Chris@49: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@19: 
Chris@19: /*
Chris@52:     Sonic Visualiser
Chris@52:     An audio file viewer and annotation editor.
Chris@52:     Centre for Digital Music, Queen Mary, University of London.
Chris@52:     This file copyright 2006 Chris Cannam.
Chris@19:     
Chris@52:     This program is free software; you can redistribute it and/or
Chris@52:     modify it under the terms of the GNU General Public License as
Chris@52:     published by the Free Software Foundation; either version 2 of the
Chris@52:     License, or (at your option) any later version.  See the file
Chris@52:     COPYING included with this distribution for more information.
Chris@19: */
Chris@19: 
Chris@19: #include "Pitch.h"
Chris@141: #include "Preferences.h"
Chris@573: #include "system/System.h"
Chris@19: 
Chris@19: #include <cmath>
Chris@19: 
Chris@19: float
Chris@19: Pitch::getFrequencyForPitch(int midiPitch,
Chris@19: 			    float centsOffset,
Chris@19: 			    float concertA)
Chris@19: {
Chris@141:     if (concertA <= 0.0) {
Chris@141:         concertA = Preferences::getInstance()->getTuningFrequency();
Chris@141:     }
Chris@19:     float p = float(midiPitch) + (centsOffset / 100);
Chris@19:     return concertA * powf(2.0, (p - 69.0) / 12.0);
Chris@19: }
Chris@19: 
Chris@19: int
Chris@19: Pitch::getPitchForFrequency(float frequency,
Chris@19: 			    float *centsOffsetReturn,
Chris@19: 			    float concertA)
Chris@19: {
Chris@141:     if (concertA <= 0.0) {
Chris@141:         concertA = Preferences::getInstance()->getTuningFrequency();
Chris@141:     }
Chris@19:     float p = 12.0 * (log(frequency / (concertA / 2.0)) / log(2.0)) + 57.0;
Chris@19: 
Chris@19:     int midiPitch = int(p + 0.00001);
Chris@19:     float centsOffset = (p - midiPitch) * 100.0;
Chris@19: 
Chris@19:     if (centsOffset >= 50.0) {
Chris@19: 	midiPitch = midiPitch + 1;
Chris@19: 	centsOffset = -(100.0 - centsOffset);
Chris@19:     }
Chris@19:     
Chris@19:     if (centsOffsetReturn) *centsOffsetReturn = centsOffset;
Chris@19:     return midiPitch;
Chris@19: }
Chris@19: 
Chris@373: int
Chris@373: Pitch::getPitchForFrequencyDifference(float frequencyA,
Chris@373:                                       float frequencyB,
Chris@373:                                       float *centsOffsetReturn,
Chris@373:                                       float concertA)
Chris@373: {
Chris@373:     if (concertA <= 0.0) {
Chris@373:         concertA = Preferences::getInstance()->getTuningFrequency();
Chris@373:     }
Chris@373: 
Chris@373:     if (frequencyA > frequencyB) {
Chris@373:         std::swap(frequencyA, frequencyB);
Chris@373:     }
Chris@373: 
Chris@373:     float pA = 12.0 * (log(frequencyA / (concertA / 2.0)) / log(2.0)) + 57.0;
Chris@373:     float pB = 12.0 * (log(frequencyB / (concertA / 2.0)) / log(2.0)) + 57.0;
Chris@373: 
Chris@373:     float p = pB - pA;
Chris@373: 
Chris@373:     int midiPitch = int(p + 0.00001);
Chris@373:     float centsOffset = (p - midiPitch) * 100.0;
Chris@373: 
Chris@373:     if (centsOffset >= 50.0) {
Chris@373: 	midiPitch = midiPitch + 1;
Chris@373: 	centsOffset = -(100.0 - centsOffset);
Chris@373:     }
Chris@373:     
Chris@373:     if (centsOffsetReturn) *centsOffsetReturn = centsOffset;
Chris@373:     return midiPitch;
Chris@373: }
Chris@373: 
Chris@19: static QString notes[] = {
Chris@19:     "C%1",  "C#%1", "D%1",  "D#%1",
Chris@19:     "E%1",  "F%1",  "F#%1", "G%1",
Chris@19:     "G#%1", "A%1",  "A#%1", "B%1"
Chris@19: };
Chris@19: 
Chris@26: static QString flatNotes[] = {
Chris@26:     "C%1",  "Db%1", "D%1",  "Eb%1",
Chris@26:     "E%1",  "F%1",  "Gb%1", "G%1",
Chris@26:     "Ab%1", "A%1",  "Bb%1", "B%1"
Chris@26: };
Chris@26: 
Chris@19: QString
Chris@19: Pitch::getPitchLabel(int midiPitch,
Chris@26: 		     float centsOffset,
Chris@26: 		     bool useFlats)
Chris@19: {
Chris@19:     int octave = -2;
Chris@19: 
Chris@19:     if (midiPitch < 0) {
Chris@19: 	while (midiPitch < 0) {
Chris@19: 	    midiPitch += 12;
Chris@19: 	    --octave;
Chris@19: 	}
Chris@19:     } else {
Chris@19: 	octave = midiPitch / 12 - 2;
Chris@19:     }
Chris@19: 
Chris@26:     QString plain = (useFlats ? flatNotes : notes)[midiPitch % 12].arg(octave);
Chris@19: 
Chris@19:     int ic = lrintf(centsOffset);
Chris@19:     if (ic == 0) return plain;
Chris@19:     else if (ic > 0) return QString("%1+%2c").arg(plain).arg(ic);
Chris@19:     else return QString("%1%2c").arg(plain).arg(ic);
Chris@19: }
Chris@19: 
Chris@19: QString
Chris@19: Pitch::getPitchLabelForFrequency(float frequency,
Chris@26: 				 float concertA,
Chris@26: 				 bool useFlats)
Chris@19: {
Chris@141:     if (concertA <= 0.0) {
Chris@141:         concertA = Preferences::getInstance()->getTuningFrequency();
Chris@141:     }
Chris@19:     float centsOffset = 0.0;
Chris@19:     int midiPitch = getPitchForFrequency(frequency, &centsOffset, concertA);
Chris@26:     return getPitchLabel(midiPitch, centsOffset, useFlats);
Chris@19: }
Chris@19: 
Chris@373: QString
Chris@373: Pitch::getLabelForPitchRange(int semis, float cents)
Chris@373: {
Chris@433:     if (semis > 0) {
Chris@433:         while (cents < 0.f) {
Chris@433:             --semis;
Chris@433:             cents += 100.f;
Chris@433:         }
Chris@433:     }
Chris@433:     if (semis < 0) {
Chris@433:         while (cents > 0.f) {
Chris@433:             ++semis;
Chris@433:             cents -= 100.f;
Chris@433:         }
Chris@433:     }
Chris@433: 
Chris@373:     int ic = lrintf(cents);
Chris@373: 
Chris@373:     if (ic == 0) {
Chris@373:         if (semis >= 12) {
Chris@373:             return QString("%1'%2").arg(semis/12).arg(semis - 12*(semis/12));
Chris@373:         } else {
Chris@373:             return QString("%1").arg(semis);
Chris@373:         }
Chris@373:     } else {
Chris@373:         if (ic > 0) {
Chris@373:             if (semis >= 12) {
Chris@373:                 return QString("%1'%2+%3c").arg(semis/12).arg(semis - 12*(semis/12)).arg(ic);
Chris@373:             } else {
Chris@373:                 return QString("%1+%3c").arg(semis).arg(ic);
Chris@373:             }
Chris@373:         } else {
Chris@373:             if (semis >= 12) {
Chris@373:                 return QString("%1'%2%3c").arg(semis/12).arg(semis - 12*(semis/12)).arg(ic);
Chris@373:             } else {
Chris@373:                 return QString("%1%3c").arg(semis).arg(ic);
Chris@373:             }
Chris@373:         }
Chris@373:     }
Chris@373: }
Chris@373: 
Chris@274: bool
Chris@274: Pitch::isFrequencyInMidiRange(float frequency,
Chris@274:                               float concertA)
Chris@274: {
Chris@274:     float centsOffset = 0.0;
Chris@274:     int midiPitch = getPitchForFrequency(frequency, &centsOffset, concertA);
Chris@274:     return (midiPitch >= 0 && midiPitch < 128);
Chris@274: }
Chris@274: