def __compute_zscore(data: np.ndarray, axis: int = -1, clip: float = 3.0):
dims = data.ndim
data[data == np.inf] = np.nan
data[data == -np.inf] = np.nan
if axis is None:
length = 1
else:
if axis < 0:
axis += dims
length = data.shape[axis]
for i in range(length):
_slice = [i if j == axis else slice(None) for j in range(dims)]
sliced = data.__getitem__(_slice)
extremes = find_extreme_values(sliced)
score = (sliced - np.nanmedian(sliced[~extremes])) / np.nanstd(sliced[~extremes])
score = np.clip(score, -clip, clip)
epsilon = 1e-4
total_err = 1.0
avg = np.nanmean(score[~extremes])
sd = np.nanstd(score[~extremes])
z = (score - avg) / sd
trial = 0
while total_err > epsilon and trial < 3:
if (abs(z) >= clip).any():
z = np.clip(z, -clip, clip)
avg = np.nanmean(z)
std = np.nanstd(z)
total_err = abs(avg) + abs(std - 1)
z = (z - avg) / std
trial += 1
data.__setitem__(_slice, z)
return data
def destagger_array(a: np.ndarray, axis: int) -> np.ndarray:
"""
Staggers/destaggers an array along a given axis.
"""
dims = len(a.shape)
slices0 = tuple(
slice(0, -1) if i == axis else slice(None) for i in range(dims))
slices1 = tuple(
slice(1, None) if i == axis else slice(None) for i in range(dims))
a0 = a.__getitem__(slices0)
a1 = a.__getitem__(slices1)
aa = 0.5 * a0 + 0.5 * a1
return aa
def align_midi(audio_cqt: np.ndarray,
audio_times: np.ndarray,
full_synthesized_midi_path: str,
full_alignment_write_path: str,
alignment_parameters: Optional[AlignmentParameters] = None):
"""
Align audio (specified by CQT) to synthesized MIDI (specified by path), return path and score of the alignment
:param alignment_parameters: Parameters for alignment
:param audio_cqt: The CQT of the audio of the alignment
:param audio_times: Array of times of the audio (from compute_cqt function)
:param full_synthesized_midi_path: The path to the synthesized MIDI file
:param full_alignment_write_path: The path to write the alignment to
"""
# Make sure to have alignment parameters
if alignment_parameters is None:
alignment_parameters = AlignmentParameters()
# Open the synthesized midi file
midi_audio, _ = librosa.load(full_synthesized_midi_path,
sr=alignment_parameters.sampling_rate)
# Compute log-magnitude CQT of the synthesized midi file
midi_cqt, midi_times = _compute_cqt(midi_audio, alignment_parameters)
# Compute the distance matrix of the midi and audio CQTs, using cosine distance
distance_matrix = scipy.spatial.distance.cdist(midi_cqt, audio_cqt,
'cosine')
additive_penalty = float(np.median(np.ravel(distance_matrix)))
multiplicative_penalty = 1.
# Get lowest cost path in the distance matrix
p, q, score = _dtw(distance_matrix, alignment_parameters.gully,
additive_penalty, multiplicative_penalty)
# Compute MIDIAlignment
midi_alignment = MIDIAlignment(midi_times.__getitem__(p),
audio_times.__getitem__(q))
# Normalize by path length and the distance matrix sub-matrix within the path
score = score / len(p)
score = score / distance_matrix[p.min():p.max(), q.min():q.max()].mean()
# Write score
midi_name = fh.get_file_name_from_full_path(full_synthesized_midi_path)
decibel.import_export.midi_alignment_score_io.write_chord_alignment_score(
midi_name, score)
# Write alignment
decibel.import_export.midi_alignment_io.write_alignment_file(
midi_alignment, full_alignment_write_path)
