MediaStreamTrack
The MediaStreamTrack
interface represents a single media track within a stream; typically, these are audio or video tracks, but other track types may exist as well.
Properties
In addition to the properties listed below, MediaStreamTrack
has constrainable properties which can be set using applyConstraints()
and accessed using getConstraints()
and getSettings()
. See "Capabilities and constraints" in Media Capture and Streams API (Media Streams) to learn how to correctly work with constrainable properties. Not doing so correctly will result in your code being unreliable.
MediaStreamTrack.enabled
- A Boolean value with a value of
true
if the track is enabled, that is allowed to render the media source stream; orfalse
if it is disabled, that is not rendering the media source stream but silence and blackness. If the track has been disconnected, this value can be changed but has no more effect. MediaStreamTrack.id
Read only- Returns a
DOMString
containing a unique identifier (GUID) for the track; it is generated by the browser. MediaStreamTrack.kind
Read only- Returns a
DOMString
set to"audio"
if the track is an audio track and to"video"
, if it is a video track. It doesn't change if the track is deassociated from its source. MediaStreamTrack.label
Read only- Returns a
DOMString
containing a user agent-assigned label that identifies the track source, as in"internal microphone"
. The string may be left empty and is empty as long as no source has been connected. When the track is deassociated from its source, the label is not changed. MediaStreamTrack.muted
Read only- Returns a Boolean value indicating whether the track is muted.
MediaStreamTrack.readonly
Read only- Returns a Boolean value with a value of
true
if the track is readonly (such a video file source or a camera that settings can't be modified),false
otherwise. MediaStreamTrack.readyState
Read only- Returns an enumerated value giving the status of the track. This will be one of the following values:
"live"
which indicates that an input is connected and does its best-effort in providing real-time data. In that case, the output of data can be switched on or off using theMediaStreamTrack.enabled
attribute."ended"
which indicates that the input is not giving any more data and will never provide new data.
MediaStreamTrack.remote
Read only- Returns a Boolean with a value of
true
if the track is sourced by aRTCPeerConnection
,false
otherwise.
Event handlers
MediaStreamTrack.onstarted
- Is a
EventHandler
containing the action to perform when anstarted
event is fired on the object, that is when a newMediaStreamTrack
object is added. MediaStreamTrack.onmute
- Is a
EventHandler
containing the action to perform when anmute
event is fired on the object, that is when the streaming is terminating. MediaStreamTrack.onunmute
- Is a
EventHandler
containing the action to perform when anunmute
event is fired on the object, that is when aMediaStreamTrack
object is removed from it. MediaStreamTrack.onoverconstrained
- Is a
EventHandler
containing the action to perform when anoverconstrained
event is fired on the object, that is when aMediaStreamTrack
object is removed from it. MediaStreamTrack.onended
- Is a
EventHandler
containing the action to perform when anended
event is fired on the object, that is when aMediaStreamTrack
object is removed from it.
Methods
applyConstraints()
- Lets the application specify the ideal and/or ranges of acceptable values for any number of the available constrainable properties of the
MediaStreamTrack
. clone()
- Returns a duplicate of the
MediaStreamTrack
. getCapabilities()
- Returns the a list of constrainable properties available for the
MediaStreamTrack
. getConstraints()
- Returns a
MediaTrackConstraints
object containing the currently set constraints for the track; the returned value matches the constraints last set usingapplyConstraints()
. getSettings()
- Returns a
MediaTrackSettings
object containing the current values of each of theMediaStreamTrack
's constrainable properties. stop()
- Stops playing the source associated to the track, both the source and the track are deassociated. The track state is set to
ended
.
Specifications
Specification | Status | Comment |
---|---|---|
Media Capture and Streams The definition of 'MediaStreamTrack' in that specification. |
Editor's Draft | Initial definition |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
Basic support | (Yes) | 22 (22) | No support | No support | ? |
stop() |
(Yes) | 34 (34) | ? | ? | ? |
kind, id, label |
(Yes) | 22 (22) | ? | ? | ? |
clone() |
(Yes) | 48 (48) | ? | ? | ? |
onended, readyState |
(Yes) | 50 (50) | ? | ? | ? |
enabled |
(Yes) | 23 (23) | (Yes) | (Yes) | (Yes) |
muted , onmute , onunmute |
(Yes) | No support | ? | ? | ? |
remote |
48.0 | No support | ? | ? | ? |
getConstraints() , getSettings() |
53.0 | 50 (50) | ? | ? | ? |
onoverconstrained |
? | No support | ? | ? | ? |
getSources() |
(Yes) | No support | ? | ? | ? |
Feature | Android | Android Webview | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile | Chrome for Android |
---|---|---|---|---|---|---|---|
Basic support | ? | (Yes) | 22.0 (22) | No support | No support | ? | (Yes) |
stop() |
? | (Yes) | 34.0 (34) | No support | ? | ? | (Yes) |
kind, id, label |
(Yes) | 22 (22) | ? | ? | ? | ? | ? |
clone() |
(Yes) | 48.0 (48) | ? | ? | ? | ? | ? |
onended, readyState |
(Yes) | 50.0 (50) | ? | ? | ? | ? | ? |
enabled |
(Yes) | 23.0 (23) | (Yes) | (Yes) | (Yes) | ? | ? |
muted , onmute , onunmute |
(Yes) | No support | ? | ? | ? | ? | ? |
remote |
No support | 48.0 | No support | No support | ? | ? | 48.0 |
getConstraints() , getSettings() |
No support | 53.0 | 50 (50) | No support | ? | ? | 52.0 |
onoverconstrained |
? | No support | ? | ? | ? | ? | ? |
getSources() |
(Yes) | No support | ? | ? | ? | ? | ? |
See also
- Media Capture and Streams API
MediaStream
AudioStreamTrack
andVideoStreamTrack
- Using the MediaStream API
License
© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/mediastreamtrack