RTCRtpSender.setParameters()

The setParameters() method of the RTCRtpSender interface applies changes the configuration of sender's track, which is the MediaStreamTrack for which the RTCRtpSender is responsible.

In other words, setParameters() updates the configuration of the RTP transmission as well as the encoding configuration for a specific media track on the WebRTC connection.

Syntax

var promise = rtcRtpSender.setParameters(parameters)

Parameters

parameters

An object conforming with the RTCRtpSendParameters dictionary, specifying options for the RTCRtpSender; these include potential codecs that could be use for encoding the sender's track. The available options are:

degradationPreference

Specifies the preferred way the WebRTC layer should handle optimizing bandwidth against quality in constrained-bandwidth situations; the value comes from the RTCDegradationPreference enumerated string type, and the default is balanced.

encodings

An array of RTCRtpEncodingParameters objects, each specifying the parameters for a single codec that could be used to encode the track's media.

priority

A string from the RTCPriorityType enumerated type which indicates the encoding's priority. The default value is low.

transactionId

A string containing a unique ID for the last set of parameters applied; this value is used to ensure that setParameters() can only be called to alter changes made by a specific previous call to getParameters().

Return value

A Promise that resolves when the RTCRtpSender.track property is updated with the given parameters.

Exceptions

If an error occurs, the returned promise is rejected with the appropriate exception from the list below.

InvalidModificationError

One of the following problems was detected:

• The number of encodings specified in the parameters object's encodings property does not match the number of encodings currently listed for the RTCRtpSender. You cannot change the number of encoding options once the sender has been created.
• The order of the specified encodings has changed from the current list's order.
• An attempt has been made to alter a property that cannot be changed after the sender is first created.

InvalidStateError

The transceiver of which the RTCRtpSender is a part is not running, or has no parameters to set.

OperationError

Any error condition which occurs that isn't covered by one of the other error codes results in an OperationError.

RangeError

The value specified for scaleResolutionDownBy is less than 1.0, which would result in scaling up rather than down, which is not allowed; or one or more of the specified encodings' maxFramerate values is less than 0.0.

In addition, if a WebRTC error occurs while configuring or accessing the media, an RTCError is thrown with its errorDetail set to hardware-encoder-error.

Specifications

Browser compatibility

See also

• WebRTC API
• Codecs used by WebRTC
• Web media technologies