def __init__(self, num_frets, tuning, capo):
# create the guitar model to get the pitch range
self.guitar = Guitar(num_frets, tuning, capo)
self.mei_doc = None
self.redistribute = False # whether or not to redistribute notes
def __init__(self, num_frets, tuning, capo):
# create the guitar model to get the pitch range
self.guitar = Guitar(num_frets, tuning, capo)
self.mei_doc = None
self.redistribute = False # whether or not to redistribute notes
class Guitarify:
'''
Class with functions to sanitize pitches of notes in an MEI file
to be ones that can be played on a specific guitar
'''
def __init__(self, num_frets, tuning, capo):
# create the guitar model to get the pitch range
self.guitar = Guitar(num_frets, tuning, capo)
self.mei_doc = None
self.redistribute = False # whether or not to redistribute notes
def sanitize_mei_file(self, mei_path, output_mei_path=None, prune=True):
self.mei_doc = XmlImport.documentFromFile(mei_path)
self._sanitize_mei(prune)
if output_mei_path:
XmlExport.meiDocumentToFile(self.mei_doc, str(output_mei_path))
else:
return XmlExport.meiDocumentToText(self.mei_doc)
def sanitize_mei_str(self, mei_str, output_mei_path=None, prune=True):
self.mei_doc = XmlImport.documentFromText(mei_str)
self._sanitize_mei(prune)
if output_mei_path:
XmlExport.meiDocumentToFile(self.mei_doc, str(output_mei_path))
else:
return XmlExport.meiDocumentToText(self.mei_doc)
def _sanitize_mei(self, prune):
'''
Remove (prune) or transpose notes in the mei document that are unable to
be performed on the guitar.
'''
lb_pitch, ub_pitch = self.guitar.get_pitch_range()
notes = self.mei_doc.getElementsByName('note')
for mei_n in notes[:]:
pname = str(mei_n.getAttribute('pname').value)
oct = int(mei_n.getAttribute('oct').value)
n = Note(pname, oct)
# make sure pitch is within the pitch range of the guitar
if n < lb_pitch:
if prune:
self._remove_note(mei_n)
else:
# attempt to transpose pitch
candidate_note = Note(pname, oct)
# jump by octave
step = 12
while candidate_note < lb_pitch:
candidate_note += step
step += 12
if candidate_note <= ub_pitch:
mei_n.addAttribute('pname', str(candidate_note.pname))
mei_n.addAttribute('oct', str(candidate_note.oct))
else:
self._remove_note(mei_n)
elif n > ub_pitch:
if prune:
self._remove_note(mei_n)
else:
# attempt to transpose pitch
candidate_note = Note(pname, oct)
# jump by octave
step = 12
while candidate_note > ub_pitch:
candidate_note -= step
step += 12
if candidate_note >= lb_pitch:
mei_n.addAttribute('pname', str(candidate_note.pname))
mei_n.addAttribute('oct', str(candidate_note.oct))
else:
self._remove_note(mei_n)
if prune and self.redistribute:
self._redistribute()
# now limit degree of polyphony to six
mei_chords = self.mei_doc.getElementsByName('chord')
for mei_c in mei_chords:
mei_notes = mei_c.getChildrenByName('note')
polyphony = len(mei_notes)
if polyphony > 6:
notes = sorted([Note(str(mei_n.getAttribute('pname').value), int(mei_n.getAttribute('oct').value), str(mei_n.getId())) for mei_n in mei_notes])
# discard notes with the highest pitch
for n in notes[6:]:
mei_n = self.mei_doc.getElementById(n.id)
mei_n.getParent().removeChild(mei_n)
def _remove_note(self, note):
'''
Remove a note from the MEI document
'''
note_container = note.getParent()
# remove the note
note_container.removeChild(note)
if note_container.getName() == 'chord':
layer = note_container.getParent()
notes_in_chord = note_container.getChildrenByName('note')
if len(notes_in_chord) == 0:
# this should never happen
layer.removeChild(note_container)
self.redistribute = True
elif len(notes_in_chord) == 1:
# there is only one note left, so it's no longer a chord
chord_when = note_container.getAttribute('when').value
notes_in_chord[0].addAttribute('when', chord_when)
layer.addChildBefore(note_container, notes_in_chord[0])
layer.removeChild(note_container)
else:
# remove timestamp from timeline
when_id = note.getAttribute('when').value
when = self.mei_doc.getElementById(when_id)
when.getParent().removeChild(when)
self.redistribute = True
def _redistribute(self):
'''
Redistribute notes in the measures to match the 4/4 time signature
'''
layers = self.mei_doc.getElementsByName('layer')
note_events = []
for l in layers:
note_events.extend(l.getChildren())
# remove all measures
for m in self.mei_doc.getElementsByName('measure'):
m.getParent().removeChild(m)
section = self.mei_doc.getElementsByName('section')[0]
score_def = self.mei_doc.getElementsByName('scoreDef')[0]
meter_count = int(score_def.getAttribute('meter.count').value)
# insert the note events again
note_container = None
for i, note_event in enumerate(note_events):
if i % meter_count == 0:
measure = MeiElement('measure')
measure.addAttribute('n', str(int(i/meter_count + 1)))
staff = MeiElement('staff')
staff.addAttribute('n', '1')
layer = MeiElement('layer')
layer.addAttribute('n', '1')
section.addChild(measure)
measure.addChild(staff)
staff.addChild(layer)
note_container = layer
note_container.addChild(note_event)
class Guitarify:
'''
Class with functions to sanitize pitches of notes in an MEI file
to be ones that can be played on a specific guitar
'''
def __init__(self, num_frets, tuning, capo):
# create the guitar model to get the pitch range
self.guitar = Guitar(num_frets, tuning, capo)
self.mei_doc = None
self.redistribute = False # whether or not to redistribute notes
def sanitize_mei_file(self, mei_path, output_mei_path=None, prune=True):
self.mei_doc = XmlImport.documentFromFile(mei_path)
self._sanitize_mei(prune)
if output_mei_path:
XmlExport.meiDocumentToFile(self.mei_doc, str(output_mei_path))
else:
return XmlExport.meiDocumentToText(self.mei_doc)
def sanitize_mei_str(self, mei_str, output_mei_path=None, prune=True):
self.mei_doc = XmlImport.documentFromText(mei_str)
self._sanitize_mei(prune)
if output_mei_path:
XmlExport.meiDocumentToFile(self.mei_doc, str(output_mei_path))
else:
return XmlExport.meiDocumentToText(self.mei_doc)
def _sanitize_mei(self, prune):
'''
Remove (prune) or transpose notes in the mei document that are unable to
be performed on the guitar.
'''
lb_pitch, ub_pitch = self.guitar.get_pitch_range()
notes = self.mei_doc.getElementsByName('note')
for mei_n in notes[:]:
pname = str(mei_n.getAttribute('pname').value)
oct = int(mei_n.getAttribute('oct').value)
n = Note(pname, oct)
# make sure pitch is within the pitch range of the guitar
if n < lb_pitch:
if prune:
self._remove_note(mei_n)
else:
# attempt to transpose pitch
candidate_note = Note(pname, oct)
# jump by octave
step = 12
while candidate_note < lb_pitch:
candidate_note += step
step += 12
if candidate_note <= ub_pitch:
mei_n.addAttribute('pname', str(candidate_note.pname))
mei_n.addAttribute('oct', str(candidate_note.oct))
else:
self._remove_note(mei_n)
elif n > ub_pitch:
if prune:
self._remove_note(mei_n)
else:
# attempt to transpose pitch
candidate_note = Note(pname, oct)
# jump by octave
step = 12
while candidate_note > ub_pitch:
candidate_note -= step
step += 12
if candidate_note >= lb_pitch:
mei_n.addAttribute('pname', str(candidate_note.pname))
mei_n.addAttribute('oct', str(candidate_note.oct))
else:
self._remove_note(mei_n)
if prune and self.redistribute:
self._redistribute()
# now limit degree of polyphony to six
mei_chords = self.mei_doc.getElementsByName('chord')
for mei_c in mei_chords:
mei_notes = mei_c.getChildrenByName('note')
polyphony = len(mei_notes)
if polyphony > 6:
notes = sorted([
Note(str(mei_n.getAttribute('pname').value),
int(mei_n.getAttribute('oct').value),
str(mei_n.getId())) for mei_n in mei_notes
])
# discard notes with the highest pitch
for n in notes[6:]:
mei_n = self.mei_doc.getElementById(n.id)
mei_n.getParent().removeChild(mei_n)
def _remove_note(self, note):
'''
Remove a note from the MEI document
'''
note_container = note.getParent()
# remove the note
note_container.removeChild(note)
if note_container.getName() == 'chord':
layer = note_container.getParent()
notes_in_chord = note_container.getChildrenByName('note')
if len(notes_in_chord) == 0:
# this should never happen
layer.removeChild(note_container)
self.redistribute = True
elif len(notes_in_chord) == 1:
# there is only one note left, so it's no longer a chord
chord_when = note_container.getAttribute('when').value
notes_in_chord[0].addAttribute('when', chord_when)
layer.addChildBefore(note_container, notes_in_chord[0])
layer.removeChild(note_container)
else:
# remove timestamp from timeline
when_id = note.getAttribute('when').value
when = self.mei_doc.getElementById(when_id)
when.getParent().removeChild(when)
self.redistribute = True
def _redistribute(self):
'''
Redistribute notes in the measures to match the 4/4 time signature
'''
layers = self.mei_doc.getElementsByName('layer')
note_events = []
for l in layers:
note_events.extend(l.getChildren())
# remove all measures
for m in self.mei_doc.getElementsByName('measure'):
m.getParent().removeChild(m)
section = self.mei_doc.getElementsByName('section')[0]
score_def = self.mei_doc.getElementsByName('scoreDef')[0]
meter_count = int(score_def.getAttribute('meter.count').value)
# insert the note events again
note_container = None
for i, note_event in enumerate(note_events):
if i % meter_count == 0:
measure = MeiElement('measure')
measure.addAttribute('n', str(int(i / meter_count + 1)))
staff = MeiElement('staff')
staff.addAttribute('n', '1')
layer = MeiElement('layer')
layer.addAttribute('n', '1')
section.addChild(measure)
measure.addChild(staff)
staff.addChild(layer)
note_container = layer
note_container.addChild(note_event)