title: Hough Transform Equation
body: <p>I was wondering why the Hough Transform uses <code>rho=xcos(theta) + ysin(theta)</code> for representation of a straight line <code>(y=mx+b)</code>. I tried to work through this (and went to the <a href="http://en.wikipedia.org/wiki/Hough_transform" rel="noreferrer">wikipedia article</a> about this), but can not find a way to derive one from the other.</p>
  
  <p>Does anyone know how to derive one from the other?</p>
  
  <p>Thank you in advance.</p>