L_WiaIsVideoPreviewAvailable

L_INT WiaIsVideoPreviewAvailableExample(HWIASESSION hSession, HWND hWnd) 
{ 
   L_TCHAR szSavedFileName[MAX_PATH] = TEXT(""); 
   L_TCHAR szImagesDirectory[MAX_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 = L_WiaSelectDeviceDlg(hSession, hWnd, WiaDeviceTypeStreamingVideo, L_WIA_SELECT_DEVICE_NODEFAULT); 
   if(nRet != WIA_SUCCESS) 
      return nRet; 
 
   nRet = L_WiaStartVideoPreview(hSession, hWnd, FALSE); 
   if (nRet != WIA_SUCCESS) 
      return nRet; 
 
   bAvailable = L_WiaIsVideoPreviewAvailable(hSession); 
   if(!bAvailable) 
   { 
      MessageBox(hWnd,  
         TEXT("No streaming video available."), 
         TEXT("ERROR"), 
         MB_OK | MB_ICONERROR); 
 
      L_WiaEndVideoPreview(hSession); 
      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 = L_WiaResizeVideoPreview(hSession, TRUE); 
   if(nRet != WIA_SUCCESS) 
      return nRet; 
 
   nRet = L_WiaAcquireImageFromVideo(hSession, szSavedFileName, &uLength); 
   if(nRet != WIA_SUCCESS && nRet == ERROR_BUFFER_TOO_SMALL) 
   { 
      L_WiaEndVideoPreview(hSession); 
      nRet = L_WiaGetRootItem(hSession, NULL, (L_VOID**)&pRootItem); 
      if(nRet != WIA_SUCCESS) 
         return FALSE; 
 
      nRet = L_WiaGetPropertyString(hSession, 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(hWnd, 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(hWnd, szMsg, TEXT("Captured Image Path"), MB_OK | MB_ICONINFORMATION); 
 
   L_WiaEndVideoPreview(hSession); 
   return SUCCESS; 
}