oboe::FullDuplexStream Class Reference

#include <FullDuplexStream.h>

Inheritance diagram for oboe::FullDuplexStream:

Public Member Functions
void	setInputStream (AudioStream *stream)
AudioStream *	getInputStream ()
void	setOutputStream (AudioStream *stream)
AudioStream *	getOutputStream ()
virtual Result	start ()
virtual Result	stop ()
virtual ResultWithValue< int32_t >	readInput (int32_t numFrames)
virtual DataCallbackResult	onBothStreamsReady (const void *inputData, int numInputFrames, void *outputData, int numOutputFrames)=0
DataCallbackResult	onAudioReady (AudioStream *, void *audioData, int numFrames)
void	setNumInputBurstsCushion (int32_t numBursts)
int32_t	getNumInputBurstsCushion () const
void	setMinimumFramesBeforeRead (int32_t numFrames)
int32_t	getMinimumFramesBeforeRead () const
Public Member Functions inherited from oboe::AudioStreamDataCallback
virtual DataCallbackResult	onAudioReady (AudioStream *audioStream, void *audioData, int32_t numFrames)=0

Detailed Description

FullDuplexStream can be used to synchronize an input and output stream.

For the builder of the output stream, call setDataCallback() with this object.

When both streams are ready, onAudioReady() of the output stream will call onBothStreamsReady(). Callers must override onBothStreamsReady().

To ensure best results, open an output stream before the input stream. Call inputBuilder.setBufferCapacityInFrames(mOutputStream->getBufferCapacityInFrames() * 2). Also, call inputBuilder.setSampleRate(mOutputStream->getSampleRate()).

Callers must call setInputStream() and setOutputStream(). Call start() to start both streams and stop() to stop both streams. Caller is responsible for closing both streams.

Callers should handle error callbacks with setErrorCallback() for the output stream. When an error callback occurs for the output stream, Oboe will stop and close the output stream. The caller is responsible for stopping and closing the input stream. The caller should also reopen and restart both streams when the error callback is ErrorDisconnected. See the LiveEffect sample as an example of this.

Member Function Documentation

getInputStream()

AudioStream * oboe::FullDuplexStream::getInputStream ( )

inline

Gets the input stream

Returns

the input stream

getMinimumFramesBeforeRead()

int32_t oboe::FullDuplexStream::getMinimumFramesBeforeRead ( ) const

inline

Gets the minimum number of frames in the input stream buffer before calling readInput().

Returns

minimum number of frames before reading

getNumInputBurstsCushion()

int32_t oboe::FullDuplexStream::getNumInputBurstsCushion ( ) const

inline

Get the number of bursts left in the input buffer as a cushion.

Returns

number of bursts in the input buffer as a cushion

getOutputStream()

AudioStream * oboe::FullDuplexStream::getOutputStream ( )

inline

Gets the output stream

Returns

the output stream

onAudioReady()

DataCallbackResult oboe::FullDuplexStream::onAudioReady ( AudioStream *  , void *  audioData, int  numFrames  )

inline

Called when the output stream is ready to process audio. This in return calls onBothStreamsReady() when data is available on both streams. Callers should call this function when the output stream is ready. Callers must override onBothStreamsReady().

Parameters

audioStream	pointer to the associated stream
audioData	a place to put output data
numFrames	number of frames to be processed

Returns

DataCallbackResult::Continue or DataCallbackResult::Stop

onBothStreamsReady()

virtual DataCallbackResult oboe::FullDuplexStream::onBothStreamsReady ( const void *  inputData, int  numInputFrames, void *  outputData, int  numOutputFrames  )

pure virtual

Called when data is available on both streams. Caller should override this method. numInputFrames and numOutputFrames may be zero.

Parameters

inputData	buffer containing input data
numInputFrames	number of input frames
outputData	a place to put output data
numOutputFrames	number of output frames

Returns

DataCallbackResult::Continue or DataCallbackResult::Stop

readInput()

virtual ResultWithValue< int32_t > oboe::FullDuplexStream::readInput ( int32_t  numFrames )

inlinevirtual

Reads input from the input stream. Callers should not call this directly as this is called in onAudioReady().

Parameters

numFrames

Returns

result of the operation

setInputStream()

void oboe::FullDuplexStream::setInputStream ( AudioStream *  stream )

inline

Sets the input stream. Calling this is mandatory.

Parameters

stream

the output stream

setMinimumFramesBeforeRead()

void oboe::FullDuplexStream::setMinimumFramesBeforeRead ( int32_t  numFrames )

inline

Minimum number of frames in the input stream buffer before calling readInput().

Parameters

numFrames

number of bursts in the input buffer as a cushion

setNumInputBurstsCushion()

void oboe::FullDuplexStream::setNumInputBurstsCushion ( int32_t  numBursts )

inline

This is a cushion between the DSP and the application processor cursors to prevent collisions. Typically 0 for latency measurements or 1 for glitch tests.

Parameters

numBursts

number of bursts to leave in the input buffer as a cushion

setOutputStream()

void oboe::FullDuplexStream::setOutputStream ( AudioStream *  stream )

inline

Sets the output stream. Calling this is mandatory.

Parameters

stream

the output stream

start()

virtual Result oboe::FullDuplexStream::start ( )

inlinevirtual

Attempts to start both streams. Please call setInputStream() and setOutputStream() before calling this function.

Returns

result of the operation

stop()

virtual Result oboe::FullDuplexStream::stop ( )

inlinevirtual

Stops both streams. Returns Result::OK if neither stream had an error during close.

Returns

result of the operation

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The documentation for this class was generated from the following file:

• include/oboe/FullDuplexStream.h