FrankZxShen's picture
init
ce252ec
import math
from math import sqrt
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch.nn import Mish
class Conv1d(torch.nn.Conv1d):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
nn.init.kaiming_normal_(self.weight)
class SinusoidalPosEmb(nn.Module):
def __init__(self, dim):
super().__init__()
self.dim = dim
def forward(self, x):
device = x.device
half_dim = self.dim // 2
emb = math.log(10000) / (half_dim - 1)
emb = torch.exp(torch.arange(half_dim, device=device) * -emb)
emb = x[:, None] * emb[None, :]
emb = torch.cat((emb.sin(), emb.cos()), dim=-1)
return emb
class ResidualBlock(nn.Module):
def __init__(self, encoder_hidden, residual_channels, dilation):
super().__init__()
self.residual_channels = residual_channels
self.dilated_conv = nn.Conv1d(
residual_channels,
2 * residual_channels,
kernel_size=3,
padding=dilation,
dilation=dilation
)
self.diffusion_projection = nn.Linear(residual_channels, residual_channels)
self.conditioner_projection = nn.Conv1d(encoder_hidden, 2 * residual_channels, 1)
self.output_projection = nn.Conv1d(residual_channels, 2 * residual_channels, 1)
def forward(self, x, conditioner, diffusion_step):
diffusion_step = self.diffusion_projection(diffusion_step).unsqueeze(-1)
conditioner = self.conditioner_projection(conditioner)
y = x + diffusion_step
y = self.dilated_conv(y) + conditioner
# Using torch.split instead of torch.chunk to avoid using onnx::Slice
gate, filter = torch.split(y, [self.residual_channels, self.residual_channels], dim=1)
y = torch.sigmoid(gate) * torch.tanh(filter)
y = self.output_projection(y)
# Using torch.split instead of torch.chunk to avoid using onnx::Slice
residual, skip = torch.split(y, [self.residual_channels, self.residual_channels], dim=1)
return (x + residual) / math.sqrt(2.0), skip
class WaveNet(nn.Module):
def __init__(self, in_dims=128, n_layers=20, n_chans=384, n_hidden=256):
super().__init__()
self.input_projection = Conv1d(in_dims, n_chans, 1)
self.diffusion_embedding = SinusoidalPosEmb(n_chans)
self.mlp = nn.Sequential(
nn.Linear(n_chans, n_chans * 4),
Mish(),
nn.Linear(n_chans * 4, n_chans)
)
self.residual_layers = nn.ModuleList([
ResidualBlock(
encoder_hidden=n_hidden,
residual_channels=n_chans,
dilation=1
)
for i in range(n_layers)
])
self.skip_projection = Conv1d(n_chans, n_chans, 1)
self.output_projection = Conv1d(n_chans, in_dims, 1)
nn.init.zeros_(self.output_projection.weight)
def forward(self, spec, diffusion_step, cond):
"""
:param spec: [B, 1, M, T]
:param diffusion_step: [B, 1]
:param cond: [B, M, T]
:return:
"""
x = spec.squeeze(1)
x = self.input_projection(x) # [B, residual_channel, T]
x = F.relu(x)
diffusion_step = self.diffusion_embedding(diffusion_step)
diffusion_step = self.mlp(diffusion_step)
skip = []
for layer in self.residual_layers:
x, skip_connection = layer(x, cond, diffusion_step)
skip.append(skip_connection)
x = torch.sum(torch.stack(skip), dim=0) / sqrt(len(self.residual_layers))
x = self.skip_projection(x)
x = F.relu(x)
x = self.output_projection(x) # [B, mel_bins, T]
return x[:, None, :, :]