title: Select points on image to retrieve coordinates
body: <p>I'm trying to (manually) select a section from an image and need to know the coordinates (4 points of the square) of the selected section.</p>
  
  <p>This is an Android app, I know there is a crop intent but don't want to actually crop the section, just retrieve the coordinates of the four points of the squared section.</p>
  
  <p>Any ideas?</p>
  
  <p>Much appreciated!</p>