OBS Plugin

An OBS Studio plugin for publishing and consuming MoQ streams.

Work in Progress

This plugin is currently under development, but works pretty gud.

Overview

The OBS plugin allows you to:

• Publish directly from OBS to a MoQ relay
• Subscribe to MoQ broadcasts as an OBS source

It loads into a stock OBS Studio install. You no longer need to build OBS from source to use it.

Building

The plugin lives in-tree under cpp/obs/. It links libmoq, which is built from the in-tree rs/libmoq crate via cargo (CMake's MOQ_LOCAL points at the repo root by default), so there is no prebuilt release to download.

Linux (Nix)

libobs, Qt6, and ffmpeg come from the dev shell; no system packages required.

nix develop
just obs build

macOS

The macOS build is fully native, not Nix. The build spec (cpp/obs/buildspec.json) downloads the prebuilt obs-deps bundle (libobs, Qt6, and ffmpeg) on first configure, so no Homebrew packages are needed.

Requirements:

• Full Xcode (not just the Command Line Tools): sudo xcode-select -s /Applications/Xcode.app
• Run outside the Nix dev shell. The Nix toolchain sets DEVELOPER_DIR/NIX_LDFLAGS, which break the Xcode build. If you use direnv, run from a plain terminal or exit the shell first.

just obs setup   # downloads obs-deps, configures via the macOS preset
just obs build
just obs run     # copies the plugin into ~/Library/Application Support/obs-studio/plugins and launches OBS

Windows

Needs Visual Studio 2022. Run from Git Bash (for just); the build spec downloads obs-deps the same way as macOS.

just obs setup
just obs build

Releases

The plugin statically links libmoq, so it ships with every libmoq release rather than on its own schedule. The libmoq workflow (triggered by a libmoq-v* tag) rebuilds the plugin against the libmoq release it just published, then cuts a matching obs-moq-v<version> release with macOS (arm64) and Windows (x64) binaries. cpp/obs/build.sh --libmoq-release <version> drives each build (it fetches the prebuilt libmoq archive, so no second cargo build).

The archives are unsigned, so macOS Gatekeeper and Windows SmartScreen will warn on first load (right-click → Open on macOS). Extract the archive into your OBS plugins directory: the .plugin bundle on macOS, or the obs-moq/ folder (containing bin/64bit/ + data/) on Windows.

Linux is build-from-source for now (see the Linux section above). A prebuilt Linux binary isn't shipped: the plugin needs ffmpeg to decode subscribed video, and a Linux build links the nix/distro ffmpeg rather than the version OBS bundles, so it wouldn't load portably. (A future native decoder via moq-video would remove the ffmpeg dependency and let Linux ship a binary too.)

Usage

Publishing

1. Open OBS Studio
2. Go to Settings > Stream
3. Select "MoQ" as the service
4. Enter your relay URL and path
5. Click "Start Streaming"

Subscribing

1. Add a new source
2. Select "MoQ Source"
3. Enter the relay URL and broadcast path
4. The stream will appear in your scene