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Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
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 HTMLMediaElement.seekToNextFrame() method asynchronously advances the the current play position to the next frame in the media.
This non-standard method is part of an experimentation process around support for non-real-time access to media for tasks including filtering, editing, and so forth. You should not use this method in production code, because its implementation may change—or be removed outright—without notice. You are, however, invited to experiment with it.
This method lets you access frames of video media without the media being performed in real time. This also lets you access media using frames as a seek unit rather than timecodes (albeit only by seeking one frame at a time until you get to the frame you want). Possible uses for this method include filtering and editing of video content.
This method returns immediately, returning a Promise, whose fulfillment handler is called when the seek operation is complete. In addition, a seeked event is sent to let interested parties know that a seek has taken place. If the seek fails because the media is already at the last frame, a seeked event occurs, followed immediately by an ended event.
If there is no video on the media element, or the media isn't seekable, nothing happens.
Syntax
var seekCompletePromise = HTMLMediaElement.seekToNextFrame(); HTMLMediaElement.seekToNextFrame();
Return value
A Promise which is fulfilled once the seek operation has completed.
Firefox 49 returns undefined instead of a promise, and performs the seek operation synchronously.
Specifications
Not part of any specification.
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | No support | 49 (49)[1][2] | No support | No support | No support |
Returns Promise |
No support | 50 (50)[2][3] | No support | No support | No support |
| Feature | Android | Android Webview | Firefox Mobile (Gecko) | B2G OS | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
|---|---|---|---|---|---|---|---|---|
| Basic support | No support | No support | 49.0 (49)[1][2] | ? | No support | No support | No support | No support |
Returns Promise |
No support | No support | 50.0 (50)[2][3] | ? | No support | No support | No support | No support |
[1] In Firefox 49, the seekToNextFrame() method returns undefined and generates a seeked event once the seek operation is completed.
[2] In Firefox, this method is only available if the preference media.seekToNextFrame.enabled is set to "true". In Firefox 49, this value always defaults to "false". Starting in Firefox 50, this value defaults to "true" in non-release builds (that is, in Nightly, Developer Edition, and Beta releases).
[3] Starting in Firefox 50, seekToNextFrame() returns a Promise, whose fulfillment handler is called once the seek is complete. The seek operation itself is performed asynchronously.