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A10G
Running
on
A10G
import torch | |
import torchaudio.functional as F | |
from torch import Tensor, nn | |
from torchaudio.transforms import MelScale | |
class LinearSpectrogram(nn.Module): | |
def __init__( | |
self, | |
n_fft=2048, | |
win_length=2048, | |
hop_length=512, | |
center=False, | |
mode="pow2_sqrt", | |
): | |
super().__init__() | |
self.n_fft = n_fft | |
self.win_length = win_length | |
self.hop_length = hop_length | |
self.center = center | |
self.mode = mode | |
self.register_buffer("window", torch.hann_window(win_length), persistent=False) | |
def forward(self, y: Tensor) -> Tensor: | |
if y.ndim == 3: | |
y = y.squeeze(1) | |
y = torch.nn.functional.pad( | |
y.unsqueeze(1), | |
( | |
(self.win_length - self.hop_length) // 2, | |
(self.win_length - self.hop_length + 1) // 2, | |
), | |
mode="reflect", | |
).squeeze(1) | |
spec = torch.stft( | |
y, | |
self.n_fft, | |
hop_length=self.hop_length, | |
win_length=self.win_length, | |
window=self.window, | |
center=self.center, | |
pad_mode="reflect", | |
normalized=False, | |
onesided=True, | |
return_complex=True, | |
) | |
spec = torch.view_as_real(spec) | |
if self.mode == "pow2_sqrt": | |
spec = torch.sqrt(spec.pow(2).sum(-1) + 1e-6) | |
return spec | |
class LogMelSpectrogram(nn.Module): | |
def __init__( | |
self, | |
sample_rate=44100, | |
n_fft=2048, | |
win_length=2048, | |
hop_length=512, | |
n_mels=128, | |
center=False, | |
f_min=0.0, | |
f_max=None, | |
): | |
super().__init__() | |
self.sample_rate = sample_rate | |
self.n_fft = n_fft | |
self.win_length = win_length | |
self.hop_length = hop_length | |
self.center = center | |
self.n_mels = n_mels | |
self.f_min = f_min | |
self.f_max = f_max or float(sample_rate // 2) | |
self.spectrogram = LinearSpectrogram(n_fft, win_length, hop_length, center) | |
fb = F.melscale_fbanks( | |
n_freqs=self.n_fft // 2 + 1, | |
f_min=self.f_min, | |
f_max=self.f_max, | |
n_mels=self.n_mels, | |
sample_rate=self.sample_rate, | |
norm="slaney", | |
mel_scale="slaney", | |
) | |
self.register_buffer( | |
"fb", | |
fb, | |
persistent=False, | |
) | |
def compress(self, x: Tensor) -> Tensor: | |
return torch.log(torch.clamp(x, min=1e-5)) | |
def decompress(self, x: Tensor) -> Tensor: | |
return torch.exp(x) | |
def apply_mel_scale(self, x: Tensor) -> Tensor: | |
return torch.matmul(x.transpose(-1, -2), self.fb).transpose(-1, -2) | |
def forward( | |
self, x: Tensor, return_linear: bool = False, sample_rate: int = None | |
) -> Tensor: | |
if sample_rate is not None and sample_rate != self.sample_rate: | |
x = F.resample(x, orig_freq=sample_rate, new_freq=self.sample_rate) | |
linear = self.spectrogram(x) | |
x = self.apply_mel_scale(linear) | |
x = self.compress(x) | |
if return_linear: | |
return x, self.compress(linear) | |
return x | |