LWia::IsVideoPreviewAvailable

L_INT LWIA__IsVideoPreviewAvailableExample() 
{ 
   LWia MyClass; 
   L_TCHAR szSavedFileName[MAX_PATH]; 
   lstrcpy(szSavedFileName,MAKE_IMAGE_PATH(TEXT(""))); 
   L_TCHAR szImagesDirectory[MAX_PATH] ; 
   lstrcpy(szImagesDirectory,MAKE_IMAGE_PATH(TEXT(""))); 
   L_TCHAR szMsg[MAX_PATH] = TEXT(""); 
   L_BOOL bAvailable = FALSE; 
   L_SIZE_T uLength = MAX_PATH; 
   IWiaItem * pRootItem = NULL; 
   L_INT nRet; 
 
   /* Select video streaming device first */ 
   nRet = MyClass.SelectDeviceDlg(WiaDeviceTypeStreamingVideo, L_WIA_SELECT_DEVICE_NODEFAULT); 
   if(nRet != WIA_SUCCESS) 
      return nRet; 
 
   nRet = MyClass.StartVideoPreview(FALSE); 
   if (nRet != WIA_SUCCESS) 
      return nRet; 
 
   bAvailable = MyClass.IsVideoPreviewAvailable(); 
   if(!bAvailable) 
   { 
      MessageBox(NULL,  
                 TEXT("No streaming video available, please call MyClass.StartVideoPreview first"), 
                 TEXT("ERROR"), 
                 MB_OK | MB_ICONERROR); 
 
      MyClass.EndVideoPreview(); 
      return FALSE; 
   } 
 
   /* Resize the video preview area to fit the parent window */ 
   // I am calling this resize function here only for demonstration purposes, but you 
   // should call it in your window resize event. 
   nRet = MyClass.ResizeVideoPreview(TRUE); 
   if(nRet != WIA_SUCCESS) 
      return nRet; 
 
   nRet = MyClass.AcquireImageFromVideo(szSavedFileName, &uLength); 
   if(nRet != WIA_SUCCESS && nRet == ERROR_BUFFER_TOO_SMALL) 
   { 
      MyClass.EndVideoPreview(); 
      nRet = MyClass.GetRootItem(NULL, (L_VOID**)&pRootItem); 
      if(nRet != WIA_SUCCESS) 
         return FALSE; 
 
      nRet = MyClass.GetPropertyString(pRootItem, NULL, WIA_DPV_IMAGES_DIRECTORY, szImagesDirectory, &uLength); 
      if(nRet == WIA_SUCCESS) 
      { 
         wsprintf(szMsg,  
            TEXT("Provided string buffer is too small to be updated.\n") 
            TEXT("But still an image was saved to the following directory:\n\n%s"), 
            szImagesDirectory); 
 
         MessageBox(NULL, szMsg, TEXT("ERROR"), MB_OK | MB_ICONERROR); 
      } 
 
      return FALSE; 
   } 
 
   wsprintf(szMsg,  
      TEXT("Captured still image was saved to the following path:\n\n%s"), 
      szSavedFileName); 
 
   MessageBox(NULL, szMsg, TEXT("Captured Image Path"), MB_OK | MB_ICONINFORMATION); 
 
   MyClass.EndVideoPreview(); 
   return SUCCESS; 
}