def _do_spec(self):
if self._signal is None or len(self._signal) == 0:
self.set_data(np.array([[0.5]]))
return
#if len(self._signal) / self._sr > 30:
num_steps = 1000
if len(self._signal) < num_steps:
num_steps = len(self._signal)
step_samp = int(len(self._signal)/ num_steps)
#if step_samp < 28:
# step_samp = 28
# step = step_samp / self._sr
#self._n_fft = 512
#window = partial(gaussian, std = 250/12)
if self._window == 'gaussian':
window = partial(gaussian, std = 0.45*(self._win_len)/2)
else:
window = None
#import matplotlib.pyplot as plt
#plt.plot(window(250))
#plt.show()
data = stft(self._signal, self._n_fft, step_samp, center = True, win_length = self._win_len, window = window)
data = np.abs(data)
data = 20 * np.log10(data) if self._color_scale == 'log' else data
self.set_data(data)
def generate_spectrogram(signal, sr, color_scale='log'):
n_fft = 256
# if len(self._signal) / self._sr > 30:
window_length = 0.005
win_len = int(window_length * sr)
if win_len > n_fft:
n_fft = win_len
num_steps = 500
if len(signal) < num_steps:
num_steps = len(signal)
step_samp = int(len(signal) / num_steps)
time_step = step_samp / sr
freq_step = sr / n_fft
# if step_samp < 28:
# step_samp = 28
# step = step_samp / self._sr
# self._n_fft = 512
# window = partial(gaussian, std = 250/12)
window = 'gaussian'
# win_len = None
if window == 'gaussian':
window = partial(gaussian, std=0.45 * (win_len) / 2)
data = stft(signal,
n_fft,
step_samp,
center=True,
win_length=win_len,
window=window)
data = np.abs(data)
data = 20 * np.log10(data) if color_scale == 'log' else data
return data, time_step, freq_step
def audio_to_data(signal):
if config.silence_thr_db is not None:
signal, _ = trim(signal,
config.silence_thr_db,
frame_length=config.fft_bins,
hop_length=config.fft_hop_len)
spec = abs(
stft(signal, config.fft_bins, config.fft_hop_len,
config.fft_window_len))
# mfccs = mfcc(signal, config.sample_rate, n_mfcc=config.mfcc_bins)
# chroma = chroma_stft(signal, config.sample_rate, n_fft=config.fft_bins, hop_length=config.fft_hop_len, win_length=config.fft_window_len)
# show(specshow(spec, sr=config.sample_rate, hop_length=config.fft_hop_len))
# show(specshow(mfccs, sr=config.sample_rate, hop_length=config.fft_hop_len))
# show(plot(chroma))
vector = deepcopy(spec)
print('\tmax min initially:', max(vector), min(vector))
vector = amplitude_to_db(vector)
print('\tmax min in db:', max(vector), min(vector))
# vector = concatenate([vector, chroma], 0)
vector = vector.T
print('\tfinal vector shape:', vector.shape)
return vector
def process_signal(self, signal):
ft = np.abs(stft(signal, n_fft=self.window_size, hop_length=self.window_stride, window='hann'))
mel = melspectrogram(sr=self.sample_rate,S=ft)
mfccs = mfcc( sr=self.sample_rate, n_mfcc=self.num_mfccs,S=mel)
deltas= delta(mfccs)
delta_deltas= delta(mfccs,order=2)
return mfccs, deltas, delta_deltas
def generate_spectrogram(signal, sr, log_color_scale=True):
"""
Generate a spectrogram
Parameters
----------
signal : numpy.array
Signal to generate spectrogram from
sr : int
Sample rate of the signal
log_color_scale : bool
Flag to make the color scale logarithmic
Returns
-------
numpy.array
Spectrogram data
float
Time step between frames
float
Frequency step between bins
"""
n_fft = 256
# if len(self._signal) / self._sr > 30:
window_length = 0.005
win_len = int(window_length * sr)
if win_len > n_fft:
n_fft = win_len
num_steps = 500
if len(signal) < num_steps:
num_steps = len(signal)
step_samp = int(len(signal) / num_steps)
time_step = step_samp / sr
freq_step = sr / n_fft
# if step_samp < 28:
# step_samp = 28
# step = step_samp / self._sr
# self._n_fft = 512
# window = partial(gaussian, std = 250/12)
window = 'gaussian'
# win_len = None
if window == 'gaussian':
window = partial(gaussian, std=0.45 * win_len / 2)
data = stft(signal,
n_fft,
step_samp,
center=True,
win_length=win_len,
window=window)
data = np.abs(data)
if log_color_scale:
data = 20 * np.log10(data)
return data, time_step, freq_step
def __cqt_response(y, n_fft, hop_length, fft_basis, mode):
'''Compute the filter response with a target STFT hop.'''
# Compute the STFT matrix
D = stft(y,
n_fft=n_fft,
hop_length=hop_length,
window='ones',
pad_mode=mode)
# And filter response energy
return fft_basis.dot(D)
def melspectrogram(y=None,
sr=16000,
n_fft=400,
hop_length=160,
power=2.0,
**kwargs):
"""Compute a mel-scaled spectrogram.
If a spectrogram input `S` is provided, then it is mapped directly onto
the mel basis `mel_f` by `mel_f.dot(S)`.
If a time-series input `y, sr` is provided, then its magnitude spectrogram
`S` is first computed, and then mapped onto the mel scale by
`mel_f.dot(S**power)`. By default, `power=2` operates on a power spectrum.
Parameters
----------
y : np.ndarray [shape=(n,)] or None
audio time-series
sr : number > 0 [scalar]
sampling rate of `y`
n_fft : int > 0 [scalar]
length of the FFT window
hop_length : int > 0 [scalar]
number of samples between successive frames.
See `librosa.core.stft`
power : float > 0 [scalar]
Exponent for the magnitude melspectrogram.
e.g., 1 for energy, 2 for power, etc.
kwargs : additional keyword arguments
Mel filter bank parameters.
See `librosa.filters.mel` for details.
Returns
-------
S : np.ndarray [shape=(n_mels, t)]
Mel spectrogram
"""
# Compute a magnitude spectrogram from input
S = np.abs(stft(y, n_fft=n_fft, hop_length=hop_length,
center=False))**power
# Build a Mel filter
mel_basis = filters.mel(sr, n_fft, **kwargs)
return np.dot(mel_basis, S)
def librosa_compute_spec(y=None,
sr=1600,
S=None,
n_fft=2048,
hop_length=512,
power=1):
if S is not None:
# Infer n_fft from spectrogram shape
n_fft = 2 * (S.shape[0] - 1)
else:
# Otherwise, compute a magnitude spectrogram from input
# 计算的幅度普, 希望abs, 然后在取 power次方
S = np.abs(stft(y, n_fft=n_fft, hop_length=hop_length))**power
return S, n_fft
def log_energy(y, n_fft=400, hop_length=160):
power_spectrum = np.abs(
stft(y, n_fft=n_fft, hop_length=hop_length, center=False))**2
log_E = 10 * np.log10(sum(power_spectrum)) # in dB
return log_E
def pseudo_cqt(y,
sr=22050,
hop_length=512,
fmin=None,
n_bins=84,
bins_per_octave=12,
tuning=0.0,
filter_scale=1,
norm=1,
sparsity=0.01,
window='hann',
scale=True,
pad_mode='reflect'):
'''Compute the pseudo constant-Q transform of an audio signal.
This uses a single fft size that is the smallest power of 2 that is greater
than or equal to the max of:
1. The longest CQT filter
2. 2x the hop_length
Parameters
----------
y : np.ndarray [shape=(n,)]
audio time series
sr : number > 0 [scalar]
sampling rate of `y`
hop_length : int > 0 [scalar]
number of samples between successive CQT columns.
fmin : float > 0 [scalar]
Minimum frequency. Defaults to C1 ~= 32.70 Hz
n_bins : int > 0 [scalar]
Number of frequency bins, starting at `fmin`
bins_per_octave : int > 0 [scalar]
Number of bins per octave
tuning : None or float in `[-0.5, 0.5)`
Tuning offset in fractions of a bin (cents).
If `None`, tuning will be automatically estimated from the signal.
filter_scale : float > 0
Filter filter_scale factor. Larger values use longer windows.
sparsity : float in [0, 1)
Sparsify the CQT basis by discarding up to `sparsity`
fraction of the energy in each basis.
Set `sparsity=0` to disable sparsification.
window : str, tuple, number, or function
Window specification for the basis filters.
See `filters.get_window` for details.
pad_mode : string
Padding mode for centered frame analysis.
See also: `librosa.core.stft` and `np.pad`.
Returns
-------
CQT : np.ndarray [shape=(n_bins, t), dtype=np.float]
Pseudo Constant-Q energy for each frequency at each time.
Raises
------
ParameterError
If `hop_length` is not an integer multiple of
`2**(n_bins / bins_per_octave)`
Or if `y` is too short to support the frequency range of the CQT.
Notes
-----
This function caches at level 20.
'''
if fmin is None:
# C1 by default
fmin = note_to_hz('C1')
if tuning is None:
tuning = estimate_tuning(y=y, sr=sr)
fft_basis, n_fft, _ = __cqt_filter_fft(sr,
fmin,
n_bins,
bins_per_octave,
tuning,
filter_scale,
norm,
sparsity,
hop_length=hop_length,
window=window)
fft_basis = np.abs(fft_basis)
# Compute the magnitude STFT with Hann window
D = np.abs(stft(y, n_fft=n_fft, hop_length=hop_length, pad_mode=pad_mode))
# Project onto the pseudo-cqt basis
C = fft_basis.dot(D)
if scale:
C /= np.sqrt(n_fft)
else:
lengths = filters.constant_q_lengths(sr,
fmin,
n_bins=n_bins,
bins_per_octave=bins_per_octave,
tuning=tuning,
window=window,
filter_scale=filter_scale)
C *= np.sqrt(lengths[:, np.newaxis] / n_fft)
return C
def main():
files = glob(
config.data_path +
'/*.wav') # + glob('data/*.mp3') # try ffmpeg -i input.mp3 output.wav
if not config.frequencies_to_pick:
# gather initial info from all files
frequency_strengths = zeros(len(config.frequencies_of_bins))
for file in files:
signal = load(file, config.sample_rate)[0]
spec = abs(
stft(signal, config.fft_bins, config.fft_hop_len,
config.fft_window_len))
# print('\tmax min initially:', max(spec), min(spec))
# show(specshow(spec, sr=config.sample_rate, hop_length=config.fft_hop_len))
frequency_strengths += spec.sum(1) / spec.shape[1]
max_strength = max(frequency_strengths)
strength_thr = max_strength / config.frequency_strength_thr
band_low_hz = 999_999
band_high_hz = -1
for frequency, strength in zip(config.frequencies_of_bins,
frequency_strengths):
if strength >= strength_thr:
config.frequencies_to_pick.append(frequency)
if frequency < band_low_hz: band_low_hz = frequency
if frequency > band_high_hz: band_low_hz = frequency
# spec = cat([spec[config.frequencies_of_bins.index(i),:] for i in config.frequencies_to_pick], 0)
# print('\tmax min after bandpass:'******'with bandpass, timestep size: {len(config.frequencies_of_bins)} -> {len(config.frequencies_to_pick)}'
)
print(
f'copy paste this line into frequencies_to_pick @ config: \n{config.frequencies_to_pick}'
)
# proceed to separately processing each file
converted = []
for file_id, file in enumerate(files):
print(f'reading: {file}')
song_id = [0 if i == file_id else 1 for i in range(len(files))]
# analysis
signal, sample_rate = load(file, config.sample_rate)
data, meta = audio_to_data(signal, song_id)
converted.append([data, meta])
# synthesis
signal_recons = data_to_audio(data, meta)
write(f'{file.split("/")[-1]}_{file_id}.wav', config.sample_rate,
signal_recons)
signal_recons, sample_rate = load(
f'{file.split("/")[-1]}_{file_id}.wav', config.sample_rate)
pickle_save(converted, config.data_path + '.pk')
print('saved data.')
def audio_to_data(signal, song_id):
meta = [song_id]
if config.silence_thr_db:
signal, _ = trim(signal,
config.silence_thr_db,
frame_length=config.fft_bins,
hop_length=config.fft_hop_len)
spec = abs(
stft(signal, config.fft_bins, config.fft_hop_len,
config.fft_window_len))
# mfccs = mfcc(signal, config.sample_rate, n_mfcc=config.mfcc_bins)
# chroma = chroma_stft(signal, config.sample_rate, n_fft=config.fft_bins, hop_length=config.fft_hop_len, win_length=config.fft_window_len)
# rows-frequencies cols-times
# show(specshow(spec, sr=config.sample_rate, hop_length=config.fft_hop_len))
# show(specshow(mfccs, sr=config.sample_rate, hop_length=config.fft_hop_len))
# show(plot(chroma))
spec_mod = deepcopy(spec)
print('\tmax min initially:', max(spec_mod), min(spec_mod))
spec_mod = stack([
spec_mod[config.frequencies_of_bins.index(i), :]
for i in config.frequencies_to_pick
], 0)
print('\tmax min after bandpass:'******'\tmax min in db:', max(spec_mod), min(spec_mod))
# spec_mod = clip(spec_mod, config.amp_min_thr_db, config.amp_max_thr_db)
# print('db clipped.')
if config.zscore_scale:
mean = spec_mod.mean()
std = spec_mod.std()
spec_mod -= mean
spec_mod /= std
print('\tmax min after std:', max(spec_mod), min(spec_mod))
scale = max([abs(max(spec_mod)), abs(min(spec_mod))])
spec_mod /= scale
meta.extend([mean, std, scale])
elif config.minmax_scale:
spec_min = min(spec_mod)
spec_max = max(spec_mod)
spec_mod -= spec_min
spec_mod /= spec_max - spec_min
print('\tmax min after min/max:', max(spec_mod), min(spec_mod))
meta.extend([spec_min, spec_max])
elif config.log_scale:
spec_mod = log(spec_mod + 1e-10)
print('\tmax min after log:', max(spec_mod), min(spec_mod))
vector = spec_mod
# vector = concatenate([vector, chroma], 0)
vector = vector.T # now first index time, second index frequency
print('\tfinal vector shape:', vector.shape)
return vector, meta
