"""Audio output interface."""
import subprocess
import tempfile
from pathlib import Path
from typing import TYPE_CHECKING, Optional, Union
import numpy as np
from numpy import ndarray
from ..external import get_musescore_soundfont_path
from .midi import write_midi
if TYPE_CHECKING:
from ..music import Music
def _check_soundfont(soundfont_path):
if soundfont_path is None:
soundfont_path = get_musescore_soundfont_path()
else:
soundfont_path = Path(soundfont_path)
if not soundfont_path.exists():
raise RuntimeError(
"Soundfont not found. Please download it by "
"`muspy.download_musescore_soundfont()`."
)
return soundfont_path
[docs]def synthesize(
music: "Music",
soundfont_path: Optional[Union[str, Path]] = None,
rate: int = 44100,
) -> ndarray:
"""Synthesize a Music object to raw audio.
Parameters
----------
music : :class:`muspy.Music`
Music object to write.
soundfont_path : str or Path, optional
Path to the soundfount file. Defaults to the path to the
downloaded MuseScore General soundfont.
rate : int
Sample rate (in samples per sec). Defaults to 44100.
Returns
-------
ndarray, dtype=int16, shape=(?, 2)
Synthesized waveform.
"""
# Check soundfont
soundfont_path = _check_soundfont(soundfont_path)
# Create a temporary directory
with tempfile.TemporaryDirectory() as temp_dir:
# Write the Music object to a temporary MIDI file
midi_path = Path(temp_dir) / "temp.mid"
write_midi(midi_path, music)
# Synthesize the MIDI file using fluidsynth
result = subprocess.run(
[
"fluidsynth",
"-T",
"raw",
"-F-",
"-r",
str(rate),
"-i",
str(soundfont_path),
str(midi_path),
],
check=True,
stdout=subprocess.PIPE,
)
# Decode bytes to waveform
waveform = np.frombuffer(result.stdout, np.int16).reshape(-1, 2)
return waveform
[docs]def write_audio(
path: Union[str, Path],
music: "Music",
soundfont_path: Optional[Union[str, Path]] = None,
rate: int = 44100,
audio_format: Optional[str] = None,
):
"""Write a Music object to an audio file.
Supported formats include WAV, AIFF, FLAC and OGA.
Parameters
----------
path : str or Path
Path to write the audio file.
music : :class:`muspy.Music`
Music object to write.
soundfont_path : str or Path, optional
Path to the soundfount file. Defaults to the path to the
downloaded MuseScore General soundfont.
rate : int
Sample rate (in samples per sec). Defaults to 44100.
audio_format : str, {'wav', 'aiff', 'flac', 'oga'}, optional
File format to write. If None, infer it from the extension.
"""
if audio_format is None:
audio_format = "auto"
# Check soundfont
soundfont_path = _check_soundfont(soundfont_path)
# Create a temporary directory
with tempfile.TemporaryDirectory() as temp_dir:
# Write the Music object to a temporary MIDI file
midi_path = Path(temp_dir) / "temp.mid"
write_midi(midi_path, music)
# Synthesize the MIDI file using fluidsynth
subprocess.run(
[
"fluidsynth",
"-ni",
"-F",
str(path),
"-T",
audio_format,
"-r",
str(rate),
str(soundfont_path),
str(midi_path),
],
check=True,
stdout=subprocess.DEVNULL,
)