ref: 7c85c153c6e39b86bdb5fbc9925839b94684bef5
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)