); 
                  } 
               } 
            } 
         } 
         // release the ASF mux script interface 
         pWMScript->Release(); 
      } 
      // release the target filter 
      punk->Release(); 
      // if all is well, run the convert now 
      if (SUCCEEDED(hr)) 
         hr = pConvert->StartConvert(); 
   } 
} 

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