IltmmWMScript CreateScriptStream Example for C

This example shows how to add stream scripts from a capture graph.

#define MAKE_MEDIA_PATH(pFileName) (TEXT("C:\\LEADTOOLS 20\\Media\\")TEXT(pFileName)) 
void IltmmWMScript_CreateScriptStream_Example(IltmmCapture *pCapture) 
{ 
   HRESULT hr = S_OK; 
   IUnknown *punk; 
   IltmmWMScript *pWMScript; 
    
   // source and target path names 
   BSTR bstrTarget = SysAllocString(MAKE_MEDIA_PATH("source_script.wmv")); 
    
   // set the source, target and WMV target formats for our conversion 
   hr = SelectCaptureDevices(pCapture); 
   if (FAILED(hr)) 
   { 
      MessageBox(NULL, L"Unable to select capture devices", L"WMScripting Example", MB_OK); 
      return; 
   } 
    
   IltmmCapture_put_TargetFile(pCapture, bstrTarget); 
   IltmmCapture_put_TargetFormat(pCapture, ltmmCapture_TargetFormat_WMV_Mux); 
    
   // free the BSTR 
   SysFreeString(bstrTarget); 
    
   // get the target object 
   IltmmCapture_GetSubObject(pCapture, ltmmCapture_Object_TargetFilter, &punk); 
   if (punk) 
   { 
      // get the WMScript object 
      IUnknown_QueryInterface(punk, &IID_IltmmWMScript, (void**)&pWMScript); 
      if (pWMScript) 
      { 
         WCHAR szTemp[128]; 
         double scriptTime; 
         BSTR bstrScriptCmd; 
          
         // turn off stream scripts and remove any header scripts 
         IltmmWMScript_put_EnableScriptStream(pWMScript, VARIANT_TRUE); 
         IltmmWMScript_RemoveAllHeaderScripts(pWMScript); 
          
         // create a sample header script (type of caption) and set it to execute @ 2 secs into capture 
         scriptTime = 2.0; 
         swprintf_s(szTemp, _countof(szTemp), L"Sample caption script at %g seconds", scriptTime); 
         bstrScriptCmd = SysAllocString(szTemp); 
          
         // add the header script 
         hr = IltmmWMScript_WriteScriptStream(pWMScript, L"caption", bstrScriptCmd, scriptTime); 
          
         // free the bstr 
         SysFreeString(bstrScriptCmd); 
          
         // now close the script stream 
         hr = IltmmWMScript_CloseScriptStream(pWMScript); 
         IUnknown_Release(pWMScript); 
      } 
      // if all is well, run the capture now 
      if (SUCCEEDED(hr)) 
         hr = IltmmCapture_StartCapture(pCapture, ltmmCapture_Mode_VideoAndAudio); 
       
      IUnknown_Release(punk); 
   } 
} 
 
BOOL SelectDeviceLike(IltmmDevices *pDevices, LPTSTR szDevSrch) 
{ 
   BOOL bFound = FALSE; 
   long i, count = 0; 
   IltmmDevices_put_Selection(pDevices, -1); 
   IltmmDevices_get_Count(pDevices, &count); 
   for(i = 0; i < count; i++) 
   { 
      IltmmDevice *pDevice; 
      BSTR name; 
      IltmmDevices_Item(pDevices, i, &pDevice); 
      if (pDevice) 
      { 
         // get the friendly name for comparisson check 
         IltmmDevice_get_FriendlyName(pDevice, &name); 
          
         // if the device name contains our search string, select it 
         if(!wcsstr(name, szDevSrch)) 
         { 
            IltmmDevices_put_Selection(pDevices, i); 
            IltmmDevice_Release(pDevice); 
            SysFreeString(name); 
            bFound = TRUE; 
            break; 
         } 
         SysFreeString(name); 
         IltmmDevice_Release(pDevice); 
         pDevice = NULL; 
      } 
   } 
   return bFound; 
} 
 
HRESULT SelectCaptureDevices(IltmmCapture *pCapture) 
{ 
   IltmmDevices *pDevices; 
   BOOL bSelected = FALSE; 
   IltmmCapture_get_VideoDevices(pCapture, &pDevices); 
   if (!pDevices) 
      return E_FAIL; 
       
   bSelected = SelectDeviceLike(pDevices, L"Logitech"); 
   IltmmDevices_Release(pDevices); 
   pDevices = NULL; 
   if (!bSelected) 
      return E_FAIL; 
    
   bSelected = FALSE; 
   IltmmCapture_get_AudioDevices(pCapture, &pDevices); 
   if (!pDevices) 
      return E_FAIL; 
       
   bSelected = SelectDeviceLike(pDevices, L"Logitech"); 
   IltmmDevices_Release(pDevices); 
   if (!bSelected) 
      return E_FAIL; 
       
   return S_OK; 
} 

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