title: Convert video to WebM using GStreamer
body: <p>Documentation for <em>GStreamer</em> is confusing. This is still no excuse for resorting to <em>StackOverflow.com</em>, but still:</p>
  
  <p>What is the <em>GStreamer</em> command line to convert any video file (from any format) to WebM (+WebM audio)?</p>
  
  <p><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-good-plugins/html/gst-plugins-good-plugins-webmmux.html" rel="noreferrer">This is the only documentation with examples I could find</a>.</p>
  
  <p>I'm stuck somewhere at <code>gst-launch-0.10 webmmux name=mux ! filesrc location=oldfile.ext ! filesink location=newfile.webm ! name=demux ! demux. ! ffmpegcolorspace ! vp8enc ! queue ! mux.video_0 ! demux. ! progressreport ! audioconvert ! audiorate ! vorbisenc ! queue ! mux.audio_0</code></p>
  
  <p>I'm getting a <code>WARNING: erroneous pipeline: link without source element</code> with no idea how to to get this thing going.</p>
  
  <p>This is pretty frustrating.</p>
  
  <p>Please help, thank you. :)</p>