def sounds_to_key_and_stream(sounds):
key = set()
stream = Stream()
for sound in sounds:
stream.add_sound(sound)
key.add(
KeySound(
frequency=sound.frequency,
duration=sound.duration,
volume=sound.volume,
)
)
return frozenset(key), stream
twinkle_twinkle_little_star = Stream()
current_time = 0
for phrase in twinkle_twinkle_little_star_notes:
for note, timing in zip(
phrase.split(" "), tinkle_twinkle_little_star_timings
):
duration = note_length * timing
twinkle_twinkle_little_star.add_sound(
Tone(
start=current_time,
duration=duration,
frequency=scientific_note_frequency(note),
overtones=[],
volume=0.4,
attack_seconds=0.1,
decay_seconds=0.1,
sustain_level=0.75,
release_seconds=0.2,
)
)
current_time += duration
def fuzzy_start(sounds):
for sound in sounds:
yield sound.delayed(
random.uniform(-note_length / 32.0, note_length / 32.0)
)
def build_stream_from_midi(filename):
mid = mido.MidiFile(filename)
merged_tracks = mido.merge_tracks(mid.tracks)
bpm = None
current_time = 0
active_notes = {
channel: defaultdict(list)
for channel in set(
msg.channel for msg in merged_tracks if "channel" in msg.dict())
}
stream = Stream()
for msg in merged_tracks:
if msg.type == "note_on" and msg.velocity == 0:
# turn a zero velocity note on into an equivalent note off
data = msg.dict()
data["type"] = "note_off"
msg = msg.from_dict(data)
if bpm is not None:
current_time += msg.time / mid.ticks_per_beat / bpm * 60
if msg.type == "set_tempo":
bpm = mido.tempo2bpm(msg.tempo)
elif msg.type == "note_on":
if bpm is None:
raise Exception(f"no tempo found before the first note")
active_notes[msg.channel][msg.note].append(
(current_time, msg.velocity))
elif msg.type == "note_off":
if not active_notes[msg.channel][msg.note]:
raise Exception(
f"notes: {active_notes}, disabling note: {msg}")
if current_time is None:
raise Exception(f"no tempo found before the first note")
if msg.velocity != 0:
raise Exception(
f"do not konw how to work with non-zero note_off velocity: {msg}"
)
started, initial_velocity = active_notes[msg.channel][
msg.note].pop()
if msg.channel == 2:
continue
duration = current_time - started
if duration > 5:
raise Exception(f"would have created a very long note: {msg}")
stream.add_sound(
Tone(
start=started,
duration=duration,
frequency=midi_note_frequency(msg.note),
overtones=[
Overtone(2, 0.5 * pi, 0.5),
Overtone(3, 0, 0.3),
Overtone(4, 0.25 * pi, 0.2),
Overtone(5, 0, 0.2),
],
volume=0.4 * initial_velocity / 127,
attack_seconds=0.1,
decay_seconds=0.1,
sustain_level=0.75,
release_seconds=0.1,
))
elif msg.type in (
"time_signature",
"key_signature",
"program_change",
"control_change",
"track_name",
"smpte_offset",
"midi_port",
"end_of_track",
):
continue
else:
raise Exception(f"unkown message: {msg}")
return stream
