File size: 20,390 Bytes
d5ee97c
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
# -*- coding: utf-8 -*-
# Copyright 2020 Minh Nguyen (@dathudeptrai)
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Perform preprocessing, with raw feature extraction and normalization of train/valid split."""

import argparse
import glob
import logging
import os
import yaml

import librosa
import numpy as np
import pyworld as pw

from functools import partial
from multiprocessing import Pool
from sklearn.model_selection import train_test_split
from sklearn.preprocessing import StandardScaler
from tqdm import tqdm

from tensorflow_tts.processor import LJSpeechProcessor
from tensorflow_tts.processor import BakerProcessor
from tensorflow_tts.processor import KSSProcessor
from tensorflow_tts.processor import LibriTTSProcessor
from tensorflow_tts.processor import ThorstenProcessor
from tensorflow_tts.processor import LJSpeechUltimateProcessor
from tensorflow_tts.processor import SynpaflexProcessor
from tensorflow_tts.processor import JSUTProcessor
from tensorflow_tts.processor.ljspeech import LJSPEECH_SYMBOLS
from tensorflow_tts.processor.baker import BAKER_SYMBOLS
from tensorflow_tts.processor.kss import KSS_SYMBOLS
from tensorflow_tts.processor.libritts import LIBRITTS_SYMBOLS
from tensorflow_tts.processor.thorsten import THORSTEN_SYMBOLS
from tensorflow_tts.processor.ljspeechu import LJSPEECH_U_SYMBOLS
from tensorflow_tts.processor.synpaflex import SYNPAFLEX_SYMBOLS
from tensorflow_tts.processor.jsut import JSUT_SYMBOLS

from tensorflow_tts.utils import remove_outlier

os.environ["CUDA_VISIBLE_DEVICES"] = ""


def parse_and_config():
    """Parse arguments and set configuration parameters."""
    parser = argparse.ArgumentParser(
        description="Preprocess audio and text features "
        "(See detail in tensorflow_tts/bin/preprocess_dataset.py)."
    )
    parser.add_argument(
        "--rootdir",
        default=None,
        type=str,
        required=True,
        help="Directory containing the dataset files.",
    )
    parser.add_argument(
        "--outdir",
        default=None,
        type=str,
        required=True,
        help="Output directory where features will be saved.",
    )
    parser.add_argument(
        "--dataset",
        type=str,
        default="ljspeech",
        choices=["ljspeech", "kss", "libritts", "baker", "thorsten", "ljspeechu", "synpaflex", "jsut"],
        help="Dataset to preprocess.",
    )
    parser.add_argument(
        "--config", type=str, required=True, help="YAML format configuration file."
    )
    parser.add_argument(
        "--n_cpus",
        type=int,
        default=4,
        required=False,
        help="Number of CPUs to use in parallel.",
    )
    parser.add_argument(
        "--test_size",
        type=float,
        default=0.05,
        required=False,
        help="Proportion of files to use as test dataset.",
    )
    parser.add_argument(
        "--verbose",
        type=int,
        default=0,
        choices=[0, 1, 2],
        help="Logging level. 0: DEBUG, 1: INFO and WARNING, 2: INFO, WARNING, and ERROR",
    )
    args = parser.parse_args()

    # set logger
    FORMAT = "%(asctime)s (%(module)s:%(lineno)d) %(levelname)s: %(message)s"
    log_level = {0: logging.DEBUG, 1: logging.WARNING, 2: logging.ERROR}
    logging.basicConfig(level=log_level[args.verbose], format=FORMAT)

    # load config
    config = yaml.load(open(args.config), Loader=yaml.SafeLoader)
    config.update(vars(args))
    # config checks
    assert config["format"] == "npy", "'npy' is the only supported format."
    return config


def ph_based_trim(
    config,
    utt_id: str,
    text_ids: np.array,
    raw_text: str,
    audio: np.array,
    hop_size: int,
) -> (bool, np.array, np.array):
    """
    Args:
        config: Parsed yaml config
        utt_id: file name
        text_ids: array with text ids
        raw_text: raw text of file
        audio: parsed wav file
        hop_size: Hop size
    Returns: (bool, np.array, np.array) => if trimmed return True, new text_ids, new audio_array
    """

    os.makedirs(os.path.join(config["rootdir"], "trimmed-durations"), exist_ok=True)
    duration_path = config.get(
        "duration_path", os.path.join(config["rootdir"], "durations")
    )
    duration_fixed_path = config.get(
        "duration_fixed_path", os.path.join(config["rootdir"], "trimmed-durations")
    )
    sil_ph = ["SIL", "END"]  # TODO FIX hardcoded values
    text = raw_text.split(" ")

    trim_start, trim_end = False, False

    if text[0] in sil_ph:
        trim_start = True

    if text[-1] in sil_ph:
        trim_end = True

    if not trim_start and not trim_end:
        return False, text_ids, audio

    idx_start, idx_end = (
        0 if not trim_start else 1,
        text_ids.__len__() if not trim_end else -1,
    )
    text_ids = text_ids[idx_start:idx_end]
    durations = np.load(os.path.join(duration_path, f"{utt_id}-durations.npy"))
    if trim_start:
        s_trim = int(durations[0] * hop_size)
        audio = audio[s_trim:]
    if trim_end:
        e_trim = int(durations[-1] * hop_size)
        audio = audio[:-e_trim]

    durations = durations[idx_start:idx_end]
    np.save(os.path.join(duration_fixed_path, f"{utt_id}-durations.npy"), durations)
    return True, text_ids, audio


def gen_audio_features(item, config):
    """Generate audio features and transformations
    Args:
        item (Dict): dictionary containing the attributes to encode.
        config (Dict): configuration dictionary.
    Returns:
        (bool): keep this sample or not.
        mel (ndarray): mel matrix in np.float32.
        energy (ndarray): energy audio profile.
        f0 (ndarray): fundamental frequency.
        item (Dict): dictionary containing the updated attributes.
    """
    # get info from sample.
    audio = item["audio"]
    utt_id = item["utt_id"]
    rate = item["rate"]

    # check audio properties
    assert len(audio.shape) == 1, f"{utt_id} seems to be multi-channel signal."
    assert np.abs(audio).max() <= 1.0, f"{utt_id} is different from 16 bit PCM."
    
    # check sample rate
    if rate != config["sampling_rate"]:
        audio = librosa.resample(audio, rate, config["sampling_rate"])
        logging.info(f"{utt_id} sampling rate is {rate}, not {config['sampling_rate']}, we resample it.")

    # trim silence
    if config["trim_silence"]:
        if "trim_mfa" in config and config["trim_mfa"]:
            _, item["text_ids"], audio = ph_based_trim(
                config,
                utt_id,
                item["text_ids"],
                item["raw_text"],
                audio,
                config["hop_size"],
            )
            if (
                audio.__len__() < 1
            ):  # very short files can get trimmed fully if mfa didnt extract any tokens LibriTTS maybe take only longer files?
                logging.warning(
                    f"File have only silence or MFA didnt extract any token {utt_id}"
                )
                return False, None, None, None, item
        else:
            audio, _ = librosa.effects.trim(
                audio,
                top_db=config["trim_threshold_in_db"],
                frame_length=config["trim_frame_size"],
                hop_length=config["trim_hop_size"],
            )

    # resample audio if necessary
    if "sampling_rate_for_feats" in config:
        audio = librosa.resample(audio, rate, config["sampling_rate_for_feats"])
        sampling_rate = config["sampling_rate_for_feats"]
        assert (
            config["hop_size"] * config["sampling_rate_for_feats"] % rate == 0
        ), "'hop_size' must be 'int' value. Please check if 'sampling_rate_for_feats' is correct."
        hop_size = config["hop_size"] * config["sampling_rate_for_feats"] // rate
    else:
        sampling_rate = config["sampling_rate"]
        hop_size = config["hop_size"]

    # get spectrogram
    D = librosa.stft(
        audio,
        n_fft=config["fft_size"],
        hop_length=hop_size,
        win_length=config["win_length"],
        window=config["window"],
        pad_mode="reflect",
    )
    S, _ = librosa.magphase(D)  # (#bins, #frames)

    # get mel basis
    fmin = 0 if config["fmin"] is None else config["fmin"]
    fmax = sampling_rate // 2 if config["fmax"] is None else config["fmax"]
    mel_basis = librosa.filters.mel(
        sr=sampling_rate,
        n_fft=config["fft_size"],
        n_mels=config["num_mels"],
        fmin=fmin,
        fmax=fmax,
    )
    mel = np.log10(np.maximum(np.dot(mel_basis, S), 1e-10)).T  # (#frames, #bins)

    # check audio and feature length
    audio = np.pad(audio, (0, config["fft_size"]), mode="edge")
    audio = audio[: len(mel) * hop_size]
    assert len(mel) * hop_size == len(audio)

    # extract raw pitch
    _f0, t = pw.dio(
        audio.astype(np.double),
        fs=sampling_rate,
        f0_ceil=fmax,
        frame_period=1000 * hop_size / sampling_rate,
    )
    f0 = pw.stonemask(audio.astype(np.double), _f0, t, sampling_rate)
    if len(f0) >= len(mel):
        f0 = f0[: len(mel)]
    else:
        f0 = np.pad(f0, (0, len(mel) - len(f0)))

    # extract energy
    energy = np.sqrt(np.sum(S ** 2, axis=0))
    assert len(mel) == len(f0) == len(energy)

    # remove outlier f0/energy
    f0 = remove_outlier(f0)
    energy = remove_outlier(energy)

    # apply global gain
    if config["global_gain_scale"] > 0.0:
        audio *= config["global_gain_scale"]
    if np.abs(audio).max() >= 1.0:
        logging.warn(
            f"{utt_id} causes clipping. It is better to reconsider global gain scale value."
        )
    item["audio"] = audio
    item["mel"] = mel
    item["f0"] = f0
    item["energy"] = energy
    return True, mel, energy, f0, item


def save_statistics_to_file(scaler_list, config):
    """Save computed statistics to disk.
    Args:
        scaler_list (List): List of scalers containing statistics to save.
        config (Dict): configuration dictionary.
    """
    for scaler, name in scaler_list:
        stats = np.stack((scaler.mean_, scaler.scale_))
        np.save(
            os.path.join(config["outdir"], f"stats{name}.npy"),
            stats.astype(np.float32),
            allow_pickle=False,
        )


def save_features_to_file(features, subdir, config):
    """Save transformed dataset features in disk.
    Args:
        features (Dict): dictionary containing the attributes to save.
        subdir (str): data split folder where features will be saved.
        config (Dict): configuration dictionary.
    """
    utt_id = features["utt_id"]

    if config["format"] == "npy":
        save_list = [
            (features["audio"], "wavs", "wave", np.float32),
            (features["mel"], "raw-feats", "raw-feats", np.float32),
            (features["text_ids"], "ids", "ids", np.int32),
            (features["f0"], "raw-f0", "raw-f0", np.float32),
            (features["energy"], "raw-energies", "raw-energy", np.float32),
        ]
        for item, name_dir, name_file, fmt in save_list:
            np.save(
                os.path.join(
                    config["outdir"], subdir, name_dir, f"{utt_id}-{name_file}.npy"
                ),
                item.astype(fmt),
                allow_pickle=False,
            )
    else:
        raise ValueError("'npy' is the only supported format.")


def preprocess():
    """Run preprocessing process and compute statistics for normalizing."""
    config = parse_and_config()

    dataset_processor = {
        "ljspeech": LJSpeechProcessor,
        "kss": KSSProcessor,
        "libritts": LibriTTSProcessor,
        "baker": BakerProcessor,
        "thorsten": ThorstenProcessor,
        "ljspeechu": LJSpeechUltimateProcessor,
        "synpaflex": SynpaflexProcessor,
        "jsut": JSUTProcessor,
    }

    dataset_symbol = {
        "ljspeech": LJSPEECH_SYMBOLS,
        "kss": KSS_SYMBOLS,
        "libritts": LIBRITTS_SYMBOLS,
        "baker": BAKER_SYMBOLS,
        "thorsten": THORSTEN_SYMBOLS,
        "ljspeechu": LJSPEECH_U_SYMBOLS,
        "synpaflex": SYNPAFLEX_SYMBOLS,
        "jsut": JSUT_SYMBOLS,
    }

    dataset_cleaner = {
        "ljspeech": "english_cleaners",
        "kss": "korean_cleaners",
        "libritts": None,
        "baker": None,
        "thorsten": "german_cleaners",
        "ljspeechu": "english_cleaners",
        "synpaflex": "basic_cleaners",
        "jsut": None,
    }

    logging.info(f"Selected '{config['dataset']}' processor.")
    processor = dataset_processor[config["dataset"]](
        config["rootdir"],
        symbols=dataset_symbol[config["dataset"]],
        cleaner_names=dataset_cleaner[config["dataset"]],
    )

    # check output directories
    build_dir = lambda x: [
        os.makedirs(os.path.join(config["outdir"], x, y), exist_ok=True)
        for y in ["raw-feats", "wavs", "ids", "raw-f0", "raw-energies"]
    ]
    build_dir("train")
    build_dir("valid")

    # save pretrained-processor to feature dir
    processor._save_mapper(
        os.path.join(config["outdir"], f"{config['dataset']}_mapper.json"),
        extra_attrs_to_save={"pinyin_dict": processor.pinyin_dict}
        if config["dataset"] == "baker"
        else {},
    )

    # build train test split
    if config["dataset"] == "libritts":
        train_split, valid_split, _, _ = train_test_split(
            processor.items,
            [i[-1] for i in processor.items],
            test_size=config["test_size"],
            random_state=42,
            shuffle=True,
        )
    else:
        train_split, valid_split = train_test_split(
            processor.items,
            test_size=config["test_size"],
            random_state=42,
            shuffle=True,
        )
    logging.info(f"Training items: {len(train_split)}")
    logging.info(f"Validation items: {len(valid_split)}")

    get_utt_id = lambda x: os.path.split(x[1])[-1].split(".")[0]
    train_utt_ids = [get_utt_id(x) for x in train_split]
    valid_utt_ids = [get_utt_id(x) for x in valid_split]

    # save train and valid utt_ids to track later
    np.save(os.path.join(config["outdir"], "train_utt_ids.npy"), train_utt_ids)
    np.save(os.path.join(config["outdir"], "valid_utt_ids.npy"), valid_utt_ids)

    # define map iterator
    def iterator_data(items_list):
        for item in items_list:
            yield processor.get_one_sample(item)

    train_iterator_data = iterator_data(train_split)
    valid_iterator_data = iterator_data(valid_split)

    p = Pool(config["n_cpus"])

    # preprocess train files and get statistics for normalizing
    partial_fn = partial(gen_audio_features, config=config)
    train_map = p.imap_unordered(
        partial_fn,
        tqdm(train_iterator_data, total=len(train_split), desc="[Preprocessing train]"),
        chunksize=10,
    )
    # init scaler for multiple features
    scaler_mel = StandardScaler(copy=False)
    scaler_energy = StandardScaler(copy=False)
    scaler_f0 = StandardScaler(copy=False)

    id_to_remove = []
    for result, mel, energy, f0, features in train_map:
        if not result:
            id_to_remove.append(features["utt_id"])
            continue
        save_features_to_file(features, "train", config)
        # partial fitting of scalers
        if len(energy[energy != 0]) == 0 or len(f0[f0 != 0]) == 0:
            id_to_remove.append(features["utt_id"])
            continue
        # partial fitting of scalers
        if len(energy[energy != 0]) == 0 or len(f0[f0 != 0]) == 0:
            id_to_remove.append(features["utt_id"])
            continue
        scaler_mel.partial_fit(mel)
        scaler_energy.partial_fit(energy[energy != 0].reshape(-1, 1))
        scaler_f0.partial_fit(f0[f0 != 0].reshape(-1, 1))

    if len(id_to_remove) > 0:
        np.save(
            os.path.join(config["outdir"], "train_utt_ids.npy"),
            [i for i in train_utt_ids if i not in id_to_remove],
        )
        logging.info(
            f"removed {len(id_to_remove)} cause of too many outliers or bad mfa extraction"
        )

    # save statistics to file
    logging.info("Saving computed statistics.")
    scaler_list = [(scaler_mel, ""), (scaler_energy, "_energy"), (scaler_f0, "_f0")]
    save_statistics_to_file(scaler_list, config)

    # preprocess valid files
    partial_fn = partial(gen_audio_features, config=config)
    valid_map = p.imap_unordered(
        partial_fn,
        tqdm(valid_iterator_data, total=len(valid_split), desc="[Preprocessing valid]"),
        chunksize=10,
    )
    for *_, features in valid_map:
        save_features_to_file(features, "valid", config)


def gen_normal_mel(mel_path, scaler, config):
    """Normalize the mel spectrogram and save it to the corresponding path.
    Args:
        mel_path (string): path of the mel spectrogram to normalize.
        scaler (sklearn.base.BaseEstimator): scaling function to use for normalize.
        config (Dict): configuration dictionary.
    """
    mel = np.load(mel_path)
    mel_norm = scaler.transform(mel)
    path, file_name = os.path.split(mel_path)
    *_, subdir, suffix = path.split(os.sep)

    utt_id = file_name.split(f"-{suffix}.npy")[0]
    np.save(
        os.path.join(
            config["outdir"], subdir, "norm-feats", f"{utt_id}-norm-feats.npy"
        ),
        mel_norm.astype(np.float32),
        allow_pickle=False,
    )


def normalize():
    """Normalize mel spectrogram with pre-computed statistics."""
    config = parse_and_config()
    if config["format"] == "npy":
        # init scaler with saved values
        scaler = StandardScaler()
        scaler.mean_, scaler.scale_ = np.load(
            os.path.join(config["outdir"], "stats.npy")
        )
        scaler.n_features_in_ = config["num_mels"]
    else:
        raise ValueError("'npy' is the only supported format.")

    # find all "raw-feats" files in both train and valid folders
    glob_path = os.path.join(config["rootdir"], "**", "raw-feats", "*.npy")
    mel_raw_feats = glob.glob(glob_path, recursive=True)
    logging.info(f"Files to normalize: {len(mel_raw_feats)}")

    # check for output directories
    os.makedirs(os.path.join(config["outdir"], "train", "norm-feats"), exist_ok=True)
    os.makedirs(os.path.join(config["outdir"], "valid", "norm-feats"), exist_ok=True)

    p = Pool(config["n_cpus"])
    partial_fn = partial(gen_normal_mel, scaler=scaler, config=config)
    list(p.map(partial_fn, tqdm(mel_raw_feats, desc="[Normalizing]")))


def compute_statistics():
    """Compute mean / std statistics of some features for later normalization."""
    config = parse_and_config()

    # find features files for the train split
    glob_fn = lambda x: glob.glob(os.path.join(config["rootdir"], "train", x, "*.npy"))
    glob_mel = glob_fn("raw-feats")
    glob_f0 = glob_fn("raw-f0")
    glob_energy = glob_fn("raw-energies")
    assert (
        len(glob_mel) == len(glob_f0) == len(glob_energy)
    ), "Features, f0 and energies have different files in training split."

    logging.info(f"Computing statistics for {len(glob_mel)} files.")
    # init scaler for multiple features
    scaler_mel = StandardScaler(copy=False)
    scaler_energy = StandardScaler(copy=False)
    scaler_f0 = StandardScaler(copy=False)

    for mel, f0, energy in tqdm(
        zip(glob_mel, glob_f0, glob_energy), total=len(glob_mel)
    ):
        # remove outliers
        energy = np.load(energy)
        f0 = np.load(f0)
        # partial fitting of scalers
        scaler_mel.partial_fit(np.load(mel))
        scaler_energy.partial_fit(energy[energy != 0].reshape(-1, 1))
        scaler_f0.partial_fit(f0[f0 != 0].reshape(-1, 1))

    # save statistics to file
    logging.info("Saving computed statistics.")
    scaler_list = [(scaler_mel, ""), (scaler_energy, "_energy"), (scaler_f0, "_f0")]
    save_statistics_to_file(scaler_list, config)


if __name__ == "__main__":
    preprocess()