41fbcec2cd
* Fix header size calculation in stats.
With pacer inserting some extensions, the header size used in stats
(and more impoetantly when probing for bandwidth estimation and
metering the bytes to control the probes) was incorrect. The size
was effectively was that of incoming extensions. It would have been
close enough though.
Anyhow, a bit of history
- initially was planning on packaging all the necessary fields into
pacer packet and pacer would callback after sending, but that was not
great for a couple of reasons
- had to send in a bunch of useless data (as far as pacer is
concerned) into pacer.
- callback every packet (this is not bad, just a function call which
happens in the foward path too, but had to lug around the above
data).
- in the forward path, there is a very edge case issue when calling stats update
after pacer.Enqueue() - details in https://github.com/livekit/livekit/pull/2085,
but that is a rare case.
Because of those reasons, the update was placed in the forward path
before enqueue, but did not notice the header size issue till now.
As a compromise, `pacer.Enqueue` returns the headerSize and payloadSize.
It uses a dummy header to calculate size. Real extension will be added
just before sending packet on the wire. pion/rtp replaces extension if
one is already present. So, the dummy would be replaced by the real one
before sending on the wire.
a21194ecfb/packet.go (L398)
This does introduce back the second rare edge case, but that is very
rare and even if it happens, not catastrophic.
* cleanup
* add extensions and dummy as well in downtrack to make pacer cleaner
LiveKit: Real-time video, audio and data for developers
LiveKit is an open source project that provides scalable, multi-user conferencing based on WebRTC. It's designed to provide everything you need to build real-time video audio data capabilities in your applications.
LiveKit's server is written in Go, using the awesome Pion WebRTC implementation.
Features
- Scalable, distributed WebRTC SFU (Selective Forwarding Unit)
- Modern, full-featured client SDKs
- Built for production, supports JWT authentication
- Robust networking and connectivity, UDP/TCP/TURN
- Easy to deploy: single binary, Docker or Kubernetes
- Advanced features including:
- speaker detection
- simulcast
- end-to-end optimizations
- selective subscription
- moderation APIs
- end-to-end encryption
- SVC codecs (VP9, AV1)
- webhooks
- distributed and multi-region
Documentation & Guides
Live Demos
- LiveKit Meet (source)
- Spatial Audio (source)
- Livestreaming from OBS Studio (source)
- AI voice assistant using ChatGPT (source)
Ecosystem
- Agents: build real-time multimodal AI applications with programmable backend participants
- Egress: record or multi-stream rooms and export individual tracks
- Ingress: ingest streams from external sources like RTMP, WHIP, HLS, or OBS Studio
SDKs & Tools
Client SDKs
Client SDKs enable your frontend to include interactive, multi-user experiences.
| Language | Repo | Declarative UI | Links |
|---|---|---|---|
| JavaScript (TypeScript) | client-sdk-js | React | docs | JS example | React example |
| Swift (iOS / MacOS) | client-sdk-swift | Swift UI | docs | example |
| Kotlin (Android) | client-sdk-android | Compose | docs | example | Compose example |
| Flutter (all platforms) | client-sdk-flutter | native | docs | example |
| Unity WebGL | client-sdk-unity-web | docs | |
| React Native (beta) | client-sdk-react-native | native | |
| Rust | client-sdk-rust |
Server SDKs
Server SDKs enable your backend to generate access tokens, call server APIs, and receive webhooks. In addition, the Go SDK includes client capabilities, enabling you to build automations that behave like end-users.
| Language | Repo | Docs |
|---|---|---|
| Go | server-sdk-go | docs |
| JavaScript (TypeScript) | server-sdk-js | docs |
| Ruby | server-sdk-ruby | |
| Java (Kotlin) | server-sdk-kotlin | |
| Python (community) | python-sdks | |
| PHP (community) | agence104/livekit-server-sdk-php |
Tools
- CLI - command line interface & load tester
- Docker image
- Helm charts
Install
Tip
We recommend installing LiveKit CLI along with the server. It lets you access server APIs, create tokens, and generate test traffic.
The following will install LiveKit's media server:
MacOS
brew install livekit
Linux
curl -sSL https://get.livekit.io | bash
Windows
Download the latest release here
Getting Started
Starting LiveKit
Start LiveKit in development mode by running livekit-server --dev. It'll use a placeholder API key/secret pair.
API Key: devkey
API Secret: secret
To customize your setup for production, refer to our deployment docs
Creating access token
A user connecting to a LiveKit room requires an access token. Access tokens (JWT) encode the user's identity and the room permissions they've been granted. You can generate a token with our CLI:
livekit-cli create-token \
--api-key devkey --api-secret secret \
--join --room my-first-room --identity user1 \
--valid-for 24h
Test with example app
Head over to our example app and enter a generated token to connect to your LiveKit server. This app is built with our React SDK.
Once connected, your video and audio are now being published to your new LiveKit instance!
Simulating a test publisher
livekit-cli join-room \
--url ws://localhost:7880 \
--api-key devkey --api-secret secret \
--room my-first-room --identity bot-user1 \
--publish-demo
This command publishes a looped demo video to a room. Due to how the video clip was encoded (keyframes every 3s), there's a slight delay before the browser has sufficient data to begin rendering frames. This is an artifact of the simulation.
Deployment
Use LiveKit Cloud
LiveKit Cloud is the fastest and most reliable way to run LiveKit. Every project gets free monthly bandwidth and transcoding credits.
Sign up for LiveKit Cloud.
Self-host
Read our deployment docs for more information.
Building from source
Pre-requisites:
- Go 1.22+ is installed
- GOPATH/bin is in your PATH
Then run
git clone https://github.com/livekit/livekit
cd livekit
./bootstrap.sh
mage
Contributing
We welcome your contributions toward improving LiveKit! Please join us on Slack to discuss your ideas and/or PRs.
License
LiveKit server is licensed under Apache License v2.0.
| LiveKit Ecosystem | |
|---|---|
| Realtime SDKs | React Components · Browser · Swift Components · iOS/macOS/visionOS · Android · Flutter · React Native · Rust · Node.js · Python · Unity (web) · Unity (beta) |
| Server APIs | Node.js · Golang · Ruby · Java/Kotlin · Python · Rust · PHP (community) |
| Agents Frameworks | Python · Playground |
| Services | LiveKit server · Egress · Ingress · SIP |
| Resources | Docs · Example apps · Cloud · Self-hosting · CLI |