Mercurial > hg > svcore
view base/Pitch.cpp @ 335:02d2ad95ea52 spectrogram-cache-rejig
* Get storage advice for each cache in an FFT data server. Allows us to be
more confident about the actual memory situation and cut over from memory
to disc part way through an FFT calculation if necessary. StorageAdviser
is now a bit too optimistic though (it's too keen to allocate large numbers
of small blocks in memory).
author | Chris Cannam |
---|---|
date | Tue, 13 Nov 2007 13:54:10 +0000 |
parents | e412f65884ee |
children | 0a44caddd9fe |
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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ /* Sonic Visualiser An audio file viewer and annotation editor. Centre for Digital Music, Queen Mary, University of London. This file copyright 2006 Chris Cannam. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. See the file COPYING included with this distribution for more information. */ #include "Pitch.h" #include "Preferences.h" #include <cmath> float Pitch::getFrequencyForPitch(int midiPitch, float centsOffset, float concertA) { if (concertA <= 0.0) { concertA = Preferences::getInstance()->getTuningFrequency(); } float p = float(midiPitch) + (centsOffset / 100); return concertA * powf(2.0, (p - 69.0) / 12.0); } int Pitch::getPitchForFrequency(float frequency, float *centsOffsetReturn, float concertA) { if (concertA <= 0.0) { concertA = Preferences::getInstance()->getTuningFrequency(); } float p = 12.0 * (log(frequency / (concertA / 2.0)) / log(2.0)) + 57.0; int midiPitch = int(p + 0.00001); float centsOffset = (p - midiPitch) * 100.0; if (centsOffset >= 50.0) { midiPitch = midiPitch + 1; centsOffset = -(100.0 - centsOffset); } if (centsOffsetReturn) *centsOffsetReturn = centsOffset; return midiPitch; } static QString notes[] = { "C%1", "C#%1", "D%1", "D#%1", "E%1", "F%1", "F#%1", "G%1", "G#%1", "A%1", "A#%1", "B%1" }; static QString flatNotes[] = { "C%1", "Db%1", "D%1", "Eb%1", "E%1", "F%1", "Gb%1", "G%1", "Ab%1", "A%1", "Bb%1", "B%1" }; QString Pitch::getPitchLabel(int midiPitch, float centsOffset, bool useFlats) { int octave = -2; if (midiPitch < 0) { while (midiPitch < 0) { midiPitch += 12; --octave; } } else { octave = midiPitch / 12 - 2; } QString plain = (useFlats ? flatNotes : notes)[midiPitch % 12].arg(octave); int ic = lrintf(centsOffset); if (ic == 0) return plain; else if (ic > 0) return QString("%1+%2c").arg(plain).arg(ic); else return QString("%1%2c").arg(plain).arg(ic); } QString Pitch::getPitchLabelForFrequency(float frequency, float concertA, bool useFlats) { if (concertA <= 0.0) { concertA = Preferences::getInstance()->getTuningFrequency(); } float centsOffset = 0.0; int midiPitch = getPitchForFrequency(frequency, ¢sOffset, concertA); return getPitchLabel(midiPitch, centsOffset, useFlats); } bool Pitch::isFrequencyInMidiRange(float frequency, float concertA) { float centsOffset = 0.0; int midiPitch = getPitchForFrequency(frequency, ¢sOffset, concertA); return (midiPitch >= 0 && midiPitch < 128); }