iso::synth::FFTUnit Class Reference

performs fast fourier transformation More...

#include <iso_synth_fft_unit.h>

Inherits iso::synth::ProcessUnit.

Inheritance diagram for iso::synth::FFTUnit:

[legend]Collaboration diagram for iso::synth::FFTUnit:

[legend]List of all members.

Public Member Functions
	FFTUnit ()
	default constructor
	FFTUnit (const String &pName)
	name constructor
	FFTUnit (unsigned int pChannelCount)
	parameter based contructor
	FFTUnit (const String &pName, unsigned int pChannelCount)
	parameter based contructor
	FFTUnit (FunctionType pWindowType, unsigned int pOverlap)
	parameter based contructor
	FFTUnit (const String &pName, FunctionType pWindowType, unsigned int pOverlap)
	parameter based contructor
	FFTUnit (unsigned int pChannelCount, FunctionType pWindowType, unsigned int pOverlap)
	parameter based contructor
	FFTUnit (const String &pName, unsigned int pChannelCount, FunctionType pWindowType, unsigned int pOverlap)
	parameter based contructor
	FFTUnit (FunctionType pWindowType, unsigned int pOverlap, unsigned int pFrameCount, unsigned int pChannelCount, unsigned int pRate, FanInType pFanInType=FANIN_ADD)
	parameter based contructor
	FFTUnit (const String &pName, FunctionType pWindowType, unsigned int pOverlap, unsigned int pFrameCount, unsigned int pChannelCount, unsigned int pRate, FanInType pFanInType=FANIN_ADD)
	name and parameter based contructor
	FFTUnit (const FFTUnit &pUnit)
	copy constructor
	FFTUnit (const String &pName, const FFTUnit &pUnit)
	name & copy constructor
	FFTUnit (const data::Values &pValues) throw (SynthException)
	values based constructor
virtual	~FFTUnit ()
	destructor
virtual void	process (Buffer *pBuffer) throw (SynthException)
	processes buffer
virtual String	info (bool pPropagate=false, bool pShowPorts=true) const
	obtain textual unit information
Static Public Attributes
static const String	sClassName
	default name
Protected Member Functions
void	init ()
	initializes ports
Protected Attributes
Buffer *	mAudioBuffer
	audio buffer
FunctionType	mWindowType
	window type for windowing
Channel *	mWindow
	window buffer
unsigned int	mOverlap
	number of overlaps
unsigned int	mSpectraCount
	total number of spectra per audio buffer
unsigned int	mSpectrumStartNr
	first spectrum number
unsigned int	mSpectrumNr
	current spectrum number
sample *	mFFTWAudioData
	audio data buffer for fftw
fftwf_complex *	mFFTWSpectralData
	spectral data buffer for fftw
RingBuffer *	mPreFFTAudioBuffer
	audio buffer which combines audio buffers before fft
Frame	mPreFFTBufferReadPos
	relative read position into PreFFTRingBuffer
fftwf_plan	mFFTPlan
	forward fft plan
Static Protected Attributes
static unsigned int	sUnitCount
	total number of units created so far
static FunctionType	sWindowType
	default window type for windowing
Friends
std::ostream &	operator<< (std::ostream &pOstream, const FFTUnit &pUnit)
	print unit information

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Detailed Description

performs fast fourier transformation

fourier transformation

This unit expands the basic process unit class.
It receives audio data at its audio input port and transforms it into spectral data that is output through the audio output port.
Apart from the standard configuration possibilities for processing units, this unit
allows users to specify the window type (GAUSS, HAMMING, HANN) and the number of overlaps between windows.

This unit is peculiar in that it works at the different rate than normal audio units
and in that the number of frames and channels differs at the audio input and output ports.
This values are calculated as follows (if no specified manually)

unit:
rate : synth default rate * 2.0 ^ (windowoverlap - 1)
frameCount : synth default frameCount
channelCount : synth default channelCount

input port:
rate : synth default rate
frameCount : synth default frameCount
channelCount : synth default channelCount

output port:
rate : synth default rate * 2.0 ^ (windowoverlap - 1)
frameCount : synth default frameCount / 2
channelCount : synth default channelCount * 2


SwitchPorts:
name: active channelCount: 1 defaultValue: 1.0 resizable: false function: setActive

Created by Daniel Bisig on 9/12/06.
Copyright 2006 Daniel Bisig All rights reserved.

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Constructor & Destructor Documentation

FFTUnit::FFTUnit

(

)

default constructor

FFTUnit::FFTUnit

(

const String &

pName

)

name constructor

Parameters:

pName

unit name

FFTUnit::FFTUnit

(

unsigned int

pChannelCount

)

parameter based contructor

Parameters:

pChannelCount

channel count

FFTUnit::FFTUnit	(	const String &	pName,
		unsigned int	pChannelCount
	)

parameter based contructor

Parameters:

	pName	unit name
	pChannelCount	channel count

FFTUnit::FFTUnit	(	FunctionType	pWindowType,
		unsigned int	pOverlap
	)

parameter based contructor

Parameters:

	pWindowType	window type
	pOverlap	number of overlaps

FFTUnit::FFTUnit	(	const String &	pName,
		FunctionType	pWindowType,
		unsigned int	pOverlap
	)

parameter based contructor

Parameters:

	pName	unit name
	pWindowType	window type
	pOverlap	number of overlaps

FFTUnit::FFTUnit	(	unsigned int	pChannelCount,
		FunctionType	pWindowType,
		unsigned int	pOverlap
	)

parameter based contructor

Parameters:

	pChannelCount	channel count
	pWindowType	window type
	pOverlap	number of overlaps

FFTUnit::FFTUnit	(	const String &	pName,
		unsigned int	pChannelCount,
		FunctionType	pWindowType,
		unsigned int	pOverlap
	)

parameter based contructor

Parameters:

	pName	unit name
	pChannelCount	channel count
	pWindowType	window type
	pOverlap	number of overlaps

FFTUnit::FFTUnit	(	FunctionType	pWindowType,
		unsigned int	pOverlap,
		unsigned int	pFrameCount,
		unsigned int	pChannelCount,
		unsigned int	pRate,
		FanInType	pFanInType = FANIN_ADD
	)

parameter based contructor

Parameters:

	pWindowType	window type
	pOverlap	number of overlaps
	pFrameCount	number of frames
	pChannelCount	number of channels
	pRate	samping rate
	pFanInType	strategy for combining audio buffers in case this unit is connected to several units

FFTUnit::FFTUnit	(	const String &	pName,
		FunctionType	pWindowType,
		unsigned int	pOverlap,
		unsigned int	pFrameCount,
		unsigned int	pChannelCount,
		unsigned int	pRate,
		FanInType	pFanInType = FANIN_ADD
	)

name and parameter based contructor

Parameters:

	pName	unit name
	pWindowType	window type
	pOverlap	number of overlaps
	pFrameCount	number of frames
	pChannelCount	number of channels
	pRate	samping rate
	pFanInType	strategy for combining audio buffers in case this unit is connected to several units

Exceptions:

SynthException

pFreqBinCount or pFrameCount not a power of two

FFTUnit::FFTUnit

(

const FFTUnit &

pUnit

)

copy constructor

Parameters:

pUnit

unit to copy properties from

constructor copies frameCount, channelCount and rate but not unit name

FFTUnit::FFTUnit	(	const String &	pName,
		const FFTUnit &	pUnit
	)

name & copy constructor

Parameters:

	pName	unit name
	pUnit	unit to copy properties from

constructor copies frameCount, channelCount and rate but not unit name

FFTUnit::FFTUnit

(

const data::Values &

pValues

)

throw (SynthException)

values based constructor

Parameters:

pValues

unit values

Exceptions:

SynthException

failed to create unit

pValues structure & data types: 0: const String& : unit name 1: FunctionType : window type 2: unsigned int : number of window overlaps 3: unsigned int : number of frames 4: unsigned int : number of channels 5: unsigned int : samping rate

FFTUnit::~FFTUnit

(

)

[virtual]

destructor

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Member Function Documentation

void FFTUnit::process

(

Buffer *

pBuffer

)

throw (SynthException) [virtual]

processes buffer

Parameters:

pBuffer

buffer to process

Reimplemented from iso::synth::ProcessUnit.

base::String FFTUnit::info	(	bool	pPropagate = false,
		bool	pShowPorts = true
	)			const [virtual]

obtain textual unit information

Parameters:

	pPropagate	if true, the unit calls the info methods of its input ports
	pShowPorts	print port information

Returns:

String containing unit information

Reimplemented from iso::synth::ProcessUnit.

void FFTUnit::init

(

)

[protected]

initializes ports

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Friends And Related Function Documentation

std::ostream& operator<<	(	std::ostream &	pOstream,
		const FFTUnit &	pUnit
	)			[friend]

print unit information

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Member Data Documentation

const base::String FFTUnit::sClassName [static]

default name

Reimplemented from iso::synth::ProcessUnit.

unsigned int FFTUnit::sUnitCount [static, protected]

total number of units created so far

Reimplemented from iso::synth::ProcessUnit.

FunctionType FFTUnit::sWindowType [static, protected]

default window type for windowing

Buffer* iso::synth::FFTUnit::mAudioBuffer [protected]

audio buffer

FunctionType iso::synth::FFTUnit::mWindowType [protected]

window type for windowing

Channel* iso::synth::FFTUnit::mWindow [protected]

window buffer

unsigned int iso::synth::FFTUnit::mOverlap [protected]

number of overlaps

unsigned int iso::synth::FFTUnit::mSpectraCount [protected]

total number of spectra per audio buffer

unsigned int iso::synth::FFTUnit::mSpectrumStartNr [protected]

first spectrum number

unsigned int iso::synth::FFTUnit::mSpectrumNr [protected]

current spectrum number

sample* iso::synth::FFTUnit::mFFTWAudioData [protected]

audio data buffer for fftw

fftwf_complex* iso::synth::FFTUnit::mFFTWSpectralData [protected]

spectral data buffer for fftw

RingBuffer* iso::synth::FFTUnit::mPreFFTAudioBuffer [protected]

audio buffer which combines audio buffers before fft

Frame iso::synth::FFTUnit::mPreFFTBufferReadPos [protected]

relative read position into PreFFTRingBuffer

fftwf_plan iso::synth::FFTUnit::mFFTPlan [protected]

forward fft plan

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

• /Users/dbisig/programming/swarms/trunk/synth/trunk/code/unit/proc/fft/iso_synth_fft_unit.h
• /Users/dbisig/programming/swarms/trunk/synth/trunk/code/unit/proc/fft/iso_synth_fft_unit.cpp

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