Am using Ubuntu(14.04) and I am getting this error while trying to use gstreamer.
gst-launch-1.0 v4l2src ! video/x-raw,width=640,height=480 ! x264enc ! h2
I'm using a gstreamer-1.0 on Raspberry and I was having the same issue. As I was running out of options I've tried to install also the 0.10 plugins and unexpectedly it works.
sudo apt-get install gstreamer0.10-plugins-good
my 2 cent ^_^
EDIT: Well, actually it doen't work yet, but at least it's giving me a different error :)
EDIT 2: It was a syntax error, It actually works for me :)