Web/API/RTCRtpReceiver/getSynchronizationSources

The getSynchronizationSources() method of the RTCRtpReceiver interface returns an array of RTCRtpContributingSource instances, each corresponding to one SSRC (synchronization source) identifier received by the current RTCRtpReceiver in the last ten seconds.

Syntax

var rtcRtpContributingSources = rtcRtpReceiver.getContributingSources()

Parameters

None.

Return value

An array of RTCRtpSynchronizationSource instances. Each instance describes one of the synchronization sources that provided data to the incoming stream in the past ten seconds.

As you'll see in the documentarion for RTCRtpSynchronizationSource, it inherits the properties of RTCRtpContributingSource, including timestamp, source, and audioLevel.

The synchronization source objects add a voiceActivityFlag property, which indicates if the last RTP packet received contained voice activity.

Specifications

Specification	Status	Comment
WebRTC 1.0: Real-time Communication Between BrowsersThe definition of 'getSynchronizationSources()' in that specification.	Candidate Recommendation	Initial definition.

Browser compatibility

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
getSynchronizationSources	Chrome Full support 73	Edge Full support ≤79	Firefox Full support 59	IE No support No	Opera Full support 60	Safari ?	WebView Android Full support 73	Chrome Android Full support 73	Firefox Android Full support 59 Disabled' Full support 59 Disabled' Disabled' From version 59: this feature is behind the media.peerconnection.rtpsourcesapi.enable preference (needs to be set to true). To change preferences in Firefox, visit about:config.	Opera Android Full support 52	Safari iOS ?	Samsung Internet Android Full support 11.0
Audio tracks supported	Chrome Full support 73	Edge Full support 79	Firefox Full support 59	IE No support No	Opera Full support 60	Safari ?	WebView Android Full support 73	Chrome Android Full support 73	Firefox Android Full support 59 Disabled' Full support 59 Disabled' Disabled' From version 59: this feature is behind the media.peerconnection.rtpsourcesapi.enable preference (needs to be set to true). To change preferences in Firefox, visit about:config.	Opera Android Full support 52	Safari iOS ?	Samsung Internet Android Full support 11.0
Video tracks supported	Chrome Full support 73	Edge Full support ≤79	Firefox Full support 68	IE No support No	Opera Full support 60	Safari ?	WebView Android Full support 73	Chrome Android Full support 73	Firefox Android Full support 68 Disabled' Full support 68 Disabled' Disabled' From version 68: this feature is behind the media.peerconnection.rtpsourcesapi.enable preference (needs to be set to true). To change preferences in Firefox, visit about:config.	Opera Android Full support 52	Safari iOS ?	Samsung Internet Android Full support 11.0

Legend

Full support  

Full support

No support  

No support

Compatibility unknown  

Compatibility unknown

User must explicitly enable this feature.'

User must explicitly enable this feature.

RTCRtpReceiver.getSynchronizationSources() by Mozilla Contributors is licensed under CC-BY-SA 2.5.