def generate_chord_progression(mdl,
starting_chord,
length,
max_memory=4,
random_neighbors=False):
progression = ChordProgression(Chord(starting_chord))
current_chord = starting_chord
memory = []
top_k = 10
if max_memory > 0:
memory = [current_chord]
for i in range(0, length):
next_chord = current_chord
# print("current_chord: ", current_chord)
neighbors = mdl.get_nearest_neighbors(next_chord, top_k)
neighbor_chords = [n[1] for n in neighbors]
# print("\tneighbors:", neighbor_chords)
# choose random neighbor
if random_neighbors:
processed_neighbors = np.random.choice(neighbor_chords, top_k)
else:
processed_neighbors = neighbor_chords
if len(processed_neighbors):
# choose sequential neighbors
for neighbor in processed_neighbors:
if neighbor != next_chord and neighbor not in memory:
next_chord = neighbor
memory.append(next_chord)
if len(memory) >= max_memory:
memory.pop(0) # remove first element
# random_neighbors = np.random.choice(neighbor_chords, 1)
# print("\trandom_neighbors: ", random_neighbors)
# next_chord = random_neighbors[0]
current_chord = next_chord
if current_chord:
chrd = Chord(current_chord)
progression.append(chrd)
return progression
def get_chord_progression_from_file(f_name, debug=False):
"""
Takes a file name returns a chord progression
:return ChordProgression
"""
if debug:
print("processing: {}".format(f_name))
mlt = Multitrack()
try:
mlt.parse_midi(filename=f_name, binarized=True)
merged_mlt = mlt.get_merged_pianoroll(mode='max')
except:
print("unable to parse. skipping: {}".format(f_name))
return ChordProgression() # empty progression
chord_progression = ChordProgression([])
last_chord_change = 0
for i, x in enumerate(merged_mlt):
# print(x)
notes = np.where(x)
num_notes = np.sum(x)
if num_notes:
if num_notes > 1:
chord_notes = INT_TO_NOTE[notes[0] % 12]
chord_name = note_to_chord(chord_notes.tolist())
if chord_name:
chord = chord_name[0]
if len(chord_progression.chords
) == 0 or chord_progression.chords[-1] != chord:
# print("chord: ", notes[0], chord_notes, chord_name)
chord_progression.append(chord)
# else:
# print("note: ", notes[0])
# print(chord_progression)
return chord_progression
def test_append(self):
cp = ChordProgression(["C", "D", "E"])
cp.append("F")
self.assertEqual(len(cp), 4)
self.assertEqual(cp.chords[-1], Chord("F"))
