SpeedChangingAudioProcessor

Kotlin |Java

@UnstableApi
public final class SpeedChangingAudioProcessor implements AudioProcessor

An AudioProcessor that changes the speed of audio samples depending on their timestamp.

Summary

Public constructors
`SpeedChangingAudioProcessor(SpeedProvider speedProvider)`

Public methods
`AudioProcessor.AudioFormat`	`configure(AudioProcessor.AudioFormat inputAudioFormat)` Configures the processor to process input audio with the specified format.
`void`	`flush()` Clears any buffered data and pending output.
`long`	`getDurationAfterProcessorApplied(long durationUs)` Returns the expected duration of the output stream when the processor is applied given a input `durationUs`.
`long`	`getMediaDurationUs(long playoutDurationUs)` Returns the input media duration for the given playout duration.
`ByteBuffer`	`getOutput()` Returns a buffer containing processed output data between its position and limit.
`static long`	`getSampleCountAfterProcessorApplied( SpeedProvider speedProvider, @IntRange(from = 1) int inputSampleRateHz, @IntRange(from = 1) long inputSamples )` Returns the estimated number of samples output given the provided parameters.
`void`	`getSpeedAdjustedTimeAsync(long inputTimeUs, TimestampConsumer callback)` Calculates the time at which the `inputTimeUs` is outputted at after the speed changes has been applied.
`boolean`	`isActive()` Returns whether the processor is configured and will process input buffers.
`boolean`	`isEnded()` Returns whether this processor will return no more output from `getOutput` until `flush` has been called and more input has been queued.
`void`	`queueEndOfStream()` Queues an end of stream signal.
`void`	`queueInput(ByteBuffer inputBuffer)` Queues audio data between the position and limit of the `inputBuffer` for processing.
`void`	`reset()` Resets the processor to its unconfigured state, releasing any resources.

Inherited Constants

From androidx.media3.common.audio.AudioProcessor

static final ByteBuffer

EMPTY_BUFFER

An empty, direct ByteBuffer.

Public constructors

SpeedChangingAudioProcessor

public SpeedChangingAudioProcessor(SpeedProvider speedProvider)

Public methods

configure

public AudioProcessor.AudioFormat configure(AudioProcessor.AudioFormat inputAudioFormat)

Configures the processor to process input audio with the specified format. After calling this method, call isActive to determine whether the audio processor is active. Returns the configured output audio format if this instance is active.

After calling this method, it is necessary to flush the processor to apply the new configuration. Before applying the new configuration, it is safe to queue input and get output in the old input/output formats. Call queueEndOfStream when no more input will be supplied in the old input format.

Parameters
`AudioProcessor.AudioFormat inputAudioFormat`	The format of audio that will be queued after the next call to `flush`.

Returns
`AudioProcessor.AudioFormat`	The configured output audio format if this instance is `active`.

Throws
`androidx.media3.common.audio.AudioProcessor.UnhandledAudioFormatException`	Thrown if the specified format can't be handled as input.

flush

public void flush()

Clears any buffered data and pending output. If the audio processor is active, also prepares the audio processor to receive a new stream of input in the last configured (pending) format.

getDurationAfterProcessorApplied

public long getDurationAfterProcessorApplied(long durationUs)

Returns the expected duration of the output stream when the processor is applied given a input durationUs.

getMediaDurationUs

public long getMediaDurationUs(long playoutDurationUs)

Returns the input media duration for the given playout duration.

Both durations are counted from the last reset or flush of the audio processor.

The playoutDurationUs must be less than last processed buffer output time.

Parameters
`long playoutDurationUs`	The playout duration in microseconds.

Returns
`long`	The corresponding input duration in microseconds.

getOutput

public ByteBuffer getOutput()

Returns a buffer containing processed output data between its position and limit. The buffer will always be a direct byte buffer with native byte order. Calling this method invalidates any previously returned buffer. The buffer will be empty if no output is available.

Returns
`ByteBuffer`	A buffer containing processed output data between its position and limit.

getSampleCountAfterProcessorApplied

public static long getSampleCountAfterProcessorApplied(
    SpeedProvider speedProvider,
    @IntRange(from = 1) int inputSampleRateHz,
    @IntRange(from = 1) long inputSamples
)

Returns the estimated number of samples output given the provided parameters.

getSpeedAdjustedTimeAsync

public void getSpeedAdjustedTimeAsync(long inputTimeUs, TimestampConsumer callback)

Calculates the time at which the inputTimeUs is outputted at after the speed changes has been applied.

Calls the callback with the output time as soon as enough audio has been processed to calculate it.

If the audio processor has ended, speeds will come out at the last processed speed of the audio processor.

Successive calls must have monotonically increasing inputTimeUs.

Can be called from any thread.

Parameters
`long inputTimeUs`	The input time, in microseconds.
`TimestampConsumer callback`	The callback called with the output time. May be called on a different thread from the caller of this method.

isActive

public boolean isActive()

Returns whether the processor is configured and will process input buffers.

isEnded

public boolean isEnded()

Returns whether this processor will return no more output from getOutput until flush has been called and more input has been queued.

queueEndOfStream

public void queueEndOfStream()

Queues an end of stream signal. After this method has been called, queueInput may not be called until after the next call to flush. Calling getOutput will return any remaining output data. Multiple calls may be required to read all of the remaining output data. isEnded will return true once all remaining output data has been read.

queueInput

public void queueInput(ByteBuffer inputBuffer)

Queues audio data between the position and limit of the inputBuffer for processing. After calling this method, processed output may be available via getOutput. Calling queueInput(ByteBuffer) again invalidates any pending output.

Parameters
`ByteBuffer inputBuffer`	The input buffer to process. It must be a direct byte buffer with native byte order. Its contents are treated as read-only. Its position will be advanced by the number of bytes consumed (which may be zero). The caller retains ownership of the provided buffer.

reset

public void reset()

Resets the processor to its unconfigured state, releasing any resources.