### Start Publishing Audio Stream

Source: https://context7.com/zegolibrary/express-audio-ios/llms.txt

Publish a local audio stream to the room. Configure audio settings like bitrate, channel, and codec. Enable echo cancellation, noise suppression, and automatic gain control for better audio quality. Each stream is identified by a unique streamID.

```swift
func startPublishing(streamID: String) {
    // Configure audio settings before publishing
    let audioConfig = ZegoAudioConfig()
    audioConfig.bitrate = 48                    // Audio bitrate in kbps
    audioConfig.channel = .mono                 // Mono or stereo
    audioConfig.codecID = .default              // Audio codec
    ZegoExpressEngine.shared().setAudioConfig(audioConfig)

    // Enable echo cancellation and noise suppression
    ZegoExpressEngine.shared().enableAEC(true)
    ZegoExpressEngine.shared().enableANS(true)
    ZegoExpressEngine.shared().enableAGC(true)

    // Start publishing the audio stream
    ZegoExpressEngine.shared().startPublishingStream(streamID)

    print("Started publishing stream: \(streamID)")
}

func stopPublishing() {
    ZegoExpressEngine.shared().stopPublishingStream()
    print("Stopped publishing stream")
}
```

--------------------------------

### Initialize ZegoExpressEngine

Source: https://context7.com/zegolibrary/express-audio-ios/llms.txt

Initialize the ZegoExpressEngine singleton instance with your application ID and sign. This step is mandatory before using any other SDK features. Ensure you replace placeholder credentials with your actual ZEGO Admin Console values.

```swift
import ZegoExpressEngine

class AudioManager {

    func initializeEngine() {
        // Get your appID and appSign from ZEGO Admin Console
        let appID: UInt32 = 123456789
        let appSign = "your_app_sign_here"

        // Create engine profile
        let profile = ZegoEngineProfile()
        profile.appID = appID
        profile.appSign = appSign
        profile.scenario = .broadcast  // Use .communication for voice calls

        // Initialize the engine
        ZegoExpressEngine.createEngine(with: profile, eventHandler: self)

        print("ZegoExpressEngine initialized successfully")
    }
}

extension AudioManager: ZegoEventHandler {
    func onRoomStateChanged(_ state: ZegoRoomState, errorCode: Int32, extendedData: [AnyHashable : Any], roomID: String) {
        print("Room state changed: \(state), errorCode: \(errorCode)")
    }
}
```

--------------------------------

### Integrate Zego Express Audio in iOS

Source: https://context7.com/zegolibrary/express-audio-ios/llms.txt

A complete implementation of a view controller managing engine initialization, room login, and audio stream lifecycle.

```swift
import UIKit
import ZegoExpressEngine

class VoiceChatViewController: UIViewController {

    private let appID: UInt32 = 123456789
    private let appSign = "your_app_sign_here"
    private let roomID = "voice_room_001"
    private let userID = "user_123"
    private let streamID = "stream_user_123"

    override func viewDidLoad() {
        super.viewDidLoad()
        initializeZego()
    }

    private func initializeZego() {
        let profile = ZegoEngineProfile()
        profile.appID = appID
        profile.appSign = appSign
        profile.scenario = .communication

        ZegoExpressEngine.createEngine(with: profile, eventHandler: self)

        joinRoom()
    }

    private func joinRoom() {
        let user = ZegoUser(userID: userID, userName: "User 123")
        let config = ZegoRoomConfig()
        config.isUserStatusNotify = true

        ZegoExpressEngine.shared().loginRoom(roomID, user: user, config: config) { [weak self] errorCode, _ in
            guard errorCode == 0 else {
                print("Join room failed: \(errorCode)")
                return
            }
            self?.startPublishing()
        }
    }

    private func startPublishing() {
        ZegoExpressEngine.shared().enableAEC(true)
        ZegoExpressEngine.shared().enableANS(true)
        ZegoExpressEngine.shared().startPublishingStream(streamID)
    }

    deinit {
        ZegoExpressEngine.shared().stopPublishingStream()
        ZegoExpressEngine.shared().logoutRoom(roomID)
        ZegoExpressEngine.destroy(nil)
    }
}

extension VoiceChatViewController: ZegoEventHandler {
    func onRoomStateChanged(_ state: ZegoRoomState, errorCode: Int32, extendedData: [AnyHashable : Any], roomID: String) {
        switch state {
        case .connected:
            print("Connected to room")
        case .connecting:
            print("Connecting to room...")
        case .disconnected:
            print("Disconnected from room")
        @unknown default:
            break
        }
    }

    func onRoomStreamUpdate(_ updateType: ZegoUpdateType, streamList: [ZegoStream], extendedData: [AnyHashable : Any]?, roomID: String) {
        for stream in streamList {
            if updateType == .add {
                ZegoExpressEngine.shared().startPlayingStream(stream.streamID)
            } else {
                ZegoExpressEngine.shared().stopPlayingStream(stream.streamID)
            }
        }
    }

    func onPublisherStateUpdate(_ state: ZegoPublisherState, errorCode: Int32, extendedData: [AnyHashable : Any]?, streamID: String) {
        print("Publisher state: \(state), error: \(errorCode)")
    }

    func onPlayerStateUpdate(_ state: ZegoPlayerState, errorCode: Int32, extendedData: [AnyHashable : Any]?, streamID: String) {
        print("Player state: \(state), error: \(errorCode)")
    }
}
```

--------------------------------

### Add Swift Package Dependency

Source: https://context7.com/zegolibrary/express-audio-ios/llms.txt

Add the Zego Express Audio SDK to your project using Swift Package Manager. Specify the repository URL and version in your Package.swift file or through Xcode's package management interface.

```swift
// In your Package.swift dependencies:
dependencies: [
    .package(url: "https://github.com/zegolibrary/express-audio-ios.git", from: "3.23.1")
]

// Or add via Xcode:
// File > Add Packages > Enter repository URL:
// https://github.com/zegolibrary/express-audio-ios.git
```

--------------------------------

### Login to a Room

Source: https://context7.com/zegolibrary/express-audio-ios/llms.txt

Join a room to enable communication between users. Configure room settings such as user status notifications and maximum member count. The room acts as a channel for audio streams.

```swift
func loginRoom(roomID: String, userID: String, userName: String) {
    // Create user object
    let user = ZegoUser(userID: userID, userName: userName)

    // Configure room settings
    let roomConfig = ZegoRoomConfig()
    roomConfig.isUserStatusNotify = true  // Receive notifications when users join/leave
    roomConfig.maxMemberCount = 0         // 0 means unlimited

    // Login to the room
    ZegoExpressEngine.shared().loginRoom(roomID, user: user, config: roomConfig) { errorCode, extendedData in
        if errorCode == 0 {
            print("Successfully joined room: \(roomID)")
        } else {
            print("Failed to join room, error code: \(errorCode)")
        }
    }
}
```

--------------------------------

### Play and Stop Remote Audio Streams

Source: https://context7.com/zegolibrary/express-audio-ios/llms.txt

Functions to initiate and terminate remote stream playback, including a delegate-style handler for room stream updates.

```swift
func startPlaying(streamID: String) {
    // Start playing the remote audio stream
    ZegoExpressEngine.shared().startPlayingStream(streamID)

    print("Started playing stream: \(streamID)")
}

func stopPlaying(streamID: String) {
    ZegoExpressEngine.shared().stopPlayingStream(streamID)
    print("Stopped playing stream: \(streamID)")
}

// Handle stream updates in the room
extension AudioManager {
    func onRoomStreamUpdate(_ updateType: ZegoUpdateType, streamList: [ZegoStream], extendedData: [AnyHashable : Any]?, roomID: String) {
        for stream in streamList {
            if updateType == .add {
                // New stream available, start playing
                startPlaying(streamID: stream.streamID)
            } else {
                // Stream removed, stop playing
                stopPlaying(streamID: stream.streamID)
            }
        }
    }
}
```

--------------------------------

### Logout Room and Destroy Engine

Source: https://context7.com/zegolibrary/express-audio-ios/llms.txt

Procedures for exiting a room and releasing engine resources to prevent memory leaks.

```swift
func logoutRoom(roomID: String) {
    ZegoExpressEngine.shared().logoutRoom(roomID) { errorCode, extendedData in
        if errorCode == 0 {
            print("Successfully left room: \(roomID)")
        } else {
            print("Failed to leave room, error code: \(errorCode)")
        }
    }
}

func destroyEngine() {
    ZegoExpressEngine.destroy {
        print("ZegoExpressEngine destroyed successfully")
    }
}
```

--------------------------------

### Control Local and Remote Audio Muting

Source: https://context7.com/zegolibrary/express-audio-ios/llms.txt

Methods to toggle microphone input, publishing status, remote stream playback, and audio routing.

```swift
func muteLocalMicrophone(_ mute: Bool) {
    // Mute/unmute the local microphone (still sends silent audio)
    ZegoExpressEngine.shared().muteMicrophone(mute)
    print("Microphone muted: \(mute)")
}

func muteLocalPublishing(_ mute: Bool) {
    // Mute/unmute publishing (stops sending audio data entirely)
    ZegoExpressEngine.shared().mutePublishStreamAudio(mute)
    print("Publishing muted: \(mute)")
}

func muteRemoteStream(_ streamID: String, mute: Bool) {
    // Mute/unmute a specific remote stream
    ZegoExpressEngine.shared().mutePlayStreamAudio(streamID, mute: mute)
    print("Stream \(streamID) muted: \(mute)")
}

func setSpeakerOutput(_ useSpeaker: Bool) {
    // Route audio to speaker or earpiece
    ZegoExpressEngine.shared().setAudioRouteToSpeaker(useSpeaker)
    print("Audio route to speaker: \(useSpeaker)")
}
```

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