The simplest of lowpass filters: a single-pole, no-zero algorithm. More...

#include <TTOnePole.h>

Inheritance diagram for TTOnePole:

Collaboration diagram for TTOnePole:

Protected Member Functions
TTErr	updateMaxNumChannels (const TTValue &oldMaxNumChannels, TTValue &)
	Receives notifications when there are changes to the inherited mMaxNumChannels attribute. More...

TTErr	updateSampleRate (const TTValue &oldSampleRate, TTValue &)
	Receives notifications when there are changes to the inherited sr attribute. More...

TTErr	clear ()
	This algorithm uses an IIR filter, meaning that it relies on feedback. More...

TTErr	setMode (const TTValue &value)
	Setter for the mode attribute. More...

TTErr	setFrequency (const TTValue &value)
	Setter for the frequency attribute. More...

virtual TTErr	test (TTValue &returnedTestInfo)
	Unit Tests. More...

Protected Member Functions inherited from TTAudioObjectBase
TTErr	setProcess (TTProcessMethod processMethod)
	Set the audio processing routine to point to a method that is defined as an arg to this function. More...

TTErr	setCalculate (TTCalculateMethod newCalculateMethod)
	Set the sample calculate routine to point to a method that is defined as an arg to this function. More...

TTErr	setBypass (const TTValue &value)
	Bypass the audio processing routine and copy all input samples to the output unchanged. More...

TTErr	resetBenchmarking ()
	Reset the benchmarking accumulation used to calculate the results of getProcessingBenchmark(). More...

TTErr	getProcessingBenchmark (TTValueConstRef, TTValueRef v)
	Return the average time spent by this object processing audio since the last reset. More...

	TTAudioObjectBase (const TTValue &arguments)
	Constructor. More...

Protected Member Functions inherited from TTObjectBase
	TTObjectBase (const TTValue arguments)
	Constructor. More...

Protected Attributes
TTSymbol	mMode
	filter mode: 'lowpass' or 'highpass'

TTFloat64	mFrequency
	filter cutoff frequency

TTFloat64	mLowpassCoefficient
	filter coefficients

TTFloat64	mOneMinusLowpassCoefficient
	filter coefficients

TTFloat64	mHighpassCoefficient
	filter coefficients

TTFloat64	mOneMinusHighpassCoefficient
	filter coefficients

TTSampleVector	mFeedback
	previous output sample for each channel

Protected Attributes inherited from TTAudioObjectBase
TTUInt32	sr
	Current sample rate being used by this object.

TTFloat64	srInv
	1.0 over the current sample rate (inverse)

TTFloat64	srMill
	1/1000 of the current sample rate (samples per millisecond)

TTChannelCount	mMaxNumChannels
	This is the maximum number of channels that can be guaranteed to work.

TTBoolean	unused
	Old var that is not used anymore, but we want to keep the struct size the same.

TTBoolean	attrBypass
	Are we bypassing the processMethod?

TTBoolean	attrMute
	Mute the processMethod.

TTProcessMethod	processMethod
	This function pointer points to the active (non-bypass) processing routine.

TTProcessMethod	currentProcessMethod
	This function pointer always points to the current processing routine.

TTCalculateMethod	calculateMethod
	This function pointer points to the active (non-bypass) calculate routine.

TTCalculateMethod	currentCalculateMethod
	This function pointer always points to the current calculate routine.

TTObject	inputArray
	If the process method is passed a signal, rather than an array of signals, we wrap the signal in this array.

TTObject	outputArray
	If the process method is passed a signal, rather than an array of signals, we wrap the signal in this array.

TTFloat64	startProcessingTime
	The time at which this object's process method was last invoked (for benchmarking)

TTFloat64	accumulatedProcessingTime
	The amount of time spent in this object's process method (for benchmarking)

TTFloat64	accumulatedProcessingCalls
	The number of times the process method has been called (for benchmarking)

Protected Attributes inherited from TTObjectBase
TTList	observers
	List of all objects watching this object for life-cycle and other changes.

Additional Inherited Members
Public Member Functions inherited from TTAudioObjectBase
TTErr	setMute (const TTValue &value)
	Mute the audio processing routine and zero all output. More...

TTErr	setMaxNumChannels (const TTValue &newValue)
	Setter for the maxNumChannels attribute. More...

TTErr	adaptMaxNumChannels (const TTChannelCount newMaxNumChannels)
	Increase the maxNumChannels attribute, if neccessary. More...

TTErr	setSr (const TTValue &newValue)
	Setter for the sample-rate attribute. More...

TTErr	setSampleRate (const TTUInt32 &newSampleRate)
	Convenience method for updating the sample-rate. More...

virtual	~TTAudioObjectBase ()
	Destructor.

TTErr	calculate (const TTFloat64 &x, TTFloat64 &y)
	Calculate a single sample of output for a single sample of input. More...

TTErr	calculateMessage (TTValueConstRef input, TTValueRef output)

TTErr	process (TTAudioSignal &in, TTAudioSignal &out)
	Process the input signal, resulting in an output signal. More...

TTErr	process (TTAudioSignal &out)
	Process the an output signal only, e.g. More...

TTErr	process (TTAudioSignal &in1, TTAudioSignal &in2, TTAudioSignal &out1, TTAudioSignal &out2)
	Process two input signals, resulting in two output signals. More...

TTErr	process (TTAudioSignal &in1, TTAudioSignal &in2, TTAudioSignal &out)
	Process two input signals, resulting in an output signal. More...

TTErr	process (TTAudioSignalArrayPtr inputs, TTAudioSignalArrayPtr outputs)
	Process an array of audio signals. More...

TTErr	bypassProcess (TTAudioSignalArrayPtr inputs, TTAudioSignalArrayPtr outputs)
	The default audio processing method, which simply copies a signal through with no modifications. More...

TTErr	bypassCalculate (const TTFloat64 &x, TTFloat64 &y, TTPtr data)
	Produces a result for calls to calculate when the unit is bypassed. More...

TTErr	muteProcess (TTAudioSignalArrayPtr inputs, TTAudioSignalArrayPtr outputs)
	A muted audio processing method, which simply copies zeroes to the output. More...

TTErr	defaultCalculateMethod (const TTFloat64 &x, TTFloat64 &y, TTPtr data)
	A default calculate method, which simply calls the process method with 1 channel signals that are 1 sample in length. More...

TTFloat64	hertzToRadians (const TTFloat64 hz)
	Convert Hertz to radians. More...

TTFloat64	radiansToHertz (const TTFloat64 radians)
	Convert radians into Hertz. More...

TTFloat64	degreesToRadians (const TTFloat64 degrees)
	Degrees-to-radians conversion. More...

TTFloat64	radiansToDegrees (const TTFloat64 radians)
	Radians-to-degrees conversion. More...

TTFloat64	decayToFeedback (const TTFloat64 decay_time, TTFloat64 delay)
	Decay Time (seconds) to feedback coefficient conversion. More...

TTFloat64	feedbackToDecay (const TTFloat64 feedback, const TTFloat64 delay)
	Return the decay time based on the feedback coefficient. More...

Public Member Functions inherited from TTObjectBase
virtual	~TTObjectBase ()
	Destructor.

TTUInt16	getReferenceCount ()
	Query an object to get its current reference count. More...

TTUInt32	getObserverCount () const
	Query an object to get the number of observers. More...

TTErr	registerAttribute (const TTSymbol name, const TTDataType type, void *address)
	Register an attribute. More...

TTErr	extendAttribute (const TTSymbol name, const TTObjectBasePtr extendedObject, const TTSymbol extendedName)
	Extend the attribute of an existing TTObjectBase to this TTObjectBase (using another attribute name) More...

TTErr	removeAttribute (const TTSymbol name)
	Remove an attribute. More...

TTErr	findAttribute (const TTSymbol name, TTAttribute **attr)
	Find an attribute. More...

TTErr	setAttributeValue (const TTSymbol name, TTValue &value)
	Set an attribute value for an object. More...

template<class T >
TTErr	set (const TTSymbol aName, T aValue)
	Set an attribute value for an object This is the same as calling setAttributeValue(). More...

TTErr	getAttributeValue (const TTSymbol name, TTValue &value)
	Get an attribute value for an object. More...

template<class T >
TTErr	get (const TTSymbol aName, T &aReturnedValue)
	Get an attribute value for an object This is the same as calling getAttributeValue(). More...

TTSymbol	getAttributeType (const TTSymbol name)
	Return the type of an attribute as a symbol. More...

TTErr	getAttributeGetterFlags (const TTSymbol name, TTAttributeFlags &value)
	Get the getterFlags of an attribute. More...

TTErr	setAttributeGetterFlags (const TTSymbol name, TTAttributeFlags &value)
	Set the getterFlags of an attribute. More...

TTErr	getAttributeSetterFlags (const TTSymbol name, TTAttributeFlags &value)
	Get the setterFlags of an attribute. More...

TTErr	setAttributeSetterFlags (const TTSymbol name, TTAttributeFlags &value)
	Set the setterFlags of an attribute. More...

TTErr	registerAttributeProperty (const TTSymbol attributeName, const TTSymbol propertyName, const TTValue &initialValue, TTGetterMethod getter, TTSetterMethod setter)
	Register an attribute property. More...

TTErr	registerMessageProperty (const TTSymbol messageName, const TTSymbol propertyName, const TTValue &initialValue, TTGetterMethod getter, TTSetterMethod setter)
	Register an message property. More...

TTErr	getAttribute (const TTSymbol name, TTAttributePtr *attributeObject)
	Search for and locate an attribute. More...

TTErr	getMessage (const TTSymbol name, TTMessagePtr *messageObject)
	Search for and locate a message. More...

void	getAttributeNames (TTValue &attributeNameList)
	Return a list of names of the available attributes. More...

void	getMessageNames (TTValue &messageNameList)
	Return a list of names of the available messages. More...

TTSymbol	getName () const
	Return the name of this class. More...

TTErr	registerMessage (const TTSymbol name, TTMethod method)
	Register a message with this object. More...

TTErr	findMessage (const TTSymbol name, TTMessage **message)
	Find a message registered with this object. More...

TTErr	removeMessage (const TTSymbol name)
	Remove a message. More...

TTErr	sendMessage (const TTSymbol name)
	TODO: Document this function. More...

TTErr	registerObserverForMessage (const TTObject &observingObject, const TTSymbol messageName)
	Register an observer for a message. More...

TTErr	registerObserverForAttribute (const TTObject &observingObject, const TTSymbol attributeName)
	Register an observer for an attribute. More...

TTErr	registerObserverForNotifications (const TTObject &observingObject)
	Register an observer. More...

TTErr	unregisterObserverForMessage (const TTObject &observingObject, const TTSymbol messageName)
	Unregister an observer for a message. More...

TTErr	unregisterObserverForAttribute (const TTObject &observingObject, const TTSymbol attributeName)
	Unregister an observer for an attribute. More...

TTErr	unregisterObserverForNotifications (const TTObject &observingObject)
	Unregister an observer for notifications. More...

TTErr	sendNotification (const TTSymbol name, const TTValue &arguments)
	Send a notification. More...

TTErr	logMessage (TTImmutableCString fmtstring,...)
	Log messages scoped to this object instance. More...

TTErr	logWarning (TTImmutableCString fmtstring,...)
	Log warnings scoped to this object instance. More...

TTErr	logError (TTImmutableCString fmtstring,...)
	Log errors scoped to this object instance. More...

TTErr	logDebug (TTImmutableCString fmtstring,...)
	Log messages (scoped to this object instance) to output only if the basic debugging flag is enabled in the environment. More...

TTErr	lock ()
	Lock the object in order to ensure thread-safe processing. More...

TTErr	unlock ()
	Unlock the object when thread-safe processing is no longer required. More...

TTBoolean	isLocked ()
	Query if the object currently is locked for thread-safe processing. More...

TTBoolean	waitForLock ()
	If the object is locked (e.g. More...

Public Attributes inherited from TTObjectBase
TTBoolean	valid
	If the object isn't completely built, or is in the process of freeing, this will be false.

TTBoolean	track
	enable the print of a log message to ease the track of reference counting mechanism on an instance More...

Detailed Description

The simplest of lowpass filters: a single-pole, no-zero algorithm.

Definition at line 24 of file TTOnePole.h.

Member Function Documentation

TTErr TTOnePole::clear ( )

protected

This algorithm uses an IIR filter, meaning that it relies on feedback.

If the filter should not be producing any signal (such as turning audio off and then back on in a host) or if the feedback has become corrupted (such as might happen if a NaN is fed in) then it may be neccesary to clear the filter by calling this method.