HTMLMediaElement: srcObject property
The srcObject
property of the HTMLMediaElement
interface sets or returns the object which serves as the source of the media associated with the HTMLMediaElement
.
The object can be a MediaStream
, a MediaSource
, a Blob
, or a File
(which inherits from Blob
).
Note: As of March 2020, only Safari has full support for srcObject
, i.e. using MediaSource
, MediaStream
, Blob
, and File
objects as values. Other browsers support MediaStream
objects; until they catch up, consider falling back to creating a URL with URL.createObjectURL()
and assigning it to HTMLMediaElement.src
(see below for an example). In addition, as of version 108 Chromium supports attaching a dedicated worker MediaSource
object by assigning that object's MediaSourceHandle
instance (transferred from the worker) to srcObject
.
Value
A MediaStream
, MediaSource
, Blob
, or File
object (though see the compatibility table for what is actually supported).
Usage notes
Older versions of the Media Source specification required using URL.createObjectURL()
to create an object URL then setting src
to that URL. Now you can just set srcObject
to the MediaStream
directly.
Examples
Basic example
In this example, a MediaStream
from a camera is assigned to a newly-created <video>
element.
const mediaStream = await navigator.mediaDevices.getUserMedia({ video: true });
const video = document.createElement("video");
video.srcObject = mediaStream;
In this example, a new MediaSource
is assigned to a newly-created <video>
element.
const mediaSource = new MediaSource();
const video = document.createElement("video");
video.srcObject = mediaSource;
Supporting fallback to the src property
The examples below support older browser versions that require you to create an object URL and assign it to src
if srcObject
isn't supported.
First, a MediaStream
from a camera is assigned to a newly-created <video>
element, with fallback for older browsers.
const mediaStream = await navigator.mediaDevices.getUserMedia({ video: true });
const video = document.createElement("video");
if ("srcObject" in video) {
video.srcObject = mediaStream;
} else {
video.src = URL.createObjectURL(mediaStream);
}
Second, a new MediaSource
is assigned to a newly-created <video>
element, with fallback for older browsers and browsers that don't yet support assignment of MediaSource
directly.
const mediaSource = new MediaSource();
const video = document.createElement("video");
if ("srcObject" in video) {
try {
video.srcObject = mediaSource;
} catch (err) {
if (err.name !== "TypeError") {
throw err;
}
video.src = URL.createObjectURL(mediaSource);
}
} else {
video.src = URL.createObjectURL(mediaSource);
}
Constructing a MediaSource
in a worker and passing it to the main thread to play
The MediaSource.handle
property can be accessed inside a dedicated worker and the resulting MediaSourceHandle
object is then transferred over to the thread that created the worker (in this case the main thread) via a postMessage()
call:
let mediaSource = new MediaSource();
let handle = mediaSource.handle;
postMessage({ arg: handle }, [handle]);
mediaSource.addEventListener("sourceopen", () => {
});
Over in the main thread, we receive the handle via a message
event handler, attach it to a <video>
via its HTMLMediaElement.srcObject
property, and play
the video:
worker.addEventListener("message", (msg) => {
let mediaSourceHandle = msg.data.arg;
video.srcObject = mediaSourceHandle;
video.play();
});
Note: MediaSourceHandle
s cannot be successfully transferred into or via a shared worker or service worker.
Specifications
Browser compatibility
|
Desktop |
Mobile |
|
Chrome |
Edge |
Firefox |
Internet Explorer |
Opera |
Safari |
WebView Android |
Chrome Android |
Firefox for Android |
Opera Android |
Safari on IOS |
Samsung Internet |
srcObject |
108Support added for MediaSourceHandle objects transferred from dedicated workers where they were obtained from MediaSource.handle (see bug 878133).52Support added for MediaStream objects (see bug 506273).
|
108Support added for MediaSourceHandle objects transferred from dedicated workers where they were obtained from MediaSource.handle (see bug 878133).79Support added for MediaStream objects (see bug 506273).
|
42Only supports MediaStream objects (see bug 886194). 18–58 |
No |
94Support added for MediaSourceHandle objects transferred from dedicated workers where they were obtained from MediaSource.handle (see bug 878133).39Support added for MediaStream objects (see bug 506273).
|
11 |
108Support added for MediaSourceHandle objects transferred from dedicated workers where they were obtained from MediaSource.handle (see bug 878133).52Support added for MediaStream objects (see bug 506273).
|
108Support added for MediaSourceHandle objects transferred from dedicated workers where they were obtained from MediaSource.handle (see bug 878133).52Support added for MediaStream objects (see bug 506273).
|
42Only supports MediaStream objects (see bug 886194). 18–58 |
73Support added for MediaSourceHandle objects transferred from dedicated workers where they were obtained from MediaSource.handle (see bug 878133).41Support added for MediaStream objects (see bug 506273).
|
11 |
21.0Support added for MediaSourceHandle objects transferred from dedicated workers where they were obtained from MediaSource.handle (see bug 878133).6.0Support added for MediaStream objects (see bug 506273).
|