A two-pass effect to reduce background noise. More...

#include <NoiseReduction.h>

Inheritance diagram for EffectNoiseReduction:

Collaboration diagram for EffectNoiseReduction:

Classes
class	Dialog
	Dialog used with EffectNoiseReduction. More...

class	Settings

class	Statistics

class	Worker

Public Member Functions
	EffectNoiseReduction ()

virtual	~EffectNoiseReduction ()

ComponentInterfaceSymbol	GetSymbol () const override

TranslatableString	GetDescription () const override

EffectType	GetType () const override
	Type determines how it behaves. More...

int	ShowHostInterface (wxWindow &parent, const EffectDialogFactory &factory, std::shared_ptr< EffectInstance > &pInstance, EffectSettingsAccess &access, bool forceModal=false) override

bool	Process (EffectInstance &instance, EffectSettings &settings) override
	Actually do the effect here. More...

bool	TrackProgress (int whichTrack, double frac, const TranslatableString &={}) const

Public Member Functions inherited from StatefulEffect
std::shared_ptr< EffectInstance >	MakeInstance () const override
	Make an object maintaining short-term state of an Effect. More...

Public Member Functions inherited from StatefulEffectBase
virtual bool	Init ()
	Call once to set up state for whole list of tracks to be processed. More...

virtual bool	Process (EffectInstance &instance, EffectSettings &settings)=0
	Actually do the effect here. More...

virtual bool	RealtimeInitialize (EffectSettings &settings, double sampleRate)

virtual bool	RealtimeAddProcessor (EffectSettings &settings, unsigned numChannels, float sampleRate)

virtual bool	RealtimeSuspend ()

virtual bool	RealtimeResume ()

virtual bool	RealtimeProcessStart (EffectSettings &settings)
	settings are possibly changed, since last call, by an asynchronous dialog More...

virtual size_t	RealtimeProcess (size_t group, EffectSettings &settings, const float const inBuf, float const outBuf, size_t numSamples)

virtual bool	RealtimeProcessEnd (EffectSettings &settings) noexcept
	settings can be updated to let a dialog change appearance at idle More...

virtual bool	RealtimeFinalize (EffectSettings &settings) noexcept

virtual size_t	SetBlockSize (size_t maxBlockSize)

virtual size_t	GetBlockSize () const

Public Member Functions inherited from Effect
	Effect ()

virtual	~Effect ()

PluginPath	GetPath () const override

bool	VisitSettings (SettingsVisitor &visitor, EffectSettings &settings) override

bool	VisitSettings (ConstSettingsVisitor &visitor, const EffectSettings &settings) const override

ComponentInterfaceSymbol	GetSymbol () const override

VendorSymbol	GetVendor () const override

wxString	GetVersion () const override

TranslatableString	GetDescription () const override

EffectType	GetType () const override
	Type determines how it behaves. More...

EffectFamilySymbol	GetFamily () const override
	Report identifier and user-visible name of the effect protocol. More...

bool	IsInteractive () const override
	Whether the effect needs a dialog for entry of settings. More...

bool	IsDefault () const override
	Whether the effect sorts "above the line" in the menus. More...

RealtimeSince	RealtimeSupport () const override
	Since which version of Audacity has the effect supported realtime? More...

bool	SupportsAutomation () const override
	Whether the effect has any automatable controls. More...

bool	SaveSettings (const EffectSettings &settings, CommandParameters &parms) const override
	Store settings as keys and values. More...

bool	LoadSettings (const CommandParameters &parms, EffectSettings &settings) const override
	Restore settings from keys and values. More...

bool	LoadUserPreset (const RegistryPath &name, EffectSettings &settings) const override
	Change settings to a user-named preset. More...

bool	SaveUserPreset (const RegistryPath &name, const EffectSettings &settings) const override
	Save settings in the configuration file as a user-named preset. More...

RegistryPaths	GetFactoryPresets () const override
	Report names of factory presets. More...

bool	LoadFactoryPreset (int id, EffectSettings &settings) const override
	Change settings to the preset whose name is `GetFactoryPresets()[id]` More...

bool	LoadFactoryDefaults (EffectSettings &settings) const override
	Change settings back to "factory default". More...

unsigned	GetAudioInCount () const override
	How many input buffers to allocate at once. More...

unsigned	GetAudioOutCount () const override
	How many output buffers to allocate at once. More...

virtual const EffectParameterMethods &	Parameters () const

int	ShowClientInterface (wxWindow &parent, wxDialog &dialog, bool forceModal=false) override

std::unique_ptr< EffectUIValidator >	PopulateUI (ShuttleGui &S, EffectInstance &instance, EffectSettingsAccess &access) override
	Adds controls to a panel that is given as the parent window of `S` More...

bool	IsGraphicalUI () override

bool	ValidateUI (EffectSettings &) override

bool	CloseUI () override

bool	CanExportPresets () override

void	ExportPresets (const EffectSettings &settings) const override

void	ImportPresets (EffectSettings &settings) override

bool	HasOptions () override

void	ShowOptions () override

const EffectSettingsManager &	GetDefinition () const override

virtual NumericFormatSymbol	GetSelectionFormat ()

int	ShowHostInterface (wxWindow &parent, const EffectDialogFactory &factory, std::shared_ptr< EffectInstance > &pInstance, EffectSettingsAccess &access, bool forceModal=false) override
	Usually applies factory to self and given access. More...

bool	SaveSettingsAsString (const EffectSettings &settings, wxString &parms) const override

bool	LoadSettingsFromString (const wxString &parms, EffectSettings &settings) const override

bool	IsBatchProcessing () const override

void	SetBatchProcessing () override

void	UnsetBatchProcessing () override

bool	TransferDataToWindow (const EffectSettings &settings) override
	Update controls for the settings. More...

bool	TransferDataFromWindow (EffectSettings &settings) override
	Update the given settings from controls. More...

unsigned	TestUIFlags (unsigned mask)

bool	Delegate (Effect &delegate, EffectSettings &settings)
	Re-invoke DoEffect on another Effect object that implements the work. More...

int	MessageBox (const TranslatableString &message, long style=DefaultMessageBoxStyle, const TranslatableString &titleStr={}) const

bool	EnableApply (bool enable=true)

wxWindow *	GetUIParent ()

Public Member Functions inherited from EffectBase
	EffectBase ()

	~EffectBase () override

Public Member Functions inherited from EffectUIClientInterface
virtual	~EffectUIClientInterface ()

virtual int	ShowClientInterface (wxWindow &parent, wxDialog &dialog, bool forceModal=false)=0

virtual bool	IsGraphicalUI ()=0

virtual std::unique_ptr< EffectUIValidator >	PopulateUI (ShuttleGui &S, EffectInstance &instance, EffectSettingsAccess &access)=0
	Adds controls to a panel that is given as the parent window of `S` More...

virtual bool	CanExportPresets ()=0

virtual void	ExportPresets (const EffectSettings &settings) const =0

virtual void	ImportPresets (EffectSettings &settings)=0

virtual bool	HasOptions ()=0

virtual void	ShowOptions ()=0

Public Member Functions inherited from EffectPlugin
EffectPlugin &	operator= (EffectPlugin &)=delete

virtual	~EffectPlugin ()

virtual const EffectSettingsManager &	GetDefinition () const =0

virtual int	ShowHostInterface (wxWindow &parent, const EffectDialogFactory &factory, std::shared_ptr< EffectInstance > &pInstance, EffectSettingsAccess &access, bool forceModal=false)=0
	Usually applies factory to self and given access. More...

virtual void	Preview (EffectSettingsAccess &access, bool dryOnly)=0

virtual bool	SaveSettingsAsString (const EffectSettings &settings, wxString &parms) const =0

virtual bool	LoadSettingsFromString (const wxString &parms, EffectSettings &settings) const =0

virtual bool	IsBatchProcessing () const =0

virtual void	SetBatchProcessing ()=0

virtual void	UnsetBatchProcessing ()=0

virtual bool	DoEffect (EffectSettings &settings, double projectRate, TrackList list, WaveTrackFactory factory, NotifyingSelectedRegion &selectedRegion, unsigned flags, wxWindow *pParent=nullptr, const EffectDialogFactory &dialogFactory={}, const EffectSettingsAccessPtr &pAccess=nullptr)=0
	Unfortunately complicated dual-use function. More...

virtual bool	TransferDataToWindow (const EffectSettings &settings)=0
	Update controls for the settings. More...

virtual bool	TransferDataFromWindow (EffectSettings &settings)=0
	Update the given settings from controls. More...

Public Member Functions inherited from EffectInstanceFactory
virtual	~EffectInstanceFactory ()

virtual std::shared_ptr< EffectInstance >	MakeInstance () const =0
	Make an object maintaining short-term state of an Effect. More...

virtual unsigned	GetAudioInCount () const =0
	How many input buffers to allocate at once. More...

virtual unsigned	GetAudioOutCount () const =0
	How many output buffers to allocate at once. More...

virtual int	GetMidiInCount () const
	Function that has not yet found a use. More...

virtual int	GetMidiOutCount () const
	Function that has not yet found a use. More...

Public Member Functions inherited from EffectSettingsManager
virtual	~EffectSettingsManager ()

virtual bool	VisitSettings (SettingsVisitor &visitor, EffectSettings &settings)

virtual bool	VisitSettings (ConstSettingsVisitor &visitor, const EffectSettings &settings) const

virtual EffectSettings	MakeSettings () const

virtual bool	CopySettingsContents (const EffectSettings &src, EffectSettings &dst) const
	Update one settings object from another. More...

Public Member Functions inherited from EffectDefinitionInterface
virtual	~EffectDefinitionInterface ()

virtual EffectType	GetType () const =0
	Type determines how it behaves. More...

virtual EffectType	GetClassification () const
	Determines which menu it appears in; default same as GetType(). More...

virtual EffectFamilySymbol	GetFamily () const =0
	Report identifier and user-visible name of the effect protocol. More...

virtual bool	IsInteractive () const =0
	Whether the effect needs a dialog for entry of settings. More...

virtual bool	IsDefault () const =0
	Whether the effect sorts "above the line" in the menus. More...

virtual RealtimeSince	RealtimeSupport () const =0
	Since which version of Audacity has the effect supported realtime? More...

bool	SupportsRealtime () const

virtual bool	SupportsAutomation () const =0
	Whether the effect has any automatable controls. More...

virtual bool	EnablesDebug () const
	Whether the effect dialog should have a Debug button; default, always false. More...

virtual ManualPageID	ManualPage () const
	Name of a page in the Audacity alpha manual, default is empty. More...

virtual FilePath	HelpPage () const
	Fully qualified local help file name, default is empty. More...

virtual bool	IsHiddenFromMenus () const
	Default is false. More...

Public Member Functions inherited from ComponentInterface
virtual	~ComponentInterface ()

virtual PluginPath	GetPath () const =0

virtual ComponentInterfaceSymbol	GetSymbol () const =0

virtual VendorSymbol	GetVendor () const =0

virtual wxString	GetVersion () const =0

virtual TranslatableString	GetDescription () const =0

TranslatableString	GetName () const

Static Public Attributes
static const ComponentInterfaceSymbol	Symbol { XO("Noise Reduction") }

Static Public Attributes inherited from EffectPlugin
static const wxString	kUserPresetIdent = wxT("User Preset:")

static const wxString	kFactoryPresetIdent = wxT("Factory Preset:")

static const wxString	kCurrentSettingsIdent = wxT("<Current Settings>")

static const wxString	kFactoryDefaultsIdent = wxT("<Factory Defaults>")

Private Attributes
std::unique_ptr< Settings >	mSettings

std::unique_ptr< Statistics >	mStatistics

Friends
class	Dialog

Additional Inherited Members
Public Types inherited from Effect
enum	: long { DefaultMessageBoxStyle = wxOK \| wxCENTRE }

Public Types inherited from EffectPlugin
using	EffectSettingsAccessPtr = std::shared_ptr< EffectSettingsAccess >

Public Types inherited from EffectDefinitionInterface
enum class	RealtimeSince : unsigned { Never , Since_3_2 , Always }
	In which versions of Audacity was an effect realtime capable? More...

Static Public Member Functions inherited from Effect
static Effect *	FetchParameters (Effect &e, EffectSettings &)

static void	IncEffectCounter ()

Static Public Member Functions inherited from EffectDefinitionInterface
static Identifier	GetSquashedName (const Identifier &ident)
	A utility that strips spaces and CamelCases a name. More...

Protected Member Functions inherited from Effect
bool	EnablePreview (bool enable=true)

bool	CheckWhetherSkipEffect (const EffectSettings &settings) const override
	Default implementation returns false. More...

double	CalcPreviewInputLength (const EffectSettings &settings, double previewLength) const override
	Default implementation returns `previewLength` More...

virtual std::unique_ptr< EffectUIValidator >	PopulateOrExchange (ShuttleGui &S, EffectInstance &instance, EffectSettingsAccess &access)
	Add controls to effect panel; always succeeds. More...

bool	TotalProgress (double frac, const TranslatableString &={}) const

bool	TrackProgress (int whichTrack, double frac, const TranslatableString &={}) const

bool	TrackGroupProgress (int whichGroup, double frac, const TranslatableString &={}) const

int	GetNumWaveTracks () const

int	GetNumWaveGroups () const

void	GetBounds (const WaveTrack &track, const WaveTrack pRight, sampleCount start, sampleCount *len)

void	CopyInputTracks (bool allSyncLockSelected=false)

std::shared_ptr< AddedAnalysisTrack >	AddAnalysisTrack (const wxString &name=wxString())

ModifiedAnalysisTrack	ModifyAnalysisTrack (const LabelTrack *pOrigTrack, const wxString &name=wxString())

Track *	AddToOutputTracks (const std::shared_ptr< Track > &t)

Protected Member Functions inherited from EffectBase
void	Preview (EffectSettingsAccess &access, bool dryOnly) override

bool	DoEffect (EffectSettings &settings, double projectRate, TrackList list, WaveTrackFactory factory, NotifyingSelectedRegion &selectedRegion, unsigned flags, wxWindow *pParent, const EffectDialogFactory &dialogFactory, const EffectSettingsAccessPtr &pAccess) override
	Unfortunately complicated dual-use function. More...

virtual bool	CheckWhetherSkipEffect (const EffectSettings &settings) const =0
	After Init(), tell whether Process() should be skipped. More...

virtual double	CalcPreviewInputLength (const EffectSettings &settings, double previewLength) const =0

void	SetLinearEffectFlag (bool linearEffectFlag)

void	SetPreviewFullSelectionFlag (bool previewDurationFlag)

bool	IsPreviewing () const

void	IncludeNotSelectedPreviewTracks (bool includeNotSelected)

void	ReplaceProcessedTracks (const bool bGoodResult)

const TrackList *	inputTracks () const

const AudacityProject *	FindProject () const

virtual bool	ValidateUI (EffectSettings &settings)=0

virtual bool	CloseUI ()=0

Protected Attributes inherited from Effect
wxWeakRef< wxDialog >	mHostUIDialog
	This smart pointer tracks the lifetime of the dialog. More...

wxWindow *	mUIParent {}

Protected Attributes inherited from EffectBase
BasicUI::ProgressDialog *	mProgress {}

double	mProjectRate {}

WaveTrackFactory *	mFactory {}

std::shared_ptr< TrackList >	mOutputTracks

double	mT0 {}

double	mT1 {}

wxArrayString	mPresetNames

unsigned	mUIFlags { 0 }

Protected Attributes inherited from EffectUIClientInterface
friend	EffectUIValidator

friend	DefaultEffectUIValidator

Static Protected Attributes inherited from EffectBase
static int	nEffectsDone = 0

Detailed Description

A two-pass effect to reduce background noise.

The first pass is done over just noise. For each windowed sample of the sound, we take a FFT and then statistics are tabulated for each frequency band.

During the noise reduction phase, we start by setting a gain control for each frequency band such that if the sound has exceeded the previously-determined threshold, the gain is set to 0 dB, otherwise the gain is set lower (e.g. -18 dB), to suppress the noise. Then time-smoothing is applied so that the gain for each frequency band moves slowly, and then frequency-smoothing is applied so that a single frequency is never suppressed or boosted in isolation. Lookahead is employed; this effect is not designed for real-time but if it were, there would be a significant delay.

The gain controls are applied to the complex FFT of the signal, and then the inverse FFT is applied. A Hann window may be applied (depending on the advanced window types setting), and then the output signal is then pieced together using overlap/add.

Definition at line 18 of file NoiseReduction.h.

Constructor & Destructor Documentation

◆ EffectNoiseReduction()

EffectNoiseReduction::EffectNoiseReduction ( )

Definition at line 411 of file NoiseReduction.cpp.

: mSettings(std::make_unique<EffectNoiseReduction::Settings>())
{
   Init();
}

References StatefulEffectBase::Init().

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◆ ~EffectNoiseReduction()

EffectNoiseReduction::~EffectNoiseReduction ( )

virtual

Definition at line 417 of file NoiseReduction.cpp.

418{

419}

Member Function Documentation

◆ GetDescription()

TranslatableString EffectNoiseReduction::GetDescription ( ) const

overridevirtual

Reimplemented from Effect.

Definition at line 428 of file NoiseReduction.cpp.

{
   return XO("Removes background noise such as fans, tape noise, or hums");
}

References XO.

◆ GetSymbol()

ComponentInterfaceSymbol EffectNoiseReduction::GetSymbol ( ) const

overridevirtual

Reimplemented from Effect.

Definition at line 423 of file NoiseReduction.cpp.

{
   return Symbol;
}

References Symbol.

◆ GetType()

EffectType EffectNoiseReduction::GetType ( ) const

overridevirtual

Type determines how it behaves.

Reimplemented from Effect.

Definition at line 435 of file NoiseReduction.cpp.

{
   return EffectTypeProcess;
}

References EffectTypeProcess.

◆ Process()

bool EffectNoiseReduction::Process	(	EffectInstance &	instance,
		EffectSettings &	settings
	)

overridevirtual

Actually do the effect here.

Returns: success

Implements StatefulEffectBase.

Definition at line 623 of file NoiseReduction.cpp.

{
   // This same code will either reduce noise or profile it
 
   this->CopyInputTracks(); // Set up mOutputTracks.
 
   auto track = * (mOutputTracks->Selected< const WaveTrack >()).begin();
   if (!track)
      return false;
 
   // Initialize statistics if gathering them, or check for mismatched (advanced)
   // settings if reducing noise.
   if (mSettings->mDoProfile) {
      size_t spectrumSize = 1 + mSettings->WindowSize() / 2;
      mStatistics = std::make_unique<Statistics>
         (spectrumSize, track->GetRate(), mSettings->mWindowTypes);
   }
   else if (mStatistics->mWindowSize != mSettings->WindowSize()) {
      // possible only with advanced settings
      ::Effect::MessageBox(
         XO("You must specify the same window size for steps 1 and 2.") );
      return false;
   }
   else if (mStatistics->mWindowTypes != mSettings->mWindowTypes) {
      // A warning only
      ::Effect::MessageBox(
         XO("Warning: window types are not the same as for profiling.") );
   }
 
   eWindowFunctions inWindowType, outWindowType;
   switch (mSettings->mWindowTypes) {
   case WT_RECTANGULAR_HANN:
      inWindowType = eWinFuncRectangular;
      outWindowType = eWinFuncHann;
      break;
   case WT_HANN_RECTANGULAR:
      inWindowType = eWinFuncHann;
      outWindowType = eWinFuncRectangular;
      break;
   case WT_BLACKMAN_HANN:
      inWindowType = eWinFuncBlackman;
      outWindowType = eWinFuncHann;
      break;
   case WT_HAMMING_RECTANGULAR:
      inWindowType = eWinFuncHamming;
      outWindowType = eWinFuncRectangular;
      break;
   case WT_HAMMING_HANN:
      inWindowType = eWinFuncHamming;
      outWindowType = eWinFuncHann;
      break;
   default:
      wxASSERT(false);
      [[fallthrough]] ;
   case WT_HANN_HANN:
      inWindowType = outWindowType = eWinFuncHann;
      break;
   }
   Worker worker{ inWindowType, outWindowType,
      *this, *mSettings, *mStatistics
#ifdef EXPERIMENTAL_SPECTRAL_EDITING
      , mF0, mF1
#endif
   };
   bool bGoodResult = worker.Process(*mOutputTracks, mT0, mT1);
   if (mSettings->mDoProfile) {
      if (bGoodResult)
         mSettings->mDoProfile = false; // So that "repeat last effect" will reduce noise
      else
         mStatistics.reset(); // So that profiling must be done again before noise reduction
   }
   this->ReplaceProcessedTracks(bGoodResult);
   return bGoodResult;
}

References Effect::CopyInputTracks(), eWinFuncBlackman, eWinFuncHamming, eWinFuncHann, eWinFuncRectangular, Effect::MessageBox(), EffectBase::mOutputTracks, mSettings, mStatistics, EffectBase::mT0, EffectBase::mT1, EffectBase::ReplaceProcessedTracks(), anonymous_namespace{NoiseReduction.cpp}::WT_BLACKMAN_HANN, anonymous_namespace{NoiseReduction.cpp}::WT_HAMMING_HANN, anonymous_namespace{NoiseReduction.cpp}::WT_HAMMING_RECTANGULAR, anonymous_namespace{NoiseReduction.cpp}::WT_HANN_HANN, anonymous_namespace{NoiseReduction.cpp}::WT_HANN_RECTANGULAR, anonymous_namespace{NoiseReduction.cpp}::WT_RECTANGULAR_HANN, and XO.

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◆ ShowHostInterface()

int EffectNoiseReduction::ShowHostInterface	(	wxWindow &	parent,
		const EffectDialogFactory &	factory,
		std::shared_ptr< EffectInstance > &	pInstance,
		EffectSettingsAccess &	access,
		bool	forceModal = `false`
	)

overridevirtual

An override still here for historical reasons, ignoring the factory and the access

We would like to make this effect behave more like others, but it does have its unusual two-pass nature. First choose and analyze an example of noise, then apply noise reduction to another selection. That is difficult to fit into the framework for managing settings of other effects.

Reimplemented from Effect.

Definition at line 446 of file NoiseReduction.cpp.

{
   // Assign the out parameter
   pInstance = MakeInstance();
   if (pInstance && !pInstance->Init())
      pInstance.reset();
 
   // to do: use forceModal correctly
 
   // Doesn't use the factory but substitutes its own dialog
 
   // We may want to twiddle the levels if we are setting
   // from a macro editing dialog
   return mSettings->PromptUser(this, access, parent,
      bool(mStatistics), forceModal);
}

References StatefulEffect::MakeInstance(), mSettings, and mStatistics.

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◆ TrackProgress()

bool Effect::TrackProgress	(	int	whichTrack,
		double	frac,
		const TranslatableString &	msg = `{}`
	)		const

Definition at line 179 of file Effect.cpp.

{
   auto updateResult = (mProgress ?
      mProgress->Poll(whichTrack + frac, (double) mNumTracks, msg) :
      ProgressResult::Success);
   return (updateResult != ProgressResult::Success);
}

References factory, Effect::IsInteractive(), Effect::mHostUIDialog, and EffectUIClientInterface::ShowClientInterface().

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Friends And Related Function Documentation

◆ Dialog

friend class Dialog

friend

Definition at line 53 of file NoiseReduction.h.

Member Data Documentation

◆ mSettings

std::unique_ptr<Settings> EffectNoiseReduction::mSettings

private

Definition at line 55 of file NoiseReduction.h.

Referenced by Process(), and ShowHostInterface().

◆ mStatistics

std::unique_ptr<Statistics> EffectNoiseReduction::mStatistics

private

Definition at line 56 of file NoiseReduction.h.

Referenced by EffectNoiseReduction::Worker::Classify(), EffectNoiseReduction::Worker::FinishTrackStatistics(), EffectNoiseReduction::Worker::GatherStatistics(), Process(), EffectNoiseReduction::Worker::Process(), and ShowHostInterface().

◆ Symbol

const ComponentInterfaceSymbol EffectNoiseReduction::Symbol { XO("Noise Reduction") }

static

Definition at line 20 of file NoiseReduction.h.

Referenced by GetSymbol().

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

Classes

Public Member Functions

Static Public Attributes

Private Attributes

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ EffectNoiseReduction()

◆ ~EffectNoiseReduction()

Member Function Documentation

◆ GetDescription()

◆ GetSymbol()

◆ GetType()

◆ Process()

◆ ShowHostInterface()

◆ TrackProgress()

Friends And Related Function Documentation

◆ Dialog

Member Data Documentation

◆ mSettings

◆ mStatistics

◆ Symbol