File size: 10,065 Bytes
9016314
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
'''
Copied from espnet: https://github.com/espnet/espnet/blob/master/espnet/transform/spectrogram.py
'''
import librosa
import numpy as np

# for sing + acc.
def AWeightingLoudness_SingAcc(x, sr, n_fft, n_shift, win_length=None, window='hann', center=True, pad_mode='reflect'):
    assert x.ndim == 1, 'The audio has %d channels, but so far we only support single-channel audios.' %(x.ndim)
    # [Freq, Time]
    mag_stft = np.abs(stft(x, n_fft, n_shift, win_length, window, center, pad_mode).T)

    freq_axis = librosa.fft_frequencies(sr=sr, n_fft=n_fft)
    perceptual_stft = librosa.perceptual_weighting(mag_stft**2, freq_axis, ref=1)
    perceptual_loudness = np.log10(np.sum(np.power(10, perceptual_stft/10), axis=0)+1e-5)

    return perceptual_loudness

# Extract Log-Scaled A-Weighting Loudness from Audio. Added by Xu Li.
def AWeightingLoudness(x, sr, n_fft, n_shift, win_length=None, window='hann', center=True, pad_mode='reflect'):
    assert x.ndim == 1, 'The audio has %d channels, but so far we only support single-channel audios.' %(x.ndim)
    # [Freq, Time]
    mag_stft = np.abs(stft(x, n_fft, n_shift, win_length, window, center, pad_mode).T)

    freq_axis = librosa.fft_frequencies(sr=sr, n_fft=n_fft)
    perceptual_stft = librosa.perceptual_weighting(mag_stft**2, freq_axis, ref=1)
    perceptual_loudness = np.log10(np.mean(np.power(10, perceptual_stft/10), axis=0)+1e-5)

    return perceptual_loudness

def VoicedAreaDetection(x, sr, n_fft, n_shift, win_length=None, window='hann', center=True, pad_mode='reflect', hi_freq=1000, energy_thres=0.5):
    assert x.ndim == 1, 'The audio has %d channels, but so far we only support single-channel audios.' %(x.ndim)
    # [Freq, Time]
    mag_stft = np.abs(stft(x, n_fft, n_shift, win_length, window, center, pad_mode).T)
    freq_axis = librosa.fft_frequencies(sr=sr, n_fft=n_fft)
    filtered_mag_stft = mag_stft[freq_axis <= hi_freq]
    loudness = np.log10(np.mean(np.power(10, filtered_mag_stft/10), axis=0)+1e-5)
    
    return loudness >= energy_thres


def stft(
    x, n_fft, n_shift, win_length=None, window="hann", center=True, pad_mode="reflect"
):
    # x: [Time, Channel]
    if x.ndim == 1:
        single_channel = True
        # x: [Time] -> [Time, Channel]
        x = x[:, None]
    else:
        single_channel = False
    x = x.astype(np.float32)

    # FIXME(kamo): librosa.stft can't use multi-channel?
    # x: [Time, Channel, Freq]
    x = np.stack(
        [
            librosa.stft(
                x[:, ch],
                n_fft=n_fft,
                hop_length=n_shift,
                win_length=win_length,
                window=window,
                center=center,
                pad_mode=pad_mode,
            ).T
            for ch in range(x.shape[1])
        ],
        axis=1,
    )

    if single_channel:
        # x: [Time, Channel, Freq] -> [Time, Freq]
        x = x[:, 0]
    return x


def istft(x, n_shift, win_length=None, window="hann", center=True):
    # x: [Time, Channel, Freq]
    if x.ndim == 2:
        single_channel = True
        # x: [Time, Freq] -> [Time, Channel, Freq]
        x = x[:, None, :]
    else:
        single_channel = False

    # x: [Time, Channel]
    x = np.stack(
        [
            librosa.istft(
                x[:, ch].T,  # [Time, Freq] -> [Freq, Time]
                hop_length=n_shift,
                win_length=win_length,
                window=window,
                center=center,
            )
            for ch in range(x.shape[1])
        ],
        axis=1,
    )

    if single_channel:
        # x: [Time, Channel] -> [Time]
        x = x[:, 0]
    return x


def stft2logmelspectrogram(x_stft, fs, n_mels, n_fft, fmin=None, fmax=None, eps=1e-10):
    # x_stft: (Time, Channel, Freq) or (Time, Freq)
    fmin = 0 if fmin is None else fmin
    fmax = fs / 2 if fmax is None else fmax

    # spc: (Time, Channel, Freq) or (Time, Freq)
    spc = np.abs(x_stft)
    # mel_basis: (Mel_freq, Freq)
    mel_basis = librosa.filters.mel(sr=fs, n_fft=n_fft, n_mels=n_mels, fmin=fmin, fmax=fmax)
    # lmspc: (Time, Channel, Mel_freq) or (Time, Mel_freq)
    lmspc = np.log10(np.maximum(eps, np.dot(spc, mel_basis.T)))

    return lmspc


def spectrogram(x, n_fft, n_shift, win_length=None, window="hann"):
    # x: (Time, Channel) -> spc: (Time, Channel, Freq)
    spc = np.abs(stft(x, n_fft, n_shift, win_length, window=window))
    return spc


def logmelspectrogram(
    x,
    fs,
    n_mels,
    n_fft,
    n_shift,
    win_length=None,
    window="hann",
    fmin=None,
    fmax=None,
    eps=1e-10,
    pad_mode="reflect",
):
    # stft: (Time, Channel, Freq) or (Time, Freq)
    x_stft = stft(
        x,
        n_fft=n_fft,
        n_shift=n_shift,
        win_length=win_length,
        window=window,
        pad_mode=pad_mode,
    )

    return stft2logmelspectrogram(
        x_stft, fs=fs, n_mels=n_mels, n_fft=n_fft, fmin=fmin, fmax=fmax, eps=eps
    )


class Spectrogram(object):
    def __init__(self, n_fft, n_shift, win_length=None, window="hann"):
        self.n_fft = n_fft
        self.n_shift = n_shift
        self.win_length = win_length
        self.window = window

    def __repr__(self):
        return (
            "{name}(n_fft={n_fft}, n_shift={n_shift}, "
            "win_length={win_length}, window={window})".format(
                name=self.__class__.__name__,
                n_fft=self.n_fft,
                n_shift=self.n_shift,
                win_length=self.win_length,
                window=self.window,
            )
        )

    def __call__(self, x):
        return spectrogram(
            x,
            n_fft=self.n_fft,
            n_shift=self.n_shift,
            win_length=self.win_length,
            window=self.window,
        )


class LogMelSpectrogram(object):
    def __init__(
        self,
        fs,
        n_mels,
        n_fft,
        n_shift,
        win_length=None,
        window="hann",
        fmin=None,
        fmax=None,
        eps=1e-10,
    ):
        self.fs = fs
        self.n_mels = n_mels
        self.n_fft = n_fft
        self.n_shift = n_shift
        self.win_length = win_length
        self.window = window
        self.fmin = fmin
        self.fmax = fmax
        self.eps = eps

    def __repr__(self):
        return (
            "{name}(fs={fs}, n_mels={n_mels}, n_fft={n_fft}, "
            "n_shift={n_shift}, win_length={win_length}, window={window}, "
            "fmin={fmin}, fmax={fmax}, eps={eps}))".format(
                name=self.__class__.__name__,
                fs=self.fs,
                n_mels=self.n_mels,
                n_fft=self.n_fft,
                n_shift=self.n_shift,
                win_length=self.win_length,
                window=self.window,
                fmin=self.fmin,
                fmax=self.fmax,
                eps=self.eps,
            )
        )

    def __call__(self, x):
        return logmelspectrogram(
            x,
            fs=self.fs,
            n_mels=self.n_mels,
            n_fft=self.n_fft,
            n_shift=self.n_shift,
            win_length=self.win_length,
            window=self.window,
        )


class Stft2LogMelSpectrogram(object):
    def __init__(self, fs, n_mels, n_fft, fmin=None, fmax=None, eps=1e-10):
        self.fs = fs
        self.n_mels = n_mels
        self.n_fft = n_fft
        self.fmin = fmin
        self.fmax = fmax
        self.eps = eps

    def __repr__(self):
        return (
            "{name}(fs={fs}, n_mels={n_mels}, n_fft={n_fft}, "
            "fmin={fmin}, fmax={fmax}, eps={eps}))".format(
                name=self.__class__.__name__,
                fs=self.fs,
                n_mels=self.n_mels,
                n_fft=self.n_fft,
                fmin=self.fmin,
                fmax=self.fmax,
                eps=self.eps,
            )
        )

    def __call__(self, x):
        return stft2logmelspectrogram(
            x,
            fs=self.fs,
            n_mels=self.n_mels,
            n_fft=self.n_fft,
            fmin=self.fmin,
            fmax=self.fmax,
        )


class Stft(object):
    def __init__(
        self,
        n_fft,
        n_shift,
        win_length=None,
        window="hann",
        center=True,
        pad_mode="reflect",
    ):
        self.n_fft = n_fft
        self.n_shift = n_shift
        self.win_length = win_length
        self.window = window
        self.center = center
        self.pad_mode = pad_mode

    def __repr__(self):
        return (
            "{name}(n_fft={n_fft}, n_shift={n_shift}, "
            "win_length={win_length}, window={window},"
            "center={center}, pad_mode={pad_mode})".format(
                name=self.__class__.__name__,
                n_fft=self.n_fft,
                n_shift=self.n_shift,
                win_length=self.win_length,
                window=self.window,
                center=self.center,
                pad_mode=self.pad_mode,
            )
        )

    def __call__(self, x):
        return stft(
            x,
            self.n_fft,
            self.n_shift,
            win_length=self.win_length,
            window=self.window,
            center=self.center,
            pad_mode=self.pad_mode,
        )


class IStft(object):
    def __init__(self, n_shift, win_length=None, window="hann", center=True):
        self.n_shift = n_shift
        self.win_length = win_length
        self.window = window
        self.center = center

    def __repr__(self):
        return (
            "{name}(n_shift={n_shift}, "
            "win_length={win_length}, window={window},"
            "center={center})".format(
                name=self.__class__.__name__,
                n_shift=self.n_shift,
                win_length=self.win_length,
                window=self.window,
                center=self.center,
            )
        )

    def __call__(self, x):
        return istft(
            x,
            self.n_shift,
            win_length=self.win_length,
            window=self.window,
            center=self.center,
        )