lbajardsilogic@0: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
lbajardsilogic@0: 
lbajardsilogic@0: /*
lbajardsilogic@0:     Sonic Visualiser
lbajardsilogic@0:     An audio file viewer and annotation editor.
lbajardsilogic@0:     Centre for Digital Music, Queen Mary, University of London.
lbajardsilogic@0:     This file copyright 2006 Chris Cannam.
lbajardsilogic@0:     
lbajardsilogic@0:     This program is free software; you can redistribute it and/or
lbajardsilogic@0:     modify it under the terms of the GNU General Public License as
lbajardsilogic@0:     published by the Free Software Foundation; either version 2 of the
lbajardsilogic@0:     License, or (at your option) any later version.  See the file
lbajardsilogic@0:     COPYING included with this distribution for more information.
lbajardsilogic@0: */
lbajardsilogic@0: 
lbarthelemy@187: #include <cmath>
lbarthelemy@187: 
lbajardsilogic@0: #include "system/System.h"
lbajardsilogic@0: #include "Pitch.h"
lbajardsilogic@0: #include "Preferences.h"
lbajardsilogic@0: 
lbarthelemy@187: 
lbajardsilogic@0: 
lbajardsilogic@0: float
lbajardsilogic@0: Pitch::getFrequencyForPitch(int midiPitch,
lbajardsilogic@0: 			    float centsOffset,
lbajardsilogic@0: 			    float concertA)
lbajardsilogic@0: {
lbajardsilogic@0:     if (concertA <= 0.0) {
lbajardsilogic@0:         concertA = Preferences::getInstance()->getTuningFrequency();
lbajardsilogic@0:     }
lbajardsilogic@0:     float p = float(midiPitch) + (centsOffset / 100);
lbajardsilogic@0:     return concertA * powf(2.0, (p - 69.0) / 12.0);
lbajardsilogic@0: }
lbajardsilogic@0: 
lbajardsilogic@0: int
lbajardsilogic@0: Pitch::getPitchForFrequency(float frequency,
lbajardsilogic@0: 			    float *centsOffsetReturn,
lbajardsilogic@0: 			    float concertA)
lbajardsilogic@0: {
lbajardsilogic@0:     if (concertA <= 0.0) {
lbajardsilogic@0:         concertA = Preferences::getInstance()->getTuningFrequency();
lbajardsilogic@0:     }
lbajardsilogic@0:     float p = 12.0 * (log(frequency / (concertA / 2.0)) / log(2.0)) + 57.0;
lbajardsilogic@0: 
lbajardsilogic@0:     int midiPitch = int(p + 0.00001);
lbajardsilogic@0:     float centsOffset = (p - midiPitch) * 100.0;
lbajardsilogic@0: 
lbajardsilogic@0:     if (centsOffset >= 50.0) {
lbajardsilogic@0: 	midiPitch = midiPitch + 1;
lbajardsilogic@0: 	centsOffset = -(100.0 - centsOffset);
lbajardsilogic@0:     }
lbajardsilogic@0:     
lbajardsilogic@0:     if (centsOffsetReturn) *centsOffsetReturn = centsOffset;
lbajardsilogic@0:     return midiPitch;
lbajardsilogic@0: }
lbajardsilogic@0: 
lbajardsilogic@0: static QString notes[] = {
lbajardsilogic@0:     "C%1",  "C#%1", "D%1",  "D#%1",
lbajardsilogic@0:     "E%1",  "F%1",  "F#%1", "G%1",
lbajardsilogic@0:     "G#%1", "A%1",  "A#%1", "B%1"
lbajardsilogic@0: };
lbajardsilogic@0: 
lbajardsilogic@0: static QString flatNotes[] = {
lbajardsilogic@0:     "C%1",  "Db%1", "D%1",  "Eb%1",
lbajardsilogic@0:     "E%1",  "F%1",  "Gb%1", "G%1",
lbajardsilogic@0:     "Ab%1", "A%1",  "Bb%1", "B%1"
lbajardsilogic@0: };
lbajardsilogic@0: 
lbajardsilogic@0: QString
lbajardsilogic@0: Pitch::getPitchLabel(int midiPitch,
lbajardsilogic@0: 		     float centsOffset,
lbajardsilogic@0: 		     bool useFlats)
lbajardsilogic@0: {
lbajardsilogic@0:     int octave = -2;
lbajardsilogic@0: 
lbajardsilogic@0:     if (midiPitch < 0) {
lbajardsilogic@0: 	while (midiPitch < 0) {
lbajardsilogic@0: 	    midiPitch += 12;
lbajardsilogic@0: 	    --octave;
lbajardsilogic@0: 	}
lbajardsilogic@0:     } else {
lbajardsilogic@0: 	octave = midiPitch / 12 - 2;
lbajardsilogic@0:     }
lbajardsilogic@0: 
lbajardsilogic@0:     QString plain = (useFlats ? flatNotes : notes)[midiPitch % 12].arg(octave);
lbajardsilogic@0: 
lbajardsilogic@0:     int ic = lrintf(centsOffset);
lbajardsilogic@0:     if (ic == 0) return plain;
lbajardsilogic@0:     else if (ic > 0) return QString("%1+%2c").arg(plain).arg(ic);
lbajardsilogic@0:     else return QString("%1%2c").arg(plain).arg(ic);
lbajardsilogic@0: }
lbajardsilogic@0: 
lbajardsilogic@0: QString
lbajardsilogic@0: Pitch::getPitchLabelForFrequency(float frequency,
lbajardsilogic@0: 				 float concertA,
lbajardsilogic@0: 				 bool useFlats)
lbajardsilogic@0: {
lbajardsilogic@0:     if (concertA <= 0.0) {
lbajardsilogic@0:         concertA = Preferences::getInstance()->getTuningFrequency();
lbajardsilogic@0:     }
lbajardsilogic@0:     float centsOffset = 0.0;
lbajardsilogic@0:     int midiPitch = getPitchForFrequency(frequency, &centsOffset, concertA);
lbajardsilogic@0:     return getPitchLabel(midiPitch, centsOffset, useFlats);
lbajardsilogic@0: }
lbajardsilogic@0: