AudioRealFFT Class Reference

AudioFFT using RealFFT. More...

#include <AudioRealFFT.h>

Inheritance diagram for AudioRealFFT:

Public Member Functions
virtual void	addNotifyAudioChange (AudioInfoSupport &bi)
	Adds target to be notified about audio changes.
virtual AudioInfo	audioInfo () override
	provides the actual input AudioInfo
virtual AudioInfo	audioInfoOut ()
int	available () override
	Data available for reverse fft.
int	availableForWrite () override
	We try to fill the buffer at once.
bool	begin () override
	starts the processing
bool	begin (AudioFFTConfig info)
	starts the processing
void	clearBins ()
	clears the fft data
virtual void	clearNotifyAudioChange ()
	Deletes all change notify subscriptions.
AudioFFTConfig &	config ()
	Provides the actual configuration.
AudioFFTConfig	defaultConfig (RxTxMode mode=TX_MODE)
	Provides the default configuration.
FFTDriver *	driver ()
FFTDriverRealFFT *	driverEx ()
void	end () override
	Release the allocated memory.
virtual void	flush () override
float	frequency (int bin)
	Determines the frequency of the indicated bin.
int	frequencyToBin (int freq)
	Determine the bin number from the frequency.
bool	getBin (int pos, FFTBin &bin)
	gets the value of a bin
float *	imgArray ()
	Provides the complex array returned by the FFT
bool	isNotifyActive ()
	Checks if the automatic AudioInfo update is active.
int	length ()
	The number of samples.
float	magnitude (int bin)
float	magnitudeFast (int bin)
float *	magnitudes ()
float *	magnitudesFast ()
	operator bool () override
float	phase (int bin)
	calculates the phase
size_t	readBytes (uint8_t *data, size_t len) override
	Provides the result of a reverse FFT.
virtual size_t	readSilence (uint8_t *buffer, size_t length)
	Source to generate silence: just sets the buffer to 0.
float *	realArray ()
	Provides the real array returned by the FFT.
virtual bool	removeNotifyAudioChange (AudioInfoSupport &bi)
	Removes a target in order not to be notified about audio changes.
void	reset ()
	Just resets the current_pos e.g. to start a new cycle.
AudioFFTResult	result ()
	Determines the result values in the max magnitude bin.
template<int N>
void	resultArray (AudioFFTResult(&result)[N])
	Determines the N biggest result values.
unsigned long	resultTime ()
unsigned long	resultTimeBegin ()
	time before the fft
void	setAudioInfo (AudioInfo info) override
	Notify change of audio information.
bool	setBin (int idx, float real, float img)
	sets the value of a bin
bool	setBin (int pos, FFTBin &bin)
	sets the value of a bin
void	setNotifyActive (bool flag)
	Deactivate/Reactivate automatic AudioInfo updates: (default is active)
int	size ()
	The number of bins used by the FFT which are relevant for the result.
size_t	write (const uint8_t *data, size_t len) override
	Provide the audio data as FFT input.
virtual size_t	write (uint8_t ch) override
virtual void	writeSilence (size_t len)
	Writes len bytes of silence (=0).

Protected Member Functions
int	bytesPerSample ()
template<typename T >
void	fft ()
template<int N>
void	insertSorted (AudioFFTResult(&result)[N], AudioFFTResult tmp)
	make sure that we do not reuse already found results
bool	isPowerOfTwo (uint16_t x)
virtual int	not_supported (int out, const char *msg="")
void	notifyAudioChange (AudioInfo info)
template<typename T >
void	processSamples (const void *data, size_t count)
void	refillReadBuffer ()
void	rfft ()
	reverse fft
void	rfftWriteData (BaseBuffer< uint8_t > &data)
	write reverse fft result to buffer to make it available for readBytes
template<typename T >
T	windowedSample (T sample, int pos)
template<typename T >
void	writeIFFT (float *data, int len)
bool	writeStrideBuffer (uint8_t *buffer, size_t len)

Protected Attributes
int	_timeout = 10
int	bins = 0
AudioFFTConfig	cfg
int	current_pos = 0
bool	has_rfft_data = false
AudioInfo	info
bool	is_notify_active = true
Vector< float >	l_magnitudes {0}
Vector< AudioInfoSupport * >	notify_vector
FFTDriver *	p_driver = nullptr
FFTInverseOverlapAdder	rfft_add {0}
RingBuffer< uint8_t >	rfft_data {0}
Vector< float >	step_data {0}
SingleBuffer< uint8_t >	stride_buffer {0}
unsigned long	timestamp = 0l
unsigned long	timestamp_begin = 0l
RingBuffer< uint8_t >	tmp_in {0}
RingBuffer< uint8_t >	tmp_out {0}

Detailed Description

AudioFFT using RealFFT.

Author

Phil Schatzmann

Copyright

GPLv3

Member Function Documentation

addNotifyAudioChange()

virtual void addNotifyAudioChange ( AudioInfoSupport &  bi )

inlinevirtualinherited

Adds target to be notified about audio changes.

Reimplemented in CodecNOP, EncodedAudioOutput, EncodedAudioStream, AACDecoderFDK, DecoderBasic, MP3DecoderHelix, MP3DecoderMAD, OggContainerDecoder, Pipeline, and Pipeline::ModifyingStreamAdapter.

audioInfo()

virtual AudioInfo audioInfo ( )

inlineoverridevirtualinherited

provides the actual input AudioInfo

Implements AudioInfoSupport.

Reimplemented in JupyterAudioT< T >, MozziStream, TimerCallbackAudioStream, PureDataStream, AdapterAudioOutputToAudioStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, and InputMerge< T >.

audioInfoOut()

virtual AudioInfo audioInfoOut ( )

inlinevirtualinherited

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

Reimplemented in PureDataStream, PWMAudioOutput, ChannelFormatConverterStreamT< T >, ChannelFormatConverterStream, NumberFormatConverterStreamT< TFrom, TTo >, NumberFormatConverterStream, FormatConverterStream, Pipeline, and ResampleStream.

available()

int available ( )

inlineoverridevirtualinherited

Data available for reverse fft.

Reimplemented from BaseStream.

availableForWrite()

int availableForWrite ( )

inlineoverridevirtualinherited

We try to fill the buffer at once.

Reimplemented from BaseStream.

begin()

bool begin ( )

inlineoverridevirtualinherited

starts the processing

Reimplemented from BaseStream.

driver()

FFTDriver * driver ( )

inlineinherited

provides access to the FFTDriver which implements the basic FFT functionality

end()

void end ( )

inlineoverridevirtualinherited

Release the allocated memory.

Reimplemented from BaseStream.

flush()

virtual void flush ( )

inlineoverridevirtualinherited

Reimplemented from Print.

Reimplemented in ResampleStream, BufferedTaskStream, and BufferedStream.

magnitude()

float magnitude ( int  bin )

inlineinherited

Calculates the magnitude of the fft result to determine the max value (bin is 0 to size())

magnitudes()

float * magnitudes ( )

inlineinherited

Provides the magnitudes as array of size size(). Please note that this method is allocating additinal memory!

magnitudesFast()

float * magnitudesFast ( )

inlineinherited

Provides the magnitudes w/o calling the square root function as array of size size(). Please note that this method is allocating additinal memory!

operator bool()

operator bool ( )

inlineoverridevirtualinherited

Reimplemented from AudioStream.

readBytes()

size_t readBytes ( uint8_t *  data, size_t  len  )

inlineoverridevirtualinherited

Provides the result of a reverse FFT.

Reimplemented from AudioStream.

resultTime()

unsigned long resultTime ( )

inlineinherited

time after the fft: time when the last result was provided - you can poll this to check if we have a new result

setAudioInfo()

void setAudioInfo ( AudioInfo  info )

inlineoverridevirtualinherited

Notify change of audio information.

Reimplemented from AudioStream.

write() [1/2]

size_t write ( const uint8_t *  data, size_t  len  )

inlineoverridevirtualinherited

Provide the audio data as FFT input.

Reimplemented from AudioStream.

write() [2/2]

virtual size_t write ( uint8_t  ch )

inlineoverridevirtualinherited

Reimplemented in BufferedTaskStream, and BufferedStream.

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

• src/AudioTools/AudioLibs/AudioRealFFT.h