title: What are Canny thresolds?
body: <p>Is it possible to make <a href="http://docs.opencv.org/modules/imgproc/doc/feature_detection.html?highlight=canny#canny" rel="nofollow noreferrer">Canny</a> to ignore short edges or to ignore low gradient edges? In my case I have card lying on wood and see numerous edges of wood structure after canny</p>
  
  <p><img src="https://i.stack.imgur.com/xpfC7.jpg" alt="enter image description here"></p>
  
  <p>What two thresholds in canny functions are for?</p>