title: Determine if a point is within ROI with OpenCV
body: <p>My objective is to determine whether a point resides within a ROI or not. I have managed to crop an ROI and can access its width and height like this</p>
  
  <pre><code>width = roi.shape[0] #total rows as width
  height = roi.shape[1] #total columns as height
  </code></pre>
  
  <p>However, I lack 2 additional variables, which are top and left coordinates in order to construct the following statement to determine whether my point exists within ROI or not.</p>
  
  <pre><code>if(top &lt; point_x &lt; top + width and left &lt; point_x &lt; left + height)
  </code></pre>
  
  <p>Appreciate your help and time, thank you.</p>