| """Source-time fallback contracts on a known hum-like signal and plain noise.""" |
|
|
| from __future__ import annotations |
|
|
| from pathlib import Path |
| import tempfile |
| import unittest |
|
|
|
|
| class F0FallbackTest(unittest.TestCase): |
| def test_short_stable_note_survives_sheet_sage_empty_melody(self): |
| import numpy as np |
| import pretty_midi |
| import soundfile as sf |
| from f0_fallback import transcribe_f0 |
|
|
| rate = 24000 |
| wave = np.zeros(round(.6 * rate), dtype="float32") |
| t = np.arange(round(.48 * rate)) / rate |
| wave[round(.08 * rate):round(.56 * rate)] = .12 * np.sin(2 * np.pi * 261.626 * t) |
| with tempfile.TemporaryDirectory() as directory: |
| source, target = (Path(directory) / name for name in ("hum.wav", "notes.mid")) |
| sf.write(source, wave, rate) |
| self.assertEqual(transcribe_f0(source, target), 1) |
| note = pretty_midi.PrettyMIDI(str(target)).instruments[0].notes[0] |
| self.assertEqual(note.pitch, 60) |
| self.assertAlmostEqual(note.start, .08, delta=.05) |
| self.assertAlmostEqual(note.end, .56, delta=.05) |
|
|
| def test_unpitched_noise_does_not_create_midi(self): |
| import numpy as np |
| import soundfile as sf |
| from f0_fallback import transcribe_f0 |
|
|
| with tempfile.TemporaryDirectory() as directory: |
| source, target = (Path(directory) / name for name in ("noise.wav", "notes.mid")) |
| sf.write(source, np.random.default_rng(20260926).normal(0, .02, 72000), 24000) |
| with self.assertRaisesRegex(ValueError, "устойчивую высоту"): |
| transcribe_f0(source, target) |
| self.assertFalse(target.exists()) |
|
|
| def test_glide_stays_one_note_but_connected_syllables_retrigger(self): |
| import numpy as np |
| import pretty_midi |
| import soundfile as sf |
| from f0_fallback import transcribe_f0 |
|
|
| rate = 24000 |
| times = np.arange(round(2.5 * rate)) / rate |
| active = (times >= .2) & (times < 2.2) |
| for name in ("glide", "repeats"): |
| pitch = np.linspace(57, 62, active.sum()) if name == "glide" else np.full(active.sum(), 57) |
| frequency = 440 * 2 ** ((pitch - 69) / 12) |
| phase = 2 * np.pi * np.cumsum(frequency) / rate |
| signal = np.zeros(len(times), dtype=np.float32) |
| signal[active] = .13 * (np.sin(phase) + .28 * np.sin(2 * phase)) |
| if name == "repeats": |
| rng = np.random.default_rng(818) |
| for boundary in (.8, 1.5): |
| center = round(boundary * rate) |
| width = round(.035 * rate) |
| indices = np.arange(-width, width) |
| dip = .82 * np.exp(-.5 * (indices / (width / 2.5)) ** 2) |
| signal[center - width:center + width] *= 1 - dip |
| signal[center:center + round(.018 * rate)] += rng.normal( |
| 0, .018, round(.018 * rate)).astype(np.float32) |
| with self.subTest(name=name), tempfile.TemporaryDirectory() as directory: |
| source, target = (Path(directory) / filename for filename in ("hum.wav", "notes.mid")) |
| sf.write(source, signal, rate) |
| expected = 1 if name == "glide" else 3 |
| self.assertEqual(transcribe_f0(source, target), expected) |
| notes = pretty_midi.PrettyMIDI(str(target)).instruments[0].notes |
| if name == "repeats": |
| for note, start in zip(notes, (.2, .8, 1.5)): |
| self.assertEqual(note.pitch, 57) |
| self.assertAlmostEqual(note.start, start, delta=.06) |
|
|
