Files
SISU/generator.py

127 lines
3.7 KiB
Python

import torch
import torch.nn as nn
from torch.nn.utils.parametrizations import weight_norm
def GeneratorBlock(in_channels, out_channels, kernel_size=3, stride=1, dilation=1):
padding = (kernel_size - 1) // 2 * dilation
return nn.Sequential(
weight_norm(nn.Conv1d(
in_channels,
out_channels,
kernel_size=kernel_size,
stride=stride,
dilation=dilation,
padding=padding
)),
nn.PReLU(num_parameters=1, init=0.1),
)
class AttentionBlock(nn.Module):
def __init__(self, channels):
super(AttentionBlock, self).__init__()
self.attention = nn.Sequential(
weight_norm(nn.Conv1d(channels, channels // 4, kernel_size=1)),
nn.ReLU(inplace=True),
weight_norm(nn.Conv1d(channels // 4, channels, kernel_size=1)),
nn.Sigmoid(),
)
def forward(self, x):
attention_weights = self.attention(x)
return x + (x * attention_weights)
class ResidualInResidualBlock(nn.Module):
def __init__(self, channels, num_convs=3):
super(ResidualInResidualBlock, self).__init__()
self.conv_layers = nn.Sequential(
*[GeneratorBlock(channels, channels) for _ in range(num_convs)]
)
self.attention = AttentionBlock(channels)
def forward(self, x):
residual = x
x = self.conv_layers(x)
x = self.attention(x)
return x + residual
def UpsampleBlock(in_channels, out_channels, scale_factor=2):
return nn.Sequential(
nn.Upsample(scale_factor=scale_factor, mode='nearest'),
weight_norm(nn.Conv1d(
in_channels=in_channels,
out_channels=out_channels,
kernel_size=3,
stride=1,
padding=1
)),
nn.PReLU(num_parameters=1, init=0.1)
)
class SISUGenerator(nn.Module):
def __init__(self, channels=32, num_rirb=4):
super(SISUGenerator, self).__init__()
self.first_conv = GeneratorBlock(1, channels)
self.downsample = GeneratorBlock(channels, channels * 2, stride=2)
self.downsample_attn = AttentionBlock(channels * 2)
self.downsample_2 = GeneratorBlock(channels * 2, channels * 4, stride=2)
self.downsample_2_attn = AttentionBlock(channels * 4)
self.rirb = nn.Sequential(
*[ResidualInResidualBlock(channels * 4) for _ in range(num_rirb)]
)
self.upsample = UpsampleBlock(channels * 4, channels * 2)
self.upsample_attn = AttentionBlock(channels * 2)
self.compress_1 = GeneratorBlock(channels * 4, channels * 2)
self.upsample_2 = UpsampleBlock(channels * 2, channels)
self.upsample_2_attn = AttentionBlock(channels)
self.compress_2 = GeneratorBlock(channels * 2, channels)
self.final_conv = nn.Sequential(
weight_norm(nn.Conv1d(channels, 1, kernel_size=7, padding=3)),
nn.Tanh()
)
def forward(self, x):
residual_input = x
# Encoding
x1 = self.first_conv(x)
x2 = self.downsample(x1)
x2 = self.downsample_attn(x2)
x3 = self.downsample_2(x2)
x3 = self.downsample_2_attn(x3)
# Bottleneck (Deep Residual processing)
x_rirb = self.rirb(x3)
# Decoding with Skip Connections
up1 = self.upsample(x_rirb)
up1 = self.upsample_attn(up1)
cat1 = torch.cat((up1, x2), dim=1)
comp1 = self.compress_1(cat1)
up2 = self.upsample_2(comp1)
up2 = self.upsample_2_attn(up2)
cat2 = torch.cat((up2, x1), dim=1)
comp2 = self.compress_2(cat2)
learned_residual = self.final_conv(comp2)
output = residual_input + learned_residual
return output