xesite/blog/vtubing-linux-2021-01-15.markdown

title	date	series	tags
VTubing on Linux	2022-01-15	vtuber	envtuber nixos yearofthelinuxdesktop

In my last post I went through my VTubing setup on Windows and all the "generations" of setup that I've done over the last year. Thanks to the meddling of a certain nerd who is in the chat watching me write this, I have figured out a way to run this setup on Linux. The ultimate goal for this phase is to get all this running on my work laptop so I can use it for a webcam. However this post is just going to cover the Linux setup bits.

Differences Between OSes

On Windows, this setup is really straightforward. VSeeFace provides a webcam driver that makes the output of the VSeeFace app pretend to be a USB webcam. Google Meets, OBS and the like can then pick that up like it was a normal webcam. The overall flow looks like this:

This doesn't work at all on Linux though. There's no real way to get VSeeFace (a windows application that runs under Unity) to directly pretend to be a webcam at this moment.

Pedantically, you can probably get away with doing this using a combination of PipeWire, Video4Linux or some other incarnation like that, but the main point here is that VSeeFace is a Windows app and I don't think it's possible to make Linux-specific calls like that. Feel free to prove me wrong.

So, instead we need to have VSeeFace directly output to OBS. This makes the flow look something like this:

The main difference is that for some reason VSeeFace on Linux can't capture the webcam directly. This isn't an issue however because OpenSeeFace can capture the webcam and then send the face capture data directly to VSeeFace instead. Then OBS can grab VSeeFace via XComposite like normal.

There may be a way to do this in Wayland, however we haven't figured that out yet. Please let me know if you figure out a way to get this working in Wayland.

One of the major usability differences here is that OpenSeeFace has support for tracking blinking. However, at the same time my avatar opens its eyes really slowly when I do blink. There's probably a slider I need to set to make this less...horrible, but overall it does work! I don't get this on Windows, that's interesting.

Kieto, his eyes closed!

Failed Attempts

One of the biggest stumbling points was the fact that VSeeFace is distributed as a 64 bit application. Somehow my naive usage of Wine in its default config caused me to create a 32 bit Wine prefix (it was then I learned that there are such things as 32 and 64 bit prefixes and how they are mutually incompatible), which made it impossible to launch VSeeFace because Wine would reject it for being a 64 bit program.

I went through several rounds of nuking ~/.wine, trying to run it again, setting various weird environment variables, setting build overrides, it was a catastrophe.

Other people have reported that you need to use Lutris to install and use VSeeFace on Linux. This did not work. This did not work at all. Trying to do it this way on a NixOS machine was an absolute waste of my time and was demoralizing and frustrating.

I think it has to do with the fact that Lutris really really really really wants to have its own special snowflake vendored copies of Wine/Proton and it will fight you if you try to have your way otherwise.

Then I realized that I was doing all this on my work laptop. This laptop is fairly standard, but also incredibly cursed in its own unique and fun ways. It shipped with Windows, but also with all the annoying "screw you for wanting to use Linux" settings turned on. Getting to the point where a NixOS ISO would boot was an exercise in tedium and randomly flipping settings on and off.

So on the request of the aforementioned meddler, I tried running VSeeFace on my gaming tower.

It worked first try.

AAAAAA

How To Make This Creative Abomination Come To Fruition on NixOS

The easiest part of getting all this working is to download VSeeFace. You just download the .zip from the main page and extract into your Downloads folder.

Then you need to add the following to your configuration.nix file:

# ...
environment.systemPackages = with pkgs; [
    # vseeface
    wine64
    winetricks
];
# ...

Rebuild and then this will put Wine (as wine64) in your $PATH. Now you need to install the Arial font using winetricks:

$ env WINE=wine64 winetricks arial

This will take a moment to create your Wine prefix in ~/.wine and populate it with the needed fonts. VSeeFace uses the Arial font everywhere in the UI, so this is not an optional step.

Now, clone OpenSeeFace to somewhere:

$ git clone https://github.com/emilianavt/OpenSeeFace ~/tmp/OpenSeeFace

And then copy in this shell.nix file into the root of the git repo:

{ pkgs ? import <nixpkgs> { } }:
(pkgs.buildFHSUserEnv {
  name = "pipzone";
  targetPkgs = pkgs:
    (with pkgs; [
      python39
      python39Packages.pip
      python39Packages.virtualenv
      libGL
      libGLU
      glib
    ]);
  runScript = "bash";
}).env

Then run nix-shell to activate an environment that will pretend to be a normal Linux system and paste in these commands to set up the Python environment:

python -m venv .venv
source .venv/bin/activate
pip3 install onnxruntime opencv-python pillow numpy

This will install the dependencies into a python venv.

We can't really use a normal Nix packaging flow here because onnixruntime was removed from nixpkgs. This is okay though, we can hack around this!

Then you can run OpenSeeFace and you will see many lines of output:

$ python facetracker.py -c 0 -W 1280 -H 720 --discard-after 0 --scan-every 0 --no-3d-adapt 1 --max-feature-updates 900

This will show many lines that look something like this:

Took 20.50ms (detect: 0.00ms, crop: 0.82ms, track: 17.70ms, 3D points: 1.93ms)
Confidence[0]: 0.9148 / 3D fitting error: 12.7974 / Eyes: O, O

This dumps most of the internal state of the face tracking algorithm. VSeeFace will pick up on this and then turn that into movement instructions for your waifu.

Finally you can make an XComposite capture in OBS and then use that to get things through to Twitch that way.

Nice Wrapper Script

All these instructions are lame, I just wanna get it done fast!

You can get this all running with a super hacky script like this!

#!/usr/bin/env nix-shell
#! nix-shell -p wget -p git -p winetricks -p wine64 -i bash

mkdir -p ~/tmp/VTubing
cd ~/tmp/VTubing

wget https://github.com/emilianavt/VSeeFaceReleases/releases/download/v1.13.37b/VSeeFace-v1.13.37b.zip
unzip VSeeFace-v1.13.37b.zip

WINE=wine64 winetricks arial

git clone https://github.com/emilianavt/OpenSeeFace

(cd OpenSeeFace && wget -O shell.nix https://gist.githubusercontent.com/Xe/d739fd94c81c1690645c8f4607058488/raw/100c8c5e43ed8dc4b19b890173234ff28b0f9c7e/shell.nix | base64 -d > shell.nix && nix-shell) &
(cd VSeeFace && wine64 VSeeFace.exe) &

wait

This will get you everything set up and ready to go in a flash! No warranty.

You should really do this automagically with Nix.

Yes, I should, but that is for another day. This day is not today.

---

I'm really glad that I have this working on Linux though. I feel really bad about being known as a Linux enthusiast but then all of my streams are visibly using Windows. It's totally valid to want to start out on Windows because it's easier though. This stuff is baroque and complicated. Hopefully this will make the path a bit clearer if you want to do VTubing on Linux like I am.

This article was written live on Twitch! Check out the stream vod here, and in a few days it will be live on YouTube here. Follow my channel and get notified when I go live with more writing.