title: How do I install opencv using pip?
body: <p>I need to install <code>cv2</code> for a script that has been written for me. I tried  <code>pip install cv2</code> and <code>pip install open_cv</code> and got the same problem - a warning message from <code>dist.py</code> and complains about <code>zlib</code> being not found. No cv2 installed. I also tried <code>pyopenvc</code> and <code>pip install opencv-python</code>.</p>
  
  <p>So, I went to the opencv site and downloaded the relevant exe. Ran it - generated a heap of subdirectories and a make file and stuff. </p>
  
  <p>What do I do now?</p>