Dynamic Resampling. We can use a variable factor to speed up or slow down the playback. More...

#include <ResampleStream.h>

Inheritance diagram for ResampleStream:

Public Member Functions
	ResampleStream (AudioOutput &out)

	ResampleStream (AudioStream &io)

	ResampleStream (Print &out)
	Support for resampling via write.

	ResampleStream (Stream &io)
	Support for resampling via write and read.

virtual void	addNotifyAudioChange (AudioInfoSupport &bi)
	Adds target to be notified about audio changes.

virtual AudioInfo	audioInfo () override
	provides the actual input AudioInfo

AudioInfo	audioInfoOut () override
	provides the actual output AudioInfo: this is usually the same as audioInfo() unless we use a transforming stream

int	available () override

int	availableForWrite () override

bool	begin () override

bool	begin (AudioInfo from, AudioInfo to)

bool	begin (AudioInfo from, int toRate)

bool	begin (AudioInfo from, sample_rate_t toRate)

virtual bool	begin (AudioInfo info)

bool	begin (AudioInfo info, float step)

bool	begin (ResampleConfig cfg)

virtual void	clearNotifyAudioChange ()
	Deletes all change notify subscriptions.

ResampleConfig	defaultConfig ()
	Provides the default configuraiton.

void	end () override

void	flush ()
	When buffering is active, writes the buffered audio to the output.

float	getByteFactor ()

virtual Print *	getPrint ()

float	getStepSize ()
	Returns the actual step size.

float	getStepSize (float sampleRateFrom, float sampleRateTo)

virtual Stream *	getStream ()

bool	isNotifyActive ()
	Checks if the automatic AudioInfo update is active.

virtual	operator bool ()

size_t	readBytes (uint8_t *data, size_t len) override

virtual size_t	readSilence (uint8_t *buffer, size_t length)
	Source to generate silence: just sets the buffer to 0.

virtual bool	removeNotifyAudioChange (AudioInfoSupport &bi)
	Removes a target in order not to be notified about audio changes.

void	setAudioInfo (AudioInfo newInfo) override
	Defines the input AudioInfo.

void	setBuffered (bool active)
	Activates buffering to avoid small incremental writes.

void	setNotifyActive (bool flag)
	Deactivate/Reactivate automatic AudioInfo updates: (default is active)

virtual void	setOutput (AudioOutput &print)

virtual void	setOutput (Print &print) override
	Defines/Changes the output target.

void	setStepSize (float step)
	influence the sample rate

virtual void	setStream (AudioStream &stream)

virtual void	setStream (Stream &stream) override
	Defines/Changes the input & output.

void	setTargetSampleRate (int rate)

size_t	write (const uint8_t *data, size_t len) override

virtual size_t	write (uint8_t ch) override

virtual void	writeSilence (size_t len)
	Writes len bytes of silence (=0).

Protected Member Functions
template<typename T >
T	getValue (T *data, float frame_idx, int channel)
	get the interpolated value for indicated (float) index value

template<typename T >
T	lookup (T *data, int frame, int channel)
	lookup value for indicated frame & channel: index starts with -1;

virtual int	not_supported (int out, const char *msg="")

void	notifyAudioChange (AudioInfo info)

void	refillReadBuffer ()

void	setupLastSamples (AudioInfo cfg)
	Sets up the buffer for the rollover samples.

template<typename T >
void	setupLastSamples (T *data, int frame)
	store last samples to provide values for index -1

void	setupReader ()

template<typename T >
size_t	write (Print p_out, const uint8_t buffer, size_t bytes, size_t &written)
	Writes the buffer to defined output after resampling.

Protected Attributes
int	_timeout = 10

int	bytes_per_frame = 0

float	idx = 0

AudioInfo	info

bool	is_buffer_active = USE_RESAMPLE_BUFFER

bool	is_first = true

bool	is_notify_active = true

Vector< uint8_t >	last_samples {0}

Vector< AudioInfoSupport * >	notify_vector

SingleBuffer< uint8_t >	out_buffer {0}

Print *	p_out = nullptr

Print *	p_print = nullptr

Stream *	p_stream = nullptr

TransformationReader< ReformatBaseStream >	reader

float	step_size = 1.0

RingBuffer< uint8_t >	tmp_in {0}

RingBuffer< uint8_t >	tmp_out {0}

int	to_sample_rate = 0

Detailed Description

Dynamic Resampling. We can use a variable factor to speed up or slow down the playback.

Author: Phil Schatzmann

Copyright: GPLv3

Template Parameters

T

Constructor & Destructor Documentation

◆ ResampleStream() [1/2]

ResampleStream ( AudioOutput & out )

inline

Support for resampling via write. The audio information is copied from the io

◆ ResampleStream() [2/2]

ResampleStream ( AudioStream & io )

inline

Support for resampling via write and read. The audio information is copied from the io

Member Function Documentation

◆ getStepSize()

float getStepSize	(	float	sampleRateFrom,
		float	sampleRateTo
	)

inline

calculate the step size the sample rate: e.g. from 44200 to 22100 gives a step size of 2 in order to provide fewer samples

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

src/AudioTools/CoreAudio/ResampleStream.h

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ ResampleStream() [1/2]

◆ ResampleStream() [2/2]

Member Function Documentation

◆ getStepSize()