ResampleStream Class Reference

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 AudioInfo	audioInfo () override
int	available () override
int	availableForWrite () override
virtual bool	begin ()
bool	begin (AudioInfo from, int toRate)
bool	begin (AudioInfo info, float step)
bool	begin (ResampleConfig cfg)
ResampleConfig	defaultConfig ()
	Provides the default configuraiton.
virtual void	end ()
void	flush () override
	When buffering is active, writes the buffered audio to the output.
virtual Print *	getPrint ()
float	getStepSize ()
	Returns the actual step size.
float	getStepSize (float sampleRateFrom, float sampleRateTo)
virtual Stream *	getStream ()
	operator bool ()
size_t	readBytes (uint8_t *data, size_t size) override
virtual size_t	readSilence (uint8_t *buffer, size_t length)
	Source to generate silence: just sets the buffer to 0.
void	setAudioInfo (AudioInfo info) override
void	setBuffered (bool active)
	Activates buffering to avoid small incremental writes.
virtual void	setNotifyAudioChange (AudioInfoSupport &bi) override
void	setStepSize (float step)
	influence the sample rate
virtual void	setStream (Print &print)
virtual void	setStream (Stream &stream)
void	setupReader ()
virtual bool	validate (AudioInfo &info)
size_t	write (const uint8_t *buffer, size_t bytes) 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)
virtual int	not_supported (int out, const char *msg="")
void	refillReadBuffer ()
void	setupLastSamples (AudioInfo cfg)
	Sets up the buffer for the rollover samples.
template<typename T >
void	setupLastSamples (T *data, int frame)
template<typename T >
size_t	write (Print *p_out, const uint8_t *buffer, size_t bytes, size_t &written)
	Writes the buffer to p_print after resampling.

Protected Attributes
int	bytes_per_frame = 0
float	factor
float	idx = 0
AudioInfo	info
bool	is_buffer_active = false
bool	is_first = true
Vector< uint8_t >	last_samples {0}
SingleBuffer< uint8_t >	out_buffer {0}
AudioInfoSupport *	p_notify =nullptr
Print *	p_out =nullptr
Print *	p_print = nullptr
Stream *	p_stream = nullptr
TransformationReader< ResampleStream >	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

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

• src/AudioTools/ResampleStream.h