Setting the resolution and frame rate for a video

You can set the frame rate and resolution for a publisher's stream by setting a resolution property of the options you pass into the OT.initPublisher() method. See Setting the video resolution of a stream and Setting the frame rate of a stream.

You can set the frame rate and resolution for a subscriber's stream by setting the preferredFrameRate and preferredResolution properties of the options you pass into the session.subscribe() method. We recommend setting the preferreResolution option to "auto" to optimize the CPU and network usage. The "auto" option is a beta feature. See Setting the preferred frame rate and resolution

Switching the camera used by a Publisher

You can switch the video input device (camera) used as the video source for a Publisher by calling the Publisher.cycleVideo() or Publisher.setVideoSource() method:

Publisher.cycleVideo()

The Publisher.cycleVideo() method lets you cycle through the available video sources (cameras). For example, on a mobile device you can switch between the front and back camera. The method returns a promise that resolves when the operation completes successfully. The promise resolves with an object that has a deviceId property set to the device ID of the camera used:

If there is an error, the promise is rejected. This can occur in the following conditions:

• The user denied access to the video input device.
• The publisher is not using a camera video source. This method does not work for a screen-sharing publisher, a publisher that uses a MediaStreamTrack source, or a publisher that does not include a video track (an audio-only publisher).
• There are no video input devices (cameras) available.
• There was an error acquiring video from the video input device.

Note that this method only works for a publisher that is using a camera video source.

Publisher.setVideoSource()

The Publisher.setVideoSource() method lets you pass in the device ID of the new video source (camera). The method returns a promise that resolves when the operation completes:

The following will result in errors:

• If the videoSourceId parameter is not a string or the device ID for a valid video input device, the promise will reject with an error with the name property set to 'OT_INVALID_VIDEO_SOURCE'.
• If the publisher does not currently use a camera input, the promise will reject with an error with the name property set to 'OT_SET_VIDEO_SOURCE_FAILURE'.

You can use the OT.getDevices() method to enumerate the available video input devices (and get their device IDs).

You can use the Publisher.getVideoSource() method to get the current video source and its device ID (if it is a video input device).

Mirroring the local display of a Publisher's video

You can set the mirror property of the options passed into the OT.initPublisher() method to have the publisher's locally rendered video mirrored (true) or not (false). By default, video is mirrored for a publisher that has a camera video source, and not mirrored for a screen-sharing video.

This setting only affects the rendered video in the publisher's client application. It has no effect on the video in subscribing clients.