mozilla
Your Search Results

    HTMLMediaElement

    この記事はまだ日本語に翻訳されていません。MDN の翻訳はボランティアによって行われています。是非 MDN に登録し、私たちの力になって下さい。

    The HTMLMediaElement interface adds to HTMLElement the properties and methods needed to support basic media-related functionality that's common to both audio and video. The HTMLVideoElement and HTMLAudioElement elements inherit this interface. special properties and methods (beyond the properties and methods available for all children of HTMLElement), that are common to all media-related objects.

    Properties

    Inherits properties from its parent, HTMLElement.

    Name Type Description
    audioTracks AudioTrackList Represents the list of AudioTrack objects contained in the element.
    autoplay Boolean Reflects the autoplay HTML attribute, indicating whether playback should automatically begin as soon as enough media is available to do so without interruption.
    buffered Read only TimeRanges The ranges of the media source that the browser has buffered (if any) at the moment the buffered property is accessed. The returned TimeRanges object is normalized.
    controller MediaController Represents the media controller associated to the element, or null if none is linked to it.
    controls Boolean Reflects the controls HTML attribute, indicating whether user interface items for controlling the resource should be displayed.
    crossOrigin DOMString The CORS setting for this image element. See CORS settings attributes for details.
    currentSrc Read only DOMString The absolute URL of the chosen media resource (if, for example, the server selects a media file based on the resolution of the user's display), or an empty string if the networkState is EMPTY.
    currentTime double The current playback time, in seconds. Setting this value seeks the media to the new time.
    defaultMuted Boolean Reflects the muted HTML attribute, indicating whether the media element's audio output should be muted by default. This property has no dynamic effect, to mute and unmute the audio output, use the muted property.
    defaultPlaybackRate double The default playback rate for the media. 1.0 is "normal speed," values lower than 1.0 make the media play slower than normal, higher values make it play faster. The value 0.0 is invalid and throws a NOT_SUPPORTED_ERR exception.
    duration Read only double The length of the media in seconds, or zero if no media data is available.  If the media data is available but the length is unknown, this value is NaN.  If the media is streamed and has no predefined length, the value is Inf.
    ended Read only Boolean Indicates whether the media element has ended playback.
    error Read only MediaError The MediaError object for the most recent error, or null if there has not been an error.
    initialTime Read only double The initial playback position in seconds.
    loop Boolean Reflects the loop HTML attribute, indicating whether the media element should start over when it reaches the end.
    mediaGroup DOMString Reflects the mediagroup HTML attribute, indicating the name of the group of elements it belongs to. A group of media elements shares a common controller.
    mozAudioChannelType DOMString Can be used to set the audio channel that the sound coming from an <audio> or <video> element will play in, on a Firefox OS device. See Using the AudioChannels API for more details.
    mozChannels Read only long The number of channels in the audio resource (e.g., 2 for stereo).
    mozFrameBufferLength long

    Indicates the number of samples that will be returned in the framebuffer of each MozAudioAvailable event. This number is a total for all channels, and by default is set to be the number of channels * 1024 (e.g., 2 channels * 1024 samples = 2048 total).

    The mozFrameBufferLength property can be set to a new value, for lower latency, or larger amounts of data, etc. The size given must be a number between 512 and 16384. Using any other size results in an exception being thrown. The best time to set a new length is after the loadedmetadata event fires, when the audio info is known, but before the audio has started or MozAudioAvailable events have begun firing.

    mozSampleRate Read only long The number of samples per second that will be played. For example, 44100 samples per second is the sample rate used by CD audio.
    mozSrcObject MediaStream Lets you set or get the Media Stream to be played or being played.
    muted Boolean true if the audio is muted, and false otherwise.
    networkState unsigned short The current state of fetching the media over the network.
    Constant Value Description
    NETWORK_EMPTY 0 There is no data yet.  The readyState is also HAVE_NOTHING.
    NETWORK_IDLE 1  
    NETWORK_LOADING 2 The media is loading.
    NETWORK_NO_SOURCE[1] 3  
    paused Read only Boolean Indicates whether the media element is paused.
    playbackRate double

    The current 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 the playbackRate is negative, the media is played backwards.
    The audio is muted when the media plays backwards or if the fast forward or slow motion is outside a useful range (E.g. Gecko mute the sound outside the range 0.25 and 5.0).

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

    played Read only TimeRanges The ranges of the media source that the browser has played, if any.
    preload DOMString Reflects the preload HTML attribute, indicating what data should be preloaded, if any. Possible values are: none, metadata, auto. See preload attribute documentation for details.
    readyState Read only unsigned short The readiness state of the media.
    Constant Value Description
    HAVE_NOTHING 0 No information is available about the media resource.
    HAVE_METADATA 1 Enough of the media resource has been retrieved that the metadata attributes are initialized.  Seeking will no longer raise an exception.
    HAVE_CURRENT_DATA 2 Data is available for the current playback position, but not enough to actually play more than one frame.
    HAVE_FUTURE_DATA 3 Data for the current playback position as well as for at least a little bit of time into the future is available (in other words, at least two frames of video, for example).
    HAVE_ENOUGH_DATA 4 Enough data is available—and the download rate is high enough—that the media can be played through to the end without interruption.
    seekable Read only TimeRanges The time ranges that the user is able to seek to, if any.
    seeking Read only Boolean Indicates whether the media is in the process of seeking to a new position.
    src DOMString Reflects the src HTML attribute, containing the URL of a media resource to use. Gecko implements a similar functionality for streams: mozSrcObject.
    textTracks TextTrackList Represents the list of TextTrack objects contained in the element.
    videoTracks VideoTrackList Represents the list of VideoTrack objects contained in the element.

    Note: Yet Gecko supports only single track playback, and the parsing of tracks' metadata is only available for media with Ogg container foramt.

    volume double The audio volume, from 0.0 (silent) to 1.0 (loudest).

    Methods

    Inherits methods from its parent, HTMLElement.

    Name & Arguments Return Description
    canPlayType(in DOMString type)

    DOMString

    • probably: if the specified type appears to be playable.
    • maybe: if it's impossible to tell whether the type is playable without playing it.
    • The empty string: if the specified type definitely cannot be played.
    Determines whether the specified media type can be played back.

    Note: Previously canPlayType('video/webm') returned 'probably'. Starting with Gecko 28 (Firefox 28 / Thunderbird 28 / SeaMonkey 2.25 / Firefox OS 1.3), it returns 'maybe'. (bug 884275)

    fastSeek(double time) void Directly seek to the given time.
    load() void Reset the media element and restart selecting the media resource.  Any pending events are discarded.  How much media data is fetched is still affected by the preload attribute.  This method can be useful for releasing resources after any src attribute and source element descendants have been removed.  Otherwise, it is usually unnecessary to use this method, unless required to rescan source element children after dynamic changes.
    mozGetMetadata() Object The mozGetMetadata method returns a javascript object whose properties represent metadata from the playing media resource as {key: value} pairs. A separate copy of the data is returned each time the method is called.
    This method must be called after the loadedmetadata event fires.
    mozLoadFrom(HTMLMediaElement other) void This method, available only in old Mozilla's implementation, loads data from another media element. This works similarly to load() except that instead of running the normal resource selection algorithm, the source is simply set to the other element's currentSrc.
    This is optimized so this element gets access to all of the other element's cached and buffered data; in fact, the two elements share downloaded data so that data downloaded by either element is available to both.
    pause() void Pauses the media playback.
    play() void Begins playback of the media.

    Events

    Audio and Video elements can fire quite a few different events.

    Specifications

    Specification Status Comment
    WHATWG HTML Living Standard
    The definition of 'HTMLMediaElement' in that specification.
    Living Standard No change from HTML5
    HTML5
    The definition of 'HTMLMediaElement' in that specification.
    Recommendation Initial definition.

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
    Basic support (Yes) 3.5 (1.9.1) [1] 9 ? ?
    buffered property (Yes) 4.0 (2.0) 9 ? ?
    defaultMuted property (Yes) 11.0 (11.0) ? ? ?
    loop property (Yes) 11.0 (11.0) 9 ? ?
    seekable property (Yes) 8.0 (8.0) 9 ? ?
    defaultPlaybackRate property (Yes) 20.0 (20.0) 9 ? ?
    playbackRate property (Yes) 20.0 (20.0) 9 ? ?
    preservesPitch property (Yes)webkit 20.0 (20.0)moz Not supported Not supported Not supported
    preload property (Yes) 4.0 (2.0) (implemented autobuffer previously) ? ? ?
    played property (Yes) 15.0 (15.0) ? ? ?
    crossOrigin property (Yes) 12.0 (12.0) as crossorigin
    12.0 (12.0)
     
    ? ? ?
    mozAudioChannelType property Not supported Not supported Not supported Not supported Not supported
    mozChannels, mozFrameBufferLength, mozSampleRate properties Not supported 4.0 (2.0) Not supported Not supported Not supported
    mozGetMetadata() Not supported 17.0 (17.0) Not supported Not supported Not supported
    mozLoadFrom() Obsolete since Gecko 24 Not supported 3.6 (1.9.2) Not supported Not supported Not supported
    mozSrcObject property Not supported 18.0 (18.0) Not supported Not supported Not supported
    initialTime property ? 9.0 (9.0), removed in 23.0 (23.0) ? ? ?
    fastSeek method ? Not supported bug 778077 ? ? ?
    startDate property ? Not supported bug 847376 ? ? ?
    mediaGroup and controller properties ? Not supported bug 847377 ? ? ?
    audioTracks, and videoTracks properties ? 33.0 (33.0), behind the media.track.enabled preference. ? ? ?
    textTracks property ? On Nightly, behind the media.webvtt.enabled preference. ? ? ?
    Feature Android Firefox Mobile (Gecko) Firefox OS (Gecko) IE Mobile Opera Mobile Safari Mobile
    Basic support (Yes) (Yes) (Yes) ? (Yes) (Yes)
    buffered property (Yes) 4.0 (2.0) (Yes) ? ? ?
    defaultMuted property (Yes) 11.0 (11.0) (Yes) ? ? ?
    loop property (Yes) 11.0 (11.0) (Yes) ? ? ?
    seekable property (Yes) 8.0 (8.0) (Yes) ? ? ?
    defaultPlaybackRate property (Yes) 20.0 (20.0) (Yes) ? ? ?
    playbackRate property (Yes) 20.0 (20.0) (Yes) ? ? ?
    preservesPitch property (Yes)webkit 20.0 (20.0)moz (Yes) Not supported Not supported Not supported
    preload property (Yes) 4.0 (2.0) (Yes) ? ? ?
    played property (Yes) 15.0 (15.0) (Yes) ? ? ?
    crossOrigin property (Yes) 12.0 (12.0) as crossorigin
    22.0 (22.0)
     
    (Yes) ? ? ?
    mozAudiochannelType Not supported Not supported 1.0.1 Not supported Not supported Not supported
    mozChannels, mozFrameBufferLength, mozSampleRate properties Not supported 4.0 (2.0) (Yes) Not supported Not supported Not supported
    mozGetMetadata() Not supported 17.0 (17.0) (Yes) Not supported Not supported Not supported
    mozLoadFrom() Not supported 1.0 (1.9.2)
    Removed from 24.0 (24)
    (Yes) Not supported Not supported Not supported
    mozSrcObject property Not supported 18.0 (18.0) (Yes) Not supported Not supported Not supported
    initialTime property ? 9.0 (9.0), removed in 23.0 (23.0) (Yes) ? ? ?
    fastSeek method ? Not supported bug 778077 (Yes) ? ? ?
    startDate property ? Not supported bug 847376 (Yes) ? ? ?
    mediaGroup and controller properties ? Not supported bug 847377 (Yes) ? ? ?
    audioTracks, and videoTracks properties ? 33.0 (33.0), behind the media.track.enabled preference. (Yes) ? ? ?
    textTracks property ? On Nightly, behind the media.webvtt.enabled preference. (Yes) ? ? ?

    [1] The NETWORK_LOADED state was removed to align with the HTML spec in Gecko 2.0 (Firefox 4).

    See also

    ドキュメントのタグと貢献者

    最終更新者: Sheppy,
    サイドバーを隠す