// Deduce m_FromFrequency from the samples at the beginning of
// the selection. Then set some other params accordingly.
void EffectChangePitch::DeduceFrequencies()
{
// As a neat trick, attempt to get the frequency of the note at the
// beginning of the selection.
SelectedTrackListOfKindIterator iter(Track::Wave, inputTracks());
WaveTrack *track = (WaveTrack *) iter.First();
if (track) {
double rate = track->GetRate();
// Auto-size window -- high sample rates require larger windowSize.
// Aim for around 2048 samples at 44.1 kHz (good down to about 100 Hz).
// To detect single notes, analysis period should be about 0.2 seconds.
// windowSize must be a power of 2.
const size_t windowSize =
// windowSize < 256 too inaccurate
std::max(256, wxRound(pow(2.0, floor((log(rate / 20.0)/log(2.0)) + 0.5))));
// we want about 0.2 seconds to catch the first note.
// number of windows rounded to nearest integer >= 1.
const unsigned numWindows =
std::max(1, wxRound((double)(rate / (5.0f * windowSize))));
double trackStart = track->GetStartTime();
double t0 = mT0 < trackStart? trackStart: mT0;
auto start = track->TimeToLongSamples(t0);
auto analyzeSize = windowSize * numWindows;
Floats buffer{ analyzeSize };
Floats freq{ windowSize / 2 };
Floats freqa{ windowSize / 2, true };
track->Get((samplePtr) buffer.get(), floatSample, start, analyzeSize);
for(unsigned i = 0; i < numWindows; i++) {
ComputeSpectrum(buffer.get() + i * windowSize, windowSize,
windowSize, rate, freq.get(), true);
for(size_t j = 0; j < windowSize / 2; j++)
freqa[j] += freq[j];
}
size_t argmax = 0;
for(size_t j = 1; j < windowSize / 2; j++)
if (freqa[j] > freqa[argmax])
argmax = j;
auto lag = (windowSize / 2 - 1) - argmax;
m_dStartFrequency = rate / lag;
}
double dFromMIDInote = FreqToMIDInote(m_dStartFrequency);
double dToMIDInote = dFromMIDInote + m_dSemitonesChange;
m_nFromPitch = PitchIndex(dFromMIDInote);
m_nFromOctave = PitchOctave(dFromMIDInote);
m_nToPitch = PitchIndex(dToMIDInote);
m_nToOctave = PitchOctave(dToMIDInote);
m_FromFrequency = m_dStartFrequency;
Calc_PercentChange();
Calc_ToFrequency();
}
void EffectChangePitch::OnText_FromFrequency(wxCommandEvent & WXUNUSED(evt))
{
if (m_bLoopDetect)
return;
// Empty string causes unpredictable results with ToDouble() and later calculations.
// Non-positive frequency makes no sense, but user might still be editing,
// so it's not an error, but we do not want to update the values/controls.
if (!m_pTextCtrl_FromFrequency->GetValidator()->TransferFromWindow())
{
EnableApply(false);
return;
}
double newFromMIDInote = FreqToMIDInote(m_FromFrequency);
m_nFromPitch = PitchIndex(newFromMIDInote);
m_nFromOctave = PitchOctave(newFromMIDInote);
Calc_ToPitch();
Calc_ToFrequency();
Calc_ToOctave(); // Call after Calc_ToFrequency().
m_bLoopDetect = true;
{
Update_Choice_FromPitch();
Update_Spin_FromOctave();
Update_Choice_ToPitch();
Update_Spin_ToOctave();
Update_Text_ToFrequency();
}
m_bLoopDetect = false;
// Success. Make sure OK and Preview are enabled, in case we disabled above during editing.
EnableApply(true);
}
void EffectChangePitch::Calc_ToOctave()
{
m_nToOctave = PitchOctave(FreqToMIDInote(m_ToFrequency));
}
// Deduce m_FromFrequency from the samples at the beginning of
// the selection. Then set some other params accordingly.
void EffectChangePitch::DeduceFrequencies()
{
// As a neat trick, attempt to get the frequency of the note at the
// beginning of the selection.
SelectedTrackListOfKindIterator iter(Track::Wave, mTracks);
WaveTrack *track = (WaveTrack *) iter.First();
if (track) {
double rate = track->GetRate();
// Auto-size window -- high sample rates require larger windowSize.
// Aim for around 2048 samples at 44.1 kHz (good down to about 100 Hz).
// To detect single notes, analysis period should be about 0.2 seconds.
// windowSize must be a power of 2.
int windowSize = wxRound(pow(2.0, floor((log(rate / 20.0)/log(2.0)) + 0.5)));
// windowSize < 256 too inaccurate
windowSize = (windowSize > 256)? windowSize : 256;
// we want about 0.2 seconds to catch the first note.
// number of windows rounded to nearest integer >= 1.
int numWindows = wxRound((double)(rate / (5.0f * windowSize)));
numWindows = (numWindows > 0)? numWindows : 1;
double trackStart = track->GetStartTime();
double t0 = mT0 < trackStart? trackStart: mT0;
sampleCount start = track->TimeToLongSamples(t0);
int analyzeSize = windowSize * numWindows;
float * buffer;
buffer = new float[analyzeSize];
float * freq;
freq = new float[windowSize/2];
float * freqa;
freqa = new float[windowSize/2];
int i, j, argmax;
int lag;
for(j=0; j<windowSize/2; j++)
freqa[j] = 0;
track->Get((samplePtr) buffer, floatSample, start, analyzeSize);
for(i=0; i<numWindows; i++) {
ComputeSpectrum(buffer+i*windowSize, windowSize,
windowSize, rate, freq, true);
for(j=0; j<windowSize/2; j++)
freqa[j] += freq[j];
}
argmax=0;
for(j=1; j<windowSize/2; j++)
if (freqa[j] > freqa[argmax])
argmax = j;
delete [] freq;
delete [] freqa;
delete [] buffer;
lag = (windowSize/2 - 1) - argmax;
m_dStartFrequency = rate / lag;
}
double dFromMIDInote = FreqToMIDInote(m_dStartFrequency);
double dToMIDInote = dFromMIDInote + m_dSemitonesChange;
m_nFromPitch = PitchIndex(dFromMIDInote);
m_nFromOctave = PitchOctave(dFromMIDInote);
m_nToPitch = PitchIndex(dToMIDInote);
m_nToOctave = PitchOctave(dToMIDInote);
m_FromFrequency = m_dStartFrequency;
Calc_PercentChange();
Calc_ToFrequency();
}