Android平台GB28181设备接入端如何降低资源占用和性能消耗

背景

我们在做GB28181设备接入模块的时候，考虑到好多设备性能一般，我们一般的设计思路是，先注册设备到平台侧，平台侧发calalog过来，获取设备信息，然后，设备侧和国标平台侧维持心跳，如果有位置订阅信息，按照订阅时间间隔，实时上报设备位置信息。

如果本地没有录像诉求，或者，国标平台侧不发起invite请求，Android平台GB28181设备接入端，不做视频编码，甚至可以连摄像头都不打开，等有实时录像或国标平台侧视频预览播放请求的时候，再打开摄像头，毕竟摄像头单纯的打开，设备都有性能损耗，甚至一些中低端记录仪，还没编码就开始发热。

技术实现

本文以大牛直播SDK的Android平台GB28181设备接入侧为例，先启动GB28181，启动后，直接注册到国标平台侧，整体设计架构图如下：

class ButtonGB28181AgentListener implements View.OnClickListener {
  public void onClick(View v) {
    stopAudioPlayer();
    destoryRTPReceiver();

    gb_broadcast_source_id_ = null;
    gb_broadcast_target_id_ = null;
    btnGB28181AudioBroadcast.setText("GB28181语音广播");
    btnGB28181AudioBroadcast.setEnabled(false);

    stopGB28181Stream();
    destoryRTPSender();

    if (null == gb28181_agent_ ) {
      if( !initGB28181Agent() )
        return;
    }

    if (gb28181_agent_.isRunning()) {
      gb28181_agent_.terminateAllPlays(true);// 目前测试下来,发送BYE之后,有些服务器会立即发送INVITE,是否发送BYE根据实际情况看
      gb28181_agent_.stop();
      btnGB28181Agent.setText("启动GB28181");
    }
    else {
      if ( gb28181_agent_.start() ) {
        btnGB28181Agent.setText("停止GB28181");
      }
    }
  }
}

其中，initGB28181Agent()做的工作如下：

private boolean initGB28181Agent() {
  if ( gb28181_agent_ != null )
    return  true;

  getLocation(context_);

  String local_ip_addr = IPAddrUtils.getIpAddress(context_);
  Log.i(TAG, "[daniusdk]initGB28181Agent local ip addr: " + local_ip_addr);

  if ( local_ip_addr == null || local_ip_addr.isEmpty() ) {
    Log.e(TAG, "[daniusdk]initGB28181Agent local ip is empty");
    return  false;
  }

  gb28181_agent_ = GBSIPAgentFactory.getInstance().create();
  if ( gb28181_agent_ == null ) {
    Log.e(TAG, "[daniusdk]initGB28181Agent create agent failed");
    return false;
  }

  gb28181_agent_.addListener(this);
  gb28181_agent_.addPlayListener(this);
  gb28181_agent_.addAudioBroadcastListener(this);
  gb28181_agent_.addDeviceControlListener(this);
  gb28181_agent_.addQueryCommandListener(this);

  // 必填信息
  gb28181_agent_.setLocalAddress(local_ip_addr);
  gb28181_agent_.setServerParameter(gb28181_sip_server_addr_, gb28181_sip_server_port_, gb28181_sip_server_id_, gb28181_sip_domain_);
  gb28181_agent_.setUserInfo(gb28181_sip_username_, gb28181_sip_password_);
  //gb28181_agent_.setUserInfo(gb28181_sip_username_, gb28181_sip_username_, gb28181_sip_password_);

  // 可选参数
  gb28181_agent_.setUserAgent(gb28181_sip_user_agent_filed_);
  gb28181_agent_.setTransportProtocol(gb28181_sip_trans_protocol_==0?"UDP":"TCP");

  // GB28181配置
  gb28181_agent_.config(gb28181_reg_expired_, gb28181_heartbeat_interval_, gb28181_heartbeat_count_);

  com.gb.ntsignalling.Device gb_device = new com.gb.ntsignalling.Device("34020000001380000001", "安卓测试设备", Build.MANUFACTURER, Build.MODEL,
                                                                        "宇宙","火星1","火星", true);

  if (mLongitude != null && mLatitude != null) {
    com.gb.ntsignalling.DevicePosition device_pos = new com.gb.ntsignalling.DevicePosition();

    device_pos.setTime(mLocationTime);
    device_pos.setLongitude(mLongitude);
    device_pos.setLatitude(mLatitude);
    gb_device.setPosition(device_pos);

    gb_device.setSupportMobilePosition(true); // 设置支持移动位置上报
  }

  gb28181_agent_.addDevice(gb_device);

  if (!gb28181_agent_.createSipStack()) {
    gb28181_agent_ = null;
    Log.e(TAG, "[daniusdk]initGB28181Agent gb28181_agent_.createSipStack failed.");
    return  false;
  }

  boolean is_bind_local_port_ok = false;

  // 最多尝试5000个端口
  int try_end_port = gb28181_sip_local_port_base_ + 5000;
  try_end_port = try_end_port > 65536 ?65536: try_end_port;

  for (int i = gb28181_sip_local_port_base_; i < try_end_port; ++i) {
    if (gb28181_agent_.bindLocalPort(i)) {
      is_bind_local_port_ok = true;
      break;
    }
  }

  if (!is_bind_local_port_ok) {
    gb28181_agent_.releaseSipStack();
    gb28181_agent_ = null;
    Log.e(TAG, "[daniusdk]initGB28181Agent gb28181_agent_.bindLocalPort failed.");
    return  false;
  }

  if (!gb28181_agent_.initialize()) {
    gb28181_agent_.unBindLocalPort();
    gb28181_agent_.releaseSipStack();
    gb28181_agent_ = null;
    Log.e(TAG, "[daniusdk]initGB28181Agent gb28181_agent_.initialize failed.");
    return  false;
  }

  return true;
}

注册成功后，会把国标平台侧返回200 OK时带的时间返回上来，便于Android平台GB28181设备侧做校时，如有注册异常，也会返回：

@Override
public void ntsRegisterOK(String dateString) {
  Log.i(TAG, "ntsRegisterOK Date: " + (dateString!= null? dateString : ""));
}

@Override
public void ntsRegisterTimeout() {
  Log.e(TAG, "ntsRegisterTimeout");
}

@Override
public void ntsRegisterTransportError(String errorInfo) {
  Log.e(TAG, "ntsRegisterTransportError error:" + (errorInfo != null?errorInfo :""));
}

周期性的心跳，如有异常，我们也回调到上层：

@Override
public void ntsOnHeartBeatException(int exceptionCount,  String lastExceptionInfo) {
  Log.e(TAG, "ntsOnHeartBeatException heart beat timeout count reached, count:" + exceptionCount+
        ", exception info:" + (lastExceptionInfo!=null?lastExceptionInfo:""));

  // 停止信令, 然后重启
  handler_.postDelayed(new Runnable() {
    @Override
    public void run() {
      Log.i(TAG, "gb28281_heart_beart_timeout");

      stopAudioPlayer();
      destoryRTPReceiver();

      if (gb_broadcast_source_id_ != null && gb_broadcast_target_id_ != null && gb28181_agent_ != null)
        gb28181_agent_.byeAudioBroadcast(gb_broadcast_source_id_, gb_broadcast_target_id_);

      gb_broadcast_source_id_ = null;
      gb_broadcast_target_id_ = null;
      btnGB28181AudioBroadcast.setText("GB28181语音广播");
      btnGB28181AudioBroadcast.setEnabled(false);

      stopGB28181Stream();
      destoryRTPSender();

      if (gb28181_agent_ != null) {
        gb28181_agent_.terminateAllPlays(true);

        Log.i(TAG, "gb28281_heart_beart_timeout sip stop");
        gb28181_agent_.stop();

        String local_ip_addr = IPAddrUtils.getIpAddress(context_);
        if (local_ip_addr != null && !local_ip_addr.isEmpty() ) {
          Log.i(TAG, "gb28281_heart_beart_timeout get local ip addr: " + local_ip_addr);
          gb28181_agent_.setLocalAddress(local_ip_addr);
        }

        Log.i(TAG, "gb28281_heart_beart_timeout sip start");
        gb28181_agent_.start();
      }
    }

  },0);
}

如果国标平台侧订阅了实时位置信息，我们的处理如下：

@Override
public void ntsOnDevicePositionRequest(String deviceId, int interval) {
  handler_.postDelayed(new Runnable() {
    @Override
    public void run() {
      getLocation(context_);

      if (mLongitude != null && mLatitude != null) {
        com.gb.ntsignalling.DevicePosition device_pos = new com.gb.ntsignalling.DevicePosition();

        device_pos.setTime(mLocationTime);
        device_pos.setLongitude(mLongitude);
        device_pos.setLatitude(mLatitude);

        if (gb28181_agent_ != null ) {
          gb28181_agent_.updateDevicePosition(device_id_, device_pos);
        }
      }
    }

    private String device_id_;
    private int interval_;

    public Runnable set(String device_id, int interval) {
      this.device_id_ = device_id;
      this.interval_ = interval;
      return this;
    }

  }.set(deviceId, interval),0);
}

如果平台侧发起预览请求，我们的处理如下：

@Override
public void ntsOnInvitePlay(String deviceId, SessionDescription session_des) {
  handler_.postDelayed(new Runnable() {
    @Override
    public void run() {
      // 先振铃响应下
      gb28181_agent_.respondPlayInvite(180, device_id_);

      MediaSessionDescription video_des = null;
      SDPRtpMapAttribute ps_rtpmap_attr = null;

      // 28181 视频使用PS打包
      Vector video_des_list = session_des_.getVideoPSDescriptions();
      if (video_des_list != null && !video_des_list.isEmpty()) {
        for(MediaSessionDescription m : video_des_list) {
          if (m != null && m.isValidAddressType() && m.isHasAddress() ) {
            video_des = m;
            ps_rtpmap_attr = video_des.getPSRtpMapAttribute();
            break;
          }
        }
      }

      if (null == video_des) {
        gb28181_agent_.respondPlayInvite(488, device_id_);
        Log.i(TAG, "ntsOnInvitePlay get video description is null, response 488, device_id:" + device_id_);
        return;
      }

      if (null == ps_rtpmap_attr) {
        gb28181_agent_.respondPlayInvite(488, device_id_);
        Log.i(TAG, "ntsOnInvitePlay get ps rtp map attribute is null, response 488, device_id:" + device_id_);
        return;
      }

      long rtp_sender_handle = libPublisher.CreateRTPSender(0);
      if ( rtp_sender_handle == 0 ) {
        gb28181_agent_.respondPlayInvite(488, device_id_);
        Log.i(TAG, "ntsOnInvitePlay CreateRTPSender failed, response 488, device_id:" + device_id_);
        return;
      }

      gb28181_rtp_payload_type_  = ps_rtpmap_attr.getPayloadType();
      gb28181_rtp_encoding_name_ =  ps_rtpmap_attr.getEncodingName();

      libPublisher.SetRTPSenderTransportProtocol(rtp_sender_handle, video_des.isRTPOverUDP()?0:1);
      libPublisher.SetRTPSenderIPAddressType(rtp_sender_handle, video_des.isIPv4()?0:1);
      libPublisher.SetRTPSenderLocalPort(rtp_sender_handle, 0);
      libPublisher.SetRTPSenderSSRC(rtp_sender_handle, video_des.getSSRC());
      libPublisher.SetRTPSenderSocketSendBuffer(rtp_sender_handle, 2*1024*1024); // 设置到2M
      libPublisher.SetRTPSenderClockRate(rtp_sender_handle, ps_rtpmap_attr.getClockRate());
      libPublisher.SetRTPSenderDestination(rtp_sender_handle, video_des.getAddress(), video_des.getPort());

      if ( libPublisher.InitRTPSender(rtp_sender_handle) != 0 ) {
        gb28181_agent_.respondPlayInvite(488, device_id_);
        libPublisher.DestoryRTPSender(rtp_sender_handle);
        return;
      }

      int local_port = libPublisher.GetRTPSenderLocalPort(rtp_sender_handle);
      if (local_port == 0) {
        gb28181_agent_.respondPlayInvite(488, device_id_);
        libPublisher.DestoryRTPSender(rtp_sender_handle);
        return;
      }

      Log.i(TAG,"get local_port:" + local_port);

      String local_ip_addr = IPAddrUtils.getIpAddress(context_);

      MediaSessionDescription local_video_des = new MediaSessionDescription(video_des.getType());

      local_video_des.addFormat(String.valueOf(ps_rtpmap_attr.getPayloadType()));
      local_video_des.addRtpMapAttribute(ps_rtpmap_attr);

      local_video_des.setAddressType(video_des.getAddressType());
      local_video_des.setAddress(local_ip_addr);
      local_video_des.setPort(local_port);

      local_video_des.setTransportProtocol(video_des.getTransportProtocol());
      local_video_des.setSSRC(video_des.getSSRC());

      if (!gb28181_agent_.respondPlayInviteOK(device_id_,local_video_des) ) {
        libPublisher.DestoryRTPSender(rtp_sender_handle);
        Log.e(TAG, "ntsOnInvitePlay call respondPlayInviteOK failed.");
        return;
      }

      gb28181_rtp_sender_handle_ = rtp_sender_handle;
    }

    private String device_id_;
    private SessionDescription session_des_;

    public Runnable set(String device_id, SessionDescription session_des) {
      this.device_id_ = device_id;
      this.session_des_ = session_des;
      return this;
    }
  }.set(deviceId, session_des),0);
}

收到Ack后，才开始真正发送数据：

@Override
public void ntsOnAckPlay(String deviceId) {
  handler_.postDelayed(new Runnable() {
    @Override
    public void run() {
      Log.i(TAG,"ntsOnACKPlay, device_id:" +device_id_);

      if (!isRTSPPublisherRunning && !isPushingRtmp && !isRecording) {
        InitAndSetConfig();
      }

      libPublisher.SetGB28181RTPSender(publisherHandle, gb28181_rtp_sender_handle_, gb28181_rtp_payload_type_, gb28181_rtp_encoding_name_);

      //libPublisher.SetGBTCPConnectTimeout(publisherHandle, 10*60*1000);
      //libPublisher.SetGBInitialTCPReconnectInterval(publisherHandle, 1000);
      //libPublisher.SetGBInitialTCPMaxReconnectAttempts(publisherHandle, 3);

      int startRet = libPublisher.StartGB28181MediaStream(publisherHandle);
      if (startRet != 0) {

        if (!isRTSPPublisherRunning && !isPushingRtmp  && !isRecording) {
          if (publisherHandle != 0) {
            long handle = publisherHandle;
            publisherHandle = 0;
            libPublisher.SmartPublisherClose(handle);
          }
        }

        destoryRTPSender();

        Log.e(TAG, "Failed to start GB28181 service..");
        return;
      }

      if (!isRTSPPublisherRunning && !isPushingRtmp && !isRecording) {
        CheckInitAudioRecorder();
      }

      startLayerPostThread();
      isGB28181StreamRunning = true;
    }

    private String device_id_;

    public Runnable set(String device_id) {
      this.device_id_ = device_id;
      return this;
    }

  }.set(deviceId),0);
}

总结

除此之外，还有语音广播和语音对讲，这里不再赘述，GB28181规范普及之前，要想从外网远程访问局域网内的监控设备非常麻烦，一般要么RTSP转RTMP推到RTMP服务器，此外还要单独构建信令。GB28181规范，让远程、跨网访问监控设备更方便，把GB28181平台部署到外网后，前端设备只要注册到国标服务器，就可以被远程访问、管理和调取视频。但由于设备侧性能并不是非常好，如果要有好的稳定性和性能要求，需尽可能的减少性能消耗，按需打开摄像头、按需编码等。