gnome-shell recorder and pipeline

[johnny cravatta <sitiwebxtutti gmail com>]

in these days i'm searching the web to find wich command starts when
we press the keybindings ctrl+alt+shift+r to make screencast,
my research fail i can not find,
i'm not a coder only a gnome-shell user.

i like to know how screencast work,
because in my setup for the recorder i have inserted this pipeline:
queue ! videorate ! vp8enc
quality=8 speed=6  threads=%T ! mux. pulsesrc ! audio/x-raw-int !
queue ! audioconvert !
vorbisenc ! mux. webmmux name=mux

and with pavucontrol i can better understand how gnome-shell recorder
capture audio and from.

Now with this setting my audio and video works fine, but when i stop the
 screencast i can view in pavucontrol the "gnome shell record stream
from" is active,..
if i restart the screencast, a new "volume control shell record is
opened", but no sound has been keeped.

to make another audio/video screencast i do  alt+F2 r,....

with this, all last gnome-shell audio recorder volume was killed....

in substance i want to start and stop screencast, kill the gnome-shell
audio recorder with personal script or launchers, without restarting
the gnome shell


how to find the command...

sorry for my bad english,

you can view my screencast settings here:
http://www.ilceramista.com/ubublogger/?p=1013

regards, johnny cravatta