webcam-filters

Add filters (background blur, etc) to your webcam on Linux.

Video conferencing applications tend to either lack video effects altogether or support only a limited set of capabilities on Linux (e.g. Zoom [1], Google Meets [2]).

Goal here is to provide a virtual webcam via v4l2loopback with a common set of filters that can be used everywhere.

• Usage
• Dependencies
  • v4l2loopback
  • Gstreamer
• Installation
  • Nix
    • Hardware Acceleration
  • Pipx/Pip
  • Docker

Usage

Passthrough (no-op):

$ webcam-filters --input-dev /dev/video0 --output-dev /dev/video3

Blur background:

$ webcam-filters --input-dev /dev/video0 --output-dev /dev/video3 --background-blur 150

Hardware acceleration (via VAAPI):

$ webcam-filters --input-dev /dev/video0 --output-dev /dev/video3 --background-blur 150 --hw-accel-api vaapi

Using docker:

$ docker run -it \
  --device=/dev/video0:/input-dev \
  --device=/dev/video3:/output-dev \
  ghcr.io/jashandeep-sohi/webcam-filters:master --background-blur 50

Dependencies

Other than the Python dependencies that can be automatically installed by Pip, there are a few system dependencies that require manual attention.

v4l2loopback

v4l2loopback kernel module is required to emulate a virtual webcam. See your distro's docs or v4l2loopback on how to install and set it up (e.g. https://archlinux.org/packages/extra/any/v4l2loopback-dkms/).

You'll probably want to create at least one loopback device (that's persistent on boot):

$ sudo tee /etc/modprobe.d/v4l2loopback.conf << "EOF"
# /dev/video3
options v4l2loopback video_nr=3
options v4l2loopback card_label="Virtual Webcam"
options v4l2loopback exclusive_caps=1
EOF
$ sudo modprobe v4l2loopback
$ v4l2-ctl --device /dev/video3 --info

Gstreamer

• gstreamer-1.0 (e.g. https://archlinux.org/packages/extra/x86_64/gstreamer/)
• gst-python (e.g. https://archlinux.org/packages/extra/x86_64/gst-python/)
• gst-plugins-base (e.g. https://archlinux.org/packages/extra/x86_64/gst-plugins-base/)
• gst-plugins-good (e.g. https://archlinux.org/packages/extra/x86_64/gst-plugins-good/)
• Optional:
  • gstreamer-vaapi for hardware acceleration (e.g. https://archlinux.org/packages/extra/x86_64/gstreamer-vaapi/)

Installation

Nix

The provided Nix package bundles all the necessary GStreamer dependencies and should "just work" on any distro.

Install a specific release version/tag:

$ nix --experimental-features 'nix-command flakes' \
    profile
    install
    github:jashandeep-sohi/webcam-filters/vx.x.x

Install a specific branch (e.g. master):

$ nix --experimental-features 'nix-command flakes' \
    profile
    install
    github:jashandeep-sohi/webcam-filters/master

Hardware Acceleration

For VAAPI support with Nix on non-NixOS systems use nixGL:

$ nix-env \
    --file https://github.com/guibou/nixGL/archive/main.tar.gz \
    --install \
    --attr auto.nixGLDefault \
    --arg enable32bits false
$ export LIBVA_DRIVER_NAME=iHD # Or whatever works with your GPU
$ nixGL webcam-filters --input-dev /dev/video0 --output-dev /dev/video3 --hw-accel-api vaapi

On NixOS follow https://nixos.wiki/wiki/Accelerated_Video_Playback

Pipx/Pip

You can also use pipx or pip. Pipx is recommend to keep Python dependencies isolated. Keep in mind this will not install gst-python or any of the other GStreamer dependencies, so you'll have to install that yourself.

Latest stable:

$ pipx install --system-site-packages webcam-filters
$ # Or
$ pip install --user webcam-filters

Latest pre-release:

$ pipx install --system-site-packages --pip-args='--pre' webcam-filters
$ # Or
$ pip install --user --pre webcam-filters

Git:

$ url="git+https://github.com/jashandeep-sohi/webcam-filters.git"
$ pipx install --system-site-packages "$url"
$ # Or
$ pip install --user "$url"

Docker

The docker container wraps a Nix installation for those who prefer to have it dockerized.

You can retag the image locally if you don't want to refer to the long name:

$ docker tag ghcr.io/jashandeep-sohi/webcam-filters:master webcam-filters

You may also build the image locally:

$ nix --experimental-features 'nix-command flakes' run .#container.copyToDockerDaemon

[1]	Zoom desktop client supports background blur as of version 5.7.6. Zoom on web does not.

[2]	Google Meets supports background blur only on Chrome.