Delay effect that filters the repeat delay. More...

#include <AudioEffectsSuite.h>

Inheritance diagram for FilteredDelay:

Public Member Functions
	FilteredDelay (FilteredDelay &copy)=default

	FilteredDelay (int delayInSamples, int sample_rate=44100)

	~FilteredDelay ()=default

virtual bool	active ()
	determines if the effect is active

virtual effectsuite_t	applyFilter (effectsuite_t sampVal)

FilteredDelay *	clone () override

effectsuite_t	envelope (effectsuite_t sample)

int	id ()
	Allows to identify an effect.

effect_t	process (effect_t inputSample) override
	see applyFilter

effectsuite_t	processDouble (effectsuite_t inputSample) override

virtual void	setActive (bool value)
	sets the effect active/inactive

bool	setChebyICoefficients (effectsuite_t cutFreq, bool shelfType, effectsuite_t ripple)

void	setDelayGain (effectsuite_t gain)

void	setFeedbackGain (effectsuite_t gain)

void	setId (int id)
	Allows to identify an effect.

void	setupDelayEffectBase (const int bufferSizeSamples)

Protected Member Functions
void	allocateBufferMemory ()

void	capGain (effectsuite_t &gain)

bool	changeChebyICoefficients (effectsuite_t cutFreq, bool shelfType, effectsuite_t ripple, int poles)

void	clearMemory ()

int16_t	clip (int32_t in, int16_t clipLimit=32767, int16_t resultLimit=32767)
	generic clipping method

void	copyParent (AudioEffect *copy)

void	delaySample (effectsuite_t inputSample)

effectsuite_t	getInterpolatedOut (effectsuite_t bufferIndex)

void	incBufferIndex ()

void	incDelayBuffReadIndex (effectsuite_t indexInc)

void	incDelayBuffWriteIndex ()

effectsuite_t	rms (effectsuite_t sample)

bool	setDelayBuffer (int bufferSizeSamples)

void	setDelayBuffReadIndex (effectsuite_t index)

bool	setSimpleLpf (int order)

void	storeSample (effectsuite_t inputSample)

Static Protected Member Functions
static effectsuite_t **	setInterpolationTable ()

Protected Attributes
bool	active_flag = true

int	bufferIndex = 0

effectsuite_t	currentDelayReadIndex = 0

int	currentDelayWriteIndex = 0

effectsuite_t *	delayBuffer = 0

effectsuite_t	delayGain = .707

int	delayTimeSamples = 44100

bool	error

effectsuite_t	feedbackGain = 0.0

int	filterOrder = 0

effectsuite_t *	firBuffer = 0

effectsuite_t *	firCoefficients = 0

effectsuite_t *	firTemp = 0

int	id_value = -1

effectsuite_t *	iirBuffer = 0

effectsuite_t *	iirCoefficients = 0

effectsuite_t *	iirTemp = 0

int	maxDelayBufferSize = 441000

effectsuite_t *	rmsBuffer = new effectsuite_t[rmsWindowSize]

int	rmsBufferIndex = 0

const int	rmsWindowSize = 128

int	samplingRate = 0

Static Protected Attributes
static const int	interpOrder = 4

static const int	interpResolution = 1000

Detailed Description

Delay effect that filters the repeat delay.

Author: Matthew Hamilton

Copyright: MIT License

Constructor & Destructor Documentation

◆ FilteredDelay() [1/2]

FilteredDelay	(	int	delayInSamples,
		int	sample_rate = `44100`
	)

inline

Constructor

◆ FilteredDelay() [2/2]

FilteredDelay ( FilteredDelay & copy )

default

◆ ~FilteredDelay()

~FilteredDelay ( )

default

Destructor

Member Function Documentation

◆ active()

virtual bool active ( )

inlinevirtualinherited

determines if the effect is active

◆ allocateBufferMemory()

void allocateBufferMemory ( )

inlineprotectedinherited

will allocate memory to a buffer given the current filter order and set all values == 0.00

◆ applyFilter()

virtual effectsuite_t applyFilter ( effectsuite_t sampVal )

inlinevirtualinherited

with the current filter coefficients this method filters a sample then stores it the sample Buffer and increments the index

Parameters

sampVal is the sample to be processed

Returns: filtered audio sample

◆ capGain()

void capGain ( effectsuite_t & gain )

inlineprotected

capGain: caps gain to a range of 1 and -1;

Parameters

gain	address of gain value

◆ changeChebyICoefficients()

bool changeChebyICoefficients	(	effectsuite_t	cutFreq,
		bool	shelfType,
		effectsuite_t	ripple,
		int	poles
	)

inlineprotectedinherited

set firCoefficients and iirCoefficients for required chebyshev type I filter sampleBuffer memory is also set @params cutFreq normalised cutoff frequency (0 < x < .5) @params shelfType bool filter shelf type, false = low pass, true = high pass @params ripple percentage ripple (<.2929) @params poles number of poles

Returns: boolean false on error and true on success

◆ clearMemory()

void clearMemory ( )

inlineprotectedinherited

checks internal memory storage of filter coeffcients and deletes if required

◆ clip()

int16_t clip	(	int32_t	in,
		int16_t	clipLimit = `32767`,
		int16_t	resultLimit = `32767`
	)

inlineprotectedinherited

generic clipping method

◆ clone()

FilteredDelay * clone ( )

inlineoverridevirtual

Implements AudioEffect.

◆ copyParent()

void copyParent ( AudioEffect * copy )

inlineprotectedinherited

◆ delaySample()

void delaySample ( effectsuite_t inputSample )

inlineprotectedinherited

store input sample into the delay buffer and increment currentDelayWriteIndex for tracking when to loop back to start of buffer

Parameters

inputSample sample to be stored for delay (effectsuite_t)

◆ envelope()

effectsuite_t envelope ( effectsuite_t sample )

inlineinherited

detect the envelop of an incoming signal

Parameters

sample the incoming signal sample value

Returns: returns envelope dection signal sample value

◆ getInterpolatedOut()

effectsuite_t getInterpolatedOut ( effectsuite_t bufferIndex )

inlineprotectedinherited

get the value of the requested buffer index by interpolating other points

Parameters

bufferIndex The required buffer index

Returns: interpolated output

◆ id()

int id ( )

inlineinherited

Allows to identify an effect.

◆ incBufferIndex()

void incBufferIndex ( )

inlineprotectedinherited

increment the buffer index and wrap it to the filter order

◆ incDelayBuffReadIndex()

void incDelayBuffReadIndex ( effectsuite_t indexInc )

inlineprotectedinherited

Increments the currentDelayBufferReadIndex by indexInc

Parameters

indexInc The amount to increment the delay buffer index

◆ incDelayBuffWriteIndex()

void incDelayBuffWriteIndex ( )

inlineprotectedinherited

Increments the currentDelayWriteBufferIndex by 1

◆ process()

effect_t process ( effect_t inputSample )

inlineoverridevirtual

see applyFilter

Reimplemented from FilterEffectBase.

◆ processDouble()

effectsuite_t processDouble ( effectsuite_t inputSample )

inlineoverridevirtual

apply the DSP effect

Reimplemented from FilterEffectBase.

◆ rms()

effectsuite_t rms ( effectsuite_t sample )

inlineprotectedinherited

root mean square of signal over a specific sample window

◆ setActive()

virtual void setActive ( bool value )

inlinevirtualinherited

sets the effect active/inactive

◆ setChebyICoefficients()

bool setChebyICoefficients	(	effectsuite_t	cutFreq,
		bool	shelfType,
		effectsuite_t	ripple
	)

inlineinherited

changes the current Chebyshev type 1 coefficients without altering the filter order. This allows for use in an audio process thread as it avoids dynamic allocation of memory. Filter sample and coefficient buffers are unaltered for initialising a chebyshev type 1 filter

See also: setChebyICoefficients @params cutFreq normalised cutoff frequency (0 < x < .5) @params shelfType bool Filters shelf type, false = low pass, true = high pass @params ripple percentage ripple (<.2929)

Returns: boolean false on error and true on success

◆ setDelayBuffer()

bool setDelayBuffer ( int bufferSizeSamples )

inlineprotectedinherited

Allocates memory for delay buffer and initialises all elements to 0

Parameters

bufferSizeSamples the size of delay buffer to be used

Returns: false and error description if there's a problem, or sets the internal delay buffer and returns true

◆ setDelayBuffReadIndex()

void setDelayBuffReadIndex ( effectsuite_t index )

inlineprotectedinherited

sets the currentDelayBufferReadIndex by indexInc (Currently no wrapping)

Parameters

index the read index index required

◆ setDelayGain()

void setDelayGain ( effectsuite_t gain )

inline

setDelayGain: sets the delay gain to a value between 1 and -1

Parameters

gainrequired delay gain. Values beyond 1 and -1 are capped to the maximum to avoid idiocy. Negative velus invoke a phase inversion.

See also: setFeedbackGain

◆ setFeedbackGain()

void setFeedbackGain ( effectsuite_t gain )

inline

setDelayGain: sets the feedback gain to a value between 1 and -1

Parameters

gain	required delay gain. Values beyond 1 and -1 are capped to the maximum to avoid idiocy. Negative velus invoke a phase inversion.

See also: setDelayGain

◆ setId()

void setId ( int id )

inlineinherited

Allows to identify an effect.

◆ setInterpolationTable()

static effectsuite_t ** setInterpolationTable ( )

inlinestaticprotectedinherited

Sets the internal lagrange interpolation table. Ideally it should be shared amongst all

Returns: false and an error description if there's a problem, or sets the interpolation lookup table and returns true

◆ setSimpleLpf()

bool setSimpleLpf ( int order )

inlineprotectedinherited

a simple normalised fir low pass filter @params order number of delay coefficients

◆ setupDelayEffectBase()

void setupDelayEffectBase ( const int bufferSizeSamples )

inlineinherited

<Description#>

Parameters

bufferSizeSamples <bufferSizeSamples description#>

◆ storeSample()

void storeSample ( effectsuite_t inputSample )

inlineprotectedinherited

store input sample into the delay buffer

Parameters

inputSample sample to be stored for delay (effectsuite_t)

Member Data Documentation

◆ active_flag

bool active_flag = true

protectedinherited

◆ bufferIndex

int bufferIndex = 0

protectedinherited

current buffer index

◆ currentDelayReadIndex

effectsuite_t currentDelayReadIndex = 0

protectedinherited

◆ currentDelayWriteIndex

int currentDelayWriteIndex = 0

protectedinherited

◆ delayBuffer

effectsuite_t* delayBuffer = 0

protectedinherited

buffer to stored audio buffer for delay effects

◆ delayGain

effectsuite_t delayGain = .707

protected

◆ delayTimeSamples

int delayTimeSamples = 44100

protectedinherited

the delay time of signal in samples

◆ error

bool error

protectedinherited

internal class error boolean

◆ feedbackGain

effectsuite_t feedbackGain = 0.0

protected

◆ filterOrder

int filterOrder = 0

protectedinherited

order of delay filter including the zero delay coefficients

◆ firBuffer

effectsuite_t* firBuffer = 0

protectedinherited

buffer to hold forward delay sample data

◆ firCoefficients

effectsuite_t* firCoefficients = 0

protectedinherited

Numerator coefficients in delay filter firCoefficients[0] z^0 coeffcieint firCoefficients[1] z^-1 coefficient

◆ firTemp

effectsuite_t* firTemp = 0

protectedinherited

hold temporary values for fir coeffcient buffer

◆ id_value

int id_value = -1

protectedinherited

◆ iirBuffer

effectsuite_t* iirBuffer = 0

protectedinherited

buffer to hold backward delay sample data

◆ iirCoefficients

effectsuite_t* iirCoefficients = 0

protectedinherited

Denomiator coefficients in delay filter

See also: firCoefficients

◆ iirTemp

effectsuite_t* iirTemp = 0

protectedinherited

hold temporary values for iir coeffcient buffer

◆ interpOrder

const int interpOrder = 4

staticprotectedinherited

◆ interpResolution

const int interpResolution = 1000

staticprotectedinherited

◆ maxDelayBufferSize

int maxDelayBufferSize = 441000

protectedinherited

Maximum number of samples that can be stored in delayBuffer

◆ rmsBuffer

effectsuite_t* rmsBuffer = new effectsuite_t[rmsWindowSize]

protectedinherited

RMS window buffer

◆ rmsBufferIndex

int rmsBufferIndex = 0

protectedinherited

current write index of rmsBuffer

◆ rmsWindowSize

const int rmsWindowSize = 128

protectedinherited

window size in samples of rms window

◆ samplingRate

int samplingRate = 0

protectedinherited

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

src/AudioTools/AudioLibs/AudioEffectsSuite.h

Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ FilteredDelay() [1/2]

◆ FilteredDelay() [2/2]

◆ ~FilteredDelay()

Member Function Documentation

◆ active()

◆ allocateBufferMemory()

◆ applyFilter()

◆ capGain()

◆ changeChebyICoefficients()

◆ clearMemory()

◆ clip()

◆ clone()

◆ copyParent()

◆ delaySample()

◆ envelope()

◆ getInterpolatedOut()

◆ id()

◆ incBufferIndex()

◆ incDelayBuffReadIndex()

◆ incDelayBuffWriteIndex()

◆ process()

◆ processDouble()

◆ rms()

◆ setActive()

◆ setChebyICoefficients()

◆ setDelayBuffer()

◆ setDelayBuffReadIndex()

◆ setDelayGain()

◆ setFeedbackGain()

◆ setId()

◆ setInterpolationTable()

◆ setSimpleLpf()

◆ setupDelayEffectBase()

◆ storeSample()

Member Data Documentation

◆ active_flag

◆ bufferIndex

◆ currentDelayReadIndex

◆ currentDelayWriteIndex

◆ delayBuffer

◆ delayGain

◆ delayTimeSamples

◆ error

◆ feedbackGain

◆ filterOrder

◆ firBuffer

◆ firCoefficients

◆ firTemp

◆ id_value

◆ iirBuffer

◆ iirCoefficients

◆ iirTemp

◆ interpOrder

◆ interpResolution

◆ maxDelayBufferSize

◆ rmsBuffer

◆ rmsBufferIndex

◆ rmsWindowSize

◆ samplingRate