cs window is activated, 
the user can add new borders by left-clicking the mouse along the path.
Every click draws a point representing the ring border.
Type <code><a href='../articles/detection-MtreeRing.html'>vignette('detection-MtreeRing')</a></code> to see 
an example of adding ring borders.</p>
<p>The identification process does not automatically stop by itself.</p>
<ul>
<li><p>On the Windows system, the identification process can be terminated by 
  pressing the right mouse button and selecting <b>Sto