Class: RemoteVideoTrack

Extends

• VideoTrack

Methods

---

addProcessor(processor)

Add a VideoProcessor to allow for custom processing of video frames belonging to a VideoTrack. When a Participant un-publishes and re-publishes a VideoTrack, a new RemoteVideoTrack is created and any VideoProcessors attached to the previous RemoteVideoTrack would have to be re-added again. Only Chrome supports this as of now. Calling this API from a non-supported browser will result in a log warning.

Parameters:

Name	Type	Description
processor	VideoProcessor	The VideoProcessor to use.

Overrides:

• VideoTrack#addProcessor

Returns:

Type

this

Example

class GrayScaleProcessor {
  constructor(percentage) {
    this.percentage = percentage;
  }
  processFrame(inputFrameBuffer, outputFrameBuffer) {
    const context = outputFrameBuffer.getContext('2d');
    context.filter = `grayscale(${this.percentage}%)`;
    context.drawImage(inputFrameBuffer, 0, 0, inputFrameBuffer.width, inputFrameBuffer.height);
  }
}

const grayscaleProcessor = new GrayScaleProcessor(100);

Array.from(room.participants.values()).forEach(participant => {
  const remoteVideoTrack = Array.from(participant.videoTracks.values())[0].track;
  remoteVideoTrack.addProcessor(grayscaleProcessor);
});

---

attach()

Create an HTMLVideoElement and attach the VideoTrack to it.

The HTMLVideoElement's srcObject will be set to a new MediaStream containing the VideoTrack's MediaStreamTrack.

Inherited From:

• VideoTrack#attach

Overrides:

• VideoTrack#attach

Returns:

videoElement

Type

HTMLVideoElement

Example

const Video = require('twilio-video');

Video.createLocalVideoTrack().then(function(videoTrack) {
  const videoElement = videoTrack.attach();
  document.body.appendChild(videoElement);
});
  

---

detach()

Detach the VideoTrack from all previously attached HTMLMediaElements.

Inherited From:

• VideoTrack#detach

Overrides:

• VideoTrack#detach

Returns:

mediaElements

Type

Array.<HTMLMediaElement>

Example

const mediaElements = videoTrack.detach();
mediaElements.forEach(mediaElement => mediaElement.remove());
  

---

removeProcessor(processor)

Remove the previously added VideoProcessor using addProcessor API.

Parameters:

Name	Type	Description
processor	VideoProcessor	The VideoProcessor to remove.

Overrides:

• VideoTrack#removeProcessor

Returns:

Type

this

Example

class GrayScaleProcessor {
  constructor(percentage) {
    this.percentage = percentage;
  }
  processFrame(inputFrameBuffer, outputFrameBuffer) {
    const context = outputFrameBuffer.getContext('2d');
    context.filter = `grayscale(${this.percentage}%)`;
    context.drawImage(inputFrameBuffer, 0, 0, inputFrameBuffer.width, inputFrameBuffer.height);
  }
}

const grayscaleProcessor = new GrayScaleProcessor(100);

Array.from(room.participants.values()).forEach(participant => {
  const remoteVideoTrack = Array.from(participant.videoTracks.values())[0].track;
  remoteVideoTrack.addProcessor(grayscaleProcessor);
});

document.getElementById('remove-button').onclick = () => {
  Array.from(room.participants.values()).forEach(participant => {
    const remoteVideoTrack = Array.from(participant.videoTracks.values())[0].track;
    remoteVideoTrack.removeProcessor(grayscaleProcessor);
  });
}

---

setContentPreferences(contentPreferences)

Set the RemoteVideoTrack's content preferences. This method is applicable only for the group rooms and only when connected with videoContentPreferencesMode in video bandwidth profile options set to 'manual'

Parameters:

Name	Type	Description
contentPreferences	VideoContentPreferences	requested preferences.

Returns:

Type

this

---

setPriority(priority)

Update the subscribe Track.Priority of the RemoteVideoTrack.

Parameters:

Name	Type	Argument	Description
priority	Track.Priority	<nullable>	the new subscribe Track.Priority; If null, then the subscribe Track.Priority is cleared, which means the Track.Priority set by the publisher is now the effective priority.

Throws:

RangeError

Returns:

Type

this

---

switchOff()

Request to switch off a RemoteVideoTrack, This method is applicable only for the group rooms and only when connected with clientTrackSwitchOffControl in video bandwidth profile options set to 'manual'

Returns:

Type

this

---

switchOn()

Request to switch on a RemoteVideoTrack, This method is applicable only for the group rooms and only when connected with clientTrackSwitchOffControl in video bandwidth profile options set to 'manual'

Returns:

Type

this

Events

---

dimensionsChanged

The RemoteVideoTrack's dimensions changed.

Parameters:

Name	Type	Description
track	RemoteVideoTrack	The RemoteVideoTrack whose dimensions changed

Overrides:

• VideoTrack#event:dimensionsChanged

---

disabled

The RemoteVideoTrack was disabled, i.e. "paused" (Deprecated only for large group Rooms).

Parameters:

Name	Type	Description
track	RemoteVideoTrack	The RemoteVideoTrack that was disabled

Overrides:

• VideoTrack#event:disabled

Deprecated:

• Use switchedOff (.switchOffReason === "disabled-by-publisher") instead

---

enabled

The RemoteVideoTrack was enabled, i.e. "resumed" (Deprecated only for large group Rooms).

Parameters:

Name	Type	Description
track	RemoteVideoTrack	The RemoteVideoTrack that was enabled

Overrides:

• VideoTrack#event:enabled

Deprecated:

• Use switchedOn instead

---

started

The RemoteVideoTrack started. This means there is enough video data to begin playback.

Parameters:

Name	Type	Description
track	RemoteVideoTrack	The RemoteVideoTrack that started

Overrides:

• VideoTrack#event:started

---

switchedOff

A RemoteVideoTrack was switched off. The media server stops sending media for the RemoteVideoTrack until it is switched back on. Just before the event is raised, isSwitchedOff is set to true and switchOffReason is set to a TrackSwitchOffReason in large group Rooms (switchOffReason is null non-large group Rooms). Also, the mediaStreamTrack property is set to null (only in large group Rooms).

Parameters:

Name	Type	Argument	Description
track	RemoteVideoTrack		The RemoteVideoTrack that was switched off
switchOffReason	TrackSwitchOffReason	<nullable>	The reason the RemoteVideoTrack was switched off

---

switchedOn

A RemoteVideoTrack was switched on.

Parameters:

Name	Type	Description
track	RemoteVideoTrack	The RemoteVideoTrack that was switched on