The RTCRtpSendParameters
dictionary's encodings
property is an RTCRtpEncodingParameters
object providing configuration settings for the encoder being used for the RTCRtpSender
's track
.
Syntax
sendParameters.encodings = encodingParameterList; encodingParameterList = sendParameters.encodings;
Value
An array of objects conforming to the RTCRtpEncodingParameters
dictionary, each of which contains properties which provide settings and parameters that describe and configure a single codec that could be used to encode the track. Each object's properties are:
active
- If
true
, the described encoding is currently actively being used. That is, for RTP senders, the encoding is currently being used to send data, while for receivers, the encoding is being used to decode received data. The default value istrue
. codecPayloadType
- When describing a codec for an
RTCRtpSender
,codecPayloadType
is a single 8-bit byte (or octet) specifying the codec to use for sending the stream; the value matches one from the owningRTCRtpParameters
object'scodecs
parameter. This value can only be set when creating the transceiver; after that, this value is read only. dtx
- Only used for an
RTCRtpSender
whosekind
isaudio
, this property indicates whether or not to use discontinuous transmission (a feature by which a phone is turned off or the microphone muted automatically in the absence of voice activity). The value is taken from the enumerated string typeRTCDtxStatus
. maxBitrate
- An unsigned long integer indicating the maximum number of bits per second to allow for this encoding. Other parameters may further constrain the bit rate, such as the value of
maxFramerate
or transport or physical network limitations. maxFramerate
- A double-precision floating-point value specifying the maximum number of frames per second to allow for this encoding.
ptime
- An unsigned long integer value indicating the preferred duration of a media packet in milliseconds. This is typically only relevant for audio encodings. The user agent will try to match this as well as it can, but there is no guarantee.
rid
- A
DOMString
which, if set, specifies an RTP stream ID (RID) to be sent using the RID header extension. This parameter cannot be modified usingsetParameters()
. Its value can only be set when the transceiver is first created. scaleResolutionDownBy
- Only used for senders whose track's
kind
isvideo
, this is a double-precision floating-point value specifying a factor by which to scale down the video during encoding. The default value, 1.0, means that the sent video's size will be the same as the original. A value of 2.0 scales the video frames down by a factor of 2 in each dimension, resulting in a video 1/4 the size of the original. The value must not be less than 1.0 (you can't use this to scale the video up).
Specifications
Specification | Status | Comment |
---|---|---|
WebRTC 1.0: Real-time Communication Between Browsers The definition of 'RTCRtpSendParameters.encodings' 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.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
encodings | Chrome Full support 69 | Edge Full support ≤79 | Firefox
No support
No
| IE No support No | Opera ? | Safari ? | WebView Android Full support 69 | Chrome Android Full support 69 | Firefox Android
No support
No
| Opera Android ? | Safari iOS ? | Samsung Internet Android Full support 10.0 |
Legend
- Full support
- Full support
- No support
- No support
- Compatibility unknown
- Compatibility unknown
- See implementation notes.
- See implementation notes.