Amplify.h

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/**********************************************************************
 
  Audacity: A Digital Audio Editor
 
  Amplify.h
 
  Dominic Mazzoni
 
  This rewritten class supports a smart Amplify effect - it calculates
  the maximum amount of gain that can be applied to all tracks without
  causing clipping and selects this as the default parameter.
 
**********************************************************************/
 
#ifndef __AUDACITY_EFFECT_AMPLIFY__
#define __AUDACITY_EFFECT_AMPLIFY__
 
#include "StatefulPerTrackEffect.h"
#include "ShuttleAutomation.h"
#include <wx/weakref.h>
 
class wxSlider;
class wxCheckBox;
class wxTextCtrl;
class ShuttleGui;
 
class EffectAmplify final : public StatefulPerTrackEffect
{
public:
   static inline EffectAmplify *
   FetchParameters(EffectAmplify &e, EffectSettings &){ return &e; }
   static const ComponentInterfaceSymbol Symbol;
 
   EffectAmplify();
   virtual ~EffectAmplify();
 
   // ComponentInterface implementation
 
   ComponentInterfaceSymbol GetSymbol() const override;
   TranslatableString GetDescription() const override;
   ManualPageID ManualPage() const override;
 
   // EffectDefinitionInterface implementation
 
   EffectType GetType() const override;
   OptionalMessage LoadFactoryDefaults(EffectSettings &settings)
      const override;
   OptionalMessage DoLoadFactoryDefaults(EffectSettings &settings);
 
   unsigned GetAudioInCount() const override;
   unsigned GetAudioOutCount() const override;
   size_t ProcessBlock(EffectSettings &settings,
      const float *const *inBlock, float *const *outBlock, size_t blockLen)
      override;
 
   // Effect implementation
 
   bool Init() override;
   std::any BeginPreview(const EffectSettings &settings) override;
   std::unique_ptr<EffectEditor> PopulateOrExchange(
      ShuttleGui & S, EffectInstance &instance,
      EffectSettingsAccess &access, const EffectOutputs *pOutputs) override;
   bool TransferDataToWindow(const EffectSettings &settings) override;
   bool TransferDataFromWindow(EffectSettings &settings) override;
 
   std::shared_ptr<EffectInstance> MakeInstance() const override;
 
private:
   struct Instance : StatefulPerTrackEffect::Instance {
      using StatefulPerTrackEffect::Instance::Instance;
      ~Instance() override;
   };
 
   void ClampRatio();
 
   // EffectAmplify implementation
 
   void OnAmpText(wxCommandEvent & evt);
   void OnPeakText(wxCommandEvent & evt);
   void OnAmpSlider(wxCommandEvent & evt);
   void OnClipCheckBox(wxCommandEvent & evt);
   void CheckClip();
 
private:
   wxWeakRef<wxWindow> mUIParent{};
 
   double mPeak      = 1.0;
 
   double mRatio     = 1.0;
   double mRatioClip = 1.0;   // maximum value of mRatio which does not cause clipping
   double mAmp       = 0.0;
   double mNewPeak   = 1.0;
   bool   mCanClip   = true;
 
   wxSlider *mAmpS;
   wxTextCtrl *mAmpT;
   wxTextCtrl *mNewPeakT;
   wxCheckBox *mClip;
 
   const EffectParameterMethods& Parameters() const override;
 
   DECLARE_EVENT_TABLE()
 
static constexpr EffectParameter Ratio{ &EffectAmplify::mRatio,
   L"Ratio",            0.9f,       0.003162f,  316.227766f,   1.0f  };
// Amp is not saved in settings!
static constexpr EffectParameter Amp{ &EffectAmplify::mAmp,
   L"",                -0.91515f,  -50.0f,     50.0f,         10.0f };
static constexpr EffectParameter Clipping{ &EffectAmplify::mCanClip,
   L"AllowClipping",    false,    false,  true,    1  };
};
 
#endif // __AUDACITY_EFFECT_AMPLIFY__