| import fluidsynth |
| import numpy as np |
|
|
|
|
| def synthesis(midi_opus, soundfont_path, sample_rate=44100): |
| ticks_per_beat = midi_opus[0] |
| event_list = [] |
| for track_idx, track in enumerate(midi_opus[1:]): |
| abs_t = 0 |
| for event in track: |
| abs_t += event[1] |
| event_new = [*event] |
| event_new[1] = abs_t |
| event_list.append(event_new) |
| event_list = sorted(event_list, key=lambda e: e[1]) |
|
|
| tempo = int((60 / 120) * 10 ** 6) |
| ss = np.empty((0, 2), dtype=np.int16) |
| fl = fluidsynth.Synth(samplerate=float(sample_rate)) |
| sfid = fl.sfload(soundfont_path) |
| last_t = 0 |
| for c in range(16): |
| fl.program_select(c, sfid, 128 if c == 9 else 0, 0) |
| for event in event_list: |
| name = event[0] |
| sample_len = int(((event[1] / ticks_per_beat) * tempo / (10 ** 6)) * sample_rate) |
| sample_len -= int(((last_t / ticks_per_beat) * tempo / (10 ** 6)) * sample_rate) |
| last_t = event[1] |
| if sample_len > 0: |
| sample = fl.get_samples(sample_len).reshape(sample_len, 2) |
| ss = np.concatenate([ss, sample]) |
| if name == "set_tempo": |
| tempo = event[2] |
| elif name == "patch_change": |
| c, p = event[2:4] |
| fl.program_select(c, sfid, 128 if c == 9 else 0, p) |
| elif name == "control_change": |
| c, cc, v = event[2:5] |
| fl.cc(c, cc, v) |
| elif name == "note_on" and event[3] > 0: |
| c, p, v = event[2:5] |
| fl.noteon(c, p, v) |
| elif name == "note_off" or (name == "note_on" and event[3] == 0): |
| c, p = event[2:4] |
| fl.noteoff(c, p) |
|
|
| fl.delete() |
| if ss.shape[0] > 0: |
| max_val = np.abs(ss).max() |
| if max_val != 0: |
| ss = (ss / max_val) * np.iinfo(np.int16).max |
| ss = ss.astype(np.int16) |
| return ss |
