Streaming Quick Start

Module: LCKStreaming | Version: 1.0 | Platforms: Win64, Android (Quest)

Overview

This guide walks through enabling and using LCKStreaming from C++ in five steps. By the end, your game will authenticate with the LIV backend and stream to YouTube, Twitch, or a manual RTMP endpoint.

Before you begin, ensure you have a LIV developer account, a valid Tracking ID, and an active streaming subscription. See the Streaming Overview for all prerequisites.

Pairing to LIV Hub in Play In Editor mode

You must pair your game to LIV Hub on your Meta Quest. ie: LIV Hub doesn’t need to be on the same device that you’re pairing the game to.

In editor, while in play mode, go to the streaming tab to trigger the pairing code
In LIV Hub on the Meta Quest, pair your game via the LIV Camera Games section
Enter the pairing code in the editor

Step 1: Enable Streaming

In Project Settings → Plugins → LCK SDK → Features, enable bEnableStreaming. You can also set it in your DefaultGame.ini:

[/Script/LCKCore.LCKDeveloperSettings]
bEnableStreaming=true

Step 2: Add Module Dependencies

// YourProject.Build.cs
PublicDependencyModuleNames.AddRange(new string[] {
    "LCKStreaming",
    "LCKCore"
});

Step 3: Access the Subsystem

ULCKStreamingSubsystem is a UGameInstanceSubsystem. Access it from any point where you have a valid game instance.

#include "LCKStreamingSubsystem.h"

ULCKStreamingSubsystem* Streaming =
    GetGameInstance()->GetSubsystem<ULCKStreamingSubsystem>();

Step 4: Authenticate and Stream

The minimum flow is: start login, wait for authentication, then start streaming.

void UMyStreamingManager::BeginStreaming()
{
    ULCKStreamingSubsystem* Streaming =
        GetGameInstance()->GetSubsystem<ULCKStreamingSubsystem>();

    if (!Streaming)
    {
        return;
    }

    // Bind delegates before starting login
    Streaming->OnPairingCodeReceived.AddDynamic(
        this, &UMyStreamingManager::HandlePairingCode);
    Streaming->OnAuthenticated.AddDynamic(
        this, &UMyStreamingManager::HandleAuthenticated);
    Streaming->OnStreamStarted.AddDynamic(
        this, &UMyStreamingManager::HandleStreamStarted);
    Streaming->OnStreamStopped.AddDynamic(
        this, &UMyStreamingManager::HandleStreamStopped);
    Streaming->OnStreamError.AddDynamic(
        this, &UMyStreamingManager::HandleStreamError);

    // Begin device pairing
    Streaming->StartLogin();
}

void UMyStreamingManager::HandlePairingCode(const FString& Code)
{
    // Display this code in your UI
    // User enters it at dashboard.liv.tv/pair
    UE_LOG(LogTemp, Log, TEXT("Pairing code: %s"), *Code);
}

void UMyStreamingManager::HandleAuthenticated()
{
    UE_LOG(LogTemp, Log, TEXT("Authenticated — starting stream"));

    ULCKStreamingSubsystem* Streaming =
        GetGameInstance()->GetSubsystem<ULCKStreamingSubsystem>();

    if (Streaming && Streaming->HasStreamingTarget())
    {
        Streaming->StartStreaming();
    }
}

void UMyStreamingManager::HandleStreamStarted()
{
    UE_LOG(LogTemp, Log, TEXT("Stream is live"));
}

void UMyStreamingManager::HandleStreamStopped()
{
    UE_LOG(LogTemp, Log, TEXT("Stream stopped"));
}

void UMyStreamingManager::HandleStreamError(const FString& ErrorMessage)
{
    UE_LOG(LogTemp, Error, TEXT("Stream error: %s"), *ErrorMessage);
}

Step 5: Stop Streaming

void UMyStreamingManager::EndStreaming()
{
    ULCKStreamingSubsystem* Streaming =
        GetGameInstance()->GetSubsystem<ULCKStreamingSubsystem>();

    if (Streaming && Streaming->IsStreaming())
    {
        Streaming->StopStreaming();
    }
}

Complete State Check Example

Use the state query methods to build your UI:

void UMyStreamingWidget::UpdateUI()
{
    ULCKStreamingSubsystem* Streaming =
        GetGameInstance()->GetSubsystem<ULCKStreamingSubsystem>();

    if (!Streaming)
    {
        return;
    }

    // Authentication state
    bool bLoggedIn = Streaming->IsAuthenticated();

    // Subscription check
    bool bCanStream = Streaming->HasActiveSubscription();

    // Target info
    bool bHasTarget = Streaming->HasStreamingTarget();
    FString TargetName = Streaming->GetStreamingTargetName(); // "YouTube", "Twitch", "Manual"

    // Stream state
    bool bIsLive = Streaming->IsStreaming();
    bool bIsStarting = Streaming->IsStartingOrStreaming();
}

All Available Delegates

Delegate	Signature	When
`OnPairingCodeReceived`	`FOnLCKPairingCodeReceived(const FString&, Code)`	Pairing code ready for display
`OnAuthenticated`	`FOnLCKAuthenticated()`	Login succeeded
`OnStreamingConfigReceived`	`FOnLCKStreamingConfigReceived(ELCKStreamingTargetType, const FLCKUserSubscription&)`	Config loaded from server
`OnStreamStarted`	`FOnLCKStreamStarted()`	RTMP connection active
`OnStreamStopped`	`FOnLCKStreamStopped()`	Stream ended cleanly
`OnStreamError`	`FOnLCKStreamError(const FString&, ErrorMessage)`	An error occurred
`OnLoggedOut`	`FOnLCKLoggedOut()`	User logged out

Always bind delegates before calling StartLogin() or StartStreaming() to avoid missing events that fire quickly.

Troubleshooting

StartStreaming() returns false

Check IsAuthenticated() — the user must be logged in first
Check HasStreamingTarget() — the streaming config must be loaded
Check HasActiveSubscription() — an active subscription is required
Verify bEnableStreaming is true in project settings
Check LogLCKStreaming for detailed error output

Stream starts but drops immediately

Check OnStreamError for the error message
Verify network connectivity to the RTMP ingest server
Ensure the encoder is available (not locked by another process)
The health check allows 2 consecutive failures before stopping — check logs for encoder health warnings

Pairing code never arrives

Verify network connectivity to dashboard.liv.tv
Check that the Tracking ID is valid
Look for errors in LogLCKStreaming

Streaming Overview

Architecture and platform details

Authentication

Detailed authentication and pairing guide

Recording

Record locally while streaming

Core SDK

Tablet Interface

Tablet Customization

Audio

Streaming

API Reference

Overview

Pairing to LIV Hub in Play In Editor mode

Step 1: Enable Streaming

Step 2: Add Module Dependencies

Step 3: Access the Subsystem

Step 4: Authenticate and Stream

Step 5: Stop Streaming

Complete State Check Example

All Available Delegates

Troubleshooting

See Also

Streaming Overview

Authentication

Recording

​Overview

​Pairing to LIV Hub in Play In Editor mode

​Step 1: Enable Streaming

​Step 2: Add Module Dependencies

​Step 3: Access the Subsystem

​Step 4: Authenticate and Stream

​Step 5: Stop Streaming

​Complete State Check Example

​All Available Delegates

​Troubleshooting

​See Also

Streaming Overview

Authentication

Recording

Overview

Pairing to LIV Hub in Play In Editor mode

Step 1: Enable Streaming

Step 2: Add Module Dependencies

Step 3: Access the Subsystem

Step 4: Authenticate and Stream

Step 5: Stop Streaming

Complete State Check Example

All Available Delegates

Troubleshooting

See Also