ChangeSpeed.cpp

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/**********************************************************************
 
  Audacity: A Digital Audio Editor
 
  ChangeSpeed.cpp
 
  Vaughan Johnson, Dominic Mazzoni
 
*******************************************************************//*******************************************************************/
 
 
#include "ChangeSpeed.h"
#include "EffectEditor.h"
#include "LoadEffects.h"
 
#include <math.h>
 
#include <wx/choice.h>
#include <wx/slider.h>
 
#include "ConfigInterface.h"
#include "../LabelTrack.h"
#include "Prefs.h"
#include "Resample.h"
#include "ShuttleGui.h"
#include "SyncLock.h"
#include "../widgets/NumericTextCtrl.h"
#include "../widgets/valnum.h"
 
#include "TimeWarper.h"
#include "WaveClip.h"
#include "WaveTrack.h"
 
#include "NumericConverterFormats.h"
 
enum
{
   ID_PercentChange = 10000,
   ID_Multiplier,
   ID_FromVinyl,
   ID_ToVinyl,
   ID_ToLength
};
 
// the standard vinyl rpm choices
// If the percent change is not one of these ratios, the choice control gets "n/a".
enum kVinyl
{
   kVinyl_33AndAThird = 0,
   kVinyl_45,
   kVinyl_78,
   kVinyl_NA
};
 
static const TranslatableStrings kVinylStrings{
   XO("33\u2153"),
   XO("45"),
   XO("78"),
   /* i18n-hint: n/a is an English abbreviation meaning "not applicable". */
   XO("n/a"),
};
 
// Soundtouch is not reasonable below -99% or above 3000%.
 
const EffectParameterMethods& EffectChangeSpeed::Parameters() const
{
   static CapturedParameters<EffectChangeSpeed,
      Percentage
   > parameters;
   return parameters;
}
 
// We warp the slider to go up to 400%, but user can enter higher values
static const double kSliderMax = 100.0;         // warped above zero to actually go up to 400%
static const double kSliderWarp = 1.30105;      // warp power takes max from 100 to 400.
 
//
// EffectChangeSpeed
//
 
const ComponentInterfaceSymbol EffectChangeSpeed::Symbol
{ XO("Change Speed") };
 
namespace{ BuiltinEffectsModule::Registration< EffectChangeSpeed > reg; }
 
BEGIN_EVENT_TABLE(EffectChangeSpeed, wxEvtHandler)
    EVT_TEXT(ID_PercentChange, EffectChangeSpeed::OnText_PercentChange)
    EVT_TEXT(ID_Multiplier, EffectChangeSpeed::OnText_Multiplier)
    EVT_SLIDER(ID_PercentChange, EffectChangeSpeed::OnSlider_PercentChange)
    EVT_CHOICE(ID_FromVinyl, EffectChangeSpeed::OnChoice_Vinyl)
    EVT_CHOICE(ID_ToVinyl, EffectChangeSpeed::OnChoice_Vinyl)
    EVT_TEXT(ID_ToLength, EffectChangeSpeed::OnTimeCtrl_ToLength)
    EVT_COMMAND(ID_ToLength, EVT_TIMETEXTCTRL_UPDATED, EffectChangeSpeed::OnTimeCtrlUpdate)
END_EVENT_TABLE()
 
EffectChangeSpeed::EffectChangeSpeed()
{
   Parameters().Reset(*this);
 
   mFromVinyl = kVinyl_33AndAThird;
   mToVinyl = kVinyl_33AndAThird;
   mFromLength = 0.0;
   mToLength = 0.0;
   mFormat = NumericConverterFormats::DefaultSelectionFormat();
   mbLoopDetect = false;
 
   SetLinearEffectFlag(true);
}
 
EffectChangeSpeed::~EffectChangeSpeed()
{
}
 
// ComponentInterface implementation
 
ComponentInterfaceSymbol EffectChangeSpeed::GetSymbol() const
{
   return Symbol;
}
 
TranslatableString EffectChangeSpeed::GetDescription() const
{
   return XO("Changes the speed of a track, also changing its pitch");
}
 
ManualPageID EffectChangeSpeed::ManualPage() const
{
   return L"Change_Speed";
}
 
 
// EffectDefinitionInterface implementation
 
EffectType EffectChangeSpeed::GetType() const
{
   return EffectTypeProcess;
}
 
OptionalMessage EffectChangeSpeed::LoadFactoryDefaults(EffectSettings &settings) const
{
   // To do: externalize state so const_cast isn't needed
   return const_cast<EffectChangeSpeed&>(*this).DoLoadFactoryDefaults(settings);
}
 
OptionalMessage
EffectChangeSpeed::DoLoadFactoryDefaults(EffectSettings &settings)
{
   mFromVinyl = kVinyl_33AndAThird;
   mFormat = NumericConverterFormats::DefaultSelectionFormat();
 
   return Effect::LoadFactoryDefaults(settings);
}
 
// Effect implementation
 
bool EffectChangeSpeed::CheckWhetherSkipEffect(const EffectSettings &) const
{
   return (m_PercentChange == 0.0);
}
 
double EffectChangeSpeed::CalcPreviewInputLength(
   const EffectSettings &, double previewLength) const
{
   return previewLength * (100.0 + m_PercentChange) / 100.0;
}
 
bool EffectChangeSpeed::Init()
{
   // The selection might have changed since the last time EffectChangeSpeed
   // was invoked, so recalculate the Length parameters.
   mFromLength = mT1 - mT0;
   return true;
}
 
bool EffectChangeSpeed::Process(EffectInstance &, EffectSettings &)
{
   // Similar to EffectSoundTouch::Process()
 
   // Iterate over each track.
   // All needed because this effect needs to introduce
   // silence in the sync-lock group tracks to keep sync
   CopyInputTracks(true); // Set up mOutputTracks.
   bool bGoodResult = true;
 
   mCurTrackNum = 0;
   mMaxNewLength = 0.0;
 
   mFactor = 100.0 / (100.0 + m_PercentChange);
 
   mOutputTracks->Any().VisitWhile( bGoodResult,
      [&](LabelTrack *lt) {
         if (SyncLock::IsSelectedOrSyncLockSelected(lt))
         {
            if (!ProcessLabelTrack(lt))
               bGoodResult = false;
         }
      },
      [&](WaveTrack *pOutWaveTrack, const Track::Fallthrough &fallthrough) {
         if (!pOutWaveTrack->GetSelected())
            return fallthrough();
 
         //Get start and end times from track
         mCurT0 = pOutWaveTrack->GetStartTime();
         mCurT1 = pOutWaveTrack->GetEndTime();
 
         //Set the current bounds to whichever left marker is
         //greater and whichever right marker is less:
         mCurT0 = wxMax(mT0, mCurT0);
         mCurT1 = wxMin(mT1, mCurT1);
 
         // Process only if the right marker is to the right of the left marker
         if (mCurT1 > mCurT0) {
            //Transform the marker timepoints to samples
            auto start = pOutWaveTrack->TimeToLongSamples(mCurT0);
            auto end = pOutWaveTrack->TimeToLongSamples(mCurT1);
 
            //ProcessOne() (implemented below) processes a single track
            if (!ProcessOne(pOutWaveTrack, start, end))
               bGoodResult = false;
         }
         mCurTrackNum++;
      },
      [&](Track *t) {
         if (SyncLock::IsSyncLockSelected(t))
            t->SyncLockAdjust(mT1, mT0 + (mT1 - mT0) * mFactor);
      }
   );
 
   if (bGoodResult)
      ReplaceProcessedTracks(bGoodResult);
 
   // Update selection.
   mT1 = mT0 + (((mT1 - mT0) * 100.0) / (100.0 + m_PercentChange));
 
   return bGoodResult;
}
 
std::unique_ptr<EffectEditor> EffectChangeSpeed::PopulateOrExchange(
   ShuttleGui & S, EffectInstance &, EffectSettingsAccess &,
   const EffectOutputs *)
{
   mUIParent = S.GetParent();
 
   {
      wxString formatId;
      GetConfig(GetDefinition(), PluginSettings::Private,
         CurrentSettingsGroup(),
         wxT("TimeFormat"), formatId, mFormat.Internal());
      mFormat = NumericConverterFormats::Lookup(
         FormatterContext::SampleRateContext(mProjectRate),
         NumericConverterType_TIME(), formatId);
   }
   GetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(),
      wxT("VinylChoice"), mFromVinyl, mFromVinyl);
 
   S.SetBorder(5);
 
   S.StartVerticalLay(0);
   {
      S.AddSpace(0, 5);
      S.AddTitle(XO("Change Speed, affecting both Tempo and Pitch"));
      S.AddSpace(0, 10);
 
      // Speed multiplier and percent change controls.
      S.StartMultiColumn(4, wxCENTER);
      {
         mpTextCtrl_Multiplier = S.Id(ID_Multiplier)
            .Validator<FloatingPointValidator<double>>(
               3, &mMultiplier,
               NumValidatorStyle::THREE_TRAILING_ZEROES,
               Percentage.min / 100.0, ((Percentage.max / 100.0) + 1) )
            .AddTextBox(XXO("&Speed Multiplier:"), L"", 12);
 
         mpTextCtrl_PercentChange = S.Id(ID_PercentChange)
            .Validator<FloatingPointValidator<double>>(
               3, &m_PercentChange,
               NumValidatorStyle::THREE_TRAILING_ZEROES,
               Percentage.min, Percentage.max )
            .AddTextBox(XXO("Percent C&hange:"), L"", 12);
      }
      S.EndMultiColumn();
 
      // Percent change slider.
      S.StartHorizontalLay(wxEXPAND);
      {
         mpSlider_PercentChange = S.Id(ID_PercentChange)
            .Name(XO("Percent Change"))
            .Style(wxSL_HORIZONTAL)
            .AddSlider( {}, 0, (int)kSliderMax, (int)Percentage.min);
      }
      S.EndHorizontalLay();
 
      // Vinyl rpm controls.
      S.StartMultiColumn(5, wxCENTER);
      {
         /* i18n-hint: "rpm" is an English abbreviation meaning "revolutions per minute".
            "vinyl" refers to old-fashioned phonograph records */
         S.AddUnits(XO("Standard Vinyl rpm:"));
 
         mpChoice_FromVinyl = S.Id(ID_FromVinyl)
            /* i18n-hint: changing speed of audio "from" one value "to" another
             "rpm" means "revolutions per minute" as on a vinyl record turntable
             */
            .Name(XO("From rpm"))
            .MinSize( { 100, -1 } )
            /* i18n-hint: changing speed of audio "from" one value "to" another */
            .AddChoice(XXC("&from", "change speed"), kVinylStrings);
 
         mpChoice_ToVinyl = S.Id(ID_ToVinyl)
            /* i18n-hint: changing speed of audio "from" one value "to" another
             "rpm" means "revolutions per minute" as on a vinyl record turntable
             */
            .Name(XO("To rpm"))
            .MinSize( { 100, -1 } )
            /* i18n-hint: changing speed of audio "from" one value "to" another */
            .AddChoice(XXC("&to", "change speed"), kVinylStrings);
      }
      S.EndMultiColumn();
 
      // From/To time controls.
      S.StartStatic(XO("Selection Length"), 0);
      {
         S.StartMultiColumn(2, wxALIGN_LEFT);
         {
            S.AddPrompt(XXO("C&urrent Length:"));
 
            mpFromLengthCtrl = safenew
                  NumericTextCtrl(FormatterContext::SampleRateContext(mProjectRate),
                                 S.GetParent(), wxID_ANY,
                                 NumericConverterType_TIME(),
                                 mFormat,
                                 mFromLength,
                                 NumericTextCtrl::Options{}
                                  .ReadOnly(true)
                                  .MenuEnabled(false));
 
            S.ToolTip(XO("Current length of selection."))
               /* i18n-hint: changing speed of audio "from" one value "to" another */
               .Name(XC("from", "change speed"))
               .Position(wxALIGN_LEFT)
               .AddWindow(mpFromLengthCtrl);
 
            S.AddPrompt(XXO("&New Length:"));
 
            mpToLengthCtrl = safenew
                  NumericTextCtrl(FormatterContext::SampleRateContext(mProjectRate),
                                 S.GetParent(), ID_ToLength,
                                 NumericConverterType_TIME(),
                                 mFormat,
                                 mToLength);
 
            /* i18n-hint: changing speed of audio "from" one value "to" another */
            S.Name(XC("to", "change speed"))
               .Position(wxALIGN_LEFT)
               .AddWindow(mpToLengthCtrl);
         }
         S.EndMultiColumn();
      }
      S.EndStatic();
   }
   S.EndVerticalLay();
   return nullptr;
}
 
bool EffectChangeSpeed::TransferDataToWindow(const EffectSettings &)
{
   mbLoopDetect = true;
 
   if (!mUIParent->TransferDataToWindow())
   {
      return false;
   }
 
   if (mFromVinyl == kVinyl_NA)
   {
      mFromVinyl = kVinyl_33AndAThird;
   }
 
   Update_Text_PercentChange();
   Update_Text_Multiplier();
   Update_Slider_PercentChange();
   Update_TimeCtrl_ToLength();
 
   // Set from/to Vinyl controls - mFromVinyl must be set first.
   mpChoice_FromVinyl->SetSelection(mFromVinyl);
   // Then update to get correct mToVinyl.
   Update_Vinyl();
   // Then update ToVinyl control.
   mpChoice_ToVinyl->SetSelection(mToVinyl);
 
   // Set From Length control.
   // Set the format first so we can get sample accuracy.
   mpFromLengthCtrl->SetFormatName(mFormat);
   mpFromLengthCtrl->SetValue(mFromLength);
 
   mbLoopDetect = false;
 
   return true;
}
 
bool EffectChangeSpeed::TransferDataFromWindow(EffectSettings &)
{
   // mUIParent->TransferDataFromWindow() loses some precision, so save and restore it.
   double exactPercent = m_PercentChange;
   if (!mUIParent->Validate() || !mUIParent->TransferDataFromWindow())
   {
      return false;
   }
   m_PercentChange = exactPercent;
 
   // TODO: just visit these effect settings the default way
   SetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(), wxT("TimeFormat"), mFormat.Internal());
   SetConfig(GetDefinition(), PluginSettings::Private,
      CurrentSettingsGroup(), wxT("VinylChoice"), mFromVinyl);
 
   return true;
}
 
// EffectChangeSpeed implementation
 
// Labels are time-scaled linearly inside the affected region, and labels after
// the region are shifted along according to how the region size changed.
bool EffectChangeSpeed::ProcessLabelTrack(LabelTrack *lt)
{
   RegionTimeWarper warper { mT0, mT1,
      std::make_unique<LinearTimeWarper>(mT0, mT0,
                                         mT1, mT0 + (mT1-mT0)*mFactor) };
   lt->WarpLabels(warper);
   return true;
}
 
// ProcessOne() takes a track, transforms it to bunch of buffer-blocks,
// and calls libsamplerate code on these blocks.
bool EffectChangeSpeed::ProcessOne(WaveTrack * track,
                           sampleCount start, sampleCount end)
{
   if (track == NULL)
      return false;
 
   // initialization, per examples of Mixer::Mixer and
   // EffectSoundTouch::ProcessOne
 
 
   auto outputTrack = track->EmptyCopy();
 
   //Get the length of the selection (as double). len is
   //used simple to calculate a progress meter, so it is easier
   //to make it a double now than it is to do it later
   auto len = (end - start).as_double();
 
   // Initiate processing buffers, most likely shorter than
   // the length of the selection being processed.
   auto inBufferSize = track->GetMaxBlockSize();
 
   Floats inBuffer{ inBufferSize };
 
   // mFactor is at most 100-fold so this shouldn't overflow size_t
   auto outBufferSize = size_t( mFactor * inBufferSize + 10 );
   Floats outBuffer{ outBufferSize };
 
   // Set up the resampling stuff for this track.
   Resample resample(true, mFactor, mFactor); // constant rate resampling
 
   //Go through the track one buffer at a time. samplePos counts which
   //sample the current buffer starts at.
   bool bResult = true;
   auto samplePos = start;
   while (samplePos < end) {
      //Get a blockSize of samples (smaller than the size of the buffer)
      auto blockSize = limitSampleBufferSize(
         track->GetBestBlockSize(samplePos),
         end - samplePos
      );
 
      //Get the samples from the track and put them in the buffer
      track->GetFloats(inBuffer.get(), samplePos, blockSize);
 
      const auto results = resample.Process(mFactor,
                                    inBuffer.get(),
                                    blockSize,
                                    ((samplePos + blockSize) >= end),
                                    outBuffer.get(),
                                    outBufferSize);
      const auto outgen = results.second;
 
      if (outgen > 0)
         outputTrack->Append((samplePtr)outBuffer.get(), floatSample,
                             outgen);
 
      // Increment samplePos
      samplePos += results.first;
 
      // Update the Progress meter
      if (TrackProgress(mCurTrackNum, (samplePos - start).as_double() / len)) {
         bResult = false;
         break;
      }
   }
 
   // Flush the output WaveTrack (since it's buffered, too)
   outputTrack->Flush();
 
   // Take the output track and insert it in place of the original
   // sample data
   double newLength = outputTrack->GetEndTime();
   if (bResult)
   {
      // Silenced samples will be inserted in gaps between clips, so capture where these
      // gaps are for later deletion
      std::vector<std::pair<double, double>> gaps;
      double last = mCurT0;
      auto clips = track->SortedClipArray();
      auto front = clips.front();
      auto back = clips.back();
      for (auto &clip : clips) {
         auto st = clip->GetPlayStartTime();
         auto et = clip->GetPlayEndTime();
 
         if (st >= mCurT0 || et < mCurT1) {
            if (mCurT0 < st && clip == front) {
               gaps.push_back(std::make_pair(mCurT0, st));
            }
            else if (last < st && mCurT0 <= last ) {
               gaps.push_back(std::make_pair(last, st));
            }
 
            if (et < mCurT1 && clip == back) {
               gaps.push_back(std::make_pair(et, mCurT1));
            }
         }
         last = et;
      }
 
      LinearTimeWarper warper { mCurT0, mCurT0, mCurT1, mCurT0 + newLength };
 
      // Take the output track and insert it in place of the original sample data
      track->ClearAndPaste(mCurT0, mCurT1, outputTrack.get(), true, true, &warper);
 
      // Finally, recreate the gaps
      for (auto gap : gaps) {
         auto st = track->LongSamplesToTime(track->TimeToLongSamples(gap.first));
         auto et = track->LongSamplesToTime(track->TimeToLongSamples(gap.second));
         if (st >= mCurT0 && et <= mCurT1 && st != et)
         {
            track->SplitDelete(warper.Warp(st), warper.Warp(et));
         }
      }
   }
 
   if (newLength > mMaxNewLength)
      mMaxNewLength = newLength;
 
   return bResult;
}
 
// handler implementations for EffectChangeSpeed
 
void EffectChangeSpeed::OnText_PercentChange(wxCommandEvent & WXUNUSED(evt))
{
   if (mbLoopDetect)
      return;
 
   mpTextCtrl_PercentChange->GetValidator()->TransferFromWindow();
   UpdateUI();
 
   mbLoopDetect = true;
   Update_Text_Multiplier();
   Update_Slider_PercentChange();
   Update_Vinyl();
   Update_TimeCtrl_ToLength();
   mbLoopDetect = false;
}
 
void EffectChangeSpeed::OnText_Multiplier(wxCommandEvent & WXUNUSED(evt))
{
   if (mbLoopDetect)
      return;
 
   mpTextCtrl_Multiplier->GetValidator()->TransferFromWindow();
   m_PercentChange = 100 * (mMultiplier - 1);
   UpdateUI();
 
   mbLoopDetect = true;
   Update_Text_PercentChange();
   Update_Slider_PercentChange();
   Update_Vinyl();
   Update_TimeCtrl_ToLength();
   mbLoopDetect = false;
}
 
void EffectChangeSpeed::OnSlider_PercentChange(wxCommandEvent & WXUNUSED(evt))
{
   if (mbLoopDetect)
      return;
 
   m_PercentChange = (double)(mpSlider_PercentChange->GetValue());
   // Warp positive values to actually go up faster & further than negatives.
   if (m_PercentChange > 0.0)
      m_PercentChange = pow(m_PercentChange, kSliderWarp);
   UpdateUI();
 
   mbLoopDetect = true;
   Update_Text_PercentChange();
   Update_Text_Multiplier();
   Update_Vinyl();
   Update_TimeCtrl_ToLength();
   mbLoopDetect = false;
}
 
void EffectChangeSpeed::OnChoice_Vinyl(wxCommandEvent & WXUNUSED(evt))
{
   // Treat mpChoice_FromVinyl and mpChoice_ToVinyl as one control since we need
   // both to calculate Percent Change.
   mFromVinyl = mpChoice_FromVinyl->GetSelection();
   mToVinyl = mpChoice_ToVinyl->GetSelection();
   // Use this as the 'preferred' choice.
   if (mFromVinyl != kVinyl_NA) {
      SetConfig(GetDefinition(), PluginSettings::Private,
         CurrentSettingsGroup(), wxT("VinylChoice"), mFromVinyl);
   }
 
   // If mFromVinyl & mToVinyl are set, then there's a NEW percent change.
   if ((mFromVinyl != kVinyl_NA) && (mToVinyl != kVinyl_NA))
   {
      double fromRPM;
      double toRPM;
      switch (mFromVinyl) {
      default:
      case kVinyl_33AndAThird:   fromRPM = 33.0 + (1.0 / 3.0); break;
      case kVinyl_45:            fromRPM = 45.0; break;
      case kVinyl_78:            fromRPM = 78; break;
      }
      switch (mToVinyl) {
      default:
      case kVinyl_33AndAThird:   toRPM = 33.0 + (1.0 / 3.0); break;
      case kVinyl_45:            toRPM = 45.0; break;
      case kVinyl_78:            toRPM = 78; break;
      }
      m_PercentChange = ((toRPM * 100.0) / fromRPM) - 100.0;
      UpdateUI();
 
      mbLoopDetect = true;
      Update_Text_PercentChange();
      Update_Text_Multiplier();
      Update_Slider_PercentChange();
      Update_TimeCtrl_ToLength();
   }
   mbLoopDetect = false;
}
 
void EffectChangeSpeed::OnTimeCtrl_ToLength(wxCommandEvent & WXUNUSED(evt))
{
   if (mbLoopDetect)
      return;
 
   mToLength = mpToLengthCtrl->GetValue();
   // Division by (double) 0.0 is not an error and we want to show "infinite" in
   // text controls, so take care that we handle infinite values when they occur.
   m_PercentChange = ((mFromLength * 100.0) / mToLength) - 100.0;
   UpdateUI();
 
   mbLoopDetect = true;
 
   Update_Text_PercentChange();
   Update_Text_Multiplier();
   Update_Slider_PercentChange();
   Update_Vinyl();
 
   mbLoopDetect = false;
}
 
void EffectChangeSpeed::OnTimeCtrlUpdate(wxCommandEvent & evt)
{
   mFormat = NumericConverterFormats::Lookup(
      FormatterContext::SampleRateContext(mProjectRate),
      NumericConverterType_TIME(), evt.GetString());
 
   mpFromLengthCtrl->SetFormatName(mFormat);
   // Update From/To Length controls (precision has changed).
   mpToLengthCtrl->SetValue(mToLength);
   mpFromLengthCtrl->SetValue(mFromLength);
}
 
// helper functions
 
void EffectChangeSpeed::Update_Text_PercentChange()
// Update Text Percent control from percent change.
{
   mpTextCtrl_PercentChange->GetValidator()->TransferToWindow();
}
 
void EffectChangeSpeed::Update_Text_Multiplier()
// Update Multiplier control from percent change.
{
   mMultiplier =  1 + (m_PercentChange) / 100.0;
   mpTextCtrl_Multiplier->GetValidator()->TransferToWindow();
}
 
void EffectChangeSpeed::Update_Slider_PercentChange()
// Update Slider Percent control from percent change.
{
   auto unwarped = std::min<double>(m_PercentChange, Percentage.max);
   if (unwarped > 0.0)
      // Un-warp values above zero to actually go up to kSliderMax.
      unwarped = pow(m_PercentChange, (1.0 / kSliderWarp));
 
   // Caution: m_PercentChange could be infinite.
   int unwarpedi = (int)(unwarped + 0.5);
   unwarpedi = std::min<int>(unwarpedi, (int)kSliderMax);
 
   mpSlider_PercentChange->SetValue(unwarpedi);
}
 
void EffectChangeSpeed::Update_Vinyl()
// Update Vinyl controls from percent change.
{
   // Match Vinyl rpm when within 0.01% of a standard ratio.
   // Ratios calculated as: ((toRPM / fromRPM) - 1) * 100 * 100
 
   // Caution: m_PercentChange could be infinite
   int ratio = (int)((m_PercentChange * 100) + 0.5);
 
   switch (ratio)
   {
      case 0: // toRPM is the same as fromRPM
         if (mFromVinyl != kVinyl_NA) {
            mpChoice_ToVinyl->SetSelection(mpChoice_FromVinyl->GetSelection());
         } else {
            // Use the last saved option.
            GetConfig(GetDefinition(), PluginSettings::Private,
               CurrentSettingsGroup(), wxT("VinylChoice"), mFromVinyl, 0);
            mpChoice_FromVinyl->SetSelection(mFromVinyl);
            mpChoice_ToVinyl->SetSelection(mFromVinyl);
         }
         break;
      case 3500:
         mpChoice_FromVinyl->SetSelection(kVinyl_33AndAThird);
         mpChoice_ToVinyl->SetSelection(kVinyl_45);
         break;
      case 13400:
         mpChoice_FromVinyl->SetSelection(kVinyl_33AndAThird);
         mpChoice_ToVinyl->SetSelection(kVinyl_78);
         break;
      case -2593:
         mpChoice_FromVinyl->SetSelection(kVinyl_45);
         mpChoice_ToVinyl->SetSelection(kVinyl_33AndAThird);
         break;
      case 7333:
         mpChoice_FromVinyl->SetSelection(kVinyl_45);
         mpChoice_ToVinyl->SetSelection(kVinyl_78);
         break;
      case -5727:
         mpChoice_FromVinyl->SetSelection(kVinyl_78);
         mpChoice_ToVinyl->SetSelection(kVinyl_33AndAThird);
         break;
      case -4231:
         mpChoice_FromVinyl->SetSelection(kVinyl_78);
         mpChoice_ToVinyl->SetSelection(kVinyl_45);
         break;
      default:
         mpChoice_ToVinyl->SetSelection(kVinyl_NA);
   }
   // and update variables.
   mFromVinyl = mpChoice_FromVinyl->GetSelection();
   mToVinyl = mpChoice_ToVinyl->GetSelection();
}
 
void EffectChangeSpeed::Update_TimeCtrl_ToLength()
// Update ToLength control from percent change.
{
   mToLength = (mFromLength * 100.0) / (100.0 + m_PercentChange);
 
   // Set the format first so we can get sample accuracy.
   mpToLengthCtrl->SetFormatName(mFormat);
   // Negative times do not make sense.
   // 359999 = 99h:59m:59s which is a little less disturbing than overflow characters
   // though it may still look a bit strange with some formats.
   mToLength = std::clamp<double>(mToLength, 0.0, 359999.0);
   mpToLengthCtrl->SetValue(mToLength);
}
 
void EffectChangeSpeed::UpdateUI()
// Disable OK and Preview if not in sensible range.
{
   EffectEditor::EnableApply(mUIParent,
      m_PercentChange >= Percentage.min && m_PercentChange <= Percentage.max);
}