gst-launch-1.0

The command gst-launch-1.0 works as the GStreamer launcher for building pipelines quickly.

The following code block shows an example of generating a video by videotestsrc, and play it through xvimagesink.
gst-launch-1.0 videotestsrc ! xvimagesink

The command is part of the standard GStreamer command line tools, see GStreamer Official Documentation for more information on how to use the command.