title: installing opencv 2.4.9 on ubuntu 18.04
body: <p>I have ubuntu 18.04 installed on my pc and I managed to install the newest version of opencv. <strong>Nevertheless, I need an older version of opencv running on my pc, namely opencv-2.4.9.</strong> So I deinstalled the new version of opencv, in order to install the old version. I followed like any instruction, which I could find so far in the internet, but unfortunately all of them were actually prepared for ubuntu 14.04 or earlier, so none of them worked.
  So without going further into the details of those instructions, I would like to ask you, whether there you know of any possibility to install opencv-2.4.9 on ubuntu 18.04 (LTS)?</p>
  
  <p>Best regards,
  lonewolf</p>