A class that keeps sound from going above a limiting threshold. More...

#include <omSoundLimiter.h>

Inheritance diagram for om::sound::filters::Limiter:

Public Member Functions
	Limiter ()
	Create a new limiter with the default limiting parameters. More...

	Limiter (Gain threshold, Gain inputGain, Gain outputGain, Float release)
	Create a new limiter with the specified threshold. More...

Gain	getInputGain () const
	Return the current linear input gain factor of this limiter. More...

Gain	getInputGainDB () const
	Return the current input gain factor in decibels of this limiter. More...

void	setInputGain (Gain newInputGain)
	Set the target linear input gain for limiter. More...

void	setInputGainDB (Gain newDBInputGain)
	Set the target input gain in decibels for this limiter. More...

Gain	getOutputGain () const
	Return the current linear output gain factor of this limiter. More...

Gain	getOutputGainDB () const
	Return the current output gain factor in decibels of this limiter. More...

void	setOutputGain (Gain newOutputGain)
	Set the target linear output gain for this limiter. More...

void	setOutputGainDB (Gain newDBOutputGain)
	Set the target output gain in decibels for this limiter. More...

Gain	getThreshold () const
	Return the linear full-scale value above which the limiter applies gain reduction. More...

Gain	getThresholdDB () const
	Return the logarithmic full-scale value above which the limiter applies gain reduction. More...

void	setThreshold (Gain newThreshold)
	Set the linear full-scale value above which the limiter applies gain reduction. More...

void	setThresholdDB (Gain newThresholdDB)
	Set the logarithmic full-scale value above which the limiter applies gain reduction. More...

Gain	getKnee () const
	Return the knee radius of this limiter in decibels. More...

void	setKnee (Gain newKnee)
	Set the knee radius of this limiter in decibels. More...

Float	getAttack () const
	Return the attack of this limiter in seconds. More...

void	setAttack (Float newAttack)
	Set the attack of this limiter in seconds. More...

Float	getRelease () const
	Return the release of this limiter in seconds. More...

void	setRelease (Float newRelease)
	Set the release of this limiter in seconds. More...

Bool	getChannelsAreLinked () const
	Return whether or not all channels in the limiter are linked together. More...

void	setChannelsAreLinked (Bool newChannelsAreLinked)
	Set whether or not all channels in the limiter are linked together. More...

Bool	getSaturationIsEnabled () const
	Return whether or not output saturation is occurring for the limiter. More...

void	setSaturationIsEnabled (Bool newSaturationIsEnabled)
	Set whether or not output saturation should occur for the limiter. More...

Gain	getSaturationKnee () const
	Return the knee of the output clipping function, in decibels. More...

void	setSaturationKnee (Gain newSaturationKnee)
	Set the knee of the output clipping function, in decibels. More...

Gain	getGainReductionDB () const
	Return the current gain reduction of the limiter in decibels. More...

Gain	getGainReduction () const
	Return the current gain reduction of the limiter on a linear scale. More...

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

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

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

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

virtual Bool	allowsInPlaceProcessing () const
	Return whether or not this limiter can process audio data in-place. 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 Time	getLatency () const
	Return a Time value indicating the latency of this sound filter in seconds. 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...

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

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

static const FilterVersion	VERSION
	An object indicating the version of this limiter. 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 keeps sound from going above a limiting threshold.

Constructor & Destructor Documentation

om::sound::filters::Limiter::Limiter ( )

Create a new limiter with the default limiting parameters.

These are - threshold: 0dB, release: 5ms, input gain: 0dB, output gain: 0dB, with unlinked channels.

om::sound::filters::Limiter::Limiter	(	Gain	threshold,
		Gain	inputGain,
		Gain	outputGain,
		Float	release
	)

Create a new limiter with the specified threshold.

The other limiting parameters are - release: 5ms, input gain: 0dB, output gain: 0dB, with unlinked channels.

Member Function Documentation

Gain om::sound::filters::Limiter::getInputGain ( ) const

inline

Return the current linear input gain factor of this limiter.

This is the gain applied to the input signal before being sent to the limiter. This allows the user to scale the input to match the limiter without having to change the limiter threshold.

Gain om::sound::filters::Limiter::getInputGainDB ( ) const

inline

Return the current input gain factor in decibels of this limiter.

This is the gain applied to the input signal before being sent to the limiter. This allows the user to scale the input to match the limiter without having to change the limiter threshold.

void om::sound::filters::Limiter::setInputGain ( Gain newInputGain )

inline

Set the target linear input gain for limiter.

This is the gain applied to the input signal before being sent to the limiter. This allows the user to scale the input to match the limiter without having to change the limiter threshold.

void om::sound::filters::Limiter::setInputGainDB ( Gain newDBInputGain )

inline

Set the target input gain in decibels for this limiter.

This is the gain applied to the input signal before being sent to the limiter. This allows the user to scale the input to match the limiter without having to change the limiter threshold.

Gain om::sound::filters::Limiter::getOutputGain ( ) const

inline

Return the current linear output gain factor of this limiter.

This is the gain applied to the signal after being sent to the limiter. This value is used to apply make-up gain to the signal after is has been compressed.

Gain om::sound::filters::Limiter::getOutputGainDB ( ) const

inline

Return the current output gain factor in decibels of this limiter.

This is the gain applied to the signal after being sent to the limiter. This value is used to apply make-up gain to the signal after is has been compressed.

void om::sound::filters::Limiter::setOutputGain ( Gain newOutputGain )

inline

Set the target linear output gain for this limiter.

This is the gain applied to the signal after being sent to the limiter. This value is used to apply make-up gain to the signal after is has been compressed.

void om::sound::filters::Limiter::setOutputGainDB ( Gain newDBOutputGain )

inline

Set the target output gain in decibels for this limiter.

This is the gain applied to the signal after being sent to the limiter. This value is used to apply make-up gain to the signal after is has been compressed.

Gain om::sound::filters::Limiter::getThreshold ( ) const

inline

Return the linear full-scale value above which the limiter applies gain reduction.

Gain om::sound::filters::Limiter::getThresholdDB ( ) const

inline

Return the logarithmic full-scale value above which the limiter applies gain reduction.

void om::sound::filters::Limiter::setThreshold ( Gain newThreshold )

inline

Set the linear full-scale value above which the limiter applies gain reduction.

The value is clamped to the valid range of [0,infinity] before being stored.

void om::sound::filters::Limiter::setThresholdDB ( Gain newThresholdDB )

inline

Set the logarithmic full-scale value above which the limiter applies gain reduction.

Gain om::sound::filters::Limiter::getKnee ( ) const

inline

Return the knee radius of this limiter in decibels.

This is the amount below the limiter's threshold at which the limiter first starts limiting. A higher knee will result in a limiter that starts to apply gain reduction to envelopes that approach the threshold, resulting in a smoother transition from no gain reduction to full gain reduction.

void om::sound::filters::Limiter::setKnee ( Gain newKnee )

inline

Set the knee radius of this limiter in decibels.

This is the amount below the limiter's threshold at which the limiter first starts limiting. A higher knee will result in a limiter that starts to apply gain reduction to envelopes that approach the threshold, resulting in a smoother transition from no gain reduction to full gain reduction.

The new knee value is clamped to the valid range of [0,+infinity].

Float om::sound::filters::Limiter::getAttack ( ) const

inline

Return the attack of this limiter in seconds.

This value indicates the time in seconds that it takes for the limiter's detection envelope to respond to a sudden increase in signal level. Thus, a very small attack softens transients more than a slower attack which lets the transients through the limiter.

void om::sound::filters::Limiter::setAttack ( Float newAttack )

inline

Set the attack of this limiter in seconds.

This value indicates the time in seconds that it takes for the limiter's detection envelope to respond to a sudden increase in signal level. Thus, a very small attack softens transients more than a slower attack which lets the transients through the limiter.

The new attack value is clamped to the range of [0,+infinity].

Float om::sound::filters::Limiter::getRelease ( ) const

inline

Return the release of this limiter in seconds.

This value indicates the time in seconds that it takes for the limiter's detection envelope to respond to a sudden decrease in signal level. Thus, a very short release doesn't compress the signal after a transient for as long as a longer release. Beware, very short release times (< 5ms) can result in audible distortion.

void om::sound::filters::Limiter::setRelease ( Float newRelease )

inline

Set the release of this limiter in seconds.

This value indicates the time in seconds that it takes for the limiter's detection envelope to respond to a sudden decrease in signal level. Thus, a very short release doesn't limit the signal after a transient for as long as a longer release. Beware, very short release times (< 5ms) can result in audible distortion.

The new release value is clamped to the valid range of [0,+infinity].

Bool om::sound::filters::Limiter::getChannelsAreLinked ( ) const

inline

Return whether or not all channels in the limiter are linked together.

If the value is TRUE, all channels are limited by the maximum limiting amount selected from all channel envelopes. This allows the limiter to maintain the stereo image of the audio when limiting hard-panned sounds.

void om::sound::filters::Limiter::setChannelsAreLinked ( Bool newChannelsAreLinked )

inline

Set whether or not all channels in the limiter are linked together.

If the value is TRUE, all channels are limited by the maximum limiting amount selected from all channel envelopes. This allows the limiter to maintain the stereo image of the audio when limiting hard-panned sounds.

Bool om::sound::filters::Limiter::getSaturationIsEnabled ( ) const

inline

Return whether or not output saturation is occurring for the limiter.

If this value is TRUE, a soft clipping function is applied to the output of the limiter which guarantees that the output signal will never exceed the threshold. This output saturation is usually used in combination with a slower attack to keep fast transients from going over the threshold while keeping the cleaner sound of a slow attack.

void om::sound::filters::Limiter::setSaturationIsEnabled ( Bool newSaturationIsEnabled )

inline

Set whether or not output saturation should occur for the limiter.

If this value is TRUE, a soft clipping function is applied to the output of the limiter which guarantees that the output signal will never exceed the threshold. This output saturation is usually used in combination with a slower attack to keep fast transients from going over the threshold while keeping the cleaner sound of a slow attack.

Gain om::sound::filters::Limiter::getSaturationKnee ( ) const

inline

Return the knee of the output clipping function, in decibels.

This is the number of decibels below the threshold where the transition from no saturation to saturation will occurr. A higher knee value indicates softer output clipping.

void om::sound::filters::Limiter::setSaturationKnee ( Gain newSaturationKnee )

inline

Set the knee of the output clipping function, in decibels.

This is the number of decibels below the threshold where the transition from no saturation to saturation will occurr. A higher knee value indicates softer output clipping.

The new knee value is clamped to the valid range of [0.01,+infinity].

Gain om::sound::filters::Limiter::getGainReductionDB ( ) const

inline

Return the current gain reduction of the limiter in decibels.

This value can be used as a way for humans to visualize how much the limiter is compressing at any given time.

Gain om::sound::filters::Limiter::getGainReduction ( ) const

inline

Return the current gain reduction of the limiter on a linear scale.

This value can be used as a way for humans to visualize how much the limiter is compressing at any given time.

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

virtual

Return a human-readable name for this limiter.

The method returns the string "Compressor".

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

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

virtual

Return the manufacturer name of this limiter.

The method returns the string "Om Sound".

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

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

virtual

Return an object representing the version of this limiter.

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

virtual FilterCategory om::sound::filters::Limiter::getCategory ( ) const

virtual

Return an object that describes the category of effect that this filter implements.

This method returns the value FilterCategory::DYNAMICS.

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

virtual Bool om::sound::filters::Limiter::allowsInPlaceProcessing ( ) const

virtual

Return whether or not this limiter can process audio data in-place.

This method always returns TRUE, limiters can process audio data in-place.

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

virtual Size om::sound::filters::Limiter::getParameterCount ( ) const

virtual

Return the total number of generic accessible parameters this filter has.

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

virtual Bool om::sound::filters::Limiter::getParameterInfo	(	Index	parameterIndex,
		FilterParameterInfo &	info
	)		const

virtual

Get information about the filter parameter at the specified index.

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

Member Data Documentation

const UTF8String om::sound::filters::Limiter::NAME

static

A string indicating the human-readable name of this limiter.

const UTF8String om::sound::filters::Limiter::MANUFACTURER

static

A string indicating the manufacturer name of this limiter.

const FilterVersion om::sound::filters::Limiter::VERSION

static

An object indicating the version of this limiter.

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

omSoundLimiter.h

Public Member Functions

Static Public Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation