chong.zhang
update
96fe5d9
from typing import Tuple, List
import torch
from torch import nn
from torch.nn import Conv2d
from torch.nn.utils import weight_norm
class MultiPeriodDiscriminator(nn.Module):
"""
Multi-Period Discriminator module adapted from https://github.com/jik876/hifi-gan.
Additionally, it allows incorporating conditional information with a learned embeddings table.
Args:
periods (tuple[int]): Tuple of periods for each discriminator.
num_embeddings (int, optional): Number of embeddings. None means non-conditional discriminator.
Defaults to None.
"""
def __init__(self, periods: Tuple[int] = (2, 3, 5, 7, 11), num_embeddings: int = None):
super().__init__()
self.discriminators = nn.ModuleList([DiscriminatorP(period=p, num_embeddings=num_embeddings) for p in periods])
def forward(
self, y: torch.Tensor, y_hat: torch.Tensor, bandwidth_id: torch.Tensor = None
) -> Tuple[List[torch.Tensor], List[torch.Tensor], List[List[torch.Tensor]], List[List[torch.Tensor]]]:
y_d_rs = []
y_d_gs = []
fmap_rs = []
fmap_gs = []
for d in self.discriminators:
y_d_r, fmap_r = d(x=y, cond_embedding_id=bandwidth_id)
y_d_g, fmap_g = d(x=y_hat, cond_embedding_id=bandwidth_id)
y_d_rs.append(y_d_r)
fmap_rs.append(fmap_r)
y_d_gs.append(y_d_g)
fmap_gs.append(fmap_g)
return y_d_rs, y_d_gs, fmap_rs, fmap_gs
class DiscriminatorP(nn.Module):
def __init__(
self,
period: int,
in_channels: int = 1,
kernel_size: int = 5,
stride: int = 3,
lrelu_slope: float = 0.1,
num_embeddings: int = None,
):
super().__init__()
self.period = period
self.convs = nn.ModuleList(
[
weight_norm(Conv2d(in_channels, 32, (kernel_size, 1), (stride, 1), padding=(kernel_size // 2, 0))),
weight_norm(Conv2d(32, 128, (kernel_size, 1), (stride, 1), padding=(kernel_size // 2, 0))),
weight_norm(Conv2d(128, 512, (kernel_size, 1), (stride, 1), padding=(kernel_size // 2, 0))),
weight_norm(Conv2d(512, 1024, (kernel_size, 1), (stride, 1), padding=(kernel_size // 2, 0))),
weight_norm(Conv2d(1024, 1024, (kernel_size, 1), (1, 1), padding=(kernel_size // 2, 0))),
]
)
if num_embeddings is not None:
self.emb = torch.nn.Embedding(num_embeddings=num_embeddings, embedding_dim=1024)
torch.nn.init.zeros_(self.emb.weight)
self.conv_post = weight_norm(Conv2d(1024, 1, (3, 1), 1, padding=(1, 0)))
self.lrelu_slope = lrelu_slope
def forward(
self, x: torch.Tensor, cond_embedding_id: torch.Tensor = None
) -> Tuple[torch.Tensor, List[torch.Tensor]]:
x = x.unsqueeze(1)
fmap = []
# 1d to 2d
b, c, t = x.shape
if t % self.period != 0: # pad first
n_pad = self.period - (t % self.period)
x = torch.nn.functional.pad(x, (0, n_pad), "reflect")
t = t + n_pad
x = x.view(b, c, t // self.period, self.period)
for i, l in enumerate(self.convs):
x = l(x)
x = torch.nn.functional.leaky_relu(x, self.lrelu_slope)
if i > 0:
fmap.append(x)
if cond_embedding_id is not None:
emb = self.emb(cond_embedding_id)
h = (emb.view(1, -1, 1, 1) * x).sum(dim=1, keepdims=True)
else:
h = 0
x = self.conv_post(x)
fmap.append(x)
x += h
x = torch.flatten(x, 1, -1)
return x, fmap
class MultiResolutionDiscriminator(nn.Module):
def __init__(
self,
resolutions: Tuple[Tuple[int, int, int]] = ((1024, 256, 1024), (2048, 512, 2048), (512, 128, 512)),
num_embeddings: int = None,
):
"""
Multi-Resolution Discriminator module adapted from https://github.com/mindslab-ai/univnet.
Additionally, it allows incorporating conditional information with a learned embeddings table.
Args:
resolutions (tuple[tuple[int, int, int]]): Tuple of resolutions for each discriminator.
Each resolution should be a tuple of (n_fft, hop_length, win_length).
num_embeddings (int, optional): Number of embeddings. None means non-conditional discriminator.
Defaults to None.
"""
super().__init__()
self.discriminators = nn.ModuleList(
[DiscriminatorR(resolution=r, num_embeddings=num_embeddings) for r in resolutions]
)
def forward(
self, y: torch.Tensor, y_hat: torch.Tensor, bandwidth_id: torch.Tensor = None
) -> Tuple[List[torch.Tensor], List[torch.Tensor], List[List[torch.Tensor]], List[List[torch.Tensor]]]:
y_d_rs = []
y_d_gs = []
fmap_rs = []
fmap_gs = []
for d in self.discriminators:
y_d_r, fmap_r = d(x=y, cond_embedding_id=bandwidth_id)
y_d_g, fmap_g = d(x=y_hat, cond_embedding_id=bandwidth_id)
y_d_rs.append(y_d_r)
fmap_rs.append(fmap_r)
y_d_gs.append(y_d_g)
fmap_gs.append(fmap_g)
return y_d_rs, y_d_gs, fmap_rs, fmap_gs
class DiscriminatorR(nn.Module):
def __init__(
self,
resolution: Tuple[int, int, int],
channels: int = 64,
in_channels: int = 1,
num_embeddings: int = None,
lrelu_slope: float = 0.1,
):
super().__init__()
self.resolution = resolution
self.in_channels = in_channels
self.lrelu_slope = lrelu_slope
self.convs = nn.ModuleList(
[
weight_norm(nn.Conv2d(in_channels, channels, kernel_size=(7, 5), stride=(2, 2), padding=(3, 2))),
weight_norm(nn.Conv2d(channels, channels, kernel_size=(5, 3), stride=(2, 1), padding=(2, 1))),
weight_norm(nn.Conv2d(channels, channels, kernel_size=(5, 3), stride=(2, 2), padding=(2, 1))),
weight_norm(nn.Conv2d(channels, channels, kernel_size=3, stride=(2, 1), padding=1)),
weight_norm(nn.Conv2d(channels, channels, kernel_size=3, stride=(2, 2), padding=1)),
]
)
if num_embeddings is not None:
self.emb = torch.nn.Embedding(num_embeddings=num_embeddings, embedding_dim=channels)
torch.nn.init.zeros_(self.emb.weight)
self.conv_post = weight_norm(nn.Conv2d(channels, 1, (3, 3), padding=(1, 1)))
def forward(
self, x: torch.Tensor, cond_embedding_id: torch.Tensor = None
) -> Tuple[torch.Tensor, List[torch.Tensor]]:
fmap = []
x = self.spectrogram(x)
x = x.unsqueeze(1)
for l in self.convs:
x = l(x)
x = torch.nn.functional.leaky_relu(x, self.lrelu_slope)
fmap.append(x)
if cond_embedding_id is not None:
emb = self.emb(cond_embedding_id)
h = (emb.view(1, -1, 1, 1) * x).sum(dim=1, keepdims=True)
else:
h = 0
x = self.conv_post(x)
fmap.append(x)
x += h
x = torch.flatten(x, 1, -1)
return x, fmap
def spectrogram(self, x: torch.Tensor) -> torch.Tensor:
n_fft, hop_length, win_length = self.resolution
magnitude_spectrogram = torch.stft(
x,
n_fft=n_fft,
hop_length=hop_length,
win_length=win_length,
window=None, # interestingly rectangular window kind of works here
center=True,
return_complex=True,
).abs()
return magnitude_spectrogram