ChannelMixingAudioProcessor

Kotlin |Java

@UnstableApi
class ChannelMixingAudioProcessor : BaseAudioProcessor

kotlin.Any
↳	androidx.media3.common.audio.BaseAudioProcessor
	↳	androidx.media3.common.audio.ChannelMixingAudioProcessor

An AudioProcessor that handles mixing and scaling audio channels. Call putChannelMixingMatrix specifying mixing matrices to apply for each possible input channel count before using the audio processor. Input and output are 16-bit PCM.

Summary

Public constructors
`ChannelMixingAudioProcessor()` Creates a new audio processor for mixing and scaling audio channels.

Public functions
`Unit`	`putChannelMixingMatrix(matrix: ChannelMixingMatrix!)` Stores a channel mixing matrix for processing audio with a given `channel count`.
`Unit`	`queueInput(inputBuffer: ByteBuffer!)` Queues audio data between the position and limit of the `inputBuffer` for processing.

Protected functions
`AudioProcessor.AudioFormat!`	`onConfigure(inputAudioFormat: AudioProcessor.AudioFormat!)` Called when the processor is configured for a new input format.

Inherited Constants

From androidx.media3.common.audio.AudioProcessor

const ByteBuffer!

EMPTY_BUFFER

An empty, direct ByteBuffer.

Inherited functions

From androidx.media3.common.audio.AudioProcessor

Long

getDurationAfterProcessorApplied(durationUs: Long)

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

From androidx.media3.common.audio.BaseAudioProcessor

`AudioProcessor.AudioFormat!`	`configure(inputAudioFormat: AudioProcessor.AudioFormat!)` Configures the processor to process input audio with the specified format.
`Unit`	`flush()` Clears any buffered data and pending output.
`ByteBuffer!`	`@CallSuper getOutput()` Returns a buffer containing processed output data between its position and limit.
`Boolean`	`hasPendingOutput()` Returns whether the current output buffer has any data remaining.
`Boolean`	`@CallSuper isActive()` Returns whether the processor is configured and will process input buffers.
`Boolean`	`@CallSuper isEnded()` Returns whether this processor will return no more output from `getOutput` until `flush` has been called and more input has been queued.
`Unit`	`onFlush()` Called when the processor is flushed, directly or as part of resetting.
`Unit`	`onQueueEndOfStream()` Called when the end-of-stream is queued to the processor.
`Unit`	`onReset()` Called when the processor is reset.
`Unit`	`queueEndOfStream()` Queues an end of stream signal.
`ByteBuffer!`	`replaceOutputBuffer(size: Int)` Replaces the current output buffer with a buffer of at least `size` bytes and returns it.
`Unit`	`reset()` Resets the processor to its unconfigured state, releasing any resources.

Inherited properties

From androidx.media3.common.audio.BaseAudioProcessor

`AudioProcessor.AudioFormat!`	`inputAudioFormat` The current input audio format.
`AudioProcessor.AudioFormat!`	`outputAudioFormat` The current output audio format.

Public constructors

ChannelMixingAudioProcessor

ChannelMixingAudioProcessor()

Creates a new audio processor for mixing and scaling audio channels.

Public functions

putChannelMixingMatrix

fun putChannelMixingMatrix(matrix: ChannelMixingMatrix!): Unit

Stores a channel mixing matrix for processing audio with a given channel count. Overwrites any previously stored matrix for the same input channel count.

queueInput

fun queueInput(inputBuffer: ByteBuffer!): Unit

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
`inputBuffer: ByteBuffer!`	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.

Protected functions

onConfigure

protected fun onConfigure(inputAudioFormat: AudioProcessor.AudioFormat!): AudioProcessor.AudioFormat!

Called when the processor is configured for a new input format.

Throws
`androidx.media3.common.audio.AudioProcessor.UnhandledAudioFormatException`