主播PK互动的操作流程_视频直播(LIVE)-阿里云帮助中心

阿里云视频直播提供主播PK互动功能，该功能允许两位或多位主播在直播中展开PK，增强观众的观看体验。本文为您介绍基于RTC+CDN旁路直播的方式来实现主播PK互动的操作步骤和相关示例代码，帮助用户快速接入主播PK互动场景。

方案介绍

使用ARTC SDK提供的跨房间拉流能力可以实现主播与主播之间跨房间PK的场景。从不同的房间拉取主播的实时音视频流，同时再各自直播间分别调用UpdateLiveMPUTask - 更新混流转推任务（新）接口，模式切换成混流模式，传入目标房间的ChannelID和主播UserId，便可以将两个主播的视频画面混流到一个画面中， CDN侧观众画面从单主播画面切换成主播与主播PK画面。其主播开播和PK的流程如下：

PK前

主播端A：使用ARTC SDK加入RTC 房间A，推送音视频实时流。

业务服务器：监听RTC房间A内流变化事件，当主播推流后，调用StartLiveMPUTask - 创建混流转推任务（新），启动旁路转推任务Task1，传入直播CDN推流地址，将RTC房间A内流转推到直播CDN上。

直播间A普通观众：使用阿里云播放器SDK传入直播间A的直播CDN拉流地址，拉流播放。

主播端B：使用ARTC SDK加入RTC 房间B，推送音视频实时流。

业务服务器：监听RTC房间B内流变化事件，当主播推流后，调用StartLiveMPUTask - 创建混流转推任务（新），启动旁路转推任务Task2，传入直播CDN推流地址，将RTC房间内B流转推到直播CDN上。

直播间B普通观众：使用阿里云播放器SDK传入直播间B的直播CDN拉流地址，拉流播放。

PK中

主播端A：调用ARTC SDK的跨房间拉流接口开始拉流，传入房间B和用户B。

主播端B：调用ARTC SDK的跨房间拉流接口开始拉流，传入房间A和用户A。

业务服务器：

更新Task1成混流，分别传入房间A和用户A、房间B和用户B、混流布局信息。
更新Task2成混流，分别传入房间B和用户B、房间A和用户A、混流布局信息。

PK结束

主播端A：调用跨房间拉流接口停止拉流。

主播端B：调用跨房间拉流接口停止拉流。

业务服务器：

更新task1成旁路转推，转推房间A内用户A的流。
更新task2成旁路转推，转推房间B内用户B的流。

主播PK场景，普通观众侧不需要任何额外操作，观看画面自动从单主播画面切换成混流画面。

实现步骤

步骤一主播开播

主播开播的基本流程：

1. 主播端向RTC房间推流

主播端使用ARTC SDK，向RTC房间推流。

Android

使用ARTC SDK 加入RTC房间及推流详细步骤可参考：实现步骤

// 导入ARTC相关类
import com.alivc.rtc.AliRtcEngine;
import com.alivc.rtc.AliRtcEngineEventListener;
import com.alivc.rtc.AliRtcEngineNotify;

private AliRtcEngine mAliRtcEngine = null;
if(mAliRtcEngine == null) {
    mAliRtcEngine = AliRtcEngine.getInstance(this);
}
// 设置频道模式
mAliRtcEngine.setChannelProfile(AliRtcEngine.AliRTCSdkChannelProfile.AliRTCSdkInteractiveLive);
mAliRtcEngine.setClientRole(AliRtcEngine.AliRTCSdkClientRole.AliRTCSdkInteractive);
mAliRtcEngine.setAudioProfile(AliRtcEngine.AliRtcAudioProfile.AliRtcEngineHighQualityMode, AliRtcEngine.AliRtcAudioScenario.AliRtcSceneMusicMode);

//设置视频编码参数
AliRtcEngine.AliRtcVideoEncoderConfiguration aliRtcVideoEncoderConfiguration = new AliRtcEngine.AliRtcVideoEncoderConfiguration();
aliRtcVideoEncoderConfiguration.dimensions = new AliRtcEngine.AliRtcVideoDimensions(
                720, 1280);
aliRtcVideoEncoderConfiguration.frameRate = 20;
aliRtcVideoEncoderConfiguration.bitrate = 1200;
aliRtcVideoEncoderConfiguration.keyFrameInterval = 2000;
aliRtcVideoEncoderConfiguration.orientationMode = AliRtcVideoEncoderOrientationModeAdaptive;
mAliRtcEngine.setVideoEncoderConfiguration(aliRtcVideoEncoderConfiguration);

mAliRtcEngine.publishLocalAudioStream(true);
mAliRtcEngine.publishLocalVideoStream(true);

mAliRtcEngine.setDefaultSubscribeAllRemoteAudioStreams(true);
mAliRtcEngine.subscribeAllRemoteAudioStreams(true);
mAliRtcEngine.setDefaultSubscribeAllRemoteVideoStreams(true);
mAliRtcEngine.subscribeAllRemoteVideoStreams(true);

//设置相关回调
private AliRtcEngineEventListener mRtcEngineEventListener = new AliRtcEngineEventListener() {
    @Override
    public void onJoinChannelResult(int result, String channel, String userId, int elapsed) {
        super.onJoinChannelResult(result, channel, userId, elapsed);
        handleJoinResult(result, channel, userId);
    }

    @Override
    public void onLeaveChannelResult(int result, AliRtcEngine.AliRtcStats stats){
        super.onLeaveChannelResult(result, stats);
    }

    @Override
    public void onConnectionStatusChange(AliRtcEngine.AliRtcConnectionStatus status, AliRtcEngine.AliRtcConnectionStatusChangeReason reason){
        super.onConnectionStatusChange(status, reason);

        handler.post(new Runnable() {
            @Override
            public void run() {
                if(status == AliRtcEngine.AliRtcConnectionStatus.AliRtcConnectionStatusFailed) {
                    /* TODO: 务必处理；建议业务提示客户，此时SDK内部已经尝试了各种恢复策略已经无法继续使用时才会上报 */
                    ToastHelper.showToast(VideoChatActivity.this, R.string.video_chat_connection_failed, Toast.LENGTH_SHORT);
                } else {
                    /* TODO: 可选处理；增加业务代码，一般用于数据统计、UI变化 */
                }
            }
        });
    }
    @Override
    public void OnLocalDeviceException(AliRtcEngine.AliRtcEngineLocalDeviceType deviceType, AliRtcEngine.AliRtcEngineLocalDeviceExceptionType exceptionType, String msg){
        super.OnLocalDeviceException(deviceType, exceptionType, msg);
        /* TODO: 务必处理；建议业务提示设备错误，此时SDK内部已经尝试了各种恢复策略已经无法继续使用时才会上报 */
        handler.post(new Runnable() {
            @Override
            public void run() {
                String str = "OnLocalDeviceException deviceType: " + deviceType + " exceptionType: " + exceptionType + " msg: " + msg;
                ToastHelper.showToast(VideoChatActivity.this, str, Toast.LENGTH_SHORT);
            }
        });
    }

};

private AliRtcEngineNotify mRtcEngineNotify = new AliRtcEngineNotify() {
    @Override
    public void onAuthInfoWillExpire() {
        super.onAuthInfoWillExpire();
        /* TODO: 务必处理；Token即将过期，需要业务触发重新获取当前channel，user的鉴权信息，然后设置refreshAuthInfo即可 */
    }

    @Override
    public void onRemoteUserOnLineNotify(String uid, int elapsed){
        super.onRemoteUserOnLineNotify(uid, elapsed);
    }

    //在onRemoteUserOffLineNotify回调中解除远端视频流渲染控件的设置
    @Override
    public void onRemoteUserOffLineNotify(String uid, AliRtcEngine.AliRtcUserOfflineReason reason){
        super.onRemoteUserOffLineNotify(uid, reason);
    }

    //在onRemoteTrackAvailableNotify回调中设置远端视频流渲染控件
    @Override
    public void onRemoteTrackAvailableNotify(String uid, AliRtcEngine.AliRtcAudioTrack audioTrack, AliRtcEngine.AliRtcVideoTrack videoTrack){
        handler.post(new Runnable() {
            @Override
            public void run() {
                if(videoTrack == AliRtcVideoTrackCamera) {
                    SurfaceView surfaceView = mAliRtcEngine.createRenderSurfaceView(VideoChatActivity.this);
                    surfaceView.setZOrderMediaOverlay(true);
                    FrameLayout view = getAvailableView();
                    if (view == null) {
                        return;
                    }
                    remoteViews.put(uid, view);
                    view.addView(surfaceView, new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
                    AliRtcEngine.AliRtcVideoCanvas remoteVideoCanvas = new AliRtcEngine.AliRtcVideoCanvas();
                    remoteVideoCanvas.view = surfaceView;
                    mAliRtcEngine.setRemoteViewConfig(remoteVideoCanvas, uid, AliRtcVideoTrackCamera);
                } else if(videoTrack == AliRtcVideoTrackNo) {
                    if(remoteViews.containsKey(uid)) {
                        ViewGroup view = remoteViews.get(uid);
                        if(view != null) {
                            view.removeAllViews();
                            remoteViews.remove(uid);
                            mAliRtcEngine.setRemoteViewConfig(null, uid, AliRtcVideoTrackCamera);
                        }
                    }
                }
            }
        });
    }

    /* 业务可能会触发同一个UserID的不同设备抢占的情况，所以这个地方也需要处理 */
    @Override
    public void onBye(int code){
        handler.post(new Runnable() {
            @Override
            public void run() {
                String msg = "onBye code:" + code;
            }
        });
    }
};

mAliRtcEngine.setRtcEngineEventListener(mRtcEngineEventListener);
mAliRtcEngine.setRtcEngineNotify(mRtcEngineNotify);

//本地预览
mLocalVideoCanvas = new AliRtcEngine.AliRtcVideoCanvas();
SurfaceView localSurfaceView = mAliRtcEngine.createRenderSurfaceView(VideoChatActivity.this);
localSurfaceView.setZOrderOnTop(true);
localSurfaceView.setZOrderMediaOverlay(true);
FrameLayout fl_local = findViewById(R.id.fl_local);
fl_local.addView(localSurfaceView, layoutParams);
mLocalVideoCanvas.view = localSurfaceView;
mAliRtcEngine.setLocalViewConfig(mLocalVideoCanvas, AliRtcVideoTrackCamera);
mAliRtcEngine.startPreview();

//加入RTC房间
mAliRtcEngine.joinChannel(token, null, null, null);

iOS

使用ARTC SDK 加入RTC房间及推流详细步骤可参考：实现步骤

// 导入ARTC相关类
import AliVCSDK_ARTC

private var rtcEngine: AliRtcEngine? = nil
// 创建引擎并设置回调
let engine = AliRtcEngine.sharedInstance(self, extras:nil)
...
self.rtcEngine = engine
// 设置频道模式
engine.setChannelProfile(AliRtcChannelProfile.interactivelive)
engine.setClientRole(AliRtcClientRole.roleInteractive)
engine.setAudioProfile(AliRtcAudioProfile.engineHighQualityMode, audio_scene: AliRtcAudioScenario.sceneMusicMode)

//设置视频编码参数
let config = AliRtcVideoEncoderConfiguration()
config.dimensions = CGSize(width: 720, height: 1280)
config.frameRate = 20
config.bitrate = 1200
config.keyFrameInterval = 2000
config.orientationMode = AliRtcVideoEncoderOrientationMode.adaptive
engine.setVideoEncoderConfiguration(config)
engine.setCapturePipelineScaleMode(.post)

engine.publishLocalVideoStream(true)
engine.publishLocalAudioStream(true)

engine.setDefaultSubscribeAllRemoteAudioStreams(true)
engine.subscribeAllRemoteAudioStreams(true)
engine.setDefaultSubscribeAllRemoteVideoStreams(true)
engine.subscribeAllRemoteVideoStreams(true)

//设置相关回调
extension VideoCallMainVC: AliRtcEngineDelegate {

    func onJoinChannelResult(_ result: Int32, channel: String, elapsed: Int32) {
        "onJoinChannelResult1 result: \(result)".printLog()
    }

    func onJoinChannelResult(_ result: Int32, channel: String, userId: String, elapsed: Int32) {
        "onJoinChannelResult2 result: \(result)".printLog()
    }

    func onRemoteUser(onLineNotify uid: String, elapsed: Int32) {
        // 远端用户的上线
        "onRemoteUserOlineNotify uid: \(uid)".printLog()
    }

    func onRemoteUserOffLineNotify(_ uid: String, offlineReason reason: AliRtcUserOfflineReason) {
        // 远端用户的下线
        "onRemoteUserOffLineNotify uid: \(uid) reason: \(reason)".printLog()
    }


    func onRemoteTrackAvailableNotify(_ uid: String, audioTrack: AliRtcAudioTrack, videoTrack: AliRtcVideoTrack) {
        "onRemoteTrackAvailableNotify uid: \(uid) audioTrack: \(audioTrack)  videoTrack: \(videoTrack)".printLog()
    }

    func onAuthInfoWillExpire() {
        "onAuthInfoWillExpire".printLog()

        /* TODO: 务必处理；Token即将过期，需要业务触发重新获取当前channel，user的鉴权信息，然后设置refreshAuthInfo即可 */
    }

    func onAuthInfoExpired() {
        "onAuthInfoExpired".printLog()

        /* TODO: 务必处理；提示Token失效，并执行离会与释放引擎 */
    }

    func onBye(_ code: Int32) {
        "onBye code: \(code)".printLog()

        /* TODO: 务必处理；业务可能会触发同一个UserID的不同设备抢占的情况 */
    }

    func onLocalDeviceException(_ deviceType: AliRtcLocalDeviceType, exceptionType: AliRtcLocalDeviceExceptionType, message msg: String?) {
        "onLocalDeviceException deviceType: \(deviceType)  exceptionType: \(exceptionType)".printLog()

        /* TODO: 务必处理；建议业务提示设备错误，此时SDK内部已经尝试了各种恢复策略已经无法继续使用时才会上报 */
    }

    func onConnectionStatusChange(_ status: AliRtcConnectionStatus, reason: AliRtcConnectionStatusChangeReason) {
        "onConnectionStatusChange status: \(status)  reason: \(reason)".printLog()

        if status == .failed {
            /* TODO: 务必处理；建议业务提示用户，此时SDK内部已经尝试了各种恢复策略已经无法继续使用时才会上报 */
        }
        else {
            /* TODO: 可选处理；增加业务代码，一般用于数据统计、UI变化 */
        }
    }
}


//本地预览
let videoView = self.createVideoView(uid: self.userId)
let canvas = AliVideoCanvas()
canvas.view = videoView.canvasView
canvas.renderMode = .auto
canvas.mirrorMode = .onlyFrontCameraPreviewEnabled
canvas.rotationMode = ._0
self.rtcEngine?.setLocalViewConfig(canvas, for: AliRtcVideoTrack.camera)
self.rtcEngine?.startPreview()

//加入RTC房间
let ret = self.rtcEngine?.joinChannel(joinToken, channelId: nil, userId: nil, name: nil) { [weak self] errCode, channelId, userId, elapsed in
    if errCode == 0 {
        // success

    }
    else {
        // failed
    }
    
    let resultMsg = "\(msg) \n CallbackErrorCode: \(errCode)"
    resultMsg.printLog()
    UIAlertController.showAlertWithMainThread(msg: resultMsg, vc: self!)
}

let resultMsg = "\(msg) \n ReturnErrorCode: \(ret ?? 0)"
resultMsg.printLog()
if ret != 0 {
    UIAlertController.showAlertWithMainThread(msg: resultMsg, vc: self)
}

2. 客户业务服务发起转推任务，将RTC房间流转推到CDN

客户业务Server创建订阅RTC房间消息的回调，监听房间内主播推流事件，订阅RTC房间消息的回调详细接口参考：CreateEventSub - 创建订阅房间消息回调。
当收到RTC房间内主播推流后，调用旁路转推OpenAPI接口StartLiveMPUTask，将RTC房间内的流转推到CDN上，旁路转推接口详情参考：StartLiveMPUTask - 创建混流转推任务（新）。
说明
主播开播时可以将MixMode设置成0，表示单路转推不转码。接口需要传入直播推流地址，仅支持 RTMP协议，生成规则请参见生成推流地址和播放地址。
客户业务Server监听CDN推流回调，当流转推到CDN后，下发直播拉流地址，通知普通观众端播放。CDN 推流回调详情参考：回调设置。

3. 普通观众端使用阿里云播放器SDK拉流播放

当普通观众端接收到业务服务拉流通知后，创建阿里云播放器实例，使用直播拉流地址进行播放。详细的播放器接口及使用请参考：播放器SDK。

说明

建议将普通观众的CDN播放地址由RTMP格式改为HTTP-FLV格式。两者内容一致，但传输协议不同。HTTP作为互联网主流协议，具备更成熟的网络优化基础，且默认使用80/443端口，更易通过防火墙；而RTMP协议较旧，常用端口1935可能被限制，影响播放稳定性。综合来看，HTTP-FLV在通用性和播放体验（如卡顿、延迟）上优于RTMP，推荐优先使用。

Android

AliPlayer aliPlayer = AliPlayerFactory.createAliPlayer(context);
aliPlayer.setAutoPlay(true);

UrlSource urlSource = new UrlSource();
urlSource.setUri("http://test.alivecdn.com/live/streamId.flv?auth_key=XXX");  //普通观众（非连麦观众）的CDN播放地址
aliPlayer.setDataSource(urlSource);
aliPlayer.prepare();

iOS

self.cdnPlayer = [[AliPlayer alloc] init];
self.cdnPlayer.delegate = self;
self.cdnPlayer.autoPlay = YES;

AVPUrlSource *source = [[AVPUrlSource alloc] urlWithString:@""http://test.alivecdn.com/live/streamId.flv?auth_key=XXX"];
[self.cdnPlayer setUrlSource:source];
[self.cdnPlayer prepare];

步骤二主播跨房间PK

主播A和主播B跨房间PK的基本流程：

1.主播A和主播B开始跨房间拉流

主播A和主播B分别调用跨房间拉流接口，传入目标的房间ID和用户ID，开始跨房间拉流。

Android

mAliRtcEngine.subscribeRemoteDestChannelStream(channelId, userId, AliRtcVideoTrackCamera, AliRtcAudioTrackMic, true);

iOS

[self.rtcEngine subscribeRemoteDestChannelStream:channelId uid:userId videoTrack:AliRtcVideoTrackCamera audioTrack:AliRtcAudioTrackMic sub:YES];

2.分别设置主播A和主播B渲染画面

Android

在初始化引擎的时候设置对应回调mAliRtcEngine.setRtcEngineNotify，需要在onRemoteTrackAvailableNotify回调中，为远端用户设置远端视图，示例代码如下：

@Override
public void onRemoteTrackAvailableNotify(String uid, AliRtcEngine.AliRtcAudioTrack audioTrack, AliRtcEngine.AliRtcVideoTrack videoTrack){
    handler.post(new Runnable() {
        @Override
        public void run() {
            if(videoTrack == AliRtcVideoTrackCamera) {
                SurfaceView surfaceView = mAliRtcEngine.createRenderSurfaceView(VideoChatActivity.this);
                surfaceView.setZOrderMediaOverlay(true);
                FrameLayout fl_remote = findViewById(R.id.fl_remote);
                if (fl_remote == null) {
                    return;
                }
                fl_remote.addView(surfaceView, new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
                AliRtcEngine.AliRtcVideoCanvas remoteVideoCanvas = new AliRtcEngine.AliRtcVideoCanvas();
                remoteVideoCanvas.view = surfaceView;
                mAliRtcEngine.setRemoteViewConfig(remoteVideoCanvas, uid, AliRtcVideoTrackCamera);
            } else if(videoTrack == AliRtcVideoTrackNo) {
                FrameLayout fl_remote = findViewById(R.id.fl_remote);
                fl_remote.removeAllViews();
                mAliRtcEngine.setRemoteViewConfig(null, uid, AliRtcVideoTrackCamera);
            }
        }
    });
}

iOS

远端用户并进行推流或停止推流时，会触发onRemoteTrackAvailableNotify回调，在回调会设置或移除远端视图，示例代码如下：

func onRemoteTrackAvailableNotify(_ uid: String, audioTrack: AliRtcAudioTrack, videoTrack: AliRtcVideoTrack) {
    "onRemoteTrackAvailableNotify uid: \(uid) audioTrack: \(audioTrack)  videoTrack: \(videoTrack)".printLog()
    // 远端用户的流状态
    if audioTrack != .no {
        let videoView = self.videoViewList.first { $0.uidLabel.text == uid }
        if videoView == nil {
            _ = self.createVideoView(uid: uid)
        }
    }
    if videoTrack != .no {
        var videoView = self.videoViewList.first { $0.uidLabel.text == uid }
        if videoView == nil {
            videoView = self.createVideoView(uid: uid)
        }
        
        let canvas = AliVideoCanvas()
        canvas.view = videoView!.canvasView
        canvas.renderMode = .auto
        canvas.mirrorMode = .onlyFrontCameraPreviewEnabled
        canvas.rotationMode = ._0
        self.rtcEngine?.setRemoteViewConfig(canvas, uid: uid, for: AliRtcVideoTrack.camera)
    }
    else {
        self.rtcEngine?.setRemoteViewConfig(nil, uid: uid, for: AliRtcVideoTrack.camera)
    }
    
    if audioTrack == .no && videoTrack == .no {
        self.removeVideoView(uid: uid)
        self.rtcEngine?.setRemoteViewConfig(nil, uid: uid, for: AliRtcVideoTrack.camera)
    }
}

3.业务服务更新旁路转推到混流转推

业务服务收到业务App通知过来的开始主播跨房间PK的事件后，分别调用UpdateLiveMPUTask - 更新混流转推任务（新）更新直播间A和直播间B的转推任务，在UserInfos字段传入分别传入主播A和主播B的房间号及用户ID，Layout字段传入混流布局以及其他必要字段，更新混流。

步骤三结束PK

主播A和主播B结束跨房间PK的基本流程：

1.主播A和主播B停止跨房间拉流

主播A和主播B分别调用跨房间拉流接口，传入目标的房间ID和用户ID，停止跨房间拉流。

Android

mAliRtcEngine.subscribeRemoteDestChannelStream(channelId, userId, AliRtcVideoTrackCamera, AliRtcAudioTrackMic, false);

iOS

[self.rtcEngine subscribeRemoteDestChannelStream:channelId uid:userId videoTrack:AliRtcVideoTrackCamera audioTrack:AliRtcAudioTrackMic sub:NO];

2.业务服务更新旁路转推到旁路流转推

业务服务收到业务App通知过来的结束主播跨房间PK的事件后，分别调用UpdateLiveMPUTask更新直播间A和直播间B的混流转推任务，MixMode设置成0及必要字段，将混流任务更新成旁路转推任务，其UpdateLiveMPUTask接口参数详见：UpdateLiveMPUTask - 更新混流转推任务（新）

方案介绍

实现步骤

步骤一 主播开播

1. 主播端向RTC房间推流

Android

iOS

2. 客户业务服务发起转推任务，将RTC房间流转推到CDN

3. 普通观众端使用阿里云播放器SDK拉流播放

Android

iOS

步骤二 主播跨房间PK

1.主播A和主播B开始跨房间拉流

Android

iOS

2.分别设置主播A和主播B渲染画面

Android

iOS

3.业务服务更新旁路转推到混流转推

步骤三 结束PK

1.主播A和主播B停止跨房间拉流

Android

iOS

2.业务服务更新旁路转推到旁路流转推

步骤一主播开播

步骤二主播跨房间PK

步骤三结束PK