Introduction

When watching videos or live streams on your Steam Deck, using the Deck's hardware decoders will allow you to save CPU cycles and decrease your battery usage. However, browsers and other programs on the Deck may not use hardware decoding by default. This guide serves to demonstrate how to configure common programs to use the Video Acceleration API (VA-API) decoder on the Steam Deck.

Most of the information in this guide can also be parsed from https://wiki.archlinux.org/title/Hardware_video_acceleration

Firefox Flatpak

As of Steam OS 3.3, all installations should have been migrated to the Flatpak version of Firefox.

1. In your address bar, type about:config to access the configuration page.
2. Search for the preference gfx.webrender.all and set it to true
3. Search for the preference media.ffmpeg.vaapi.enabled and set it to true

Chromium-based Browsers (BROKEN DON'T USE)

• Note: These instructions will not affect Google Chrome within Game Mode. Currently there is a bug in XWayland that causes a stutter, so using VA-API on the Google Chrome for Game Mode is not recommended. https://bugs.archlinux.org/task/67035

• These instructions should work for all chromium-based browsers installed from Discover, such as Google Chrome, Chromium, Edge, etc. However this was tested with Ungoogled-Chromium.

Unlike Firefox where you modify the config, you must invoke Chromium with specific command line arguments. To make it easier to run Chromium with these arguments, create a custom Desktop file.

1. Copy the original desktop file from your browser into your local directory. Replace com.github.Eloston.UngoogledChromium with whatever browser you are using.

   cp /var/lib/flatpak/exports/share/applications/com.github.Eloston.UngoogledChromium.desktop ~/.local/share/applications/

2. Edit the file that you copied:

   #Exec=/usr/bin/flatpak run --branch=stable --arch=x86_64 --command=/app/bin/chromium --file-forwarding com.github.Eloston.UngoogledChromium @@u %U @@
   Exec=/usr/bin/flatpak run --branch=stable --arch=x86_64 --env=LIBVA_DRIVER_NAME=radeonsi --command=/app/bin/chromium --file-forwarding com.github.Eloston.UngoogledChromium @@u %U @@ --ignore-gpu-blocklist --enable-features=VaapiVideoDecoder --disable-features=UseChromeOSDirectVideoDecoder,UseSkiaRenderer --use-gl=egl
   

MPV (Flatpak)

MPV is a video player, not a browser. However you can use it to play youtube videos as well. This is the best way to watch videos while using the least amount of resources.

1. Install mpv using the Discover store
2. Create a file named mpv.conf in the /home/deck/.var/app/io.mpv.Mpv/config/mpv/ directory
3. Copy and paste the following into the file:

   vo=gpu
   hwdec=auto