gstreamer Elements

capsfilter — pass data though unmodified, but enforces format limmits
fakesrc — Generate (meaningless) buffers
fakesink — black hole for data
fdsink — write to a unix file descriptor
fdsrc — read from a unix file descriptor
filesrc — read from arbitrary point in a file
filesink — write stream to a file
identity — pass data through without modification
queue — Simple asynchronous data queue.
tee — 1-to-N pipe fitting
typefind — Finds the media type of a stream