Spaces:
Building
on
T4
Building
on
T4
File size: 6,409 Bytes
1ea42dc |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 |
import PIL
import numpy as np
class MIDITokenizer:
def __init__(self):
self.vocab_size = 0
def allocate_ids(size):
ids = [self.vocab_size + i for i in range(size)]
self.vocab_size += size
return ids
self.pad_id = allocate_ids(1)[0]
self.bos_id = allocate_ids(1)[0]
self.eos_id = allocate_ids(1)[0]
self.events = {
"note": ["time1", "time2", "track", "duration", "channel", "pitch", "velocity"],
"patch_change": ["time1", "time2", "track", "channel", "patch"],
"control_change": ["time1", "time2", "track", "channel", "controller", "value"],
"set_tempo": ["time1", "time2", "track", "bpm"],
}
self.event_parameters = {
"time1": 128, "time2": 16, "duration": 2048, "track": 128, "channel": 16, "pitch": 128, "velocity": 128,
"patch": 128, "controller": 128, "value": 128, "bpm": 256
}
self.event_ids = {e: allocate_ids(1)[0] for e in self.events.keys()}
self.id_events = {i: e for e, i in self.event_ids.items()}
self.parameter_ids = {p: allocate_ids(s) for p, s in self.event_parameters.items()}
self.max_token_seq = max([len(ps) for ps in self.events.values()]) + 1
def tempo2bpm(self, tempo):
tempo = tempo / 10 ** 6 # us to s
bpm = 60 / tempo
return bpm
def bpm2tempo(self, bpm):
if bpm == 0:
bpm = 1
tempo = int((60 / bpm) * 10 ** 6)
return tempo
def tokenize(self, midi_score, add_bos_eos=True):
ticks_per_beat = midi_score[0]
event_list = {}
track_num = len(midi_score[1:])
for track_idx, track in enumerate(midi_score[1:129]):
for event in track:
t = round(16 * event[1] / ticks_per_beat)
new_event = [event[0], t // 16, t % 16, track_idx] + event[2:]
if event[0] == "note":
new_event[4] = max(1, round(16 * new_event[4] / ticks_per_beat))
elif event[0] == "set_tempo":
new_event[4] = int(self.tempo2bpm(new_event[4]))
key = hash(tuple(new_event[:-1]))
event_list[key] = new_event
event_list = list(event_list.values())
event_list = sorted(event_list, key=lambda e: (e[1] * 16 + e[2]) * track_num + e[3])
midi_seq = []
last_t1 = 0
for event in event_list:
name = event[0]
if name in self.event_ids:
params = event[1:]
cur_t1 = params[0]
params[0] = params[0] - last_t1
if not all([0 <= params[i] < self.event_parameters[p] for i, p in enumerate(self.events[name])]):
continue
tokens = [self.event_ids[name]] + [self.parameter_ids[p][params[i]]
for i, p in enumerate(self.events[name])]
tokens += [self.pad_id] * (self.max_token_seq - len(tokens))
midi_seq.append(tokens)
last_t1 = cur_t1
if add_bos_eos:
bos = [self.bos_id] + [self.pad_id] * (self.max_token_seq - 1)
eos = [self.eos_id] + [self.pad_id] * (self.max_token_seq - 1)
midi_seq = [bos] + midi_seq + [eos]
return midi_seq
def event2tokens(self, event):
name = event[0]
params = event[1:]
tokens = [self.event_ids[name]] + [self.parameter_ids[p][params[i]]
for i, p in enumerate(self.events[name])]
tokens += [self.pad_id] * (self.max_token_seq - len(tokens))
return tokens
def detokenize(self, midi_seq):
ticks_per_beat = 480
tracks_dict = {}
t1 = 0
for tokens in midi_seq:
if tokens[0] in self.id_events:
name = self.id_events[tokens[0]]
if len(tokens) <= len(self.events[name]):
continue
params = tokens[1:]
params = [params[i] - self.parameter_ids[p][0] for i, p in enumerate(self.events[name])]
if not all([0 <= params[i] < self.event_parameters[p] for i, p in enumerate(self.events[name])]):
continue
event = [name] + params
if name == "set_tempo":
event[4] = self.bpm2tempo(event[4])
if event[0] == "note":
event[4] = int(event[4] * ticks_per_beat / 16)
t1 += event[1]
t = t1 * 16 + event[2]
t = int(t * ticks_per_beat / 16)
track_idx = event[3]
if track_idx not in tracks_dict:
tracks_dict[track_idx] = []
tracks_dict[track_idx].append([event[0], t] + event[4:])
tracks = list(tracks_dict.values())
for i in range(len(tracks)):
track = tracks[i]
track = sorted(track, key=lambda e: e[1])
last_note_t = {}
for e in reversed(track):
if e[0] == "note":
t, d, c, p = e[1:5]
key = (c, p)
if key in last_note_t:
d = min(d, max(last_note_t[key] - t, 0)) # to avoid note overlap
last_note_t[key] = t
e[2] = d
tracks[i] = track
return [ticks_per_beat, *tracks]
def midi2img(self, midi_score):
ticks_per_beat = midi_score[0]
notes = []
max_time = 1
track_num = len(midi_score[1:])
for track_idx, track in enumerate(midi_score[1:]):
for event in track:
t = round(16 * event[1] / ticks_per_beat)
if event[0] == "note":
d = max(1, round(16 * event[2] / ticks_per_beat))
c, p = event[3:5]
max_time = max(max_time, t + d + 1)
notes.append((track_idx, c, p, t, d))
img = np.zeros((128, max_time, 3), dtype=np.uint8)
colors = {(i, j): np.random.randint(50, 256, 3) for i in range(track_num) for j in range(16)}
for note in notes:
tr, c, p, t, d = note
img[p, t: t + d] = colors[(tr, c)]
img = PIL.Image.fromarray(np.flip(img, 0))
return img
|