HTMLMediaElement.playbackRate - Web APIs 编辑

The HTMLMediaElement.playbackRate property sets the rate at which the media is being played back. This is used to implement user controls for fast forward, slow motion, and so forth. The normal playback rate is multiplied by this value to obtain the current rate, so a value of 1.0 indicates normal speed.

If playbackRate is negative, the media is not played backwards.

The audio is muted when the fast forward or slow motion is outside a useful range (for example, Gecko mutes the sound outside the range 0.25 to 4.0).

The pitch of the audio is corrected by default and is the same for every speed. Some browsers implement the non-standard HTMLMediaElement.preservesPitch property to control this.

Syntax

// video
video.playbackRate = 1.5;
// audio
audio.playbackRate = 1.0;

Value

A double. 1.0 is "normal speed," values lower than 1.0 make the media play slower than normal, higher values make it play faster. (Default: 1.0)

Example

var obj = document.createElement('video');
console.log(obj.playbackRate); // Expected Output: 1

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• The interface defining it, HTMLMediaElement.