Chris@32: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@32: /* Copyright Chris Cannam - All Rights Reserved */
Chris@32: 
Chris@32: #include "NoteHypothesis.h"
Chris@32: 
Chris@32: #include <cmath>
Chris@32: 
Chris@35: using Vamp::RealTime;
Chris@32: 
Chris@32: NoteHypothesis::NoteHypothesis()
Chris@32: {
Chris@32:     m_state = New;
Chris@32: }
Chris@32: 
Chris@32: NoteHypothesis::~NoteHypothesis()
Chris@32: {
Chris@32: }
Chris@32: 
Chris@32: bool
Chris@32: NoteHypothesis::isWithinTolerance(Estimate s) const
Chris@32: {
Chris@32:     if (m_pending.empty()) {
Chris@32:         return true;
Chris@32:     }
Chris@32: 
Chris@32:     // check we are within a relatively close tolerance of the last
Chris@32:     // candidate
Chris@32:     Estimate last = m_pending[m_pending.size()-1];
Chris@32:     double r = s.freq / last.freq;
Chris@32:     int cents = lrint(1200.0 * (log(r) / log(2.0)));
Chris@32:     if (cents < -60 || cents > 60) return false;
Chris@32: 
Chris@32:     // and within a slightly bigger tolerance of the current mean
Chris@32:     double meanFreq = getMeanFrequency();
Chris@32:     r = s.freq / meanFreq;
Chris@32:     cents = lrint(1200.0 * (log(r) / log(2.0)));
Chris@32:     if (cents < -80 || cents > 80) return false;
Chris@32:     
Chris@32:     return true;
Chris@32: }
Chris@32: 
Chris@32: bool
Chris@32: NoteHypothesis::isOutOfDateFor(Estimate s) const
Chris@32: {
Chris@32:     if (m_pending.empty()) return false;
Chris@32: 
Chris@32:     return ((s.time - m_pending[m_pending.size()-1].time) > 
Chris@32:             RealTime::fromMilliseconds(40));
Chris@32: }
Chris@32: 
Chris@32: bool 
Chris@32: NoteHypothesis::isSatisfied() const
Chris@32: {
Chris@32:     if (m_pending.empty()) return false;
Chris@32:     
Chris@32:     double meanConfidence = 0.0;
Chris@32:     for (int i = 0; i < (int)m_pending.size(); ++i) {
Chris@32:         meanConfidence += m_pending[i].confidence;
Chris@32:     }
Chris@32:     meanConfidence /= m_pending.size();
Chris@32: 
Chris@32:     int lengthRequired = 10000;
Chris@32:     if (meanConfidence > 0.0) {
Chris@32:         lengthRequired = int(2.0 / meanConfidence + 0.5);
Chris@32:     }
Chris@32: 
Chris@32:     return ((int)m_pending.size() > lengthRequired);
Chris@32: }
Chris@32: 
Chris@32: bool
Chris@32: NoteHypothesis::accept(Estimate s)
Chris@32: {
Chris@32:     bool accept = false;
Chris@32: 
Chris@32:     switch (m_state) {
Chris@32: 
Chris@32:     case New:
Chris@32:         m_state = Provisional;
Chris@32:         accept = true;
Chris@32:         break;
Chris@32: 
Chris@32:     case Provisional:
Chris@32:         if (isOutOfDateFor(s)) {
Chris@32:             m_state = Rejected;
Chris@32:         } else if (isWithinTolerance(s)) {
Chris@32:             accept = true;
Chris@32:         }
Chris@32:         break;
Chris@32:         
Chris@32:     case Satisfied:
Chris@32:         if (isOutOfDateFor(s)) {
Chris@32:             m_state = Expired;
Chris@32:         } else if (isWithinTolerance(s)) {
Chris@32:             accept = true;
Chris@32:         }
Chris@32:         break;
Chris@32: 
Chris@32:     case Rejected:
Chris@32:         break;
Chris@32: 
Chris@32:     case Expired:
Chris@32:         break;
Chris@32:     }
Chris@32: 
Chris@32:     if (accept) {
Chris@32:         m_pending.push_back(s);
Chris@32:         if (m_state == Provisional && isSatisfied()) {
Chris@32:             m_state = Satisfied;
Chris@32:         }
Chris@32:     }
Chris@32: 
Chris@32:     return accept;
Chris@32: }        
Chris@32: 
Chris@32: NoteHypothesis::State
Chris@32: NoteHypothesis::getState() const
Chris@32: {
Chris@32:     return m_state;
Chris@32: }
Chris@32: 
Chris@32: NoteHypothesis::Estimates
Chris@32: NoteHypothesis::getAcceptedEstimates() const
Chris@32: {
Chris@32:     if (m_state == Satisfied || m_state == Expired) {
Chris@32:         return m_pending;
Chris@32:     } else {
Chris@32:         return Estimates();
Chris@32:     }
Chris@32: }
Chris@32: 
Chris@32: double
Chris@32: NoteHypothesis::getMeanFrequency() const
Chris@32: {
Chris@32:     double acc = 0.0;
Chris@34:     if (m_pending.empty()) return acc;
Chris@32:     for (int i = 0; i < (int)m_pending.size(); ++i) {
Chris@32:         acc += m_pending[i].freq;
Chris@32:     }
Chris@32:     acc /= m_pending.size();
Chris@32:     return acc;
Chris@32: }
Chris@32: 
Chris@32: NoteHypothesis::Note
Chris@32: NoteHypothesis::getAveragedNote() const
Chris@32: {
Chris@32:     Note n;
Chris@32: 
Chris@32:     if (!(m_state == Satisfied || m_state == Expired)) {
Chris@32:         n.freq = 0.0;
Chris@32:         n.time = RealTime::zeroTime;
Chris@32:         n.duration = RealTime::zeroTime;
Chris@32:         return n;
Chris@32:     }
Chris@32: 
Chris@32:     n.time = m_pending.begin()->time;
Chris@32: 
Chris@32:     Estimates::const_iterator i = m_pending.end();
Chris@32:     --i;
Chris@32:     n.duration = i->time - n.time;
Chris@32: 
Chris@32:     // just mean frequency for now, but this isn't at all right perceptually
Chris@32:     n.freq = getMeanFrequency();
Chris@32:     
Chris@32:     return n;
Chris@32: }
Chris@32: