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RTCRTPParameters

The corresponding JS API docs is here getParameters.

Encoding configuration of RTP

Properties#

  • transactionId:A string containing a unique ID. This value is used to ensure that setParameters() can only be called to modify the parameters returned by a specific previous call to get Parameters. This parameter cannot be changed by the caller.

  • rtcp:A dictionary containing information about the RTCP configuration. This parameter is optional and can be omitted if RTCP is not needed.

  • headerExtensions:An array of zero or more RTP header extensions, each identifying an extension supported by the sender or receiver.

  • encodings:An array of zero or more RTP encodings, each specifying a media stream and its parameters. The properties of the objects include:

    • rid:A string which, If non-null, this represents the RID thatidentifies this encoding layer. RIDs are used to identify layers in simulcast.

    • active:true (the default) if the encoding is being sent, false if it is not being sent or used.

    • maxBitrate:The maximum bitrate (in bits per second) that the encoding can use. If non-null, this represents the Transport IndependentApplication Specific maximum bandwidth defined in RFC3890. If null, there is no maximum bitrate.

    • maxFramerate:The maximum frame rate (in frames per second) that the encoding can use.

    • minBitrate:The minimum bitrate (in bits per second) that the encoding can use.

    • numTemporalLayers:The number of temporal layers to be used for this encoding(default is 1).

    • scaleResolutionDownBy:The factor by which the resolution of the video should be scaled down before encoding (default is 1.0). If non-null, scale the width and height down by this factor for video. If null, the implementation default scaling factor will be used.

    • ssrc:SSRC to be used by this encoding.Can't be changed between getParameters/setParameters.

    • scalabilityMode:The scalability mode to be used for this encoding. Can be "L1T3" or "L1T2".

  • codecs:An array of zero or more RTCRtpCodecParameters objects, each specifying a codec supported by the sender or receiver. Each codec object in the array may have the following properties:

    • payloadType:Payload type used to identify this codec in RTP packets.

    • name:Name used to identify the codec. Equivalent to MIME subtype.

    • kind:The media type of this codec. Equivalent to MIME top-level type.

    • clockRate:Clock rate in Hertz.

    • numChannels:The number of audio channels used. Set to null for video codecs.

  • degradationPreference:Specifies the preferred way the WebRTC layer should handle optimizing bandwidth against quality in constrained-bandwidth situations.The possible values are

    • DISABLED

    • MAINTAIN_FRAMERATE

    • MAINTAIN_RESOLUTION

    • BALANCED

    The default value is BALANCED.