title: Assertion Failed <0 <= i && i < <int>vv.size<>> in unknown function, file src\matrix.cpp, line 912
body: <p>First of all, i'm to new to the site (but i read and cacth info from it since a long time yet :D) so sorry if i'll make some error in structuring the question...and most important, i'm new to programming (ok not new, but i started 6 months ago)..
  anyway, this is the code (the interested part):</p>
  
  <pre><code>extern DWORD miothread3 (LPDWORD lpdwParam)
  {
  
  Mat epsilon(dest);
  Mat finale;
  Mat *super;
  int ratio = 3;
  int lowThreshold;
  int kernel_size = 3;
  int i = 0;
  CvConvexityDefect convessione;
  vector&lt;vector&lt;Point&gt; &gt; contorni;
  vector&lt;Vec4i&gt; gerarchia;
  Mat hull;
  
  while(1)
  {
      Canny(epsilon, finale, lowThreshold, lowThreshold*ratio, kernel_size );
      findContours(finale, contorni, CV_RETR_LIST, CV_CHAIN_APPROX_NONE);
      convexHull(contorni, hull);
  }
  return 0;
  }
  </code></pre>
  
  <p>when i run it, i got the assertion in title ("Assertion Failed <code>&lt;0 &lt;= i &amp;&amp; i &lt; &lt;int&gt;vv.size&lt;&gt;&gt;</code> in unknown function, file src\matrix.cpp, line 912") and if i comment the line of <code>convexHull(contorni, hull);</code> it does work...
  i really cannot figure out what's the problem...so, if someone could help, would be lovable!:)</p>
  
  <p>thank you in advance, best regards.</p>