|  |  | 
					
						
						|  | from typing import Literal | 
					
						
						|  |  | 
					
						
						|  | import torch | 
					
						
						|  | import torch.nn as nn | 
					
						
						|  | from librosa.filters import mel as librosa_mel_fn | 
					
						
						|  |  | 
					
						
						|  |  | 
					
						
						|  | def dynamic_range_compression_torch(x, C=1, clip_val=1e-5, *, norm_fn): | 
					
						
						|  | return norm_fn(torch.clamp(x, min=clip_val) * C) | 
					
						
						|  |  | 
					
						
						|  |  | 
					
						
						|  | def spectral_normalize_torch(magnitudes, norm_fn): | 
					
						
						|  | output = dynamic_range_compression_torch(magnitudes, norm_fn=norm_fn) | 
					
						
						|  | return output | 
					
						
						|  |  | 
					
						
						|  |  | 
					
						
						|  | class MelConverter(nn.Module): | 
					
						
						|  |  | 
					
						
						|  | def __init__( | 
					
						
						|  | self, | 
					
						
						|  | *, | 
					
						
						|  | sampling_rate: float, | 
					
						
						|  | n_fft: int, | 
					
						
						|  | num_mels: int, | 
					
						
						|  | hop_size: int, | 
					
						
						|  | win_size: int, | 
					
						
						|  | fmin: float, | 
					
						
						|  | fmax: float, | 
					
						
						|  | norm_fn, | 
					
						
						|  | ): | 
					
						
						|  | super().__init__() | 
					
						
						|  | self.sampling_rate = sampling_rate | 
					
						
						|  | self.n_fft = n_fft | 
					
						
						|  | self.num_mels = num_mels | 
					
						
						|  | self.hop_size = hop_size | 
					
						
						|  | self.win_size = win_size | 
					
						
						|  | self.fmin = fmin | 
					
						
						|  | self.fmax = fmax | 
					
						
						|  | self.norm_fn = norm_fn | 
					
						
						|  |  | 
					
						
						|  | mel = librosa_mel_fn(sr=self.sampling_rate, | 
					
						
						|  | n_fft=self.n_fft, | 
					
						
						|  | n_mels=self.num_mels, | 
					
						
						|  | fmin=self.fmin, | 
					
						
						|  | fmax=self.fmax) | 
					
						
						|  | mel_basis = torch.from_numpy(mel).float() | 
					
						
						|  | hann_window = torch.hann_window(self.win_size) | 
					
						
						|  |  | 
					
						
						|  | self.register_buffer('mel_basis', mel_basis) | 
					
						
						|  | self.register_buffer('hann_window', hann_window) | 
					
						
						|  |  | 
					
						
						|  | @property | 
					
						
						|  | def device(self): | 
					
						
						|  | return self.mel_basis.device | 
					
						
						|  |  | 
					
						
						|  | def forward(self, waveform: torch.Tensor, center: bool = False) -> torch.Tensor: | 
					
						
						|  | waveform = waveform.clamp(min=-1., max=1.).to(self.device) | 
					
						
						|  |  | 
					
						
						|  | waveform = torch.nn.functional.pad( | 
					
						
						|  | waveform.unsqueeze(1), | 
					
						
						|  | [int((self.n_fft - self.hop_size) / 2), | 
					
						
						|  | int((self.n_fft - self.hop_size) / 2)], | 
					
						
						|  | mode='reflect') | 
					
						
						|  | waveform = waveform.squeeze(1) | 
					
						
						|  |  | 
					
						
						|  | spec = torch.stft(waveform, | 
					
						
						|  | self.n_fft, | 
					
						
						|  | hop_length=self.hop_size, | 
					
						
						|  | win_length=self.win_size, | 
					
						
						|  | window=self.hann_window, | 
					
						
						|  | center=center, | 
					
						
						|  | pad_mode='reflect', | 
					
						
						|  | normalized=False, | 
					
						
						|  | onesided=True, | 
					
						
						|  | return_complex=True) | 
					
						
						|  |  | 
					
						
						|  | spec = torch.view_as_real(spec) | 
					
						
						|  | spec = torch.sqrt(spec.pow(2).sum(-1) + (1e-9)) | 
					
						
						|  | spec = torch.matmul(self.mel_basis, spec) | 
					
						
						|  | spec = spectral_normalize_torch(spec, self.norm_fn) | 
					
						
						|  |  | 
					
						
						|  | return spec | 
					
						
						|  |  | 
					
						
						|  |  | 
					
						
						|  | def get_mel_converter(mode: Literal['16k', '44k']) -> MelConverter: | 
					
						
						|  | if mode == '16k': | 
					
						
						|  | return MelConverter(sampling_rate=16_000, | 
					
						
						|  | n_fft=1024, | 
					
						
						|  | num_mels=80, | 
					
						
						|  | hop_size=256, | 
					
						
						|  | win_size=1024, | 
					
						
						|  | fmin=0, | 
					
						
						|  | fmax=8_000, | 
					
						
						|  | norm_fn=torch.log10) | 
					
						
						|  | elif mode == '44k': | 
					
						
						|  | return MelConverter(sampling_rate=44_100, | 
					
						
						|  | n_fft=2048, | 
					
						
						|  | num_mels=128, | 
					
						
						|  | hop_size=512, | 
					
						
						|  | win_size=2048, | 
					
						
						|  | fmin=0, | 
					
						
						|  | fmax=44100 / 2, | 
					
						
						|  | norm_fn=torch.log) | 
					
						
						|  | else: | 
					
						
						|  | raise ValueError(f'Unknown mode: {mode}') | 
					
						
						|  |  |