def _convert_array2song(self, array):
""" Create a new song from a numpy array
A note will be created for each non empty case of the array. The song will contain a single track, and use the
default beats_per_tick as midi resolution
For now, the changes of tempo are ignored. Only 4/4 is supported.
Warning: All note have the same duration, the default value defined in music.Note
Args:
np.array: the numpy array (Warning: could be a array of int or float containing the prediction before the sigmoid)
Return:
song (Song): The song to convert
"""
new_song = music.Song()
main_track = music.Track()
scale = self._get_scale(new_song)
for index, x in np.ndenumerate(array): # Add some notes
if x > 1e-12: # Note added (TODO: What should be the condition, =1 ? sigmoid>0.5 ?)
new_note = music.Note()
new_note.set_relative_note(index[0])
new_note.tick = index[1] * scale # Absolute time in tick from the beginning
main_track.notes.append(new_note)
new_song.tracks.append(main_track)
return new_song
def get_batches_test_old(
self
): # TODO: This is the old version. Ideally should use the version above
""" Return the batches which initiate the RNN when generating
The initial batches are loaded from a json file containing the first notes of the song. The note values
are the standard midi ones. Here is an examples of an initiator file:
```
{"initiator":[
{"name":"Simple_C4",
"seq":[
{"notes":[60]}
]},
{"name":"some_chords",
"seq":[
{"notes":[60,64]}
{"notes":[66,68,71]}
{"notes":[60,64]}
]}
]}
```
Return:
List[Batch], List[str]: The generated batches with the associated names
"""
assert self.args.batch_size == 1
batches = []
names = []
with open(self.TEST_INIT_FILE) as init_file:
initiators = json.load(init_file)
for initiator in initiators['initiator']:
raw_song = music.Song()
main_track = music.Track()
current_tick = 0
for seq in initiator['seq']: # We add a few notes
for note_pitch in seq['notes']:
new_note = music.Note()
new_note.note = note_pitch
new_note.tick = current_tick
main_track.notes.append(new_note)
current_tick += 1
raw_song.tracks.append(main_track)
raw_song.normalize(inverse=True)
batch = self.batch_builder.process_batch(raw_song)
names.append(initiator['name'])
batches.append(batch)
return batches, names
def reconstruct_song(self, rel_song):
""" Reconstruct the original raw song from the preprocessed data
See parent class for details
Some information will be lost compare to the original song:
* Only one track left
* Original tempo lost
Args:
rel_song (RelativeSong): the song to reconstruct
Return:
Song: the reconstructed song
"""
raw_song = music.Song()
main_track = music.Track()
prev_note = rel_song.first_note
main_track.notes.append(rel_song.first_note)
current_tick = rel_song.first_note.tick
for next_note in rel_song.notes:
# Case of separator
if next_note.pitch_class is None:
current_tick += 1
continue
# Adding the new note
new_note = music.Note()
# * Note
if Relative.NOTE_ABSOLUTE:
new_note.note = Relative.BASELINE_OFFSET + next_note.pitch_class
else:
new_note.note = Relative.BASELINE_OFFSET + (
(prev_note.note - Relative.BASELINE_OFFSET) +
next_note.pitch_class) % Relative.NB_NOTES_SCALE
# * Tick
if Relative.HAS_EMPTY:
new_note.tick = current_tick
else:
new_note.tick = prev_note.tick + next_note.prev_tick
# * Scale
# ...
main_track.notes.append(new_note)
prev_note = new_note
raw_song.tracks.append(main_track)
raw_song.normalize(inverse=True)
return raw_song
def load_file(filename):
""" Extract data from midi file
Args:
filename (str): a valid midi file
Return:
Song: a song object containing the tracks and melody
"""
# Load in the MIDI data using the midi module
midi_data = mido.MidiFile(filename)
# Get header values
# 3 midi types:
# * type 0 (single track): all messages are saved in one multi-channel track
# * type 1 (synchronous): all tracks start at the same time
# * type 2 (asynchronous): each track is independent of the others
# Division (ticks per beat notes or SMTPE timecode)
# If negative (first byte=1), the mode is SMTPE timecode (unsupported)
# 1 MIDI clock = 1 beat = 1 quarter note
# Assert
if midi_data.type != 1:
raise MidiInvalidException('Only type 1 supported ({} given)'.format(midi_data.type))
if not 0 < midi_data.ticks_per_beat < 128:
raise MidiInvalidException('SMTPE timecode not supported ({} given)'.format(midi_data.ticks_per_beat))
# TODO: Support at least for type 0
# Get tracks messages
# The tracks are a mix of meta messages, which determine the tempo and signature, and note messages, which
# correspond to the melodie.
# Generally, the meta event are set at the beginning of each tracks. In format 1, these meta-events should be
# contained in the first track (known as 'Tempo Map').
# If not set, default parameters are:
# * time signature: 4/4
# * tempo: 120 beats per minute
# Each event contain begins by a delta time value, which correspond to the number of ticks from the previous
# event (0 for simultaneous event)
tempo_map = midi_data.tracks[0] # Will contains the tick scales
# TODO: smpte_offset
# Warning: The drums are filtered
# Merge tracks ? < Not when creating the dataset
#midi_data.tracks = [mido.merge_tracks(midi_data.tracks)] ??
new_song = music.Song()
new_song.ticks_per_beat = midi_data.ticks_per_beat
# TODO: Normalize the ticks per beats (same for all songs)
for message in tempo_map:
# TODO: Check we are only 4/4 (and there is no tempo changes ?)
if not isinstance(message, mido.MetaMessage):
raise MidiInvalidException('Tempo map should not contains notes')
if message.type in MidiConnector.META_INFO_TYPES:
pass
elif message.type == 'set_tempo':
new_song.tempo_map.append(message)
elif message.type in MidiConnector.META_TEMPO_TYPES: # We ignore the key signature and time_signature ?
pass
elif message.type == 'smpte_offset':
pass # TODO
else:
err_msg = 'Header track contains unsupported meta-message type ({})'.format(message.type)
raise MidiInvalidException(err_msg)
for i, track in enumerate(midi_data.tracks[1:]): # We ignore the tempo map
i += 1 # Warning: We have skipped the track 0 so shift the track id
#tqdm.write('Track {}: {}'.format(i, track.name))
new_track = music.Track()
buffer_notes = [] # Store the current notes (pressed but not released)
abs_tick = 0 # Absolute nb of ticks from the beginning of the track
for message in track:
abs_tick += message.time
if isinstance(message, mido.MetaMessage): # Lyrics, track name and other meta info
if message.type in MidiConnector.META_INFO_TYPES:
pass
elif message.type in MidiConnector.META_TEMPO_TYPES:
# TODO: Could be just a warning
raise MidiInvalidException('Track {} should not contain {}'.format(i, message.type))
else:
err_msg = 'Track {} contains unsupported meta-message type ({})'.format(i, message.type)
raise MidiInvalidException(err_msg)
# What about 'sequence_number', cue_marker ???
else: # Note event
if message.type == 'note_on' and message.velocity != 0: # Note added
new_note = music.Note()
new_note.tick = abs_tick
new_note.note = message.note
if message.channel+1 != i and message.channel+1 != MidiConnector.MIDI_CHANNEL_DRUMS: # Warning: Mido shift the channels (start at 0) # TODO: Channel management for type 0
raise MidiInvalidException('Notes belong to the wrong tracks ({} instead of {})'.format(i, message.channel)) # Warning: May not be an error (drums ?) but probably
buffer_notes.append(new_note)
elif message.type == 'note_off' or message.type == 'note_on': # Note released
for note in buffer_notes:
if note.note == message.note:
note.duration = abs_tick - note.tick
buffer_notes.remove(note)
new_track.notes.append(note)
elif message.type == 'program_change': # Instrument change
if not new_track.set_instrument(message):
# TODO: We should create another track with the new instrument
raise MidiInvalidException('Track {} as already a program defined'.format(i))
pass
elif message.type == 'control_change': # Damper pedal, mono/poly, channel volume,...
# Ignored
pass
elif message.type == 'aftertouch': # Signal send after a key has been press. What real effect ?
# Ignored ?
pass
elif message.type == 'pitchwheel': # Modulate the song
# Ignored
pass
else:
err_msg = 'Track {} contains unsupported message type ({})'.format(i, message)
raise MidiInvalidException(err_msg)
# Message read
# Track read
# Assert
if buffer_notes: # All notes should have ended
raise MidiInvalidException('Some notes ({}) did not ended'.format(len(buffer_notes)))
if len(new_track.notes) < MidiConnector.MINIMUM_TRACK_LENGTH:
#tqdm.write('Track {} ignored (too short): {} notes'.format(i, len(new_track.notes)))
continue
if new_track.is_drum:
#tqdm.write('Track {} ignored (is drum)'.format(i))
continue
new_song.tracks.append(new_track)
# All track read
if not new_song.tracks:
raise MidiInvalidException('Empty song. No track added')
return new_song