媒体播放器

本文介绍如何调用媒体播放器相关的 API 播放本地或在线媒体资源，或将媒体资源分享给声网频道内的远端用户。

前提条件

在进行操作之前，请确保你已经在项目中实现了基本的实时音视频功能。有关详细信息，请参考实现音视频互动。

实现方法

参考如下步骤，在你的项目中使用媒体播放器：

1. 初始化 IRtcEngine 后，创建一个 IMediaPlayer 对象。

   C++

   void CAgoraMediaPlayer::InitMediaPlayerKit() {
       // 创建声网媒体播放器
       m_mediaPlayer = m_rtcEngine->createMediaPlayer().get();
       m_lstInfo.InsertString(m_lstInfo.GetCount(), _T("createAgoraMediaPlayer"));
       m_lstInfo.InsertString(m_lstInfo.GetCount(), _T("mediaplayer initialize"));
       // 设置播放器渲染视图
       RECT rc = {0};
       m_localVideoWnd.GetWindowRect(&rc);
       int ret = m_mediaPlayer->setView(
           (agora::media::base::view_t)m_localVideoWnd.GetSafeHwnd());
       // 设置接收播放器事件的窗口
       m_mediaPlayerEvent.SetMsgReceiver(m_hWnd);
   }

2. 调用 registerPlayerSourceObserver 方法注册播放观测器。

   C++

   void CAgoraMediaPlayer::OnBnClickedButtonJoinchannel() {
   
       // ...
       // 注册播放观测器
       ret = m_mediaPlayer->registerPlayerSourceObserver(&m_mediaPlayerEvent);
       m_lstInfo.InsertString(m_lstInfo.GetCount(),
                           _T("registerPlayerSourceObserver"));
       if (0 ==
           m_rtcEngine->joinChannel(APP_TOKEN, szChannelId.c_str(), 0, options)) {
           strInfo.Format(_T("join channel %s, use ChannelMediaOptions"),
                       getCurrentTime());
       }
   }
   else {
       // 取消注册播放观测器
       ret = m_mediaPlayer->unregisterPlayerSourceObserver(&m_mediaPlayerEvent);
       m_lstInfo.InsertString(m_lstInfo.GetCount(),
                           _T("registerPlayerSourceObserver"));
       // leave channel in the engine.
       if (0 == m_rtcEngine->leaveChannel()) {
           strInfo.Format(_T("leave channel %s"), getCurrentTime());
       }
   }
   m_lstInfo.InsertString(m_lstInfo.GetCount(), strInfo);

3. 实现媒体播放器观测器的回调。

   C++

   // 报告播放器状态改变
   LRESULT CAgoraMediaPlayer::OnmediaPlayerStateChanged(WPARAM wParam,
                                                       LPARAM lParam) {
       CString strState;
       CString strError;
       switch ((agora::media::base::MEDIA_PLAYER_STATE)wParam) {
           case agora::media::base::PLAYER_STATE_OPEN_COMPLETED:
               strState = _T("PLAYER_STATE_OPEN_COMPLETED");
               m_mediaPlayerState = mediaPLAYER_OPEN;
               int64_t duration;
               m_mediaPlayer->getDuration(duration);
               m_sldVideo.SetRangeMax((int)duration);
   
               break;
               // ...
       }
   
       switch ((agora::media::base::MEDIA_PLAYER_ERROR)lParam) {
           case agora::media::base::PLAYER_ERROR_URL_NOT_FOUND:
               strError = _T("PLAYER_ERROR_URL_NOT_FOUND");
               break;
               // ...
       }
       CString strInfo;
       strInfo.Format(_T("sta:%s,\nerr:%s"), strState, strError);
       m_lstInfo.InsertString(m_lstInfo.GetCount(), strInfo);
       return TRUE;
   }
   
   // 报告当前播放进度
   LRESULT CAgoraMediaPlayer::OnmediaPlayerPositionChanged(WPARAM wParam,
                                                           LPARAM lParam) {
       int64_t *p = (int64_t *)wParam;
       m_sldVideo.SetPos((int)*p);
       delete p;
       return TRUE;
   }

4. 调用 joinChannel 加入频道时，通过 options 参数设置媒体播放器 ID，发布媒体播放器的音视频，将媒体资源分享给声网频道内的远端用户。

   C++

   void CAgoraMediaPlayer::OnBnClickedButtonPublishVideo() {
       if (m_publishMeidaplayer) {
           ChannelMediaOptions op;
           op.clientRoleType = CLIENT_ROLE_BROADCASTER;
           op.publishMediaPlayerVideoTrack = false;
           op.publishMediaPlayerAudioTrack = false;
           op.publishMediaPlayerId = m_mediaPlayer->getMediaPlayerId();
           int ret = m_rtcEngine->updateChannelMediaOptions(op);
           ChannelMediaOptions op2;
           op2.clientRoleType = CLIENT_ROLE_BROADCASTER;
           op2.publishCameraTrack = true;
           ret = m_rtcEngine->updateChannelMediaOptions(op2);
           m_publishMeidaplayer = false;
       } else {
           ChannelMediaOptions options;
           options.clientRoleType = CLIENT_ROLE_BROADCASTER;
           options.publishMediaPlayerVideoTrack = true;
           options.publishMediaPlayerAudioTrack = true;
           options.publishMediaPlayerId = m_mediaPlayer->getMediaPlayerId();
           options.publishCameraTrack = false;
           options.publishAudioTrack = false;
           options.autoSubscribeAudio = false;
           options.autoSubscribeVideo = false;
           m_rtcEngine->updateChannelMediaOptions(options);
           m_publishMeidaplayer = true;
       }
   }

5. 调用 open 打开本地或在线媒体文件。

   C++

   void CAgoraMediaPlayer::OnBnClickedButtonOpen() {
       CString strUrl;
       CString strInfo;
       m_edtVideoSource.GetWindowText(strUrl);
       std::string tmp = cs2utf8(strUrl);
       switch (m_mediaPlayerState) {
           case mediaPLAYER_READY:
           case mediaPLAYER_STOP:
   
               if (tmp.empty()) {
                   AfxMessageBox(_T("you can fill video source."));
                   return;
               }
               // 打开媒体文件
               m_mediaPlayer->open(tmp.c_str(), 0);
               break;
           default:
               m_lstInfo.InsertString(m_lstInfo.GetCount(),
                                   _T("can not open player."));
               break;
       }
   }

6. 调用 play 播放媒体文件。如果你需要暂停播放文件，可调用 pause 方法。

   注意

   请在收到 onPlayerSourceStateChanged 回调报告播放状态为 PLAYER_STATE_OPEN_COMPLETED 后再调用 play 方法播放媒体文件。

   C++

   void CAgoraMediaPlayer::OnBnClickedButtonPlay() {
       int ret;
       switch (m_mediaPlayerState) {
           case mediaPLAYER_PAUSE:
           case mediaPLAYER_OPEN:
               // 播放媒体文件
               ret = m_mediaPlayer->play();
               if (ret == 0) {
                   m_mediaPlayerState = mediaPLAYER_PLAYING;
               }
               break;
           case mediaPLAYER_PLAYING:
               // 暂停播放
               ret = m_mediaPlayer->pause();
               if (ret == 0) {
                   m_mediaPlayerState = mediaPLAYER_PAUSE;
               }
               break;
           default:
               break;
       }
   }

7. 当用户离开频道时，停止播放、销毁媒体播放器、取消注册播放观测器，并销毁分配的资源。

   C++

   void CAgoraMediaPlayer::OnBnClickedButtonStop() {
       if (m_mediaPlayerState == mediaPLAYER_OPEN ||
           m_mediaPlayerState == mediaPLAYER_PLAYING ||
           m_mediaPlayerState == mediaPLAYER_PAUSE) {
           // 停止播放
           m_mediaPlayer->stop();
           m_mediaPlayerState = mediaPLAYER_STOP;
       }
   }
   
   void CAgoraMediaPlayer::OnDestroy() {
       // 销毁媒体播放器
       CDialogEx::OnDestroy();
       UnInitMediaPlayerKit();
   }

参考信息

示例项目

声网提供了开源的示例项目供你参考，你可以前往下载或查看其中的源代码。

MediaPlayer

支持的格式

声网的媒体播放器支持下列格式及协议：

视频编码格式

• H.263、H.264、H.265、MPEG4、MPEG2、RMVB、Theora、VP3、VP8、AVS、WMV

音频编码格式

• WAV、MP2、MP3、AAC、OPUS、FLAC、Vorbis、AMR-NB、AMR-WB、WMA v1、WMA v2

容器格式

• WAV、FLAC、OGG、MOV、ASF、FLV、PM3、MP4、MPEG-TS、Matroska (MKV)、AVI、ASS、CONCAT、DTS、AVS

支持的协议

• HTTP、HTTPS、RTMP、HLS、RTP、RTSP

API 参考

• createMediaPlayer
• destroyMediaPlayer
• registerPlayerSourceObserver
• unregisterPlayerSourceObserver
• getMediaPlayerId
• open
• play
• pause
• stop
• onPlayerSourceStateChanged
• onPositionChanged