AudioTrack

Kotlin |Java

open class AudioTrack : AudioRouting, VolumeAutomation

kotlin.Any
↳	android.media.AudioTrack

The AudioTrack class manages and plays a single audio resource for Java applications. It allows streaming of PCM audio buffers to the audio sink for playback. This is achieved by "pushing" the data to the AudioTrack object using one of the write(byte[],int,int), write(short[],int,int), and write(float[],int,int,int) methods.

An AudioTrack instance can operate under two modes: static or streaming.
In Streaming mode, the application writes a continuous stream of data to the AudioTrack, using one of the write() methods. These are blocking and return when the data has been transferred from the Java layer to the native layer and queued for playback. The streaming mode is most useful when playing blocks of audio data that for instance are:

too big to fit in memory because of the duration of the sound to play,
too big to fit in memory because of the characteristics of the audio data (high sampling rate, bits per sample ...)
received or generated while previously queued audio is playing.

The static mode should be chosen when dealing with short sounds that fit in memory and that need to be played with the smallest latency possible. The static mode will therefore be preferred for UI and game sounds that are played often, and with the smallest overhead possible.

Upon creation, an AudioTrack object initializes its associated audio buffer. The size of this buffer, specified during the construction, determines how long an AudioTrack can play before running out of data.
For an AudioTrack using the static mode, this size is the maximum size of the sound that can be played from it.
For the streaming mode, data will be written to the audio sink in chunks of sizes less than or equal to the total buffer size. AudioTrack is not final and thus permits subclasses, but such use is not recommended.

Summary

Nested classes
open	`Builder` Builder class for `AudioTrack` objects.
	`MetricsConstants`
abstract	`OnCodecFormatChangedListener` Interface definition for a listener for codec format changes.
abstract	`OnPlaybackPositionUpdateListener` Interface definition for a callback to be invoked when the playback head position of an AudioTrack has reached a notification marker or has increased by a certain period.
abstract	`OnRoutingChangedListener` Defines the interface by which applications can receive notifications of routing changes for the associated `AudioTrack`.
abstract	`StreamEventCallback` Abstract class to receive event notifications about the stream playback in offloaded mode.

Constants
static Int	`DUAL_MONO_MODE_LL` This mode indicates that a stereo stream should be presented with the left audio channel replicated into the right audio channel.
static Int	`DUAL_MONO_MODE_LR` This mode indicates that a stereo stream should be presented with the left and right audio channels blended together and delivered to both channels.
static Int	`DUAL_MONO_MODE_OFF` This mode disables any Dual Mono presentation effect.
static Int	`DUAL_MONO_MODE_RR` This mode indicates that a stereo stream should be presented with the right audio channel replicated into the left audio channel.
static Int	`ENCAPSULATION_METADATA_TYPE_DVB_AD_DESCRIPTOR` Encapsulation metadata type for DVB AD descriptor.
static Int	`ENCAPSULATION_METADATA_TYPE_FRAMEWORK_TUNER` Encapsulation metadata type for framework tuner information.
static Int	`ENCAPSULATION_METADATA_TYPE_SUPPLEMENTARY_AUDIO_PLACEMENT` Encapsulation metadata type for placement of supplementary audio.
static Int	`ENCAPSULATION_MODE_ELEMENTARY_STREAM` This mode indicates metadata encapsulation with an elementary stream payload.
static Int	`ENCAPSULATION_MODE_NONE` This mode indicates no metadata encapsulation, which is the default mode for sending audio data through `AudioTrack`.
static Int	`ERROR` Denotes a generic operation failure.
static Int	`ERROR_BAD_VALUE` Denotes a failure due to the use of an invalid value.
static Int	`ERROR_DEAD_OBJECT` An error code indicating that the object reporting it is no longer valid and needs to be recreated.
static Int	`ERROR_INVALID_OPERATION` Denotes a failure due to the improper use of a method.
static Int	`MODE_STATIC` Creation mode where audio data is transferred from Java to the native layer only once before the audio starts playing.
static Int	`MODE_STREAM` Creation mode where audio data is streamed from Java to the native layer as the audio is playing.
static Int	`PERFORMANCE_MODE_LOW_LATENCY` Low latency performance mode for an `AudioTrack`.
static Int	`PERFORMANCE_MODE_NONE` Default performance mode for an `AudioTrack`.
static Int	`PERFORMANCE_MODE_POWER_SAVING` Power saving performance mode for an `AudioTrack`.
static Int	`PLAYSTATE_PAUSED` indicates AudioTrack state is paused
static Int	`PLAYSTATE_PLAYING` indicates AudioTrack state is playing
static Int	`PLAYSTATE_STOPPED` indicates AudioTrack state is stopped
static Int	`STATE_INITIALIZED` State of an AudioTrack that is ready to be used.
static Int	`STATE_NO_STATIC_DATA` State of a successfully initialized AudioTrack that uses static data, but that hasn't received that data yet.
static Int	`STATE_UNINITIALIZED` State of an AudioTrack that was not successfully initialized upon creation.
static Int	`SUCCESS` Denotes a successful operation.
static Int	`SUPPLEMENTARY_AUDIO_PLACEMENT_LEFT` Supplementary audio placement left.
static Int	`SUPPLEMENTARY_AUDIO_PLACEMENT_NORMAL` Supplementary audio placement normal.
static Int	`SUPPLEMENTARY_AUDIO_PLACEMENT_RIGHT` Supplementary audio placement right.
static Int	`WRITE_BLOCKING` The write mode indicating the write operation will block until all data has been written, to be used as the actual value of the writeMode parameter in `write(byte[],int,int,int)`, `write(short[],int,int,int)`, `write(float[],int,int,int)`, `write(java.nio.ByteBuffer,int,int)`, and `write(java.nio.ByteBuffer,int,int,long)`.
static Int	`WRITE_NON_BLOCKING` The write mode indicating the write operation will return immediately after queuing as much audio data for playback as possible without blocking, to be used as the actual value of the writeMode parameter in `write(java.nio.ByteBuffer,int,int)`, `write(short[],int,int,int)`, `write(float[],int,int,int)`, `write(java.nio.ByteBuffer,int,int)`, and `write(java.nio.ByteBuffer,int,int,long)`.

Public constructors
`AudioTrack(attributes: AudioAttributes!, format: AudioFormat!, bufferSizeInBytes: Int, mode: Int, sessionId: Int)` Class constructor with `AudioAttributes` and `AudioFormat`.
`AudioTrack(streamType: Int, sampleRateInHz: Int, channelConfig: Int, audioFormat: Int, bufferSizeInBytes: Int, mode: Int)` Class constructor.
`AudioTrack(streamType: Int, sampleRateInHz: Int, channelConfig: Int, audioFormat: Int, bufferSizeInBytes: Int, mode: Int, sessionId: Int)` Class constructor with audio session.

Public methods
open Unit	`addOnCodecFormatChangedListener(executor: Executor, listener: AudioTrack.OnCodecFormatChangedListener)` Adds an `OnCodecFormatChangedListener` to receive notifications of codec format change events on this `AudioTrack`.
open Unit	`addOnRoutingChangedListener(listener: AudioRouting.OnRoutingChangedListener!, handler: Handler!)` Adds an `AudioRouting.OnRoutingChangedListener` to receive notifications of routing changes on this AudioTrack.
open Unit	`addOnRoutingChangedListener(listener: AudioTrack.OnRoutingChangedListener!, handler: Handler!)` Adds an `OnRoutingChangedListener` to receive notifications of routing changes on this AudioTrack.
open Int	`attachAuxEffect(effectId: Int)` Attaches an auxiliary effect to the audio track.
open VolumeShaper	`createVolumeShaper(configuration: VolumeShaper.Configuration)` Returns a `VolumeShaper` object that can be used modify the volume envelope of the player or track.
open Unit	`flush()` Flushes the audio data currently queued for playback.
open AudioAttributes	`getAudioAttributes()` Returns the `AudioAttributes` used in configuration.
open Float	`getAudioDescriptionMixLeveldB()` Returns the Audio Description mix level in dB.
open Int	`getAudioFormat()` Returns the configured audio data encoding.
open Int	`getAudioSessionId()` Returns the audio session ID.
open Int	`getBufferCapacityInFrames()` Returns the maximum size of the `AudioTrack` buffer in frames.
open Int	`getBufferSizeInFrames()` Returns the effective size of the `AudioTrack` buffer that the application writes to.
open Int	`getChannelConfiguration()` Returns the configured channel position mask.
open Int	`getChannelCount()` Returns the configured number of channels.
open Int	`getDualMonoMode()` Returns the Dual Mono mode presentation setting.
open AudioFormat	`getFormat()` Returns the configured `AudioTrack` format.
open LogSessionId	`getLogSessionId()` Returns the `LogSessionId`.
open static Float	`getMaxVolume()` Returns the maximum gain value, which is greater than or equal to 1.
open PersistableBundle!	`getMetrics()` Return Metrics data about the current AudioTrack instance.
open static Int	`getMinBufferSize(sampleRateInHz: Int, channelConfig: Int, audioFormat: Int)` Returns the estimated minimum buffer size required for an AudioTrack object to be created in the `MODE_STREAM` mode.
open static Float	`getMinVolume()` Returns the minimum gain value, which is the constant 0.
open static Int	`getNativeOutputSampleRate(streamType: Int)` Returns the output sample rate in Hz for the specified stream type.
open Int	`getNotificationMarkerPosition()` Returns marker position expressed in frames.
open Int	`getOffloadDelay()` Return the decoder delay of an offloaded track, expressed in frames, previously set with `setOffloadDelayPadding(int,int)`, or 0 if it was never modified.
open Int	`getOffloadPadding()` Return the decoder padding of an offloaded track, expressed in frames, previously set with `setOffloadDelayPadding(int,int)`, or 0 if it was never modified.
open Int	`getPerformanceMode()` Returns the current performance mode of the `AudioTrack`.
open Int	`getPlayState()` Returns the playback state of the AudioTrack instance.
open Int	`getPlaybackHeadPosition()` Returns the playback head position expressed in frames.
open PlaybackParams	`getPlaybackParams()` Returns the current playback parameters.
open Int	`getPlaybackRate()` Returns the current playback sample rate rate in Hz.
open Int	`getPositionNotificationPeriod()` Returns the notification update period expressed in frames.
open AudioDeviceInfo!	`getPreferredDevice()` Returns the selected output specified by `setPreferredDevice`.
open AudioDeviceInfo!	`getRoutedDevice()` Returns an `AudioDeviceInfo` identifying the current routing of this AudioTrack.
open Int	`getSampleRate()` Returns the configured audio source sample rate in Hz.
open Int	`getStartThresholdInFrames()` Returns the streaming start threshold of the `AudioTrack`.
open Int	`getState()` Returns the state of the AudioTrack instance.
open Int	`getStreamType()` Returns the volume stream type of this AudioTrack.
open Boolean	`getTimestamp(timestamp: AudioTimestamp!)` Poll for a timestamp on demand.
open Int	`getUnderrunCount()` Returns the number of underrun occurrences in the application-level write buffer since the AudioTrack was created.
open static Boolean	`isDirectPlaybackSupported(format: AudioFormat, attributes: AudioAttributes)` Returns whether direct playback of an audio format with the provided attributes is currently supported on the system.
open Boolean	`isOffloadedPlayback()` Returns whether the track was built with `Builder.setOffloadedPlayback(boolean)` set to `true`.
open Unit	`pause()` Pauses the playback of the audio data.
open Unit	`play()` Starts playing an AudioTrack.
open Unit	`registerStreamEventCallback(executor: Executor, eventCallback: AudioTrack.StreamEventCallback)` Registers a callback for the notification of stream events.
open Unit	`release()` Releases the native AudioTrack resources.
open Int	`reloadStaticData()` Sets the playback head position within the static buffer to zero, that is it rewinds to start of static buffer.
open Unit	`removeOnCodecFormatChangedListener(listener: AudioTrack.OnCodecFormatChangedListener)` Removes an `OnCodecFormatChangedListener` which has been previously added to receive codec format change events.
open Unit	`removeOnRoutingChangedListener(listener: AudioRouting.OnRoutingChangedListener!)` Removes an `AudioRouting.OnRoutingChangedListener` which has been previously added to receive rerouting notifications.
open Unit	`removeOnRoutingChangedListener(listener: AudioTrack.OnRoutingChangedListener!)` Removes an `OnRoutingChangedListener` which has been previously added to receive rerouting notifications.
open Boolean	`setAudioDescriptionMixLeveldB(level: Float)` Sets the Audio Description mix level in dB.
open Int	`setAuxEffectSendLevel(level: Float)` Sets the send level of the audio track to the attached auxiliary effect `attachAuxEffect(int)`.
open Int	`setBufferSizeInFrames(bufferSizeInFrames: Int)` Limits the effective size of the `AudioTrack` buffer that the application writes to.
open Boolean	`setDualMonoMode(dualMonoMode: Int)` Sets the Dual Mono mode presentation on the output device.
open Unit	`setLogSessionId(logSessionId: LogSessionId)` Sets a `LogSessionId` instance to this AudioTrack for metrics collection.
open Int	`setLoopPoints(startInFrames: Int, endInFrames: Int, loopCount: Int)` Sets the loop points and the loop count.
open Int	`setNotificationMarkerPosition(markerInFrames: Int)` Sets the position of the notification marker.
open Unit	`setOffloadDelayPadding(delayInFrames: Int, paddingInFrames: Int)` Configures the delay and padding values for the current compressed stream playing in offload mode.
open Unit	`setOffloadEndOfStream()` Declares that the last write() operation on this track provided the last buffer of this stream.
open Int	`setPlaybackHeadPosition(positionInFrames: Int)` Sets the playback head position within the static buffer.
open Unit	`setPlaybackParams(params: PlaybackParams)` Sets the playback parameters.
open Unit	`setPlaybackPositionUpdateListener(listener: AudioTrack.OnPlaybackPositionUpdateListener!)` Sets the listener the AudioTrack notifies when a previously set marker is reached or for each periodic playback head position update.
open Unit	`setPlaybackPositionUpdateListener(listener: AudioTrack.OnPlaybackPositionUpdateListener!, handler: Handler!)` Sets the listener the AudioTrack notifies when a previously set marker is reached or for each periodic playback head position update.
open Int	`setPlaybackRate(sampleRateInHz: Int)` Sets the playback sample rate for this track.
open Int	`setPositionNotificationPeriod(periodInFrames: Int)` Sets the period for the periodic notification event.
open Boolean	`setPreferredDevice(deviceInfo: AudioDeviceInfo!)` Specifies an audio device (via an `AudioDeviceInfo` object) to route the output from this AudioTrack.
open Int	`setPresentation(presentation: AudioPresentation)` Sets the audio presentation.
open Int	`setStartThresholdInFrames(startThresholdInFrames: Int)` Sets the streaming start threshold for an `AudioTrack`.
open Int	`setStereoVolume(leftGain: Float, rightGain: Float)` Sets the specified left and right output gain values on the AudioTrack.
open Int	`setVolume(gain: Float)` Sets the specified output gain value on all channels of this track.
open Unit	`stop()` Stops playing the audio data.
open Unit	`unregisterStreamEventCallback(eventCallback: AudioTrack.StreamEventCallback)` Unregisters the callback for notification of stream events, previously registered with `registerStreamEventCallback(java.util.concurrent.Executor,android.media.AudioTrack.StreamEventCallback)`.
open Int	`write(audioData: ByteArray, offsetInBytes: Int, sizeInBytes: Int)` Writes the audio data to the audio sink for playback (streaming mode), or copies audio data for later playback (static buffer mode).
open Int	`write(audioData: ByteArray, offsetInBytes: Int, sizeInBytes: Int, writeMode: Int)` Writes the audio data to the audio sink for playback (streaming mode), or copies audio data for later playback (static buffer mode).
open Int	`write(audioData: FloatArray, offsetInFloats: Int, sizeInFloats: Int, writeMode: Int)` Writes the audio data to the audio sink for playback (streaming mode), or copies audio data for later playback (static buffer mode).
open Int	`write(audioData: ByteBuffer, sizeInBytes: Int, writeMode: Int)` Writes the audio data to the audio sink for playback (streaming mode), or copies audio data for later playback (static buffer mode).
open Int	`write(audioData: ByteBuffer, sizeInBytes: Int, writeMode: Int, timestamp: Long)` Writes the audio data to the audio sink for playback in streaming mode on a HW_AV_SYNC track.
open Int	`write(audioData: ShortArray, offsetInShorts: Int, sizeInShorts: Int)` Writes the audio data to the audio sink for playback (streaming mode), or copies audio data for later playback (static buffer mode).
open Int	`write(audioData: ShortArray, offsetInShorts: Int, sizeInShorts: Int, writeMode: Int)` Writes the audio data to the audio sink for playback (streaming mode), or copies audio data for later playback (static buffer mode).

Protected methods
open Unit	`finalize()`
open Int	`getNativeFrameCount()` Returns the frame count of the native `AudioTrack` buffer.
open Unit	`setState(state: Int)` Sets the initialization state of the instance.

Constants

DUAL_MONO_MODE_LL

Added in API level 30

static val DUAL_MONO_MODE_LL: Int

This mode indicates that a stereo stream should be presented with the left audio channel replicated into the right audio channel. Behavior for non-stereo streams is implementation defined. A suggested guideline is that all channels with left-right stereo symmetry will have the left channel position replicated into the right channel position. The center channels (with no left/right symmetry) or unbalanced channels are left alone. The Dual Mono effect occurs before volume scaling.

Value: 2

DUAL_MONO_MODE_LR

Added in API level 30

static val DUAL_MONO_MODE_LR: Int

This mode indicates that a stereo stream should be presented with the left and right audio channels blended together and delivered to both channels. Behavior for non-stereo streams is implementation defined. A suggested guideline is that the left-right stereo symmetric channels are pairwise blended; the other channels such as center are left alone. The Dual Mono effect occurs before volume scaling.

Value: 1

DUAL_MONO_MODE_OFF

Added in API level 30

static val DUAL_MONO_MODE_OFF: Int

This mode disables any Dual Mono presentation effect.

Value: 0

DUAL_MONO_MODE_RR

Added in API level 30

static val DUAL_MONO_MODE_RR: Int

This mode indicates that a stereo stream should be presented with the right audio channel replicated into the left audio channel. Behavior for non-stereo streams is implementation defined. A suggested guideline is that all channels with left-right stereo symmetry will have the right channel position replicated into the left channel position. The center channels (with no left/right symmetry) or unbalanced channels are left alone. The Dual Mono effect occurs before volume scaling.

Value: 3

ENCAPSULATION_METADATA_TYPE_DVB_AD_DESCRIPTOR

Added in API level 30

static val ENCAPSULATION_METADATA_TYPE_DVB_AD_DESCRIPTOR: Int

Encapsulation metadata type for DVB AD descriptor. This metadata is formatted per ETSI TS 101 154 Table E.1: AD_descriptor.

Value: 2

ENCAPSULATION_METADATA_TYPE_FRAMEWORK_TUNER

Added in API level 30

static val ENCAPSULATION_METADATA_TYPE_FRAMEWORK_TUNER: Int

Encapsulation metadata type for framework tuner information. Refer to the Android Media TV Tuner API for details.

Value: 1

ENCAPSULATION_METADATA_TYPE_SUPPLEMENTARY_AUDIO_PLACEMENT

Added in API level 34

static val ENCAPSULATION_METADATA_TYPE_SUPPLEMENTARY_AUDIO_PLACEMENT: Int

Encapsulation metadata type for placement of supplementary audio. A 32 bit integer constant, one of SUPPLEMENTARY_AUDIO_PLACEMENT_NORMAL, SUPPLEMENTARY_AUDIO_PLACEMENT_LEFT, SUPPLEMENTARY_AUDIO_PLACEMENT_RIGHT.

Value: 3

ENCAPSULATION_MODE_ELEMENTARY_STREAM

Added in API level 30

static val ENCAPSULATION_MODE_ELEMENTARY_STREAM: Int

This mode indicates metadata encapsulation with an elementary stream payload. Both compressed and PCM format is allowed.

Value: 1

ENCAPSULATION_MODE_NONE

Added in API level 30

static val ENCAPSULATION_MODE_NONE: Int

This mode indicates no metadata encapsulation, which is the default mode for sending audio data through AudioTrack.

Value: 0

Parameters
`attributes`	AudioAttributes!: a non-null `AudioAttributes` instance.
`format`	AudioFormat!: a non-null `AudioFormat` instance describing the format of the data that will be played through this AudioTrack. See `AudioFormat.Builder` for configuring the audio format parameters such as encoding, channel mask and sample rate.
`bufferSizeInBytes`	Int: the total size (in bytes) of the internal buffer where audio data is read from for playback. This should be a nonzero multiple of the frame size in bytes. If the track's creation mode is `MODE_STATIC`, this is the maximum length sample, or audio clip, that can be played by this instance. If the track's creation mode is `MODE_STREAM`, this should be the desired buffer size for the `AudioTrack` to satisfy the application's latency requirements. If `bufferSizeInBytes` is less than the minimum buffer size for the output sink, it is increased to the minimum buffer size. The method `getBufferSizeInFrames()` returns the actual size in frames of the buffer created, which determines the minimum frequency to write to the streaming `AudioTrack` to avoid underrun. See `getMinBufferSize(int,int,int)` to determine the estimated minimum buffer size for an AudioTrack instance in streaming mode.
`mode`	Int: streaming or static buffer. See `MODE_STATIC` and `MODE_STREAM`.
`sessionId`	Int: ID of audio session the AudioTrack must be attached to, or `AudioManager.AUDIO_SESSION_ID_GENERATE` if the session isn't known at construction time. See also `AudioManager.generateAudioSessionId()` to obtain a session ID before construction.

Parameters
`streamType`	Int: the type of the audio stream. See `AudioManager.STREAM_VOICE_CALL`, `AudioManager.STREAM_SYSTEM`, `AudioManager.STREAM_RING`, `AudioManager.STREAM_MUSIC`, `AudioManager.STREAM_ALARM`, and `AudioManager.STREAM_NOTIFICATION`.
`sampleRateInHz`	Int: the initial source sample rate expressed in Hz. `AudioFormat.SAMPLE_RATE_UNSPECIFIED` means to use a route-dependent value which is usually the sample rate of the sink. `getSampleRate()` can be used to retrieve the actual sample rate chosen.
`channelConfig`	Int: describes the configuration of the audio channels. See `AudioFormat.CHANNEL_OUT_MONO` and `AudioFormat.CHANNEL_OUT_STEREO`
`audioFormat`	Int: the format in which the audio data is represented. See `AudioFormat.ENCODING_PCM_16BIT`, `AudioFormat.ENCODING_PCM_8BIT`, and `AudioFormat.ENCODING_PCM_FLOAT`.
`bufferSizeInBytes`	Int: the total size (in bytes) of the internal buffer where audio data is read from for playback. This should be a nonzero multiple of the frame size in bytes. If the track's creation mode is `MODE_STATIC`, this is the maximum length sample, or audio clip, that can be played by this instance. If the track's creation mode is `MODE_STREAM`, this should be the desired buffer size for the `AudioTrack` to satisfy the application's latency requirements. If `bufferSizeInBytes` is less than the minimum buffer size for the output sink, it is increased to the minimum buffer size. The method `getBufferSizeInFrames()` returns the actual size in frames of the buffer created, which determines the minimum frequency to write to the streaming `AudioTrack` to avoid underrun. See `getMinBufferSize(int,int,int)` to determine the estimated minimum buffer size for an AudioTrack instance in streaming mode.
`mode`	Int: streaming or static buffer. See `MODE_STATIC` and `MODE_STREAM`

Parameters
`executor`	Executor: Specifies the `Executor` object to control execution. This value cannot be `null`. Callback and listener events are dispatched through this `Executor`, providing an easy way to control which thread is used. To dispatch events through the main thread of your application, you can use `Context.getMainExecutor()`. Otherwise, provide an `Executor` that dispatches to an appropriate thread.
`listener`	AudioTrack.OnCodecFormatChangedListener: The `OnCodecFormatChangedListener` interface to receive notifications of codec events. This value cannot be `null`.

Parameters
`listener`	AudioRouting.OnRoutingChangedListener!: The `AudioRouting.OnRoutingChangedListener` interface to receive notifications of rerouting events.
`handler`	Handler!: Specifies the `Handler` object for the thread on which to execute the callback. If `null`, the `Handler` associated with the main `Looper` will be used.

Parameters
`listener`	AudioTrack.OnRoutingChangedListener!: The `OnRoutingChangedListener` interface to receive notifications of rerouting events.
`handler`	Handler!: Specifies the `Handler` object for the thread on which to execute the callback. If `null`, the `Handler` associated with the main `Looper` will be used.

Exceptions
`java.lang.IllegalArgumentException`	if the `configuration` is not allowed by the player.
`java.lang.IllegalStateException`	if too many `VolumeShaper`s are requested or the state of the player does not permit its creation (e.g. player is released).

Parameters
`sampleRateInHz`	Int: the source sample rate expressed in Hz. `AudioFormat.SAMPLE_RATE_UNSPECIFIED` is not permitted.
`channelConfig`	Int: describes the configuration of the audio channels. See `AudioFormat.CHANNEL_OUT_MONO` and `AudioFormat.CHANNEL_OUT_STEREO`
`audioFormat`	Int: the format in which the audio data is represented. See `AudioFormat.ENCODING_PCM_16BIT` and `AudioFormat.ENCODING_PCM_8BIT`, and `AudioFormat.ENCODING_PCM_FLOAT`.

Parameters
`format`	AudioFormat: a non-null `AudioFormat` instance describing the format of the audio data.
`attributes`	AudioAttributes: a non-null `AudioAttributes` instance.

Parameters
`executor`	Executor: `Executor` to handle the callbacks. This value cannot be `null`. Callback and listener events are dispatched through this `Executor`, providing an easy way to control which thread is used. To dispatch events through the main thread of your application, you can use `Context.getMainExecutor()`. Otherwise, provide an `Executor` that dispatches to an appropriate thread.
`eventCallback`	AudioTrack.StreamEventCallback: the callback to receive the stream event notifications. This value cannot be `null`.

Parameters
`startInFrames`	Int: loop start marker expressed in frames. Zero corresponds to start of buffer. The start marker must not be greater than or equal to the buffer size in frames, or negative. Value is 0 or greater
`endInFrames`	Int: loop end marker expressed in frames. The total buffer size in frames corresponds to end of buffer. The end marker must not be greater than the buffer size in frames. For looping, the end marker must not be less than or equal to the start marker, but to disable looping it is permitted for start marker, end marker, and loop count to all be 0. If any input parameters are out of range, this method returns `ERROR_BAD_VALUE`. If the loop period (endInFrames - startInFrames) is too small for the implementation to support, `ERROR_BAD_VALUE` is returned. The loop range is the interval [startInFrames, endInFrames). As of `android.os.Build.VERSION_CODES#M`, the position is left unchanged, unless it is greater than or equal to the loop end marker, in which case it is forced to the loop start marker. For earlier API levels, the effect on position is unspecified. Value is 0 or greater
`loopCount`	Int: the number of times the loop is looped; must be greater than or equal to -1. A value of -1 means infinite looping, and 0 disables looping. A value of positive N means to "loop" (go back) N times. For example, a value of one means to play the region two times in total. Value is -1 or greater

Parameters
`delayInFrames`	Int: number of frames to be ignored at the beginning of the stream. A value of 0 indicates no delay is to be applied. Value is 0 or greater
`paddingInFrames`	Int: number of frames to be ignored at the end of the stream. A value of 0 of 0 indicates no padding is to be applied. Value is 0 or greater

Exceptions
`java.lang.IllegalArgumentException`	if the parameters are invalid or not accepted.
`java.lang.IllegalStateException`	if track is not initialized.

Parameters
`listener`	AudioTrack.OnPlaybackPositionUpdateListener!:
`handler`	Handler!: the Handler that will receive the event notification messages.

Exceptions
`java.lang.IllegalArgumentException`	if the audio presentation is null.
`java.lang.IllegalStateException`	if track is not initialized.

Exceptions
`java.lang.IllegalStateException`	if the track is not initialized or the track transfer mode is not `MODE_STREAM`.
`java.lang.IllegalArgumentException`	if startThresholdInFrames is not positive.

Parameters
`leftGain`	Float: output gain for the left channel.
`rightGain`	Float: output gain for the right channel

Parameters
`audioData`	ByteArray: the array that holds the data to play. This value cannot be `null`.
`offsetInBytes`	Int: the offset expressed in bytes in audioData where the data to write starts. Must not be negative, or cause the data access to go out of bounds of the array.
`sizeInBytes`	Int: the number of bytes to write in audioData after the offset. Must not be negative, or cause the data access to go out of bounds of the array.

Parameters
`audioData`	FloatArray: the array that holds the data to write. The implementation does not clip for sample values within the nominal range [-1.0f, 1.0f], provided that all gains in the audio pipeline are less than or equal to unity (1.0f), and in the absence of post-processing effects that could add energy, such as reverb. For the convenience of applications that compute samples using filters with non-unity gain, sample values +3 dB beyond the nominal range are permitted. However such values may eventually be limited or clipped, depending on various gains and later processing in the audio path. Therefore applications are encouraged to provide samples values within the nominal range. This value cannot be `null`.
`offsetInFloats`	Int: the offset, expressed as a number of floats, in audioData where the data to write starts. Must not be negative, or cause the data access to go out of bounds of the array.
`sizeInFloats`	Int: the number of floats to write in audioData after the offset. Must not be negative, or cause the data access to go out of bounds of the array.
`writeMode`	Int: one of `WRITE_BLOCKING`, `WRITE_NON_BLOCKING`. It has no effect in static mode. With `WRITE_BLOCKING`, the write will block until all data has been written to the audio sink. With `WRITE_NON_BLOCKING`, the write will return immediately after queuing as much audio data for playback as possible without blocking. Value is `android.media.AudioTrack#WRITE_BLOCKING`, or `android.media.AudioTrack#WRITE_NON_BLOCKING`

Parameters
`audioData`	ByteBuffer: the buffer that holds the data to write, starting at the position reported by `audioData.position()`. Note that upon return, the buffer position (`audioData.position()`) will have been advanced to reflect the amount of data that was successfully written to the AudioTrack. This value cannot be `null`.
`sizeInBytes`	Int: number of bytes to write. It is recommended but not enforced that the number of bytes requested be a multiple of the frame size (sample size in bytes multiplied by the channel count). Note this may differ from `audioData.remaining()`, but cannot exceed it.
`writeMode`	Int: one of `WRITE_BLOCKING`, `WRITE_NON_BLOCKING`. It has no effect in static mode. With `WRITE_BLOCKING`, the write will block until all data has been written to the audio sink. With `WRITE_NON_BLOCKING`, the write will return immediately after queuing as much audio data for playback as possible without blocking. Value is `android.media.AudioTrack#WRITE_BLOCKING`, or `android.media.AudioTrack#WRITE_NON_BLOCKING`

Parameters
`audioData`	ShortArray: the array that holds the data to play. This value cannot be `null`.
`offsetInShorts`	Int: the offset expressed in shorts in audioData where the data to play starts. Must not be negative, or cause the data access to go out of bounds of the array.
`sizeInShorts`	Int: the number of shorts to read in audioData after the offset. Must not be negative, or cause the data access to go out of bounds of the array.

AudioTrack

Summary

Constants

DUAL_MONO_MODE_LL

DUAL_MONO_MODE_LR

DUAL_MONO_MODE_OFF

DUAL_MONO_MODE_RR

ENCAPSULATION_METADATA_TYPE_DVB_AD_DESCRIPTOR

ENCAPSULATION_METADATA_TYPE_FRAMEWORK_TUNER

ENCAPSULATION_METADATA_TYPE_SUPPLEMENTARY_AUDIO_PLACEMENT

ENCAPSULATION_MODE_ELEMENTARY_STREAM

ENCAPSULATION_MODE_NONE

ERROR

ERROR_BAD_VALUE

ERROR_DEAD_OBJECT

ERROR_INVALID_OPERATION

MODE_STATIC

MODE_STREAM

PERFORMANCE_MODE_LOW_LATENCY

PERFORMANCE_MODE_NONE

PERFORMANCE_MODE_POWER_SAVING

PLAYSTATE_PAUSED

PLAYSTATE_PLAYING

PLAYSTATE_STOPPED

STATE_INITIALIZED

STATE_NO_STATIC_DATA

STATE_UNINITIALIZED

SUCCESS

SUPPLEMENTARY_AUDIO_PLACEMENT_LEFT

SUPPLEMENTARY_AUDIO_PLACEMENT_NORMAL

SUPPLEMENTARY_AUDIO_PLACEMENT_RIGHT

WRITE_BLOCKING

WRITE_NON_BLOCKING

Public constructors

AudioTrack

AudioTrack

AudioTrack

Public methods

addOnCodecFormatChangedListener

addOnRoutingChangedListener

addOnRoutingChangedListener

attachAuxEffect

createVolumeShaper

flush

getAudioAttributes

getAudioDescriptionMixLeveldB

getAudioFormat

getAudioSessionId

getBufferCapacityInFrames

getBufferSizeInFrames

getChannelConfiguration

getChannelCount

getDualMonoMode

getFormat

getLogSessionId

getMaxVolume

getMetrics

getMinBufferSize

getMinVolume

getNativeOutputSampleRate

getNotificationMarkerPosition

getOffloadDelay

getOffloadPadding

getPerformanceMode

getPlayState

getPlaybackHeadPosition

getPlaybackParams

getPlaybackRate

getPositionNotificationPeriod

getPreferredDevice

getRoutedDevice

getSampleRate

getStartThresholdInFrames

getState

getStreamType

getTimestamp

getUnderrunCount

isDirectPlaybackSupported

isOffloadedPlayback

pause