Web/API/RTCRtpEncodingParameters/scaleResolutionDownBy

The RTCRtpEncodingParameters dictionary's scaleResolutionDownBy property can be used to specify a factor by which to reduce the size of a video track during encoding.

This property is only available for tracks whose kind is video.

Syntax

rtpEncodingParameters.scaleResolutionDownBy = scalingFactor;

rtpEncodingParameters = {
  scaleResolutionDownBy: scalingFactor
};

Value

A double-precison floating-point number specifying the amount by which to reduce the size of the video during encoding. The default value, 1.0, means that the video will be encoded at its original size. A value of 2.0 would reduce the size of the video by a factor of 2 both horizontally and vertically, resulting in a video 25% the original size.

A value less than 1.0 would cause the video to get larger rather than smaller, which is not the intent of this property. Therefore, specifying a value less than 1.0 is not permitted and will cause a RangeError exception to be thrown by RTCPeerConnection.addTransceiver() or RTCRtpSender.setParameters().

Specifications

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

Browser compatibility

The compatibility table in 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
scaleResolutionDownBy	Chrome Full support 74	Edge No support No	Firefox Full support 46	IE No support No	Opera ?	Safari ?	WebView Android Full support 74	Chrome Android Full support 74	Firefox Android Full support 46	Opera Android ?	Safari iOS ?	Samsung Internet Android Full support 11.0

Legend

Full support  

Full support

No support  

No support

Compatibility unknown  

Compatibility unknown

RTCRtpEncodingParameters.scaleResolutionDownBy by Mozilla Contributors is licensed under CC-BY-SA 2.5.