title: How to open an rtp jpeg stream in opencv?
body: <p>I'm trying to open a video stream in opencv but I'm having some difficulties. I can start a stream with :</p>
  
  <pre><code>gst-launch -v v4l2src device=/dev/video0 ! 'video/x-raw-yuv,width=640,height=480' !  jpegenc quality=30 ! rtpjpegpay ! udpsink host=127.0.0.1 port=1234
  </code></pre>
  
  <p>`</p>
  
  <p>and I can open it with:</p>
  
  <pre><code>gst-launch udpsrc port=1234 ! "application/x-rtp, payload=127" ! rtpjpegdepay ! jpegdec ! xvimagesink sync=false
  </code></pre>
  
  <p>But when I tried to open it in my code with </p>
  
  <pre><code>VideoCapture cv_cap;
  cv_cap.open("rtp:127.0.0.1:1234/");
  </code></pre>
  
  <p>I get an error about a missing SDP files. I know what an SDP file is and that I should get the info for it from the gstreamer output but I don't understand exactly how to parse the output. </p>