LiveKit Unity SDK

⚠️ Warning

This SDK is currently in Developer Preview mode and not ready for production use. There will be bugs and APIs may change during this period.

We welcome and appreciate any feedback or contributions. You can create issues here or chat live with us in the #rust-developer-preview channel within the LiveKit Community Slack.

Use this SDK to add real-time video, audio and data features to your Unity app. By connecting to a self- or cloud-hosted LiveKit server, you can quickly build applications like interactive live streaming or video calls with just a few lines of code.

Platform Support

• Windows
• MacOS
• Linux
• iOS
• Android
• WebGL

We plan to support all Unity platforms with this SDK. WebGL is currently supported with client-sdk-unity-web.

Installation

Follow this unity tutorial,

clone this repo and download the ffi binaries.

git clone https://github.com/livekit/client-sdk-unity.git
cd client-sdk-unity

You can use the package manager to import local client-sdk-unity into your Unity project.

Or you can import the git url https://github.com/livekit/client-sdk-unity.git from the package manager.

iOS

Add dependent frameworks to your Unity project

select Unity-iPhone -> TARGETS -> UnityFramework -> General -> Frameworks and Libraries -> +

add the following frameworks:

OpenGLES.framework MetalKit.framework GLKit.framework MetalKit.framework VideoToolBox.framework Network.framework

add other linker flags to UnityFramework:

-ObjC

Since libiPhone-lib.a has built-in old versions of celt and libvpx (This will cause the opus and vp8/vp9 codecs to not be called correctly and cause a crash.), so you need to adjust the link order to ensure that it is linked to liblivekit_ffi.a first.

The fix is ​​to remove and re-add libiPhone-lib.a from Frameworks and Libraries, making sure to link after liblivekit_ffi.a.

Examples

And you can also follow the example app in the unity-example to see how to use the SDK.

Connect to a room

using LiveKit;

IEnumerator Start()
{
    var room = new Room();
    room.TrackSubscribed += TrackSubscribed;

    var connect = room.Connect("ws://localhost:7880", "<join-token>");
    yield return connect;
    if (!connect.IsError)
    {
        Debug.Log("Connected to " + room.Name);
    }
}

Publishing microphone

// Publish Microphone
var localSid = "my-audio-source";
GameObject audObject = new GameObject(localSid);
var source = audObject.AddComponent<AudioSource>();
source.clip = Microphone.Start(Microphone.devices[0], true, 2, (int)RtcAudioSource.DefaultSampleRate);
source.loop = true;

var rtcSource = new RtcAudioSource(source);
var track = LocalAudioTrack.CreateAudioTrack("my-audio-track", rtcSource, room);

var options = new TrackPublishOptions();
options.AudioEncoding = new AudioEncoding();
options.AudioEncoding.MaxBitrate = 64000;
options.Source = TrackSource.SourceMicrophone;

var publish = room.LocalParticipant.PublishTrack(track, options);
yield return publish;

if (!publish.IsError)
{
    Debug.Log("Track published!");
}

rtcSource.Start();

Publishing a texture (e.g Unity Camera)

// publish a WebCamera
//var source = new TextureVideoSource(webCamTexture);

// Publish the entire screen
//var source = new ScreenVideoSource();

// Publishing a Unity Camera
//Camera.main.enabled = true;
//var source = new CameraVideoSource(Camera.main);

var rt = new UnityEngine.RenderTexture(1920, 1080, 24, RenderTextureFormat.ARGB32);
rt.Create();
Camera.main.targetTexture = rt;
var source = new TextureVideoSource(rt);
var track = LocalVideoTrack.CreateVideoTrack("my-video-track", source, room);

var options = new TrackPublishOptions();
options.VideoCodec = VideoCodec.Vp8;
var videoCoding = new VideoEncoding();
videoCoding.MaxBitrate = 512000;
videoCoding.MaxFramerate = frameRate;
options.VideoEncoding = videoCoding;
options.Simulcast = true;
options.Source = TrackSource.SourceCamera;

var publish = room.LocalParticipant.PublishTrack(track, options);
yield return publish;

if (!publish.IsError)
{
    Debug.Log("Track published!");
}

source.Start();
StartCoroutine(source.Update());

Receiving tracks

IEnumerator Start()
{
    var room = new Room();
    room.TrackSubscribed += TrackSubscribed;

    var connect = room.Connect("ws://localhost:7880", "<join-token>");
    yield return connect;

    // ....
}

void TrackSubscribed(IRemoteTrack track, RemoteTrackPublication publication, RemoteParticipant participant)
{
    if (track is RemoteVideoTrack videoTrack)
    {
        var rawImage = GetComponent<RawImage>();
        var stream = new VideoStream(videoTrack);
        stream.TextureReceived += (tex) =>
        {
            rawImage.texture = tex;
        };
        StartCoroutine(stream.Update());
        // The video data is displayed on the rawImage
    }
    else if (track is RemoteAudioTrack audioTrack)
    {
        GameObject audObject = new GameObject(audioTrack.Sid);
        var source = audObject.AddComponent<AudioSource>();
        var stream = new AudioStream(audioTrack, source);
        // Audio is being played on the source ..
    }
}

RPC

Perform your own predefined method calls from one participant to another.

This feature is especially powerful when used with Agents, for instance to forward LLM function calls to your client application.

The following is a brief overview but more detail is available in the documentation.

Registering an RPC method

The participant who implements the method and will receive its calls must first register support. Your method handler will be an async callback that receives an RpcInvocationData object:

// Define your method handler
async Task<string> HandleGreeting(RpcInvocationData data)
{
    Debug.Log($"Received greeting from {data.CallerIdentity}: {data.Payload}");
    return $"Hello, {data.CallerIdentity}!";
}

// Register the method after connection to the room
room.LocalParticipant.RegisterRpcMethod("greet", HandleGreeting);

In addition to the payload, RpcInvocationData also contains responseTimeout, which informs you the maximum time available to return a response. If you are unable to respond in time, the call will result in an error on the caller's side.

Performing an RPC request

The caller may initiate an RPC call using coroutines:

IEnumerator PerformRpcCoroutine()
{
    var rpcCall = room.LocalParticipant.PerformRpc(new PerformRpcParams
    {
        DestinationIdentity = "recipient-identity",
        Method = "greet",
        Payload = "Hello from RPC!"
    });
    
    yield return rpcCall;

    if (rpcCall.IsError)
    {
        Debug.Log($"RPC call failed: {rpcCall.Error}");
    }
    else
    {
        Debug.Log($"RPC response: {rpcCall.Payload}");
    }
}

// Start the coroutine from another MonoBehaviour method
StartCoroutine(PerformRpcCoroutine());

You may find it useful to adjust the ResponseTimeout parameter, which indicates the amount of time you will wait for a response. We recommend keeping this value as low as possible while still satisfying the constraints of your application.

Errors

LiveKit is a dynamic realtime environment and RPC calls can fail for various reasons.

You may throw errors of the type RpcError with a string message in an RPC method handler and they will be received on the caller's side with the message intact. Other errors will not be transmitted and will instead arrive to the caller as 1500 ("Application Error"). Other built-in errors are detailed in the docs.