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URL.createObjectURL

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The URL.createObjectURL() static method creates a DOMString containing an URL representing the object given in parameter. The URL lifetime is tied to the document in the window on which it was created. The new object URL represents the specified File object or Blob object.

The use of a MediaStream object as an input to this method is in the process of being deprecated. Discussions are ongoing about whether or not it should be removed outright. As such, you should try to avoid using this method with MediaStreams, and should use HTMLMediaElement.srcObject() instead.

Note: This feature is available in Web Workers.

Syntax

objectURL = URL.createObjectURL(object);

Parameters

object
A File object or a Blob object to create a object URL for.

Example

See Using object URLs to display images.

Notes

Each time you call createObjectURL(), a new object URL is created, even if you've already created one for the same object. Each of these must be released by calling URL.revokeObjectURL() when you no longer need them. Browsers will release these automatically when the document is unloaded; however, for optimal performance and memory usage, if there are safe times when you can explicitly unload them, you should do so. E.g. Failing to do so on URLs created from MediaStreams may leave the browser's camera light on longer than necessary.

Note that there's no need to create URLs out of a MediaStream, as stream objects may be assigned directly to playback elements using HTMLMediaElement.srcObject. The ability to use a MediaStream as the value of object is being deprecated.

Specifications

Specification Status Comment
File API
The definition of 'URL' in that specification.
Working Draft Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 8 [1]
23
4.0 (2) 10 15 6 [1]
7
In a Web Worker 10 [1]
23
21 (21) 11 15 6 [1]
7
Feature Chrome for Android Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support 18 [1] 4.0 [1] 14.0 (14) ? 15 [1] 6.0 [1]
In a Web Worker 18 [1] (Yes) [1] 14.0 (14) ? 15 [1] 6.0 [1]

[1] With URL prefixed as webkitURL

See also

© 2005–2017 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/URL/createObjectURL