ref: b4445fb25f9c4bc904a4782f9ad8a4fa1afd2b79
dir: /python/demos/demo_wav2midi.py/
#! /usr/bin/env python
# Simple demo to extract notes from a sound file, and store them in a midi file
# using mido.
#
# Install mido: `pip instal mido`
#
# Documentation: https://mido.readthedocs.io/
import sys
from aubio import source, notes
from mido import Message, MetaMessage, MidiFile, MidiTrack, second2tick, bpm2tempo
if len(sys.argv) < 3:
print("Usage: %s <filename> <output> [samplerate]" % sys.argv[0])
sys.exit(1)
filename = sys.argv[1]
midioutput = sys.argv[2]
downsample = 1
samplerate = 44100 // downsample
if len( sys.argv ) > 3: samplerate = int(sys.argv[3])
win_s = 512 // downsample # fft size
hop_s = 256 // downsample # hop size
s = source(filename, samplerate, hop_s)
samplerate = s.samplerate
tolerance = 0.8
notes_o = notes("default", win_s, hop_s, samplerate)
print("%8s" % "time","[ start","vel","last ]")
# create a midi file
mid = MidiFile()
track = MidiTrack()
mid.tracks.append(track)
ticks_per_beat = mid.ticks_per_beat # default: 480
bpm = 120 # default midi tempo
tempo = bpm2tempo(bpm)
track.append(MetaMessage('set_tempo', tempo=tempo))
track.append(MetaMessage('time_signature', numerator=4, denominator=4))
def frames2tick(frames, samplerate=samplerate):
sec = frames / float(samplerate)
return int(second2tick(sec, ticks_per_beat, tempo))
last_time = 0
# total number of frames read
total_frames = 0
while True:
samples, read = s()
new_note = notes_o(samples)
if (new_note[0] != 0):
note_str = ' '.join(["%.2f" % i for i in new_note])
print("%.6f" % (total_frames/float(samplerate)), new_note)
delta = frames2tick(total_frames) - last_time
if new_note[2] > 0:
track.append(Message('note_off', note=int(new_note[2]),
velocity=127, time=0)
)
track.append(Message('note_on',
note=int(new_note[0]),
velocity=int(new_note[1]),
time=delta)
)
last_time = frames2tick(total_frames)
total_frames += read
if read < hop_s: break
mid.save(midioutput)