title: Converting from VectorOfPoint to VectorOfPointF for contours in Emgu
body: <p>I am trying to find the convex hull of a contour with emgu 3.1</p>
  
  <p>It seems to be the case that FindContours only accepts a vectorOfVectorOfPoints (not pointsF). But then, convexhull requires a vectorOfPointF. Am I wrong? If I change contours to VectorOfVectorOfPointF I get a runtime error in the call to FindContours.</p>
  
  <p>How do you convert a VectorOfPoint to VectorOfPointF?
  Is there a better way to do it?</p>
  
  <p>Thanks!</p>
  
  <pre><code>using (var contours = new VectorOfVectorOfPoint())
  using (Mat hierachy = new Mat())
  {
  
      CvInvoke.FindContours(img, contours, hierachy, Emgu.CV.CvEnum.RetrType.External, Emgu.CV.CvEnum.ChainApproxMethod.ChainApproxSimple, new Point());
              for (int i = 0; i &lt; contours.Size; i++)
              {
                  var contour = contours[i];
                  var c = new VectorOfPointF();
                  CvInvoke.ConvexHull(contour, c, false, true);
              }
  </code></pre>