The Sound class lets you work with sound in an application. The Sound class lets you create a Sound object, load and play an external MP3 file into that object, close the sound stream, and access data about the sound, such as information about the number of bytes in the stream and ID3 metadata. More detailed control of the sound is performed through the sound source - the SoundChannel or Microphone object for the sound - and through the properties in the SoundTransform class that control the output of the sound to the computer's speakers.
In Flash Player 10 and later and AIR 1.5 and later, you can also use
this class to work with sound that is generated dynamically. In this case,
the Sound object uses the function you assign to a sampleData
event handler to poll for sound data. The sound is played as it is
retrieved from a ByteArray object that you populate with sound data. You
can use Sound.extract() to extract sound data from a Sound
object, after which you can manipulate it before writing it back to the
stream for playback.
To control sounds that are embedded in a SWF file, use the properties in the SoundMixer class.
Note: The ActionScript 3.0 Sound API differs from ActionScript 2.0. In ActionScript 3.0, you cannot take sound objects and arrange them in a hierarchy to control their properties.
When you use this class, consider the following security model:
- Loading and playing a sound is not allowed if the calling file is in a network sandbox and the sound file to be loaded is local.
- By default, loading and playing a sound is not allowed if the calling file is local and tries to load and play a remote sound. A user must grant explicit permission to allow this type of access.
- Certain operations dealing with sound are restricted. The data in a
loaded sound cannot be accessed by a file in a different domain unless you
implement a cross-domain policy file. Sound-related APIs that fall under
this restriction are
Sound.id3,SoundMixer.computeSpectrum(),SoundMixer.bufferTime, and theSoundTransformclass.
However, in Adobe AIR, content in the application security
sandbox(content installed with the AIR application) are not restricted by
these security limitations.
For more information related to security, see the Flash Player Developer Center Topic: Security.
Events:
complete | Dispatched when data has loaded successfully. |
|---|---|
id3 | Dispatched by a Sound object when ID3 data is available for an MP3 sound. |
ioError | Dispatched when an input/output error occurs that causes a load operation to fail. |
open | Dispatched when a load operation starts. |
progress | Dispatched when data is received as a load operation progresses. |
sampleData | Dispatched when the runtime requests new audio data. |
Static methods
staticfromAudioBuffer(buffer:AudioBuffer):Sound
Creates a new Sound from an AudioBuffer immediately.
Parameters:
buffer | An AudioBuffer instance |
|---|
Returns:
A new Sound
staticfromFile(path:String):Sound
Creates a new Sound from a file path synchronously. This means that the Sound will be returned immediately (if supported).
HTML5 and Flash do not support creating Sound synchronously, so these targets
always return null.
In order to load files from a remote web address, use the loadFromFile method,
which supports asynchronous loading.
Parameters:
path | A local file path containing a sound |
|---|
Returns:
A new Sound if successful, or null if unsuccessful
staticloadFromFile(path:String):Future<Sound>
Creates a new Sound from a file path or web address asynchronously. The file load will occur in the background.
Progress, completion and error callbacks will be dispatched in the current thread using callbacks attached to a returned Future object.
Parameters:
path | A local file path or web address containing a sound |
|---|
Returns:
A Future Sound
staticloadFromFiles(paths:Array<String>):Future<Sound>
Creates a new Sound from a set of file paths or web addresses asynchronously. The audio backend will choose the first compatible file format, and will load the file it selects in the background.
Progress, completion and error callbacks will be dispatched in the current thread using callbacks attached to a returned Future object.
Parameters:
paths | A set of local file paths or web addresses containing sound |
|---|
Returns:
A Future Sound
Constructor
new(?stream:URLRequest, ?context:SoundLoaderContext)
Creates a new Sound object. If you pass a valid URLRequest object to the
Sound constructor, the constructor automatically calls the
load() function for the Sound object. If you do not pass a
valid URLRequest object to the Sound constructor, you must call the
load() function for the Sound object yourself, or the stream
will not load.
Once load() is called on a Sound object, you can't later
load a different sound file into that Sound object. To load a different
sound file, create a new Sound object.
In Flash Player 10 and later and AIR 1.5 and later, instead of using
load(), you can use the sampleData event handler
to load sound dynamically into the Sound object.
Parameters:
stream | The URL that points to an external MP3 file. |
|---|---|
context | An optional SoundLoader context object, which can define the buffer time(the minimum number of milliseconds of MP3 data to hold in the Sound object's buffer) and can specify whether the application should check for a cross-domain policy file prior to loading the sound. |
Variables
read onlybytesLoaded:Int
Returns the currently available number of bytes in this sound object. This property is usually useful only for externally loaded files.
read onlyid3:ID3Info
Provides access to the metadata that is part of an MP3 file.
MP3 sound files can contain ID3 tags, which provide metadata about the
file. If an MP3 sound that you load using the Sound.load() method
contains ID3 tags, you can query these properties. Only ID3 tags that
use the UTF-8 character set are supported.
Flash Player 9 and later and AIR support ID3 2.0 tags, specifically
2.3 and 2.4. The following tables list the standard ID3 2.0 tags and
the type of content the tags represent. The Sound.id3 property
provides access to these tags through the format my_sound.id3.COMM,
my_sound.id3.TIME, and so on. The first table describes tags that
can be accessed either through the ID3 2.0 property name or the
ActionScript property name. The second table describes ID3 tags that
are supported but do not have predefined properties in ActionScript.
| ID3 2.0 tag | Corresponding Sound class property |
|---|---|
| COMM | Sound.id3.comment |
| TALB | Sound.id3.album |
| TCON | Sound.id3.genre |
| TIT2 | Sound.id3.songName |
| TPE1 | Sound.id3.artist |
| TRCK | Sound.id3.track |
| TYER | Sound.id3.year |
The following table describes ID3 tags that are supported but do not
have predefined properties in the Sound class. You access them by
calling mySound.id3.TFLT, mySound.id3.TIME, and so on. NOTE:
None of these tags are supported in Flash Lite 4.
| Property | Description |
|---|---|
| TFLT | File type |
| TIME | Time |
| TIT1 | Content group description |
| TIT2 | Title/song name/content description |
| TIT3 | Subtitle/description refinement |
| TKEY | Initial key |
| TLAN | Languages |
| TLEN | Length |
| TMED | Media type |
| TOAL | Original album/movie/show title |
| TOFN | Original filename |
| TOLY | Original lyricists/text writers |
| TOPE | Original artists/performers |
| TORY | Original release year |
| TOWN | File owner/licensee |
| TPE1 | Lead performers/soloists |
| TPE2 | Band/orchestra/accompaniment |
| TPE3 | Conductor/performer refinement |
| TPE4 | Interpreted, remixed, or otherwise modified by |
| TPOS | Part of a set |
| TPUB | Publisher |
| TRCK | Track number/position in set |
| TRDA | Recording dates |
| TRSN | Internet radio station name |
| TRSO | Internet radio station owner |
| TSIZ | Size |
| TSRC | ISRC (international standard recording code) |
| TSSE | Software/hardware and settings used for encoding |
| TYER | Year |
| WXXX | URL link frame |
When using this property, consider the Flash Player security model:
- The
id3property of a Sound object is always permitted for SWF files that are in the same security sandbox as the sound file. For files in other sandboxes, there are security checks. - When you load the sound, using the
load()method of the Sound class, you can specify acontextparameter, which is a SoundLoaderContext object. If you set thecheckPolicyFileproperty of the SoundLoaderContext object totrue, Flash Player checks for a URL policy file on the server from which the sound is loaded. If a policy file exists and permits access from the domain of the loading SWF file, then the file is allowed to access theid3property of the Sound object; otherwise it is not.
However, in Adobe AIR, content in the application security sandbox
(content installed with the AIR application) are not restricted by
these security limitations.
For more information related to security, see the Flash Player Developer Center Topic: <a href="http://www.adobe.com/go/devnet_security_en" scope="external">Security.
read onlyisBuffering:Bool
Returns the buffering state of external MP3 files. If the value is
true, any playback is currently suspended while the object
waits for more data.
read onlyurl:String
The URL from which this sound was loaded. This property is applicable only
to Sound objects that were loaded using the Sound.load()
method. For Sound objects that are associated with a sound asset from a
SWF file's library, the value of the url property is
null.
When you first call Sound.load(), the url
property initially has a value of null, because the final URL
is not yet known. The url property will have a non-null value
as soon as an open event is dispatched from the Sound
object.
The url property contains the final, absolute URL from
which a sound was loaded. The value of url is usually the
same as the value passed to the stream parameter of
Sound.load(). However, if you passed a relative URL to
Sound.load() the value of the url property
represents the absolute URL. Additionally, if the original URL request is
redirected by an HTTP server, the value of the url property
reflects the final URL from which the sound file was actually downloaded.
This reporting of an absolute, final URL is equivalent to the behavior of
LoaderInfo.url.
In some cases, the value of the url property is truncated;
see the isURLInaccessible property for details.
Methods
close():Void
Closes the stream, causing any download of data to cease. No data may
be read from the stream after the close() method is called.
Throws:
IOError | The stream could not be closed, or the stream was not open. |
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load(stream:URLRequest, ?context:SoundLoaderContext):Void
Initiates loading of an external MP3 file from the specified URL. If you
provide a valid URLRequest object to the Sound constructor, the
constructor calls Sound.load() for you. You only need to call
Sound.load() yourself if you don't pass a valid URLRequest
object to the Sound constructor or you pass a null value.
Once load() is called on a Sound object, you can't later
load a different sound file into that Sound object. To load a different
sound file, create a new Sound object.
When using this method, consider the following security model:
- Calling
Sound.load()is not allowed if the calling file is in the local-with-file-system sandbox and the sound is in a network sandbox. - Access from the local-trusted or local-with-networking sandbox requires permission from a website through a URL policy file.
- You cannot connect to commonly reserved ports. For a complete list of blocked ports, see "Restricting Networking APIs" in the ActionScript 3.0 Developer's Guide.
- You can prevent a SWF file from using this method by setting the
allowNetworkingparameter of theobjectandembedtags in the HTML page that contains the SWF content.
In Flash Player 10 and later, if you use a multipart Content-Type(for example "multipart/form-data") that contains an upload(indicated by a "filename" parameter in a "content-disposition" header within the POST body), the POST operation is subject to the security rules applied to uploads:
- The POST operation must be performed in response to a user-initiated action, such as a mouse click or key press.
- If the POST operation is cross-domain(the POST target is not on the same server as the SWF file that is sending the POST request), the target server must provide a URL policy file that permits cross-domain access.
Also, for any multipart Content-Type, the syntax must be valid (according to the RFC2046 standards). If the syntax appears to be invalid, the POST operation is subject to the security rules applied to uploads.
In Adobe AIR, content in the application security sandbox
(content installed with the AIR application) are not restricted by these
security limitations.
For more information related to security, see the Flash Player Developer Center Topic: Security.
Parameters:
stream | A URL that points to an external MP3 file. |
|---|---|
context | An optional SoundLoader context object, which can define the buffer time(the minimum number of milliseconds of MP3 data to hold in the Sound object's buffer) and can specify whether the application should check for a cross-domain policy file prior to loading the sound. |
Throws:
IOError | A network error caused the load to fail. |
|---|---|
IOError | The |
SecurityError | Local untrusted files may not communicate with the Internet. You can work around this by reclassifying this file as local-with-networking or trusted. |
SecurityError | You cannot connect to commonly reserved ports. For a complete list of blocked ports, see "Restricting Networking APIs" in the ActionScript 3.0 Developer's Guide. |
loadCompressedDataFromByteArray(bytes:ByteArray, bytesLength:Int):Void
Load MP3 sound data from a ByteArray object into a Sound object. The data will be read from the current ByteArray position and will leave the ByteArray position at the end of the specified bytes length once finished. If the MP3 sound data contains ID3 data ID3 events will be dispatched during this function call. This function will throw an exception if the ByteArray object does not contain enough data.
Parameters:
bytes | |
|---|---|
null | bytesLength |
loadPCMFromByteArray(bytes:ByteArray, samples:Int, format:String = "float", stereo:Bool = true, sampleRate:Float = 44100):Void
Load PCM 32-bit floating point sound data from a ByteArray object into a Sound object. The data will be read from the current ByteArray position and will leave the ByteArray position at the end of the specified sample length multiplied by either 1 channel or 2 channels if the stereo flag is set once finished.
Starting with Flash Player 11.8, the amount of audio data that can be passed to this function is limited. For SWF versions >= 21, this function throws an exception if the amount of audio data passed into this function is more than 1800 seconds. That is, samples / sampleRate should be less than or equal to 1800. For swf versions < 21, the runtime fails silently if the amount of audio data passed in is more than 12000 seconds. This is provided only for backward compatibility.
This function throws an exception if the ByteArray object does not contain enough data.
Parameters:
bytes | |
|---|---|
samples | |
format | |
stereo | |
null | sampleRate |
play(startTime:Float = 0.0, loops:Int = 0, ?sndTransform:SoundTransform):SoundChannel
Generates a new SoundChannel object to play back the sound. This method returns a SoundChannel object, which you access to stop the sound and to monitor volume.(To control the volume, panning, and balance, access the SoundTransform object assigned to the sound channel.)
Parameters:
startTime | The initial position in milliseconds at which playback should start. |
|---|---|
loops | Defines the number of times a sound loops back to the
|
sndTransform | The initial SoundTransform object assigned to the sound channel. |
Returns:
A SoundChannel object, which you use to control the sound. This
method returns null if you have no sound card or if
you run out of available sound channels. The maximum number of
sound channels available at once is 32.