This example demonstrates how to publish or subscribe to an audio-only stream — no camera capture, no video renderer required. This is useful for voice calls, radio-style broadcasts, or any scenario where video bandwidth is unnecessary.

What You Will Learn

• How to disable video with setVideoEnabled(false)
• That no RTCMTLVideoView renderer is needed for audio-only sessions
• How to switch between publish and subscribe roles for audio
• That camera permission is not required when video is disabled

Prerequisites

1. Add the Red5 Pro iOS SDK (Red5WebRTCKit) to your Xcode project via Swift Package Manager.
2. Copy Config.swift into your project and fill in your server details.
3. Add NSMicrophoneUsageDescription to your Info.plist. Camera permission is not required for audio-only.

Key API Call

The single change from the minimal publish/subscribe examples is .setVideoEnabled(false):

client = Red5WebrtcClientBuilder()
    .setServerIp(Config.serverIP)
    .setPort(Config.port)
    .setAppName(Config.appName)
    .setStreamName(Config.streamName)
    .setLicenseKey(Config.licenseKey)
    .setVideoEnabled(false)   // ← disable video track
    .setAudioEnabled(true)
    .setEventListener(self)
    .build()

// No setVideoRenderer() call needed

Publishing Audio Only

Because video is disabled, no preview is needed. The license validation still fires, but you can call publish() immediately after:

func onLicenseValidated(validated: Bool, message: String) {
    if validated {
        client?.publish()   // no startPreview() needed
    }
}

Subscribing Audio Only

client?.subscribe()

func onSubscribeStarted() {
    // audio is playing through the device speaker
    // no video renderer to show
}

Compared to Video Sessions

Source Code

The full example is available in the red5pro-ios-sdk-examples repository under 03-AudioOnly/.