Monitoring Remote Participants' Stream - Flutter

Each RTCStream reports when its media stops or starts flowing. Listen with stream.on(Events.streamStateChanged, ...). The room does not deliver this event.

The handler receives the new state as a StreamState and a timestamp in milliseconds since epoch. The states are:

• FREEZE_DETECTED: the picture has stopped moving.
• FREEZE_RESOLVED: frames have flowed again for about five seconds after a freeze.
• STUCK: no media has arrived for about five seconds.
• ACTIVE: the stream started or resumed, so media is expected again. A new stream's first ACTIVE arrives about one second after it is enabled.
• ENDED: the stream was closed. Nothing more arrives on it.

room.on(Events.streamEnabled, (RTCStream stream) {
  if (stream.kind == MediaType.VIDEO) {
    stream.on(Events.streamStateChanged, (StreamState state, int timestamp) {
      print("${stream.participantId}'s video is now ${state.name}");
    });
  }
});

Remove the handler with stream.off() when you no longer need it.

To check the quality of the video you receive from a remote participant, call getVideoStats() on that participant from a timer. Refer to the Understanding Call Quality guide for the metrics it returns.

API Reference

The API references for all the methods and events utilized in this guide are provided below.

• Events.streamStateChanged
• getVideoStats()