coqui-tts/utils/audio_lws.py

109 lines
4.2 KiB
Python

import os
import librosa
import pickle
import copy
import numpy as np
from scipy import signal
import lws
_mel_basis = None
class AudioProcessor(object):
def __init__(self, sample_rate, num_mels, min_level_db, frame_shift_ms,
frame_length_ms, ref_level_db, num_freq, power, preemphasis,
min_mel_freq, max_mel_freq, griffin_lim_iters=None, ):
self.sample_rate = sample_rate
self.num_mels = num_mels
self.min_level_db = min_level_db
self.frame_shift_ms = frame_shift_ms
self.frame_length_ms = frame_length_ms
self.ref_level_db = ref_level_db
self.num_freq = num_freq
self.power = power
self.min_mel_freq = min_mel_freq
self.max_mel_freq = max_mel_freq
self.griffin_lim_iters = griffin_lim_iters
self.preemphasis =preemphasis
_, self.hop_length, self.win_length = self._stft_parameters()
self.num_freq = (self.win_length // 2) + 1
if preemphasis == 0:
print(" | > Preemphasis is deactive.")
def save_wav(self, wav, path):
wav *= 32767 / max(0.01, np.max(np.abs(wav)))
librosa.output.write_wav(path, wav.astype(np.float), self.sample_rate, norm=True)
def _stft_parameters(self, ):
n_fft = (self.num_freq - 1) * 2
hop_length = int(self.frame_shift_ms / 1000.0 * self.sample_rate)
win_length = int(self.frame_length_ms / 1000.0 * self.sample_rate)
return n_fft, hop_length, win_length
def _lws_processor(self):
try:
return lws.lws(self.win_length, self.hop_length ,mode="speech")
except:
raise RuntimeError(" !! WindowLength({}) is not multiple of HopLength({}).".format(self.win_length, self.hop_length))
def _amp_to_db(self, x):
min_level = np.exp(self.min_level_db / 20 * np.log(10))
return 20 * np.log10(np.maximum(min_level, x))
def _db_to_amp(self, x):
return np.power(10.0, x * 0.05)
def _normalize(self, S):
return np.clip((S - self.min_level_db) / -self.min_level_db, 0, 1)
def _denormalize(self, S):
return (np.clip(S, 0, 1) * -self.min_level_db) + self.min_level_db
def apply_preemphasis(self, x):
if self.preemphasis == 0:
raise RuntimeError(" !! Preemphasis is applied with factor 0.0. ")
return signal.lfilter([1, -self.preemphasis], [1], x)
def apply_inv_preemphasis(self, x):
if self.preemphasis == 0:
raise RuntimeError(" !! Preemphasis is applied with factor 0.0. ")
return signal.lfilter([1], [1, -self.preemphasis], x)
def spectrogram(self, y):
if self.preemphasis:
D = self._lws_processor().stft(self.apply_preemphasis(y)).T
else:
D = self._lws_processor().stft(y).T
S = self._amp_to_db(np.abs(D)) - self.ref_level_db
return self._normalize(S)
def inv_spectrogram(self, spectrogram):
'''Converts spectrogram to waveform using librosa'''
S = self._denormalize(spectrogram)
S = self._db_to_amp(S + self.ref_level_db) # Convert back to linear
processor = self._lws_processor()
D = processor.run_lws(S.astype(np.float64).T ** self.power)
y = processor.istft(D).astype(np.float32)
# Reconstruct phase
if self.preemphasis:
return self.apply_inv_preemphasis(y)
return y
def _linear_to_mel(self, spectrogram):
global _mel_basis
if _mel_basis is None:
_mel_basis = self._build_mel_basis()
return np.dot(_mel_basis, spectrogram)
def _build_mel_basis(self, ):
return librosa.filters.mel(self.sample_rate, self.win_length, n_mels=self.num_mels)
# fmin=self.min_mel_freq, fmax=self.max_mel_freq)
def melspectrogram(self, y):
if self.preemphasis:
D = self._lws_processor().stft(self.apply_preemphasis(y)).T
else:
D = self._lws_processor().stft(y).T
S = self._amp_to_db(self._linear_to_mel(np.abs(D))) - self.ref_level_db
return self._normalize(S)