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Media Streams API

The Media Capture and Streams API, often called the Media Streams API or simply MediaStream API, is an API related to WebRTC which provides support for streaming audio and video data. It provides the interfaces and methods for working with the streams and their constituent tracks, the constraints associated with data formats, the success and error callbacks when using the data asynchronously, and the events that are fired during the process.

Basic concepts

The API is based on the manipulation of a MediaStream object representing a flux of audio- or video-related data. See an example in Get the video.

A MediaStream consists of zero or more MediaStreamTrack objects, representing various audio or video tracks. Each MediaStreamTrack may have one or more channels. The channel represents the smallest unit of a media stream, such as an audio signal associated with a given speaker, like left or right in a stereo audio track.

MediaStream objects have a single input and a single output. A MediaStream object generated by getUserMedia() is called local, and has as its source input one of the user's cameras or microphones. A non-local MediaStream may be representing to a media element, like <video> or <audio>, a stream originating over the network, and obtained via the WebRTC RTCPeerConnection API, or a stream created using the Web Audio API MediaStreamAudioSourceNode. The output of the MediaStream object is linked to a consumer. It can be a media elements, like <audio> or <video>, the WebRTC RTCPeerConnection API or a Web Audio API MediaStreamAudioDestinationNode.

Reference

In these reference articles, you'll find the fundamental information you'll need to know about each of the interfaces and events that make up the Media Capture and Streams API.

Interfaces

Early versions of the Media Capture and Streams API specification included separate AudioStreamTrack and VideoStreamTrack interfaces—each based upon MediaStreamTrack—which represented streams of those types. These no longer exist, and you should update any existing code to instead use MediaStreamTrack directly.

Events

Guides and tutorials

The articles below provide additional guidance and how-to information that will help you learn to use the API, and how to perform specific tasks that you may wish to handle.

Capabilities, constraints, and settings: The twin concepts of constraints and capabilities let the browser and Web site or app exchange information about what constrainable properties the browser's implementation supports and what values it supports for each one. This article discusses capabilities and constraints, as well as media settings, and includes an example we call the Constraint Exerciser.

Browser compatibilityUpdate compatibility data on GitHub

	Desktop
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari
Basic support	Yes	Yes	Yes	No	No	?
`MediaStream`	55	Yes	44	No	42	No
`active`	Yes	12	52	?	?	?
`ended`	? — 54 ? — 54 Deprecated in Chrome 52.	?	No	?	? — 39	?
`id`	? — 54	12	41	?	? — 39	?
`onaddtrack`	Yes	12	50	?	?	?
`onremovetrack`	Yes	12	No	?	?	?
`addTrack`	Yes	12	44	?	?	?
`clone`	Yes	12	48	?	?	?
`getAudioTracks`	Yes	12	?	?	Yes	?
`getTrackById`	Yes	12	49	No	?	?
`getTracks`	Yes	12	?	?	Yes	?
`getVideoTracks`	Yes	12	?	?	Yes	?
`removeTrack`	Yes	12	?	?	Yes	?
`label`	? — 54 ? — 54 Deprecated in Chrome 45.	?	?	No	No	?
`stop`	No	13	?	No	No	?

	Mobile
	Android webview	Chrome for Android	Edge Mobile	Firefox for Android	Opera for Android	iOS Safari	Samsung Internet
Basic support	Yes	Yes	Yes	?	No	?	Yes
`MediaStream`	55	55	Yes	42	?	No	6.0
`active`	Yes	Yes	Yes	52	?	?	Yes
`ended`	? — 54 ? — 54 Deprecated in Chrome 52.	? — 54 ? — 54 Deprecated in Chrome 52.	Yes	No	? — 39	?	Yes
`id`	? — 54	? — 54	Yes	41	? — 39	?	Yes
`onaddtrack`	Yes	Yes	Yes	50	?	?	Yes
`onremovetrack`	Yes	Yes	Yes	No	?	?	Yes
`addTrack`	Yes	Yes	Yes	No	?	?	Yes
`clone`	Yes	Yes	Yes	48	?	?	Yes
`getAudioTracks`	Yes	Yes	Yes	?	?	?	Yes
`getTrackById`	Yes	Yes	Yes	49	?	?	Yes
`getTracks`	Yes	Yes	Yes	?	?	?	Yes
`getVideoTracks`	Yes	Yes	Yes	?	?	?	Yes
`removeTrack`	Yes	Yes	?	?	?	?	Yes
`label`	? — 54 ? — 54 Deprecated in Chrome 45.	? — 54 ? — 54 Deprecated in Chrome 45.	?	?	No	?	Yes
`stop`	No	No	?	?	No	?	No