Distortion effect added

src/effects/Distortion.h

@@ -0,0 +1,218 @@
+/**********************************************************************
+
+  Audacity: A Digital Audio Editor
+
+  Distortion.h
+
+  Steve Daulton
+
+**********************************************************************/
+
+#ifndef __AUDACITY_EFFECT_DISTORTION__
+#define __AUDACITY_EFFECT_DISTORTION__
+
+#include <wx/arrstr.h>
+#include <wx/string.h>
+#include <wx/slider.h>
+#include <wx/textctrl.h>
+#include <wx/checkbox.h>
+
+#include <queue>
+
+#include "Effect.h"
+
+class ShuttleGui;
+
+#define DISTORTION_PLUGIN_SYMBOL XO("Distortion")
+#define STEPS 1024      // number of +ve or -ve steps in lookup tabe
+#define TABLESIZE 2049  // size of lookup table (steps * 2 + 1)
+
+class EffectDistortionState
+{
+public:
+   float       samplerate;
+   sampleCount skipcount;
+   int         tablechoiceindx;
+   bool        dcblock;
+   double      threshold;
+   double      noisefloor;
+   double      param1;
+   double      param2;
+   int         repeats;
+
+   // DC block filter variables
+   std::queue<float> queuesamples;
+   double queuetotal;
+};
+
+WX_DECLARE_OBJARRAY(EffectDistortionState, EffectDistortionStateArray);
+
+class EffectDistortion final : public Effect
+{
+public:
+   EffectDistortion();
+   virtual ~EffectDistortion();
+
+   struct Params
+   {
+      int    mTableChoiceIndx;
+      bool   mDCBlock;
+      double mThreshold_dB;
+      double mNoiseFloor;
+      double mParam1;
+      double mParam2;
+      int    mRepeats;
+   };
+
+   // IdentInterface implementation
+
+   wxString GetSymbol() override;
+   wxString GetDescription() override;
+
+   // EffectIdentInterface implementation
+
+   EffectType GetType() override;
+   bool SupportsRealtime() override;
+
+   // EffectClientInterface implementation
+
+   int GetAudioInCount() override;
+   int GetAudioOutCount() override;
+   bool ProcessInitialize(sampleCount totalLen, ChannelNames chanMap = NULL) override;
+   sampleCount ProcessBlock(float **inBlock, float **outBlock, sampleCount blockLen) override;
+   bool RealtimeInitialize() override;
+   bool RealtimeAddProcessor(int numChannels, float sampleRate) override;
+   bool RealtimeFinalize() override;
+   sampleCount RealtimeProcess(int group,
+                               float **inbuf,
+                               float **outbuf,
+                               sampleCount numSamples) override;
+   bool GetAutomationParameters(EffectAutomationParameters & parms) override;
+   bool SetAutomationParameters(EffectAutomationParameters & parms) override;
+   wxArrayString GetFactoryPresets() override;
+   bool LoadFactoryPreset(int id) override;
+
+   // Effect implementation
+
+   void PopulateOrExchange(ShuttleGui & S) override;
+   bool TransferDataToWindow() override;
+   bool TransferDataFromWindow() override;
+
+private:
+
+   enum control
+   {
+      ID_Type = 10000,
+      ID_DCBlock,
+      ID_Threshold,
+      ID_NoiseFloor,
+      ID_Param1,
+      ID_Param2,
+      ID_Repeats,
+   };
+   // EffectDistortion implementation
+
+   void InstanceInit(EffectDistortionState & data, float sampleRate);
+   sampleCount InstanceProcess(EffectDistortionState & data,
+                               float **inBlock,
+                               float **outBlock,
+                               sampleCount blockLen);
+
+   // Control Handlers
+
+   void OnTypeChoice(wxCommandEvent & evt);
+   void OnDCBlockCheckbox(wxCommandEvent & evt);
+   void OnThresholdText(wxCommandEvent & evt);
+   void OnThresholdSlider(wxCommandEvent & evt);
+   void OnNoiseFloorText(wxCommandEvent & evt);
+   void OnNoiseFloorSlider(wxCommandEvent & evt);
+   void OnParam1Text(wxCommandEvent & evt);
+   void OnParam1Slider(wxCommandEvent & evt);
+   void OnParam2Text(wxCommandEvent & evt);
+   void OnParam2Slider(wxCommandEvent & evt);
+   void OnRepeatsText(wxCommandEvent & evt);
+   void OnRepeatsSlider(wxCommandEvent & evt);
+   void UpdateUI();
+   void UpdateControl(control id, bool enable, wxString name);
+   void UpdateControlText(wxTextCtrl *textCtrl, wxString &string, bool enabled);
+
+   void MakeTable();
+   float WaveShaper(float sample);
+   float DCFilter(EffectDistortionState & data, float sample);
+
+   // Preset tables for gain lookup
+
+   void HardClip();           // hard clipping
+   void SoftClip();           // soft clipping
+   void ExponentialTable();   // exponential mapping
+   void LogarithmicTable();   // logarithmic mapping
+   void HalfSinTable();
+   void CubicTable();
+   void EvenHarmonicTable();
+   void SineTable();
+   void Leveller();           // 'Leveller' wavetable is modeled on the legacy effect of the same name.
+   void Rectifier();          // 0% = Dry, 50% = half-wave rectified, 100% = full-wave rectified (abs value).
+   void HardLimiter();        // Same effect as the LADSPA "hardLimiter 1413"
+
+   // Wavetable helper functions
+
+   void CopyHalfTable();   // for symmetric tables
+
+   // Used by Soft Clipping but could be used for other tables.
+   // Log curve formula: y = T + (((e^(RT - Rx)) - 1) / -R)
+   // where R is the ratio, T is the threshold, and x is from T to 1. 
+   inline float LogCurve(double threshold, float value, double ratio);
+
+   // Used by Cubic curve but could be used for other tables
+   // Cubic formula: y = x - (x^3 / 3.0)
+   inline double Cubic(double x);
+
+
+private:
+   EffectDistortionState mMaster;
+   EffectDistortionStateArray mSlaves;
+
+   double mTable[TABLESIZE];
+   double mThreshold;
+   bool mbSavedFilterState;
+
+   // mMakeupGain is used by some distortion types to pass the
+   // amount of gain required to bring overall effect gain to unity
+   double mMakeupGain;
+
+   int mTypChoiceIndex;
+   wxArrayString mTableTypes;
+
+   wxChoice *mTypeChoiceCtrl;
+   wxTextCtrl *mThresholdT;
+   wxTextCtrl *mNoiseFloorT;
+   wxTextCtrl *mParam1T;
+   wxTextCtrl *mParam2T;
+   wxTextCtrl *mRepeatsT;
+
+   wxSlider *mThresholdS;
+   wxSlider *mNoiseFloorS;
+   wxSlider *mParam1S;
+   wxSlider *mParam2S;
+   wxSlider *mRepeatsS;
+
+   wxCheckBox *mDCBlockCheckBox;
+
+   wxStaticText *mThresholdTxt;
+   wxStaticText *mNoiseFloorTxt;
+   wxStaticText *mParam1Txt;
+   wxStaticText *mParam2Txt;
+   wxStaticText *mRepeatsTxt;
+   
+   wxString mOldThresholdTxt;
+   wxString mOldmNoiseFloorTxt;
+   wxString mOldParam1Txt;
+   wxString mOldParam2Txt;
+   wxString mOldRepeatsTxt;
+
+   Params mParams;
+
+   DECLARE_EVENT_TABLE();
+};
+
+#endif

src/effects/LoadEffects.cpp

@@ -23,6 +23,7 @@
 #include "ChangeSpeed.h"
 #include "ClickRemoval.h"
 #include "Compressor.h"
+#include "Distortion.h"
 #include "DtmfGen.h"
 #include "Echo.h"
 #include "Paulstretch.h"
@@ -116,6 +117,7 @@
    EFFECT( CHANGESPEED,       EffectChangeSpeed, () )      \
    EFFECT( CLICKREMOVAL,      EffectClickRemoval, () )     \
    EFFECT( COMPRESSOR,        EffectCompressor, () )       \
+   EFFECT( DISTORTION,        EffectDistortion, () )       \
    EFFECT( ECHO,              EffectEcho, () )             \
    EFFECT( EQUALIZATION,      EffectEqualization, () )     \
    EFFECT( FADEIN,            EffectFade, (true) )         \