AudioAttributes
public
final
class
AudioAttributes
extends Object
implements
Parcelable
java.lang.Object | |
↳ | android.media.AudioAttributes |
A class to encapsulate a collection of attributes describing information about an audio stream.
AudioAttributes
supersede the notion of stream types (see for instance
AudioManager#STREAM_MUSIC
or AudioManager#STREAM_ALARM
) for defining the
behavior of audio playback. Attributes allow an application to specify more information than is
conveyed in a stream type by allowing the application to define:
- usage: "why" you are playing a sound, what is this sound used for. This is achieved with
the "usage" information. Examples of usage are
USAGE_MEDIA
andUSAGE_ALARM
. These two examples are the closest to stream types, but more detailed use cases are available. Usage information is more expressive than a stream type, and allows certain platforms or routing policies to use this information for more refined volume or routing decisions. Usage is the most important information to supply inAudioAttributes
and it is recommended to build any instance with this information supplied, seeAudioAttributes.Builder
for exceptions. - content type: "what" you are playing. The content type expresses the general category of
the content. This information is optional. But in case it is known (for instance
CONTENT_TYPE_MOVIE
for a movie streaming service orCONTENT_TYPE_MUSIC
for a music playback application) this information might be used by the audio framework to selectively configure some audio post-processing blocks. - flags: "how" is playback to be affected, see the flag definitions for the specific playback behaviors they control.
AudioAttributes
are used for example in one of the AudioTrack
constructors (see AudioTrack#AudioTrack(AudioAttributes, AudioFormat, int, int, int)
),
to configure a MediaPlayer
(see MediaPlayer#setAudioAttributes(AudioAttributes)
or a
Notification
(see Notification.audioAttributes
). An
AudioAttributes
instance is built through its builder,
AudioAttributes.Builder
.
Summary
Nested classes | |
---|---|
class |
AudioAttributes.Builder
Builder class for |
Constants | |
---|---|
int |
ALLOW_CAPTURE_BY_ALL
Indicates that the audio may be captured by any app. |
int |
ALLOW_CAPTURE_BY_NONE
Indicates that the audio is not to be recorded by any app, even if it is a system app. |
int |
ALLOW_CAPTURE_BY_SYSTEM
Indicates that the audio may only be captured by system apps. |
int |
CONTENT_TYPE_MOVIE
Content type value to use when the content type is a soundtrack, typically accompanying a movie or TV program. |
int |
CONTENT_TYPE_MUSIC
Content type value to use when the content type is music. |
int |
CONTENT_TYPE_SONIFICATION
Content type value to use when the content type is a sound used to accompany a user action, such as a beep or sound effect expressing a key click, or event, such as the type of a sound for a bonus being received in a game. |
int |
CONTENT_TYPE_SPEECH
Content type value to use when the content type is speech. |
int |
CONTENT_TYPE_UNKNOWN
Content type value to use when the content type is unknown, or other than the ones defined. |
int |
FLAG_AUDIBILITY_ENFORCED
Flag defining a behavior where the audibility of the sound will be ensured by the system. |
int |
FLAG_HW_AV_SYNC
Flag requesting the use of an output stream supporting hardware A/V synchronization. |
int |
FLAG_LOW_LATENCY
This constant was deprecated
in API level 26.
Use |
int |
SPATIALIZATION_BEHAVIOR_AUTO
Constant indicating the audio content associated with these attributes will follow the default platform behavior with regards to which content will be spatialized or not. |
int |
SPATIALIZATION_BEHAVIOR_NEVER
Constant indicating the audio content associated with these attributes should never be virtualized. |
int |
USAGE_ALARM
Usage value to use when the usage is an alarm (e.g. wake-up alarm). |
int |
USAGE_ASSISTANCE_ACCESSIBILITY
Usage value to use when the usage is for accessibility, such as with a screen reader. |
int |
USAGE_ASSISTANCE_NAVIGATION_GUIDANCE
Usage value to use when the usage is driving or navigation directions. |
int |
USAGE_ASSISTANCE_SONIFICATION
Usage value to use when the usage is sonification, such as with user interface sounds. |
int |
USAGE_ASSISTANT
Usage value to use for audio responses to user queries, audio instructions or help utterances. |
int |
USAGE_GAME
Usage value to use when the usage is for game audio. |
int |
USAGE_MEDIA
Usage value to use when the usage is media, such as music, or movie soundtracks. |
int |
USAGE_NOTIFICATION
Usage value to use when the usage is notification. |
int |
USAGE_NOTIFICATION_COMMUNICATION_DELAYED
This constant was deprecated
in API level 33.
Use |
int |
USAGE_NOTIFICATION_COMMUNICATION_INSTANT
This constant was deprecated
in API level 33.
Use |
int |
USAGE_NOTIFICATION_COMMUNICATION_REQUEST
This constant was deprecated
in API level 33.
Use |
int |
USAGE_NOTIFICATION_EVENT
Usage value to use when the usage is to attract the user's attention, such as a reminder or low battery warning. |
int |
USAGE_NOTIFICATION_RINGTONE
Usage value to use when the usage is telephony ringtone. |
int |
USAGE_UNKNOWN
Usage value to use when the usage is unknown. |
int |
USAGE_VOICE_COMMUNICATION
Usage value to use when the usage is voice communications, such as telephony or VoIP. |
int |
USAGE_VOICE_COMMUNICATION_SIGNALLING
Usage value to use when the usage is in-call signalling, such as with a "busy" beep, or DTMF tones. |
Inherited constants |
---|
Fields | |
---|---|
public
static
final
Creator<AudioAttributes> |
CREATOR
|
Public methods | |
---|---|
boolean
|
areHapticChannelsMuted()
Return if haptic channels are muted. |
int
|
describeContents()
Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. |
boolean
|
equals(Object o)
Indicates whether some other object is "equal to" this one. |
int
|
getAllowedCapturePolicy()
Return the capture policy. |
int
|
getContentType()
Return the content type. |
int
|
getFlags()
Return the flags. |
int
|
getSpatializationBehavior()
Return the behavior affecting whether spatialization will be used. |
int
|
getUsage()
Return the usage. |
int
|
getVolumeControlStream()
Returns the stream type matching this |
int
|
hashCode()
Returns a hash code value for the object. |
boolean
|
isContentSpatialized()
Return true if the audio content associated with these attributes has already been spatialized, that is it has already been processed to offer a binaural or transaural immersive audio experience. |
String
|
toString()
Returns a string representation of the object. |
void
|
writeToParcel(Parcel dest, int flags)
Flatten this object in to a Parcel. |
Inherited methods | |
---|---|
Constants
ALLOW_CAPTURE_BY_ALL
public static final int ALLOW_CAPTURE_BY_ALL
Indicates that the audio may be captured by any app.
For privacy, the following usages cannot be recorded: VOICE_COMMUNICATION*,
USAGE_NOTIFICATION*, USAGE_ASSISTANCE* and USAGE_ASSISTANT.
On Build.VERSION_CODES.Q
, this means only USAGE_UNKNOWN
,
USAGE_MEDIA
and USAGE_GAME
may be captured.
See MediaProjection
and
Builder#setAllowedCapturePolicy
.
Constant Value: 1 (0x00000001)
ALLOW_CAPTURE_BY_NONE
public static final int ALLOW_CAPTURE_BY_NONE
Indicates that the audio is not to be recorded by any app, even if it is a system app.
It is encouraged to use ALLOW_CAPTURE_BY_SYSTEM
instead of this value as system apps
provide significant and useful features for the user (such as live captioning
and accessibility).
See Builder#setAllowedCapturePolicy
.
Constant Value: 3 (0x00000003)
ALLOW_CAPTURE_BY_SYSTEM
public static final int ALLOW_CAPTURE_BY_SYSTEM
Indicates that the audio may only be captured by system apps.
System apps can capture for many purposes like accessibility, live captions, user guidance...
but abide to the following restrictions:
- the audio cannot leave the device
- the audio cannot be passed to a third party app
- the audio cannot be recorded at a higher quality than 16kHz 16bit mono
See Builder#setAllowedCapturePolicy
.
Constant Value: 2 (0x00000002)
CONTENT_TYPE_MOVIE
public static final int CONTENT_TYPE_MOVIE
Content type value to use when the content type is a soundtrack, typically accompanying a movie or TV program.
Constant Value: 3 (0x00000003)
CONTENT_TYPE_MUSIC
public static final int CONTENT_TYPE_MUSIC
Content type value to use when the content type is music.
Constant Value: 2 (0x00000002)
CONTENT_TYPE_SONIFICATION
public static final int CONTENT_TYPE_SONIFICATION
Content type value to use when the content type is a sound used to accompany a user action, such as a beep or sound effect expressing a key click, or event, such as the type of a sound for a bonus being received in a game. These sounds are mostly synthesized or short Foley sounds.
Constant Value: 4 (0x00000004)
CONTENT_TYPE_SPEECH
public static final int CONTENT_TYPE_SPEECH
Content type value to use when the content type is speech.
Constant Value: 1 (0x00000001)
CONTENT_TYPE_UNKNOWN
public static final int CONTENT_TYPE_UNKNOWN
Content type value to use when the content type is unknown, or other than the ones defined.
Constant Value: 0 (0x00000000)
FLAG_AUDIBILITY_ENFORCED
public static final int FLAG_AUDIBILITY_ENFORCED
Flag defining a behavior where the audibility of the sound will be ensured by the system. To ensure sound audibility, the system only uses built-in speakers or wired headphones and specifically excludes wireless audio devices.
Note this flag should only be used for sounds subject to regulatory behaviors in some countries, such as for camera shutter sound, and not for routing behaviors.
Constant Value: 1 (0x00000001)
FLAG_HW_AV_SYNC
public static final int FLAG_HW_AV_SYNC
Flag requesting the use of an output stream supporting hardware A/V synchronization.
Constant Value: 16 (0x00000010)
FLAG_LOW_LATENCY
public static final int FLAG_LOW_LATENCY
This constant was deprecated
in API level 26.
Use AudioTrack.Builder#setPerformanceMode(int)
with
AudioTrack#PERFORMANCE_MODE_LOW_LATENCY
to control performance.
Flag requesting a low latency path when creating an AudioTrack.
When using this flag, the sample rate must match the native sample rate
of the device. Effects processing is also unavailable.
Note that if this flag is used without specifying a bufferSizeInBytes then the
AudioTrack's actual buffer size may be too small. It is recommended that a fairly
large buffer should be specified when the AudioTrack is created.
Then the actual size can be reduced by calling
AudioTrack#setBufferSizeInFrames(int)
. The buffer size can be optimized
by lowering it after each write() call until the audio glitches, which is detected by calling
AudioTrack#getUnderrunCount()
. Then the buffer size can be increased
until there are no glitches.
This tuning step should be done while playing silence.
This technique provides a compromise between latency and glitch rate.
Constant Value: 256 (0x00000100)
SPATIALIZATION_BEHAVIOR_AUTO
public static final int SPATIALIZATION_BEHAVIOR_AUTO
Constant indicating the audio content associated with these attributes will follow the default platform behavior with regards to which content will be spatialized or not.
See also:
Constant Value: 0 (0x00000000)
SPATIALIZATION_BEHAVIOR_NEVER
public static final int SPATIALIZATION_BEHAVIOR_NEVER
Constant indicating the audio content associated with these attributes should never be virtualized.
See also:
Constant Value: 1 (0x00000001)
USAGE_ALARM
public static final int USAGE_ALARM
Usage value to use when the usage is an alarm (e.g. wake-up alarm).
Constant Value: 4 (0x00000004)
USAGE_ASSISTANCE_ACCESSIBILITY
public static final int USAGE_ASSISTANCE_ACCESSIBILITY
Usage value to use when the usage is for accessibility, such as with a screen reader.
Constant Value: 11 (0x0000000b)
USAGE_ASSISTANCE_NAVIGATION_GUIDANCE
public static final int USAGE_ASSISTANCE_NAVIGATION_GUIDANCE
Usage value to use when the usage is driving or navigation directions.
Constant Value: 12 (0x0000000c)
USAGE_ASSISTANCE_SONIFICATION
public static final int USAGE_ASSISTANCE_SONIFICATION
Usage value to use when the usage is sonification, such as with user interface sounds.
Constant Value: 13 (0x0000000d)
USAGE_ASSISTANT
public static final int USAGE_ASSISTANT
Usage value to use for audio responses to user queries, audio instructions or help utterances.
Constant Value: 16 (0x00000010)
USAGE_GAME
public static final int USAGE_GAME
Usage value to use when the usage is for game audio.
Constant Value: 14 (0x0000000e)
USAGE_MEDIA
public static final int USAGE_MEDIA
Usage value to use when the usage is media, such as music, or movie soundtracks.
Constant Value: 1 (0x00000001)
USAGE_NOTIFICATION
public static final int USAGE_NOTIFICATION
Usage value to use when the usage is notification. See other notification usages for more specialized uses.
Constant Value: 5 (0x00000005)
USAGE_NOTIFICATION_COMMUNICATION_DELAYED
public static final int USAGE_NOTIFICATION_COMMUNICATION_DELAYED
This constant was deprecated
in API level 33.
Use USAGE_NOTIFICATION
which is handled
the same way as this usage by the audio framework
Usage value to use when the usage is notification for a non-immediate type of communication such as e-mail.
Constant Value: 9 (0x00000009)
USAGE_NOTIFICATION_COMMUNICATION_INSTANT
public static final int USAGE_NOTIFICATION_COMMUNICATION_INSTANT
This constant was deprecated
in API level 33.
Use USAGE_NOTIFICATION
which is handled
the same way as this usage by the audio framework
Usage value to use when the usage is notification for an "instant" communication such as a chat, or SMS.
Constant Value: 8 (0x00000008)
USAGE_NOTIFICATION_COMMUNICATION_REQUEST
public static final int USAGE_NOTIFICATION_COMMUNICATION_REQUEST
This constant was deprecated
in API level 33.
Use USAGE_NOTIFICATION
which is handled
the same way as this usage by the audio framework
Usage value to use when the usage is a request to enter/end a communication, such as a VoIP communication or video-conference.
Constant Value: 7 (0x00000007)
USAGE_NOTIFICATION_EVENT
public static final int USAGE_NOTIFICATION_EVENT
Usage value to use when the usage is to attract the user's attention, such as a reminder or low battery warning.
Constant Value: 10 (0x0000000a)
USAGE_NOTIFICATION_RINGTONE
public static final int USAGE_NOTIFICATION_RINGTONE
Usage value to use when the usage is telephony ringtone.
Constant Value: 6 (0x00000006)
USAGE_UNKNOWN
public static final int USAGE_UNKNOWN
Usage value to use when the usage is unknown.
Constant Value: 0 (0x00000000)
USAGE_VOICE_COMMUNICATION
public static final int USAGE_VOICE_COMMUNICATION
Usage value to use when the usage is voice communications, such as telephony or VoIP.
Constant Value: 2 (0x00000002)
USAGE_VOICE_COMMUNICATION_SIGNALLING
public static final int USAGE_VOICE_COMMUNICATION_SIGNALLING
Usage value to use when the usage is in-call signalling, such as with a "busy" beep, or DTMF tones.
Constant Value: 3 (0x00000003)
Fields
Public methods
areHapticChannelsMuted
public boolean areHapticChannelsMuted ()
Return if haptic channels are muted.
Returns | |
---|---|
boolean |
true if haptic channels are muted, false otherwise. |
describeContents
public int describeContents ()
Describe the kinds of special objects contained in this Parcelable
instance's marshaled representation. For example, if the object will
include a file descriptor in the output of writeToParcel(android.os.Parcel, int)
,
the return value of this method must include the
CONTENTS_FILE_DESCRIPTOR
bit.
Returns | |
---|---|
int |
a bitmask indicating the set of special object types marshaled
by this Parcelable object instance.
Value is either 0 or CONTENTS_FILE_DESCRIPTOR |
equals
public boolean equals (Object o)
Indicates whether some other object is "equal to" this one.
The equals
method implements an equivalence relation
on non-null object references:
- It is reflexive: for any non-null reference value
x
,x.equals(x)
should returntrue
. - It is symmetric: for any non-null reference values
x
andy
,x.equals(y)
should returntrue
if and only ify.equals(x)
returnstrue
. - It is transitive: for any non-null reference values
x
,y
, andz
, ifx.equals(y)
returnstrue
andy.equals(z)
returnstrue
, thenx.equals(z)
should returntrue
. - It is consistent: for any non-null reference values
x
andy
, multiple invocations ofx.equals(y)
consistently returntrue
or consistently returnfalse
, provided no information used inequals
comparisons on the objects is modified. - For any non-null reference value
x
,x.equals(null)
should returnfalse
.
An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.
Parameters | |
---|---|
o |
Object : the reference object with which to compare. |
Returns | |
---|---|
boolean |
true if this object is the same as the obj
argument; false otherwise. |
getAllowedCapturePolicy
public int getAllowedCapturePolicy ()
Return the capture policy.
Returns | |
---|---|
int |
the capture policy set by Builder#setAllowedCapturePolicy(int) or
the default if it was not called.
Value is ALLOW_CAPTURE_BY_ALL , ALLOW_CAPTURE_BY_SYSTEM , or ALLOW_CAPTURE_BY_NONE |
getContentType
public int getContentType ()
Return the content type.
Returns | |
---|---|
int |
one of the values that can be set in Builder#setContentType(int) |
getFlags
public int getFlags ()
Return the flags.
Returns | |
---|---|
int |
a combined mask of all flags |
getSpatializationBehavior
public int getSpatializationBehavior ()
Return the behavior affecting whether spatialization will be used.
Returns | |
---|---|
int |
the spatialization behavior
Value is SPATIALIZATION_BEHAVIOR_AUTO , or SPATIALIZATION_BEHAVIOR_NEVER |
getUsage
public int getUsage ()
Return the usage.
Returns | |
---|---|
int |
one of the values that can be set in Builder#setUsage(int) |
getVolumeControlStream
public int getVolumeControlStream ()
Returns the stream type matching this AudioAttributes
instance for volume control.
Use this method to derive the stream type needed to configure the volume
control slider in an Activity
with
Activity.setVolumeControlStream(int)
for playback conducted with these
attributes.
Do not use this method to set the stream type on an audio player object
(e.g. AudioTrack
, MediaPlayer
) as this is deprecated,
use AudioAttributes
instead.
Returns | |
---|---|
int |
a valid stream type for Activity or stream volume control that matches
the attributes, or AudioManager#USE_DEFAULT_STREAM_TYPE if there isn't a direct
match. Note that USE_DEFAULT_STREAM_TYPE is not a valid value
for AudioManager#setStreamVolume(int, int, int) . |
hashCode
public int hashCode ()
Returns a hash code value for the object. This method is
supported for the benefit of hash tables such as those provided by
HashMap
.
The general contract of hashCode
is:
- Whenever it is invoked on the same object more than once during
an execution of a Java application, the
hashCode
method must consistently return the same integer, provided no information used inequals
comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. - If two objects are equal according to the
equals
method, then calling thehashCode
method on each of the two objects must produce the same integer result. - It is not required that if two objects are unequal
according to the
equals
method, then calling thehashCode
method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
Returns | |
---|---|
int |
a hash code value for this object. |
isContentSpatialized
public boolean isContentSpatialized ()
Return true if the audio content associated with these attributes has already been spatialized, that is it has already been processed to offer a binaural or transaural immersive audio experience.
Returns | |
---|---|
boolean |
true if the content has been processed |
toString
public String toString ()
Returns a string representation of the object.
Returns | |
---|---|
String |
a string representation of the object. |
writeToParcel
public void writeToParcel (Parcel dest, int flags)
Flatten this object in to a Parcel.
Parameters | |
---|---|
dest |
Parcel : The Parcel in which the object should be written.
This value cannot be null . |
flags |
int : Additional flags about how the object should be written.
May be 0 or Parcelable.PARCELABLE_WRITE_RETURN_VALUE .
Value is either 0 or a combination of Parcelable.PARCELABLE_WRITE_RETURN_VALUE , and android.os.Parcelable.PARCELABLE_ELIDE_DUPLICATES |