steamdeck-setup-ssh-and-gstreamer

First time, you need setup password to your deck user via passwd command under deck user:
passwd

Second time, you need launch this set of commands under root(which means, after "sudo su -" command):
steamos-readonly disable
pacman-key --init
pacman-key --populate archlinux holo
pacman -Syy
pacman -S screen gstreamer-vaapi gst-plugin-pipewire --noconfirm
systemctl enable sshd
steamos-readonly enable

Reboot of deck.

Then ssh to IP of your deck from other device to the deck user with your password.

Create file called "record" for example, with this content:

#!/bin/bash
date_var=$(date "+%Y-%m-%d %H:%M")
gst-launch-1.0 -e \
    pipewiresrc do-timestamp=True \
        ! queue \
        ! videoconvert \
        ! queue \
        ! vaapih264enc \
        ! h264parse \
        ! mux. \
    pulsesrc device="alsa_output.pci-0000_04_00.5-platform-acp5x_mach.0.HiFi__hw_acp5x_1__sink.monitor" \
        ! queue \
        ! mux. \
    matroskamux name=mux \
        ! filesink location=/home/deck/Videos/"$date_var".mkv



________________________

Make file executable:
chmod +x record


For record, its best way do it from root user screen session, because SteamOS have some mechanism to kill user processes, when user os not logged(when SSH simply drop, you are f**ked)
So from your deck user, log as root:
sudo su -


Then run screen session:
screen

In this screen session, ssh to deck@localhost via ssh "deck@localhost" command
And here, you can simply run record command like:

./record


When ssh drops, you can simply resume your screen session via:
ssh deck@deck.ip.addr.ess
sudo su -
screen -Lrd


When you want disable record, you simply press ctrl+c.

This is very simple instructions, i cannot handle every situation, what can happen.

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