title: error: (-215) _src.type() == CV_8UC1 in function equalizeHist when trying to equalize a float64 image
body: <p>I'm trying to equalize a 1 one channel image like so:</p>
  
  <pre><code>img = cv2.equalizeHist(img)
  </code></pre>
  
  <p>But since it's a float64 img, I get the following error:</p>
  
  <blockquote>
    <p>error: (-215) _src.type() == CV_8UC1 in function equalizeHist</p>
  </blockquote>
  
  <p>How do I go about this?</p>