A class that shifts the pitch of input audio up or down by a number of semitones. More...

#include <omSoundPitchShifter.h>

Inheritance diagram for om::sound::filters::PitchShifter:

Public Member Functions
	PitchShifter ()
	Create a new pitch shifter with no pitch shift. More...

	PitchShifter (Float newSemitoneShift)
	Create a new pitch shifter which shifts the input audio by the specified number of semitones. More...

Float	getShift () const
	Return the current pitch shift amount expressed as a frequency multiplier. More...

void	setShift (Float newShift)
	Set the pitch shift amount, expressed as a frequency multiplier. More...

Float	getSemitoneShift () const
	Return the current pitch shift amount in signed semitones. More...

void	setSemitoneShift (Float newSemitones)
	Set the current pitch shift amount in signed semitones. More...

Float	getBufferLength () const
	Return the length in seconds of the FFT buffer used when doing pitch shifting. More...

void	setBufferLength (Float newBufferLength)
	Set the length in seconds of the FFT buffer used when doing pitch shifting. More...

Size	getOversampling () const
	Return the oversampling factor currently used by this pitch shifter. More...

void	setOversampling (Size newOversampling)
	Set the oversampling factor currently used by this pitch shifter. More...

Gain	getMix () const
	Return the ratio of input signal to pitch shifted signal sent to the output of the pitch shifter. More...

void	setMix (Gain newMix)
	Set the ratio of input signal to pitch shifted signal sent to the output of the pitch shifter. More...

virtual UTF8String	getName () const
	Return a human-readable name for this pitch shifter. More...

virtual UTF8String	getManufacturer () const
	Return the manufacturer name of this pitch shifter. More...

virtual FilterVersion	getVersion () const
	Return an object representing the version of this pitch shifter. More...

virtual FilterCategory	getCategory () const
	Return an object that describes the category of effect that this filter implements. More...

virtual Time	getLatency () const
	Return a Time value indicating the latency of this pitch shifter in seconds. More...

virtual Size	getParameterCount () const
	Return the total number of generic accessible parameters this filter has. More...

virtual Bool	getParameterInfo (Index parameterIndex, FilterParameterInfo &info) const
	Get information about the filter parameter at the specified index. More...

Public Member Functions inherited from om::sound::filters::SoundFilter
virtual	~SoundFilter ()
	Destroy this sound filter object. More...

SoundResult	read (SoundBuffer &outputBuffer, Size numSamples)
	Fill the specified output buffer with the requested number of samples, based on internal filter state. More...

SoundResult	read (SoundFrame &outputFrame, Size numSamples)
	Fill the specified output frame with the requested number of samples, based on internal filter state. More...

SoundResult	write (const SoundBuffer &inputBuffer, Size numSamples)
	Process the specified input buffer samples and do something with them. More...

SoundResult	write (const SoundFrame &inputFrame, Size numSamples)
	Process the specified input frame samples and do something with them. More...

SoundResult	process (const SoundBuffer &inputBuffer, SoundBuffer &outputBuffer, Size numSamples)
	Apply this filter to the specified input buffer data, placing the result in the output buffer. More...

SoundResult	process (const SoundBuffer &inputBuffer, SoundFrame &outputFrame, Size numSamples)
	Apply this filter to the specified input buffer data, placing the result in the output frame. More...

SoundResult	process (const SoundFrame &inputFrame, SoundFrame &outputFrame, Size numSamples)
	Apply this filter to the specified input frame data, placing the result in the output frame. More...

SoundResult	process (const SoundFrame &inputBuffer, SoundBuffer &outputBuffer, Size numSamples)
	Apply this filter to the specified input frame data, placing the result in the output buffer. More...

void	reset ()
	Signal to the filter that the audio stream is restarting. More...

UInt64	getFrameIndex () const
	Return the index of the next frame to be processed (or the current one if currently processing). More...

Size	getInputCount () const
	Return the current number of audio inputs that this filter has. More...

virtual UTF8String	getInputName (Index inputIndex) const
	Return a human-readable name of the filter audio input at the specified index. More...

Size	getOutputCount () const
	Return the current number of audio outputs that this filter has. More...

virtual UTF8String	getOutputName (Index outputIndex) const
	Return a human-readable name of the filter audio output at the specified index. More...

Size	getMIDIInputCount () const
	Return the current number of MIDI inputs that this filter has. More...

virtual UTF8String	getMIDIInputName (Index inputIndex) const
	Return a human-readable name of the filter MIDI input at the specified index. More...

Size	getMIDIOutputCount () const
	Return the current number of MIDI outputs that this filter has. More...

virtual UTF8String	getMIDIOutputName (Index outputIndex) const
	Return a human-readable name of the filter MIDI output at the specified index. More...

virtual Bool	getParameterIndex (const UTF8String &parameterName, Index &parameterIndex) const
	Query the index of the parameter with the specified name. More...

virtual Bool	getParameterValueName (Index parameterIndex, const FilterParameter &value, UTF8String &name) const
	Get any special name associated with the specified value of an indexed parameter. More...

Bool	getParameter (Index parameterIndex, FilterParameter &value) const
	Place the value of the parameter at the specified index in the output parameter. More...

Bool	getParameter (Index parameterIndex, Bool &value) const
	Place the value of the parameter at the specified index in the output parameter. More...

Bool	getParameter (Index parameterIndex, Int64 &value) const
	Place the value of the parameter at the specified index in the output parameter. More...

Bool	getParameter (Index parameterIndex, Float32 &value) const
	Place the value of the parameter at the specified index in the output parameter. More...

Bool	getParameter (Index parameterIndex, Float64 &value) const
	Place the value of the parameter at the specified index in the output parameter. More...

template<typename ParameterType >
Bool	getParameter (const UTF8String &name, ParameterType &value) const
	Place the value of the parameter with the specified name in the output parameter. More...

template<typename ParameterType >
Bool	getParameter (const char *name, ParameterType &value) const
	Place the value of the parameter with the specified name in the output parameter. More...

Bool	setParameter (Index parameterIndex, const FilterParameter &value)
	Attempt to set the parameter value at the specified index. More...

Bool	setParameter (Index parameterIndex, Bool value)
	Attempt to set the parameter value at the specified index. More...

Bool	setParameter (Index parameterIndex, Int64 value)
	Attempt to set the parameter value at the specified index. More...

Bool	setParameter (Index parameterIndex, Float32 value)
	Attempt to set the parameter value at the specified index. More...

Bool	setParameter (Index parameterIndex, Float64 value)
	Attempt to set the parameter value at the specified index. More...

template<typename ParameterType >
Bool	setParameter (const UTF8String &name, ParameterType value)
	Attempt to set the parameter value with the specified name. More...

template<typename ParameterType >
Bool	setParameter (const char *name, ParameterType value)
	Attempt to set the parameter value with the specified name. More...

virtual Bool	writeState (DataOutputStream &stream) const
	Write the current state of this sound filter to a data output stream. More...

virtual Bool	readState (DataInputStream &stream)
	Read a previously saved filter state from the specified data input stream and replace the filter's state. More...

virtual Size	getPresetCount () const
	Return the number of standard configuration presets that this sound filter has. More...

virtual Bool	getPreset (Index presetIndex, FilterPreset &preset) const
	Get the standard preset for this sound filter with the specified index. More...

Bool	getIsSynchronized () const
	Return whether or not this sound filter performs thread synchronization. More...

void	setIsSynchronized (Bool newIsSynchronized)
	Set whether or not this sound filter performs thread synchronization. More...

virtual Bool	allowsInPlaceProcessing () const
	Return whether or not this sound filter can process audio data in-place. More...

Static Public Attributes
static const UTF8String	NAME
	A string indicating the human-readable name of this pitch shifter. More...

static const UTF8String	MANUFACTURER
	A string indicating the manufacturer name of this pitch shifter. More...

static const FilterVersion	VERSION
	An object indicating the version of this pitch shifter. More...

Static Public Attributes inherited from om::sound::filters::SoundFilter
static const om::resources::ResourceType	RESOURCE_TYPE
	The resource type for a sound filter. More...

Additional Inherited Members
Static Public Member Functions inherited from om::sound::filters::SoundFilter
static Size	getMaximumNumberOfInputs ()
	Return the maximum number of audio inputs that a SoundFilter can support. More...

static Size	getMaximumNumberOfOutputs ()
	Return the maximum number of audio outputs that a SoundFilter can support. More...

static Size	getMaximumNumberOfMIDIInputs ()
	Return the maximum number of MIDI inputs that a SoundFilter can support. More...

static Size	getMaximumNumberOfMIDIOutputs ()
	Return the maximum number of MIDI outputs that a SoundFilter can support. More...

Protected Member Functions inherited from om::sound::filters::SoundFilter
	SoundFilter ()
	Create a new sound filter with 1 audio input and output, and no MIDI inputs or outputs. More...

	SoundFilter (Size numInputs, Size numOutputs)
	Create a new sound filter with the specified number of audio inputs and outputs. More...

	SoundFilter (Size numInputs, Size numOutputs, Size numMIDIInputs, Size numMIDIOutputs)
	Create a new sound filter with the specified number of audio inputs and outputs. More...

void	setInputCount (Size newNumInputs)
	Set the number of inputs that this filter should have. More...

void	setOutputCount (Size newNumOutputs)
	Set the number of outputs that this filter should have. More...

void	setMIDIInputCount (Size newNumMIDIInputs)
	Set the number of MIDI inputs that this filter should have. More...

void	setMIDIOutputCount (Size newNumMIDIOutputs)
	Set the number of MIDI outputs that this filter should have. More...

Bool	isFirstFrame () const
	Return whether or not the filter's next frame to be processed is also its first frame. More...

void	lockMutex () const
	Acquire a mutex which handles subclass rendering parameter synchronization. More...

void	unlockMutex () const
	Release a mutex which handles subclass rendering parameter synchronization. More...

Detailed Description

A class that shifts the pitch of input audio up or down by a number of semitones.

This classes uses an oversampled DTFT to shift the pitch of input audio up or down.

The pitch shifter allows the user to set the FFT buffer size in seconds, controlling the approximate time-domain resolution of the effect. A larger buffer size produces better frequency resolution but less time resolution, resulting in transient smearing. A smaller buffer can produce frequency domain artifacts due to the limited frequency resolution, but will have better transient response. The buffer length also determines the approximate latency of the effect.

Additionally, the shifter allows the user to control the oversampling factor for the effect. A higher oversampling level produces better quality results but at an exponential increase in CPU time. Higher oversampling amounts also can increase the time-domain smearing of the effect.

Constructor & Destructor Documentation

om::sound::filters::PitchShifter::PitchShifter ( )

Create a new pitch shifter with no pitch shift.

om::sound::filters::PitchShifter::PitchShifter ( Float newSemitoneShift )

Create a new pitch shifter which shifts the input audio by the specified number of semitones.

Member Function Documentation

Float om::sound::filters::PitchShifter::getShift ( ) const

inline

Return the current pitch shift amount expressed as a frequency multiplier.

void om::sound::filters::PitchShifter::setShift ( Float newShift )

inline

Set the pitch shift amount, expressed as a frequency multiplier.

Float om::sound::filters::PitchShifter::getSemitoneShift ( ) const

inline

Return the current pitch shift amount in signed semitones.

void om::sound::filters::PitchShifter::setSemitoneShift ( Float newSemitones )

inline

Set the current pitch shift amount in signed semitones.

Float om::sound::filters::PitchShifter::getBufferLength ( ) const

inline

Return the length in seconds of the FFT buffer used when doing pitch shifting.

A longer buffer will result in higher frequency-domain resolution but decreased time-domain resolution. During rendering, since FFT buffers must have a power-of-two size, the next largest power of two is used for the buffer size, calculated based on the current sample rate and buffer length in seconds.

void om::sound::filters::PitchShifter::setBufferLength ( Float newBufferLength )

inline

Set the length in seconds of the FFT buffer used when doing pitch shifting.

A longer buffer will result in higher frequency-domain resolution but decreased time-domain resolution. During rendering, since FFT buffers must have a power-of-two size, the next largest power of two is used for the buffer size, calculated based on the current sample rate and buffer length in seconds.

The new buffer length is clamped to be greater than or equal to 0.

Size om::sound::filters::PitchShifter::getOversampling ( ) const

inline

Return the oversampling factor currently used by this pitch shifter.

This number indicates the number of FFT passes that the shifter makes over the input audio. The more passes, the better quality the resulting shifted audio will be. However, an oversampling factor N will require approximately 2^N times as much time to process the effect.

The default oversampling factor is 2.

void om::sound::filters::PitchShifter::setOversampling ( Size newOversampling )

inline

Set the oversampling factor currently used by this pitch shifter.

This number indicates the number of FFT passes that the shifter makes over the input audio. The more passes, the better quality the resulting shifted audio will be. However, an oversampling factor N will require approximately 2^N times as much time to process the effect.

The default oversampling factor is 2.

Gain om::sound::filters::PitchShifter::getMix ( ) const

inline

Return the ratio of input signal to pitch shifted signal sent to the output of the pitch shifter.

Valid mix values are in the range [0,1]. A mix value of 1 indicates that only the output of the pitch shifter should be heard at the output, while a value of 0 indicates that only the input of the pitch shifter should be heard at the output. A value of 0.5 indicates that both should be mixed together equally at -6dB.

void om::sound::filters::PitchShifter::setMix ( Gain newMix )

inline

Set the ratio of input signal to pitch shifted signal sent to the output of the pitch shifter.

Valid mix values are in the range [0,1]. A mix value of 1 indicates that only the output of the pitch shifter should be heard at the output, while a value of 0 indicates that only the input of the pitch shifter should be heard at the output. A value of 0.5 indicates that both should be mixed together equally at -6dB.

The new mix value is clamped to the valid range of [0,1].

virtual UTF8String om::sound::filters::PitchShifter::getName ( ) const

virtual

Return a human-readable name for this pitch shifter.

The method returns the string "Pitch Shifter".

Reimplemented from om::sound::filters::SoundFilter.

virtual UTF8String om::sound::filters::PitchShifter::getManufacturer ( ) const

virtual

Return the manufacturer name of this pitch shifter.

The method returns the string "Om Sound".

Reimplemented from om::sound::filters::SoundFilter.

virtual FilterVersion om::sound::filters::PitchShifter::getVersion ( ) const