Gnome 3.10 ScreenCast + Audio on Arch

Question

I'm trying to record my desktop (including audio) in Gnome 3.10 on Arch Linux with the built-in screen recorder (Ctrl+Alt+Shift+R). According to this post (and other similar solutions that can be found on the Internet), I've tried to apply the gconf settings

gsettings set org.gnome.shell.recorder pipeline "queue ! videorate ! vp8enc quality=10 speed=2 ! mux. pulsesrc ! audio/x-raw-int ! queue ! audioconvert ! vorbisenc ! mux. webmmux name=mux"

but I get the following error:

No such schema 'org.gnome.shell.recorder'

Browsing with dconf-editor I see that org.gnome.shell.recorder actually is not there and I couldn't find anything similar... How can I record my desktop in gnome shell 3.10 including internal audio (not mic)?

EDIT: Also I would like not to include mouse cursor while recording.

Answer 1

That key/schema was removed in gnome-shell ≥ 3.10 so the solutions you found on the internet no longer work.
Ray Strode, gnome dev¹:

I've had a couple of people ask me if there's a way to do this in gnome-shell 3.10 and later and I haven't had a good answer. It's complicated by the fact that g-s-d now handles starting things and the org.gnome.shell.recorder schema has gone away.

Ray's suggestion there (assign a shortcut to that gjs command) is quite cool but his one liner is missing some js stuff. I had to replace the %T in threads=%T with a number (e.g. 2) to make it work. Also, note the resulting .webm file name has no time stamp so subsequent runs will overwrite the existing one if you don't rename it. Finally, make sure your XDG_VIDEOS_DIR is defined in ~/.config/user-dirs.dirs otherwise the command won't work (errors out with cannot open output file).
Anyway, back to your question, screen casting parameters are now hard-coded in gnome-shell (shell-recorder.c) e.g.:

#define DEFAULT_PIPELINE "vp9enc min_quantizer=13 max_quantizer=13 cpu-used=5 deadline=1000000 threads=%T ! queue ! webmmux"

or

shell_recorder_init (ShellRecorder *recorder)
{
....
recorder->draw_cursor = TRUE;

and as far as I can tell, the only way to alter them would be via an extension like

EasyScreenCast

(source code here) which allows you to customize all settings (including draw-cursor). It works fine, I only had to add my gnome-shell version e.g. 3.16.1 - to metadata.json and this custom gstreamer pipeline:

vp8enc  min_quantizer=10 max_quantizer=10 cpu-used=2 deadline=1000000  threads=2 ! queue ! mux. pulsesrc ! queue !  audioconvert ! vorbisenc ! queue ! mux. webmmux name=mux

via Tweak-tool > Extensions > Easyscreencast > Screencast options:

---

That aside, a trivial way to screencast + internal audio is via command line. All you need is to specify the input source for sound recording - either with pacmd (cli) or with pavucontrol (gui) and use gst-launch to record. So, first get the input source name ending with .monitor (that one can record audio from your sound card):

pacmd list-sources | sed -n 's/name: <\(.*\.monitor\)>/\1/p'
    alsa_output.pci-0000_00_1b.0.analog-stereo.monitor

and then run:

pacmd set-default-source "alsa_output.pci-0000_00_1b.0.analog-stereo.monitor"
gst-launch-1.0 ximagesrc ! videoconvert ! queue ! videorate ! vp8enc  min_quantizer=10 max_quantizer=10 cpu-used=2 deadline=1000000  threads=2 ! queue ! mux. pulsesrc ! queue !  audioconvert ! vorbisenc ! queue ! mux. webmmux name=mux ! filesink location=screencast.webm

To stop recording, switch back to terminal and hit Ctrl+C.

---

^{1: source}

Answer 2

Based on don_crissti answer, I have created a bash script for automating this task.

Here is the script:

#!/bin/bash

if [ -z $1 ]; then
    echo "usage: screencast <outfile>"
    exit 1
fi

fname=$1
audio=$(pacmd list-sources | sed -n 's/\s*name: <\(.*\.monitor\)>/\1/p')

pacmd set-default-source "$audio"

echo "Screencast started, to stop it come back to terminal and hit ctrl+c..."

gst-launch-1.0 ximagesrc \
    ! videoconvert \
    ! queue \
    ! videorate \
    ! vp8enc  min_quantizer=10 max_quantizer=10 cpu-used=2 deadline=1000000  threads=2 \
    ! queue \
    ! mux. pulsesrc \
    ! queue \
    !  audioconvert \
    ! vorbisenc \
    ! queue \
    ! mux. webmmux name=mux \
    ! filesink location=$fname > /dev/null

echo
echo "Screencast saved as $fname"

Usage:

$ ./screencast out_file_name.webm

All credits go to don_crissti. Please vote its answer!