title: MATLAB vision library shapes function
body: <p>The Lane departure system in MATLAB 2011 demos for Computer Vision toolbox has the following function.</p>
  
  <pre><code>hShapeIns1 = vision.ShapeInserter( ...
                  'Shape', 'Polygons', ...
                  'Fill', true, ...
                  'FillColor', 'Custom', ...
                  'CustomFillColor', [1 0 0], ...
                  'Antialiasing', false, ...
                  'Opacity', 1);
  </code></pre>
  
  <p>The hShapIns1 object is used to draw a polygon within the Hough lines and captures the road area. If you see the matlab product help for vision.ShapeInserter function, the shapes that can be inserted are polygons, rectangles and lines.</p>
  
  <p>My problem is that I want to insert a line parallel to the Hough lines, using the above code. But when I replace 'Polygons' with 'Lines' it doesn't work. How can I achieve this?</p>