Installing Gstreamer-1.0 on Mac OS X Mavericks

The package you have downloaded from the gstreamer website install everything under the /Library/Frameworks/ directory. The following command should work on your system:

/Library/Frameworks/GStreamer.framework/Commands/gst-launch-1.0 --version

From https://stackoverflow.com/a/30873313/1162305

Try installing them with the following commands from your terminal:

brew install gstreamer gst-plugins-base gst-plugins-good gst-plugins-bad gst-plugins-ugly gst-ffmpeg