fix loading of multi-channel sound

stimuli/audio/_base.py

@@ -86,10 +86,9 @@ def _set_times(self) -> None:
  @abstractmethod
  def _set_signal(self, signal: NDArray) -> None:
  """Set the signal array."""
- signal = np.vstack([signal] * self._n_channels).T
  if self._window is not None:
  assert self._window.size == signal.shape[0] # sanity-check
- signal = np.multiply(signal, self._window[:, np.newaxis])
+ signal = signal * self._window[:, np.newaxis]
  assert self._volume.ndim == 1 # sanity-check
  assert self._volume.size == self._n_channels # sanity-check
  signal = np.ascontiguousarray(signal * self._volume / 100, dtype=np.float32)

stimuli/audio/am.py

@@ -105,6 +105,7 @@ def _set_signal(self) -> None:
  2 * np.pi * self._frequency_carrier * self._times
  )
  signal /= np.max(np.abs(signal)) # normalize
+ signal = np.vstack([signal] * self._n_channels).T
  super()._set_signal(signal)
 
  @property

stimuli/audio/noise.py

@@ -85,6 +85,7 @@ def _set_signal(self) -> None:
  S /= np.sqrt(np.mean(S**2))
  signal = np.fft.irfft(dft * S)
  signal /= np.max(np.abs(signal)) # normalize
+ signal = np.vstack([signal] * self._n_channels).T
  super()._set_signal(signal)
  # make sure we have the correct times as the rFFT and irFFT could get us off
  if self._times.size != self._signal.size:

stimuli/audio/tests/test_base.py

@@ -2,9 +2,11 @@
 
 import numpy as np
 import pytest
+import sounddevice as sd
 from numpy.testing import assert_allclose
+from scipy.io import wavfile
 
-from stimuli.audio import Noise, SoundAM, Tone
+from stimuli.audio import Noise, Sound, SoundAM, Tone
 from stimuli.audio._base import _check_duration, _ensure_volume, _ensure_window
 
 
@@ -127,3 +129,34 @@ def test_ensure_window():
 
  window = _ensure_window(None, 101)
  assert window is None
+
+
+@pytest.mark.parametrize(
+ ("sound"),
+ [
+ (Tone, dict(frequency=440)),
+ (Noise, dict(color="white")),
+ (
+ SoundAM,
+ dict(frequency_carrier=1000, frequency_modulation=40, method="dsbsc"),
+ ),
+ ],
+)
+def test_invalid_n_channels(sound):
+ """Test invalid number of channels."""
+ with pytest.raises(ValueError, match="The number of channels must be"):
+ sound = sound[0](volume=10, duration=1, n_channels=0, **sound[1])
+
+
+def test_window(tmp_path):
+ """Test applying a window the the sound."""
+ sfreq = int(sd.query_devices()[sd.default.device["output"]]["default_samplerate"])
+ data = np.ones((sfreq, 2)) # stereo
+ fname = tmp_path / "test.wav"
+ wavfile.write(fname, sfreq, data)
+ sound = Sound(fname)
+ window = np.zeros(sound.times.size, dtype=np.float32)
+ window[::10] = 1
+ sound.window = window
+ assert_allclose(sound.signal[::10, :], 1)
+ assert_allclose(sound.signal, data * window[:, np.newaxis])

stimuli/audio/tests/test_sound.py

@@ -9,13 +9,13 @@ def test_sound_io_mono(tmp_path):
  sound = Noise("pink", volume=100, duration=0.5)
  sound.save(tmp_path / "test.wav")
  sound_loaded = Sound(tmp_path / "test.wav")
- assert_allclose(sound.signal, sound_loaded.signal)
+ assert_allclose(sound.signal.squeeze(), sound_loaded.signal)
 
  sound = Noise("pink", volume=50, duration=0.5)
  sound.save(tmp_path / "test.wav", overwrite=True)
  sound_loaded = Sound(tmp_path / "test.wav")
  sound_loaded.volume = 50
- assert_allclose(sound.signal, sound_loaded.signal)
+ assert_allclose(sound.signal.squeeze(), sound_loaded.signal)
  # test representation
  assert str(tmp_path / "test.wav") in repr(sound_loaded)
  # test duration setter

stimuli/audio/tone.py

@@ -68,6 +68,7 @@ def __repr__(self) -> str:
  def _set_signal(self) -> None:
  signal = np.sin(2 * np.pi * self._frequency * self._times, dtype=np.float32)
  signal /= np.max(np.abs(signal)) # normalize
+ signal = np.vstack([signal] * self._n_channels).T
  super()._set_signal(signal)
 
  @property