title: face features from kinect v2 in 3D coordinate
body: <p>I'm working with kinect v2 and I want to record the 5 points of the face features (i.e. the location of the eyes, the nose and the mouth), but I have noticed that the points that I have got are in the color space coordinates (2D) and not in the camera space coordinates (3D).
  I tried to map the points from 2D to 3D using the following C# code:</p>
  
  <pre><code>_sensor.CoordinateMapper.MapColorFrameToCameraSpace(depthFrameArray, cameraSpacePoints);
  foreach (PointF pointF in result.FacePointsInColorSpace.Values)
  {
      CameraSpacePoint csp;
      long colorIndex = (long)((pointF.Y + 0.5f) * 1920 + (pointF.X + 0.5f));                                                           
      csp.X = cameraSpacePoints[colorIndex].X;
      csp.Y = cameraSpacePoints[colorIndex].Y;
      csp.Z = cameraSpacePoints[colorIndex].Z;
  }
  </code></pre>
  
  <p>where depthFrameArray is the depth frame arranged in an array.
  The code doesn't work for me. Do you know how to do that?
  thanks.</p>