title: OpenCV FileStorage how to read vector of structures?
body: <p>I write vector with some data like this:</p>
  
  <pre><code>string filename= itemName+".yml";
  
  FileStorage fs(filename, FileStorage::WRITE);
  fs &lt;&lt; "number_of_objects" &lt;&lt; (int)vec.size();
  fs &lt;&lt; "objects" &lt;&lt; "[";
  for( int i=0; i &lt; (int)vec.size(); ++i )
  {
      fs &lt;&lt; "{";
      fs &lt;&lt; "x" &lt;&lt; rc.x/imageScale;
      fs &lt;&lt; "y" &lt;&lt; rc.y/imageScale;
      fs &lt;&lt; "w" &lt;&lt; rc.width/imageScale;
      fs &lt;&lt; "h" &lt;&lt; rc.height/imageScale;
      fs &lt;&lt; "}";
  }
  fs &lt;&lt; "]";
  </code></pre>
  
  <p>But I can't read them back.</p>
  
  <pre><code>FileStorage fs(filename, FileStorage::READ);
  
  if(!fs.isOpened())
      return false;
  
  int nObjects= 0;
  fs["number_of_objects"] &gt;&gt; nObjects;
  imageMarkupData.resize(nObjects);
  for( int i=0; i &lt; nObjects; ++i )
  {
      int x,y,w,h;
      fs["x"] &gt;&gt; x;
      fs["y"] &gt;&gt; y;
      fs["w"] &gt;&gt; w;
      fs["h"] &gt;&gt; h;
  
      //...
  }
  </code></pre>
  
  <p>What is the proper way?</p>