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-# -----------------------------------------------------------------------------------
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-# Swin2SR: Swin2SR: SwinV2 Transformer for Compressed Image Super-Resolution and Restoration, https://arxiv.org/abs/
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-# Written by Conde and Choi et al.
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-# -----------------------------------------------------------------------------------
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-
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-import math
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-import numpy as np
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-import torch
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-import torch.nn as nn
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-import torch.nn.functional as F
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-import torch.utils.checkpoint as checkpoint
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-from timm.models.layers import DropPath, to_2tuple, trunc_normal_
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-
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-
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-class Mlp(nn.Module):
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- def __init__(self, in_features, hidden_features=None, out_features=None, act_layer=nn.GELU, drop=0.):
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- super().__init__()
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- out_features = out_features or in_features
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- hidden_features = hidden_features or in_features
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- self.fc1 = nn.Linear(in_features, hidden_features)
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- self.act = act_layer()
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- self.fc2 = nn.Linear(hidden_features, out_features)
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- self.drop = nn.Dropout(drop)
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-
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- def forward(self, x):
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- x = self.fc1(x)
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- x = self.act(x)
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- x = self.drop(x)
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- x = self.fc2(x)
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- x = self.drop(x)
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- return x
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-
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-
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-def window_partition(x, window_size):
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- """
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- Args:
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- x: (B, H, W, C)
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- window_size (int): window size
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- Returns:
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- windows: (num_windows*B, window_size, window_size, C)
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- """
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- B, H, W, C = x.shape
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- x = x.view(B, H // window_size, window_size, W // window_size, window_size, C)
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- windows = x.permute(0, 1, 3, 2, 4, 5).contiguous().view(-1, window_size, window_size, C)
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- return windows
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-
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-
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-def window_reverse(windows, window_size, H, W):
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- """
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- Args:
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- windows: (num_windows*B, window_size, window_size, C)
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- window_size (int): Window size
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- H (int): Height of image
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- W (int): Width of image
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- Returns:
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- x: (B, H, W, C)
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- """
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- B = int(windows.shape[0] / (H * W / window_size / window_size))
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- x = windows.view(B, H // window_size, W // window_size, window_size, window_size, -1)
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- x = x.permute(0, 1, 3, 2, 4, 5).contiguous().view(B, H, W, -1)
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- return x
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-
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-class WindowAttention(nn.Module):
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- r""" Window based multi-head self attention (W-MSA) module with relative position bias.
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- It supports both of shifted and non-shifted window.
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- Args:
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- dim (int): Number of input channels.
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- window_size (tuple[int]): The height and width of the window.
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- num_heads (int): Number of attention heads.
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- qkv_bias (bool, optional): If True, add a learnable bias to query, key, value. Default: True
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- attn_drop (float, optional): Dropout ratio of attention weight. Default: 0.0
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- proj_drop (float, optional): Dropout ratio of output. Default: 0.0
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- pretrained_window_size (tuple[int]): The height and width of the window in pre-training.
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- """
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-
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- def __init__(self, dim, window_size, num_heads, qkv_bias=True, attn_drop=0., proj_drop=0.,
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- pretrained_window_size=(0, 0)):
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-
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- super().__init__()
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- self.dim = dim
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- self.window_size = window_size # Wh, Ww
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- self.pretrained_window_size = pretrained_window_size
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- self.num_heads = num_heads
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-
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- self.logit_scale = nn.Parameter(torch.log(10 * torch.ones((num_heads, 1, 1))), requires_grad=True)
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-
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- # mlp to generate continuous relative position bias
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- self.cpb_mlp = nn.Sequential(nn.Linear(2, 512, bias=True),
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- nn.ReLU(inplace=True),
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- nn.Linear(512, num_heads, bias=False))
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-
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- # get relative_coords_table
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- relative_coords_h = torch.arange(-(self.window_size[0] - 1), self.window_size[0], dtype=torch.float32)
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- relative_coords_w = torch.arange(-(self.window_size[1] - 1), self.window_size[1], dtype=torch.float32)
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- relative_coords_table = torch.stack(
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- torch.meshgrid([relative_coords_h,
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- relative_coords_w])).permute(1, 2, 0).contiguous().unsqueeze(0) # 1, 2*Wh-1, 2*Ww-1, 2
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- if pretrained_window_size[0] > 0:
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- relative_coords_table[:, :, :, 0] /= (pretrained_window_size[0] - 1)
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- relative_coords_table[:, :, :, 1] /= (pretrained_window_size[1] - 1)
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- else:
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- relative_coords_table[:, :, :, 0] /= (self.window_size[0] - 1)
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- relative_coords_table[:, :, :, 1] /= (self.window_size[1] - 1)
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- relative_coords_table *= 8 # normalize to -8, 8
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- relative_coords_table = torch.sign(relative_coords_table) * torch.log2(
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- torch.abs(relative_coords_table) + 1.0) / np.log2(8)
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-
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- self.register_buffer("relative_coords_table", relative_coords_table)
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-
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- # get pair-wise relative position index for each token inside the window
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- coords_h = torch.arange(self.window_size[0])
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- coords_w = torch.arange(self.window_size[1])
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- coords = torch.stack(torch.meshgrid([coords_h, coords_w])) # 2, Wh, Ww
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- coords_flatten = torch.flatten(coords, 1) # 2, Wh*Ww
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- relative_coords = coords_flatten[:, :, None] - coords_flatten[:, None, :] # 2, Wh*Ww, Wh*Ww
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- relative_coords = relative_coords.permute(1, 2, 0).contiguous() # Wh*Ww, Wh*Ww, 2
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- relative_coords[:, :, 0] += self.window_size[0] - 1 # shift to start from 0
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- relative_coords[:, :, 1] += self.window_size[1] - 1
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- relative_coords[:, :, 0] *= 2 * self.window_size[1] - 1
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- relative_position_index = relative_coords.sum(-1) # Wh*Ww, Wh*Ww
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- self.register_buffer("relative_position_index", relative_position_index)
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-
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- self.qkv = nn.Linear(dim, dim * 3, bias=False)
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- if qkv_bias:
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- self.q_bias = nn.Parameter(torch.zeros(dim))
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- self.v_bias = nn.Parameter(torch.zeros(dim))
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- else:
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- self.q_bias = None
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- self.v_bias = None
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- self.attn_drop = nn.Dropout(attn_drop)
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- self.proj = nn.Linear(dim, dim)
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- self.proj_drop = nn.Dropout(proj_drop)
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- self.softmax = nn.Softmax(dim=-1)
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-
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- def forward(self, x, mask=None):
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- """
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- Args:
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- x: input features with shape of (num_windows*B, N, C)
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- mask: (0/-inf) mask with shape of (num_windows, Wh*Ww, Wh*Ww) or None
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- """
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- B_, N, C = x.shape
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- qkv_bias = None
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- if self.q_bias is not None:
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- qkv_bias = torch.cat((self.q_bias, torch.zeros_like(self.v_bias, requires_grad=False), self.v_bias))
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- qkv = F.linear(input=x, weight=self.qkv.weight, bias=qkv_bias)
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- qkv = qkv.reshape(B_, N, 3, self.num_heads, -1).permute(2, 0, 3, 1, 4)
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- q, k, v = qkv[0], qkv[1], qkv[2] # make torchscript happy (cannot use tensor as tuple)
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-
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- # cosine attention
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- attn = (F.normalize(q, dim=-1) @ F.normalize(k, dim=-1).transpose(-2, -1))
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- logit_scale = torch.clamp(self.logit_scale, max=torch.log(torch.tensor(1. / 0.01)).to(self.logit_scale.device)).exp()
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- attn = attn * logit_scale
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-
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- relative_position_bias_table = self.cpb_mlp(self.relative_coords_table).view(-1, self.num_heads)
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- relative_position_bias = relative_position_bias_table[self.relative_position_index.view(-1)].view(
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- self.window_size[0] * self.window_size[1], self.window_size[0] * self.window_size[1], -1) # Wh*Ww,Wh*Ww,nH
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- relative_position_bias = relative_position_bias.permute(2, 0, 1).contiguous() # nH, Wh*Ww, Wh*Ww
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- relative_position_bias = 16 * torch.sigmoid(relative_position_bias)
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- attn = attn + relative_position_bias.unsqueeze(0)
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-
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- if mask is not None:
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- nW = mask.shape[0]
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- attn = attn.view(B_ // nW, nW, self.num_heads, N, N) + mask.unsqueeze(1).unsqueeze(0)
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- attn = attn.view(-1, self.num_heads, N, N)
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- attn = self.softmax(attn)
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- else:
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- attn = self.softmax(attn)
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-
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- attn = self.attn_drop(attn)
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-
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- x = (attn @ v).transpose(1, 2).reshape(B_, N, C)
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- x = self.proj(x)
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- x = self.proj_drop(x)
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- return x
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-
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- def extra_repr(self) -> str:
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- return f'dim={self.dim}, window_size={self.window_size}, ' \
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- f'pretrained_window_size={self.pretrained_window_size}, num_heads={self.num_heads}'
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-
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- def flops(self, N):
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- # calculate flops for 1 window with token length of N
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- flops = 0
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- # qkv = self.qkv(x)
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- flops += N * self.dim * 3 * self.dim
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- # attn = (q @ k.transpose(-2, -1))
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- flops += self.num_heads * N * (self.dim // self.num_heads) * N
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- # x = (attn @ v)
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- flops += self.num_heads * N * N * (self.dim // self.num_heads)
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- # x = self.proj(x)
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- flops += N * self.dim * self.dim
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- return flops
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-
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-class SwinTransformerBlock(nn.Module):
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- r""" Swin Transformer Block.
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- Args:
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- dim (int): Number of input channels.
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- input_resolution (tuple[int]): Input resulotion.
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- num_heads (int): Number of attention heads.
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- window_size (int): Window size.
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- shift_size (int): Shift size for SW-MSA.
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- mlp_ratio (float): Ratio of mlp hidden dim to embedding dim.
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- qkv_bias (bool, optional): If True, add a learnable bias to query, key, value. Default: True
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- drop (float, optional): Dropout rate. Default: 0.0
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- attn_drop (float, optional): Attention dropout rate. Default: 0.0
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- drop_path (float, optional): Stochastic depth rate. Default: 0.0
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- act_layer (nn.Module, optional): Activation layer. Default: nn.GELU
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- norm_layer (nn.Module, optional): Normalization layer. Default: nn.LayerNorm
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- pretrained_window_size (int): Window size in pre-training.
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- """
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-
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- def __init__(self, dim, input_resolution, num_heads, window_size=7, shift_size=0,
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- mlp_ratio=4., qkv_bias=True, drop=0., attn_drop=0., drop_path=0.,
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- act_layer=nn.GELU, norm_layer=nn.LayerNorm, pretrained_window_size=0):
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- super().__init__()
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- self.dim = dim
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- self.input_resolution = input_resolution
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- self.num_heads = num_heads
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- self.window_size = window_size
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- self.shift_size = shift_size
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- self.mlp_ratio = mlp_ratio
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- if min(self.input_resolution) <= self.window_size:
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- # if window size is larger than input resolution, we don't partition windows
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- self.shift_size = 0
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- self.window_size = min(self.input_resolution)
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- assert 0 <= self.shift_size < self.window_size, "shift_size must in 0-window_size"
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-
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- self.norm1 = norm_layer(dim)
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- self.attn = WindowAttention(
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- dim, window_size=to_2tuple(self.window_size), num_heads=num_heads,
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- qkv_bias=qkv_bias, attn_drop=attn_drop, proj_drop=drop,
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- pretrained_window_size=to_2tuple(pretrained_window_size))
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-
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- self.drop_path = DropPath(drop_path) if drop_path > 0. else nn.Identity()
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- self.norm2 = norm_layer(dim)
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- mlp_hidden_dim = int(dim * mlp_ratio)
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- self.mlp = Mlp(in_features=dim, hidden_features=mlp_hidden_dim, act_layer=act_layer, drop=drop)
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-
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- if self.shift_size > 0:
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- attn_mask = self.calculate_mask(self.input_resolution)
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- else:
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- attn_mask = None
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-
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- self.register_buffer("attn_mask", attn_mask)
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-
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- def calculate_mask(self, x_size):
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- # calculate attention mask for SW-MSA
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- H, W = x_size
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- img_mask = torch.zeros((1, H, W, 1)) # 1 H W 1
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- h_slices = (slice(0, -self.window_size),
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- slice(-self.window_size, -self.shift_size),
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- slice(-self.shift_size, None))
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- w_slices = (slice(0, -self.window_size),
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- slice(-self.window_size, -self.shift_size),
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- slice(-self.shift_size, None))
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- cnt = 0
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- for h in h_slices:
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- for w in w_slices:
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- img_mask[:, h, w, :] = cnt
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- cnt += 1
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-
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- mask_windows = window_partition(img_mask, self.window_size) # nW, window_size, window_size, 1
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- mask_windows = mask_windows.view(-1, self.window_size * self.window_size)
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- attn_mask = mask_windows.unsqueeze(1) - mask_windows.unsqueeze(2)
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- attn_mask = attn_mask.masked_fill(attn_mask != 0, float(-100.0)).masked_fill(attn_mask == 0, float(0.0))
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-
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- return attn_mask
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-
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- def forward(self, x, x_size):
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- H, W = x_size
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- B, L, C = x.shape
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- #assert L == H * W, "input feature has wrong size"
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-
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- shortcut = x
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- x = x.view(B, H, W, C)
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-
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- # cyclic shift
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- if self.shift_size > 0:
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- shifted_x = torch.roll(x, shifts=(-self.shift_size, -self.shift_size), dims=(1, 2))
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- else:
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- shifted_x = x
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-
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- # partition windows
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- x_windows = window_partition(shifted_x, self.window_size) # nW*B, window_size, window_size, C
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- x_windows = x_windows.view(-1, self.window_size * self.window_size, C) # nW*B, window_size*window_size, C
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-
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- # W-MSA/SW-MSA (to be compatible for testing on images whose shapes are the multiple of window size
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- if self.input_resolution == x_size:
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- attn_windows = self.attn(x_windows, mask=self.attn_mask) # nW*B, window_size*window_size, C
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- else:
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- attn_windows = self.attn(x_windows, mask=self.calculate_mask(x_size).to(x.device))
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-
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- # merge windows
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- attn_windows = attn_windows.view(-1, self.window_size, self.window_size, C)
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- shifted_x = window_reverse(attn_windows, self.window_size, H, W) # B H' W' C
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-
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- # reverse cyclic shift
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- if self.shift_size > 0:
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- x = torch.roll(shifted_x, shifts=(self.shift_size, self.shift_size), dims=(1, 2))
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- else:
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- x = shifted_x
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- x = x.view(B, H * W, C)
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- x = shortcut + self.drop_path(self.norm1(x))
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-
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- # FFN
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- x = x + self.drop_path(self.norm2(self.mlp(x)))
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-
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- return x
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-
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- def extra_repr(self) -> str:
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- return f"dim={self.dim}, input_resolution={self.input_resolution}, num_heads={self.num_heads}, " \
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- f"window_size={self.window_size}, shift_size={self.shift_size}, mlp_ratio={self.mlp_ratio}"
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-
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- def flops(self):
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- flops = 0
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- H, W = self.input_resolution
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- # norm1
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- flops += self.dim * H * W
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- # W-MSA/SW-MSA
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- nW = H * W / self.window_size / self.window_size
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- flops += nW * self.attn.flops(self.window_size * self.window_size)
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- # mlp
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- flops += 2 * H * W * self.dim * self.dim * self.mlp_ratio
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- # norm2
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- flops += self.dim * H * W
|
|
|
- return flops
|
|
|
-
|
|
|
-class PatchMerging(nn.Module):
|
|
|
- r""" Patch Merging Layer.
|
|
|
- Args:
|
|
|
- input_resolution (tuple[int]): Resolution of input feature.
|
|
|
- dim (int): Number of input channels.
|
|
|
- norm_layer (nn.Module, optional): Normalization layer. Default: nn.LayerNorm
|
|
|
- """
|
|
|
-
|
|
|
- def __init__(self, input_resolution, dim, norm_layer=nn.LayerNorm):
|
|
|
- super().__init__()
|
|
|
- self.input_resolution = input_resolution
|
|
|
- self.dim = dim
|
|
|
- self.reduction = nn.Linear(4 * dim, 2 * dim, bias=False)
|
|
|
- self.norm = norm_layer(2 * dim)
|
|
|
-
|
|
|
- def forward(self, x):
|
|
|
- """
|
|
|
- x: B, H*W, C
|
|
|
- """
|
|
|
- H, W = self.input_resolution
|
|
|
- B, L, C = x.shape
|
|
|
- assert L == H * W, "input feature has wrong size"
|
|
|
- assert H % 2 == 0 and W % 2 == 0, f"x size ({H}*{W}) are not even."
|
|
|
-
|
|
|
- x = x.view(B, H, W, C)
|
|
|
-
|
|
|
- x0 = x[:, 0::2, 0::2, :] # B H/2 W/2 C
|
|
|
- x1 = x[:, 1::2, 0::2, :] # B H/2 W/2 C
|
|
|
- x2 = x[:, 0::2, 1::2, :] # B H/2 W/2 C
|
|
|
- x3 = x[:, 1::2, 1::2, :] # B H/2 W/2 C
|
|
|
- x = torch.cat([x0, x1, x2, x3], -1) # B H/2 W/2 4*C
|
|
|
- x = x.view(B, -1, 4 * C) # B H/2*W/2 4*C
|
|
|
-
|
|
|
- x = self.reduction(x)
|
|
|
- x = self.norm(x)
|
|
|
-
|
|
|
- return x
|
|
|
-
|
|
|
- def extra_repr(self) -> str:
|
|
|
- return f"input_resolution={self.input_resolution}, dim={self.dim}"
|
|
|
-
|
|
|
- def flops(self):
|
|
|
- H, W = self.input_resolution
|
|
|
- flops = (H // 2) * (W // 2) * 4 * self.dim * 2 * self.dim
|
|
|
- flops += H * W * self.dim // 2
|
|
|
- return flops
|
|
|
-
|
|
|
-class BasicLayer(nn.Module):
|
|
|
- """ A basic Swin Transformer layer for one stage.
|
|
|
- Args:
|
|
|
- dim (int): Number of input channels.
|
|
|
- input_resolution (tuple[int]): Input resolution.
|
|
|
- depth (int): Number of blocks.
|
|
|
- num_heads (int): Number of attention heads.
|
|
|
- window_size (int): Local window size.
|
|
|
- mlp_ratio (float): Ratio of mlp hidden dim to embedding dim.
|
|
|
- qkv_bias (bool, optional): If True, add a learnable bias to query, key, value. Default: True
|
|
|
- drop (float, optional): Dropout rate. Default: 0.0
|
|
|
- attn_drop (float, optional): Attention dropout rate. Default: 0.0
|
|
|
- drop_path (float | tuple[float], optional): Stochastic depth rate. Default: 0.0
|
|
|
- norm_layer (nn.Module, optional): Normalization layer. Default: nn.LayerNorm
|
|
|
- downsample (nn.Module | None, optional): Downsample layer at the end of the layer. Default: None
|
|
|
- use_checkpoint (bool): Whether to use checkpointing to save memory. Default: False.
|
|
|
- pretrained_window_size (int): Local window size in pre-training.
|
|
|
- """
|
|
|
-
|
|
|
- def __init__(self, dim, input_resolution, depth, num_heads, window_size,
|
|
|
- mlp_ratio=4., qkv_bias=True, drop=0., attn_drop=0.,
|
|
|
- drop_path=0., norm_layer=nn.LayerNorm, downsample=None, use_checkpoint=False,
|
|
|
- pretrained_window_size=0):
|
|
|
-
|
|
|
- super().__init__()
|
|
|
- self.dim = dim
|
|
|
- self.input_resolution = input_resolution
|
|
|
- self.depth = depth
|
|
|
- self.use_checkpoint = use_checkpoint
|
|
|
-
|
|
|
- # build blocks
|
|
|
- self.blocks = nn.ModuleList([
|
|
|
- SwinTransformerBlock(dim=dim, input_resolution=input_resolution,
|
|
|
- num_heads=num_heads, window_size=window_size,
|
|
|
- shift_size=0 if (i % 2 == 0) else window_size // 2,
|
|
|
- mlp_ratio=mlp_ratio,
|
|
|
- qkv_bias=qkv_bias,
|
|
|
- drop=drop, attn_drop=attn_drop,
|
|
|
- drop_path=drop_path[i] if isinstance(drop_path, list) else drop_path,
|
|
|
- norm_layer=norm_layer,
|
|
|
- pretrained_window_size=pretrained_window_size)
|
|
|
- for i in range(depth)])
|
|
|
-
|
|
|
- # patch merging layer
|
|
|
- if downsample is not None:
|
|
|
- self.downsample = downsample(input_resolution, dim=dim, norm_layer=norm_layer)
|
|
|
- else:
|
|
|
- self.downsample = None
|
|
|
-
|
|
|
- def forward(self, x, x_size):
|
|
|
- for blk in self.blocks:
|
|
|
- if self.use_checkpoint:
|
|
|
- x = checkpoint.checkpoint(blk, x, x_size)
|
|
|
- else:
|
|
|
- x = blk(x, x_size)
|
|
|
- if self.downsample is not None:
|
|
|
- x = self.downsample(x)
|
|
|
- return x
|
|
|
-
|
|
|
- def extra_repr(self) -> str:
|
|
|
- return f"dim={self.dim}, input_resolution={self.input_resolution}, depth={self.depth}"
|
|
|
-
|
|
|
- def flops(self):
|
|
|
- flops = 0
|
|
|
- for blk in self.blocks:
|
|
|
- flops += blk.flops()
|
|
|
- if self.downsample is not None:
|
|
|
- flops += self.downsample.flops()
|
|
|
- return flops
|
|
|
-
|
|
|
- def _init_respostnorm(self):
|
|
|
- for blk in self.blocks:
|
|
|
- nn.init.constant_(blk.norm1.bias, 0)
|
|
|
- nn.init.constant_(blk.norm1.weight, 0)
|
|
|
- nn.init.constant_(blk.norm2.bias, 0)
|
|
|
- nn.init.constant_(blk.norm2.weight, 0)
|
|
|
-
|
|
|
-class PatchEmbed(nn.Module):
|
|
|
- r""" Image to Patch Embedding
|
|
|
- Args:
|
|
|
- img_size (int): Image size. Default: 224.
|
|
|
- patch_size (int): Patch token size. Default: 4.
|
|
|
- in_chans (int): Number of input image channels. Default: 3.
|
|
|
- embed_dim (int): Number of linear projection output channels. Default: 96.
|
|
|
- norm_layer (nn.Module, optional): Normalization layer. Default: None
|
|
|
- """
|
|
|
-
|
|
|
- def __init__(self, img_size=224, patch_size=4, in_chans=3, embed_dim=96, norm_layer=None):
|
|
|
- super().__init__()
|
|
|
- img_size = to_2tuple(img_size)
|
|
|
- patch_size = to_2tuple(patch_size)
|
|
|
- patches_resolution = [img_size[0] // patch_size[0], img_size[1] // patch_size[1]]
|
|
|
- self.img_size = img_size
|
|
|
- self.patch_size = patch_size
|
|
|
- self.patches_resolution = patches_resolution
|
|
|
- self.num_patches = patches_resolution[0] * patches_resolution[1]
|
|
|
-
|
|
|
- self.in_chans = in_chans
|
|
|
- self.embed_dim = embed_dim
|
|
|
-
|
|
|
- self.proj = nn.Conv2d(in_chans, embed_dim, kernel_size=patch_size, stride=patch_size)
|
|
|
- if norm_layer is not None:
|
|
|
- self.norm = norm_layer(embed_dim)
|
|
|
- else:
|
|
|
- self.norm = None
|
|
|
-
|
|
|
- def forward(self, x):
|
|
|
- B, C, H, W = x.shape
|
|
|
- # FIXME look at relaxing size constraints
|
|
|
- # assert H == self.img_size[0] and W == self.img_size[1],
|
|
|
- # f"Input image size ({H}*{W}) doesn't match model ({self.img_size[0]}*{self.img_size[1]})."
|
|
|
- x = self.proj(x).flatten(2).transpose(1, 2) # B Ph*Pw C
|
|
|
- if self.norm is not None:
|
|
|
- x = self.norm(x)
|
|
|
- return x
|
|
|
-
|
|
|
- def flops(self):
|
|
|
- Ho, Wo = self.patches_resolution
|
|
|
- flops = Ho * Wo * self.embed_dim * self.in_chans * (self.patch_size[0] * self.patch_size[1])
|
|
|
- if self.norm is not None:
|
|
|
- flops += Ho * Wo * self.embed_dim
|
|
|
- return flops
|
|
|
-
|
|
|
-class RSTB(nn.Module):
|
|
|
- """Residual Swin Transformer Block (RSTB).
|
|
|
-
|
|
|
- Args:
|
|
|
- dim (int): Number of input channels.
|
|
|
- input_resolution (tuple[int]): Input resolution.
|
|
|
- depth (int): Number of blocks.
|
|
|
- num_heads (int): Number of attention heads.
|
|
|
- window_size (int): Local window size.
|
|
|
- mlp_ratio (float): Ratio of mlp hidden dim to embedding dim.
|
|
|
- qkv_bias (bool, optional): If True, add a learnable bias to query, key, value. Default: True
|
|
|
- drop (float, optional): Dropout rate. Default: 0.0
|
|
|
- attn_drop (float, optional): Attention dropout rate. Default: 0.0
|
|
|
- drop_path (float | tuple[float], optional): Stochastic depth rate. Default: 0.0
|
|
|
- norm_layer (nn.Module, optional): Normalization layer. Default: nn.LayerNorm
|
|
|
- downsample (nn.Module | None, optional): Downsample layer at the end of the layer. Default: None
|
|
|
- use_checkpoint (bool): Whether to use checkpointing to save memory. Default: False.
|
|
|
- img_size: Input image size.
|
|
|
- patch_size: Patch size.
|
|
|
- resi_connection: The convolutional block before residual connection.
|
|
|
- """
|
|
|
-
|
|
|
- def __init__(self, dim, input_resolution, depth, num_heads, window_size,
|
|
|
- mlp_ratio=4., qkv_bias=True, drop=0., attn_drop=0.,
|
|
|
- drop_path=0., norm_layer=nn.LayerNorm, downsample=None, use_checkpoint=False,
|
|
|
- img_size=224, patch_size=4, resi_connection='1conv'):
|
|
|
- super(RSTB, self).__init__()
|
|
|
-
|
|
|
- self.dim = dim
|
|
|
- self.input_resolution = input_resolution
|
|
|
-
|
|
|
- self.residual_group = BasicLayer(dim=dim,
|
|
|
- input_resolution=input_resolution,
|
|
|
- depth=depth,
|
|
|
- num_heads=num_heads,
|
|
|
- window_size=window_size,
|
|
|
- mlp_ratio=mlp_ratio,
|
|
|
- qkv_bias=qkv_bias,
|
|
|
- drop=drop, attn_drop=attn_drop,
|
|
|
- drop_path=drop_path,
|
|
|
- norm_layer=norm_layer,
|
|
|
- downsample=downsample,
|
|
|
- use_checkpoint=use_checkpoint)
|
|
|
-
|
|
|
- if resi_connection == '1conv':
|
|
|
- self.conv = nn.Conv2d(dim, dim, 3, 1, 1)
|
|
|
- elif resi_connection == '3conv':
|
|
|
- # to save parameters and memory
|
|
|
- self.conv = nn.Sequential(nn.Conv2d(dim, dim // 4, 3, 1, 1), nn.LeakyReLU(negative_slope=0.2, inplace=True),
|
|
|
- nn.Conv2d(dim // 4, dim // 4, 1, 1, 0),
|
|
|
- nn.LeakyReLU(negative_slope=0.2, inplace=True),
|
|
|
- nn.Conv2d(dim // 4, dim, 3, 1, 1))
|
|
|
-
|
|
|
- self.patch_embed = PatchEmbed(
|
|
|
- img_size=img_size, patch_size=patch_size, in_chans=dim, embed_dim=dim,
|
|
|
- norm_layer=None)
|
|
|
-
|
|
|
- self.patch_unembed = PatchUnEmbed(
|
|
|
- img_size=img_size, patch_size=patch_size, in_chans=dim, embed_dim=dim,
|
|
|
- norm_layer=None)
|
|
|
-
|
|
|
- def forward(self, x, x_size):
|
|
|
- return self.patch_embed(self.conv(self.patch_unembed(self.residual_group(x, x_size), x_size))) + x
|
|
|
-
|
|
|
- def flops(self):
|
|
|
- flops = 0
|
|
|
- flops += self.residual_group.flops()
|
|
|
- H, W = self.input_resolution
|
|
|
- flops += H * W * self.dim * self.dim * 9
|
|
|
- flops += self.patch_embed.flops()
|
|
|
- flops += self.patch_unembed.flops()
|
|
|
-
|
|
|
- return flops
|
|
|
-
|
|
|
-class PatchUnEmbed(nn.Module):
|
|
|
- r""" Image to Patch Unembedding
|
|
|
-
|
|
|
- Args:
|
|
|
- img_size (int): Image size. Default: 224.
|
|
|
- patch_size (int): Patch token size. Default: 4.
|
|
|
- in_chans (int): Number of input image channels. Default: 3.
|
|
|
- embed_dim (int): Number of linear projection output channels. Default: 96.
|
|
|
- norm_layer (nn.Module, optional): Normalization layer. Default: None
|
|
|
- """
|
|
|
-
|
|
|
- def __init__(self, img_size=224, patch_size=4, in_chans=3, embed_dim=96, norm_layer=None):
|
|
|
- super().__init__()
|
|
|
- img_size = to_2tuple(img_size)
|
|
|
- patch_size = to_2tuple(patch_size)
|
|
|
- patches_resolution = [img_size[0] // patch_size[0], img_size[1] // patch_size[1]]
|
|
|
- self.img_size = img_size
|
|
|
- self.patch_size = patch_size
|
|
|
- self.patches_resolution = patches_resolution
|
|
|
- self.num_patches = patches_resolution[0] * patches_resolution[1]
|
|
|
-
|
|
|
- self.in_chans = in_chans
|
|
|
- self.embed_dim = embed_dim
|
|
|
-
|
|
|
- def forward(self, x, x_size):
|
|
|
- B, HW, C = x.shape
|
|
|
- x = x.transpose(1, 2).view(B, self.embed_dim, x_size[0], x_size[1]) # B Ph*Pw C
|
|
|
- return x
|
|
|
-
|
|
|
- def flops(self):
|
|
|
- flops = 0
|
|
|
- return flops
|
|
|
-
|
|
|
-
|
|
|
-class Upsample(nn.Sequential):
|
|
|
- """Upsample module.
|
|
|
-
|
|
|
- Args:
|
|
|
- scale (int): Scale factor. Supported scales: 2^n and 3.
|
|
|
- num_feat (int): Channel number of intermediate features.
|
|
|
- """
|
|
|
-
|
|
|
- def __init__(self, scale, num_feat):
|
|
|
- m = []
|
|
|
- if (scale & (scale - 1)) == 0: # scale = 2^n
|
|
|
- for _ in range(int(math.log(scale, 2))):
|
|
|
- m.append(nn.Conv2d(num_feat, 4 * num_feat, 3, 1, 1))
|
|
|
- m.append(nn.PixelShuffle(2))
|
|
|
- elif scale == 3:
|
|
|
- m.append(nn.Conv2d(num_feat, 9 * num_feat, 3, 1, 1))
|
|
|
- m.append(nn.PixelShuffle(3))
|
|
|
- else:
|
|
|
- raise ValueError(f'scale {scale} is not supported. ' 'Supported scales: 2^n and 3.')
|
|
|
- super(Upsample, self).__init__(*m)
|
|
|
-
|
|
|
-class Upsample_hf(nn.Sequential):
|
|
|
- """Upsample module.
|
|
|
-
|
|
|
- Args:
|
|
|
- scale (int): Scale factor. Supported scales: 2^n and 3.
|
|
|
- num_feat (int): Channel number of intermediate features.
|
|
|
- """
|
|
|
-
|
|
|
- def __init__(self, scale, num_feat):
|
|
|
- m = []
|
|
|
- if (scale & (scale - 1)) == 0: # scale = 2^n
|
|
|
- for _ in range(int(math.log(scale, 2))):
|
|
|
- m.append(nn.Conv2d(num_feat, 4 * num_feat, 3, 1, 1))
|
|
|
- m.append(nn.PixelShuffle(2))
|
|
|
- elif scale == 3:
|
|
|
- m.append(nn.Conv2d(num_feat, 9 * num_feat, 3, 1, 1))
|
|
|
- m.append(nn.PixelShuffle(3))
|
|
|
- else:
|
|
|
- raise ValueError(f'scale {scale} is not supported. ' 'Supported scales: 2^n and 3.')
|
|
|
- super(Upsample_hf, self).__init__(*m)
|
|
|
-
|
|
|
-
|
|
|
-class UpsampleOneStep(nn.Sequential):
|
|
|
- """UpsampleOneStep module (the difference with Upsample is that it always only has 1conv + 1pixelshuffle)
|
|
|
- Used in lightweight SR to save parameters.
|
|
|
-
|
|
|
- Args:
|
|
|
- scale (int): Scale factor. Supported scales: 2^n and 3.
|
|
|
- num_feat (int): Channel number of intermediate features.
|
|
|
-
|
|
|
- """
|
|
|
-
|
|
|
- def __init__(self, scale, num_feat, num_out_ch, input_resolution=None):
|
|
|
- self.num_feat = num_feat
|
|
|
- self.input_resolution = input_resolution
|
|
|
- m = []
|
|
|
- m.append(nn.Conv2d(num_feat, (scale ** 2) * num_out_ch, 3, 1, 1))
|
|
|
- m.append(nn.PixelShuffle(scale))
|
|
|
- super(UpsampleOneStep, self).__init__(*m)
|
|
|
-
|
|
|
- def flops(self):
|
|
|
- H, W = self.input_resolution
|
|
|
- flops = H * W * self.num_feat * 3 * 9
|
|
|
- return flops
|
|
|
-
|
|
|
-
|
|
|
-
|
|
|
-class Swin2SR(nn.Module):
|
|
|
- r""" Swin2SR
|
|
|
- A PyTorch impl of : `Swin2SR: SwinV2 Transformer for Compressed Image Super-Resolution and Restoration`.
|
|
|
-
|
|
|
- Args:
|
|
|
- img_size (int | tuple(int)): Input image size. Default 64
|
|
|
- patch_size (int | tuple(int)): Patch size. Default: 1
|
|
|
- in_chans (int): Number of input image channels. Default: 3
|
|
|
- embed_dim (int): Patch embedding dimension. Default: 96
|
|
|
- depths (tuple(int)): Depth of each Swin Transformer layer.
|
|
|
- num_heads (tuple(int)): Number of attention heads in different layers.
|
|
|
- window_size (int): Window size. Default: 7
|
|
|
- mlp_ratio (float): Ratio of mlp hidden dim to embedding dim. Default: 4
|
|
|
- qkv_bias (bool): If True, add a learnable bias to query, key, value. Default: True
|
|
|
- drop_rate (float): Dropout rate. Default: 0
|
|
|
- attn_drop_rate (float): Attention dropout rate. Default: 0
|
|
|
- drop_path_rate (float): Stochastic depth rate. Default: 0.1
|
|
|
- norm_layer (nn.Module): Normalization layer. Default: nn.LayerNorm.
|
|
|
- ape (bool): If True, add absolute position embedding to the patch embedding. Default: False
|
|
|
- patch_norm (bool): If True, add normalization after patch embedding. Default: True
|
|
|
- use_checkpoint (bool): Whether to use checkpointing to save memory. Default: False
|
|
|
- upscale: Upscale factor. 2/3/4/8 for image SR, 1 for denoising and compress artifact reduction
|
|
|
- img_range: Image range. 1. or 255.
|
|
|
- upsampler: The reconstruction reconstruction module. 'pixelshuffle'/'pixelshuffledirect'/'nearest+conv'/None
|
|
|
- resi_connection: The convolutional block before residual connection. '1conv'/'3conv'
|
|
|
- """
|
|
|
-
|
|
|
- def __init__(self, img_size=64, patch_size=1, in_chans=3,
|
|
|
- embed_dim=96, depths=(6, 6, 6, 6), num_heads=(6, 6, 6, 6),
|
|
|
- window_size=7, mlp_ratio=4., qkv_bias=True,
|
|
|
- drop_rate=0., attn_drop_rate=0., drop_path_rate=0.1,
|
|
|
- norm_layer=nn.LayerNorm, ape=False, patch_norm=True,
|
|
|
- use_checkpoint=False, upscale=2, img_range=1., upsampler='', resi_connection='1conv',
|
|
|
- **kwargs):
|
|
|
- super(Swin2SR, self).__init__()
|
|
|
- num_in_ch = in_chans
|
|
|
- num_out_ch = in_chans
|
|
|
- num_feat = 64
|
|
|
- self.img_range = img_range
|
|
|
- if in_chans == 3:
|
|
|
- rgb_mean = (0.4488, 0.4371, 0.4040)
|
|
|
- self.mean = torch.Tensor(rgb_mean).view(1, 3, 1, 1)
|
|
|
- else:
|
|
|
- self.mean = torch.zeros(1, 1, 1, 1)
|
|
|
- self.upscale = upscale
|
|
|
- self.upsampler = upsampler
|
|
|
- self.window_size = window_size
|
|
|
-
|
|
|
- #####################################################################################################
|
|
|
- ################################### 1, shallow feature extraction ###################################
|
|
|
- self.conv_first = nn.Conv2d(num_in_ch, embed_dim, 3, 1, 1)
|
|
|
-
|
|
|
- #####################################################################################################
|
|
|
- ################################### 2, deep feature extraction ######################################
|
|
|
- self.num_layers = len(depths)
|
|
|
- self.embed_dim = embed_dim
|
|
|
- self.ape = ape
|
|
|
- self.patch_norm = patch_norm
|
|
|
- self.num_features = embed_dim
|
|
|
- self.mlp_ratio = mlp_ratio
|
|
|
-
|
|
|
- # split image into non-overlapping patches
|
|
|
- self.patch_embed = PatchEmbed(
|
|
|
- img_size=img_size, patch_size=patch_size, in_chans=embed_dim, embed_dim=embed_dim,
|
|
|
- norm_layer=norm_layer if self.patch_norm else None)
|
|
|
- num_patches = self.patch_embed.num_patches
|
|
|
- patches_resolution = self.patch_embed.patches_resolution
|
|
|
- self.patches_resolution = patches_resolution
|
|
|
-
|
|
|
- # merge non-overlapping patches into image
|
|
|
- self.patch_unembed = PatchUnEmbed(
|
|
|
- img_size=img_size, patch_size=patch_size, in_chans=embed_dim, embed_dim=embed_dim,
|
|
|
- norm_layer=norm_layer if self.patch_norm else None)
|
|
|
-
|
|
|
- # absolute position embedding
|
|
|
- if self.ape:
|
|
|
- self.absolute_pos_embed = nn.Parameter(torch.zeros(1, num_patches, embed_dim))
|
|
|
- trunc_normal_(self.absolute_pos_embed, std=.02)
|
|
|
-
|
|
|
- self.pos_drop = nn.Dropout(p=drop_rate)
|
|
|
-
|
|
|
- # stochastic depth
|
|
|
- dpr = [x.item() for x in torch.linspace(0, drop_path_rate, sum(depths))] # stochastic depth decay rule
|
|
|
-
|
|
|
- # build Residual Swin Transformer blocks (RSTB)
|
|
|
- self.layers = nn.ModuleList()
|
|
|
- for i_layer in range(self.num_layers):
|
|
|
- layer = RSTB(dim=embed_dim,
|
|
|
- input_resolution=(patches_resolution[0],
|
|
|
- patches_resolution[1]),
|
|
|
- depth=depths[i_layer],
|
|
|
- num_heads=num_heads[i_layer],
|
|
|
- window_size=window_size,
|
|
|
- mlp_ratio=self.mlp_ratio,
|
|
|
- qkv_bias=qkv_bias,
|
|
|
- drop=drop_rate, attn_drop=attn_drop_rate,
|
|
|
- drop_path=dpr[sum(depths[:i_layer]):sum(depths[:i_layer + 1])], # no impact on SR results
|
|
|
- norm_layer=norm_layer,
|
|
|
- downsample=None,
|
|
|
- use_checkpoint=use_checkpoint,
|
|
|
- img_size=img_size,
|
|
|
- patch_size=patch_size,
|
|
|
- resi_connection=resi_connection
|
|
|
-
|
|
|
- )
|
|
|
- self.layers.append(layer)
|
|
|
-
|
|
|
- if self.upsampler == 'pixelshuffle_hf':
|
|
|
- self.layers_hf = nn.ModuleList()
|
|
|
- for i_layer in range(self.num_layers):
|
|
|
- layer = RSTB(dim=embed_dim,
|
|
|
- input_resolution=(patches_resolution[0],
|
|
|
- patches_resolution[1]),
|
|
|
- depth=depths[i_layer],
|
|
|
- num_heads=num_heads[i_layer],
|
|
|
- window_size=window_size,
|
|
|
- mlp_ratio=self.mlp_ratio,
|
|
|
- qkv_bias=qkv_bias,
|
|
|
- drop=drop_rate, attn_drop=attn_drop_rate,
|
|
|
- drop_path=dpr[sum(depths[:i_layer]):sum(depths[:i_layer + 1])], # no impact on SR results
|
|
|
- norm_layer=norm_layer,
|
|
|
- downsample=None,
|
|
|
- use_checkpoint=use_checkpoint,
|
|
|
- img_size=img_size,
|
|
|
- patch_size=patch_size,
|
|
|
- resi_connection=resi_connection
|
|
|
-
|
|
|
- )
|
|
|
- self.layers_hf.append(layer)
|
|
|
-
|
|
|
- self.norm = norm_layer(self.num_features)
|
|
|
-
|
|
|
- # build the last conv layer in deep feature extraction
|
|
|
- if resi_connection == '1conv':
|
|
|
- self.conv_after_body = nn.Conv2d(embed_dim, embed_dim, 3, 1, 1)
|
|
|
- elif resi_connection == '3conv':
|
|
|
- # to save parameters and memory
|
|
|
- self.conv_after_body = nn.Sequential(nn.Conv2d(embed_dim, embed_dim // 4, 3, 1, 1),
|
|
|
- nn.LeakyReLU(negative_slope=0.2, inplace=True),
|
|
|
- nn.Conv2d(embed_dim // 4, embed_dim // 4, 1, 1, 0),
|
|
|
- nn.LeakyReLU(negative_slope=0.2, inplace=True),
|
|
|
- nn.Conv2d(embed_dim // 4, embed_dim, 3, 1, 1))
|
|
|
-
|
|
|
- #####################################################################################################
|
|
|
- ################################ 3, high quality image reconstruction ################################
|
|
|
- if self.upsampler == 'pixelshuffle':
|
|
|
- # for classical SR
|
|
|
- self.conv_before_upsample = nn.Sequential(nn.Conv2d(embed_dim, num_feat, 3, 1, 1),
|
|
|
- nn.LeakyReLU(inplace=True))
|
|
|
- self.upsample = Upsample(upscale, num_feat)
|
|
|
- self.conv_last = nn.Conv2d(num_feat, num_out_ch, 3, 1, 1)
|
|
|
- elif self.upsampler == 'pixelshuffle_aux':
|
|
|
- self.conv_bicubic = nn.Conv2d(num_in_ch, num_feat, 3, 1, 1)
|
|
|
- self.conv_before_upsample = nn.Sequential(
|
|
|
- nn.Conv2d(embed_dim, num_feat, 3, 1, 1),
|
|
|
- nn.LeakyReLU(inplace=True))
|
|
|
- self.conv_aux = nn.Conv2d(num_feat, num_out_ch, 3, 1, 1)
|
|
|
- self.conv_after_aux = nn.Sequential(
|
|
|
- nn.Conv2d(3, num_feat, 3, 1, 1),
|
|
|
- nn.LeakyReLU(inplace=True))
|
|
|
- self.upsample = Upsample(upscale, num_feat)
|
|
|
- self.conv_last = nn.Conv2d(num_feat, num_out_ch, 3, 1, 1)
|
|
|
-
|
|
|
- elif self.upsampler == 'pixelshuffle_hf':
|
|
|
- self.conv_before_upsample = nn.Sequential(nn.Conv2d(embed_dim, num_feat, 3, 1, 1),
|
|
|
- nn.LeakyReLU(inplace=True))
|
|
|
- self.upsample = Upsample(upscale, num_feat)
|
|
|
- self.upsample_hf = Upsample_hf(upscale, num_feat)
|
|
|
- self.conv_last = nn.Conv2d(num_feat, num_out_ch, 3, 1, 1)
|
|
|
- self.conv_first_hf = nn.Sequential(nn.Conv2d(num_feat, embed_dim, 3, 1, 1),
|
|
|
- nn.LeakyReLU(inplace=True))
|
|
|
- self.conv_after_body_hf = nn.Conv2d(embed_dim, embed_dim, 3, 1, 1)
|
|
|
- self.conv_before_upsample_hf = nn.Sequential(
|
|
|
- nn.Conv2d(embed_dim, num_feat, 3, 1, 1),
|
|
|
- nn.LeakyReLU(inplace=True))
|
|
|
- self.conv_last_hf = nn.Conv2d(num_feat, num_out_ch, 3, 1, 1)
|
|
|
-
|
|
|
- elif self.upsampler == 'pixelshuffledirect':
|
|
|
- # for lightweight SR (to save parameters)
|
|
|
- self.upsample = UpsampleOneStep(upscale, embed_dim, num_out_ch,
|
|
|
- (patches_resolution[0], patches_resolution[1]))
|
|
|
- elif self.upsampler == 'nearest+conv':
|
|
|
- # for real-world SR (less artifacts)
|
|
|
- assert self.upscale == 4, 'only support x4 now.'
|
|
|
- self.conv_before_upsample = nn.Sequential(nn.Conv2d(embed_dim, num_feat, 3, 1, 1),
|
|
|
- nn.LeakyReLU(inplace=True))
|
|
|
- self.conv_up1 = nn.Conv2d(num_feat, num_feat, 3, 1, 1)
|
|
|
- self.conv_up2 = nn.Conv2d(num_feat, num_feat, 3, 1, 1)
|
|
|
- self.conv_hr = nn.Conv2d(num_feat, num_feat, 3, 1, 1)
|
|
|
- self.conv_last = nn.Conv2d(num_feat, num_out_ch, 3, 1, 1)
|
|
|
- self.lrelu = nn.LeakyReLU(negative_slope=0.2, inplace=True)
|
|
|
- else:
|
|
|
- # for image denoising and JPEG compression artifact reduction
|
|
|
- self.conv_last = nn.Conv2d(embed_dim, num_out_ch, 3, 1, 1)
|
|
|
-
|
|
|
- self.apply(self._init_weights)
|
|
|
-
|
|
|
- def _init_weights(self, m):
|
|
|
- if isinstance(m, nn.Linear):
|
|
|
- trunc_normal_(m.weight, std=.02)
|
|
|
- if isinstance(m, nn.Linear) and m.bias is not None:
|
|
|
- nn.init.constant_(m.bias, 0)
|
|
|
- elif isinstance(m, nn.LayerNorm):
|
|
|
- nn.init.constant_(m.bias, 0)
|
|
|
- nn.init.constant_(m.weight, 1.0)
|
|
|
-
|
|
|
- @torch.jit.ignore
|
|
|
- def no_weight_decay(self):
|
|
|
- return {'absolute_pos_embed'}
|
|
|
-
|
|
|
- @torch.jit.ignore
|
|
|
- def no_weight_decay_keywords(self):
|
|
|
- return {'relative_position_bias_table'}
|
|
|
-
|
|
|
- def check_image_size(self, x):
|
|
|
- _, _, h, w = x.size()
|
|
|
- mod_pad_h = (self.window_size - h % self.window_size) % self.window_size
|
|
|
- mod_pad_w = (self.window_size - w % self.window_size) % self.window_size
|
|
|
- x = F.pad(x, (0, mod_pad_w, 0, mod_pad_h), 'reflect')
|
|
|
- return x
|
|
|
-
|
|
|
- def forward_features(self, x):
|
|
|
- x_size = (x.shape[2], x.shape[3])
|
|
|
- x = self.patch_embed(x)
|
|
|
- if self.ape:
|
|
|
- x = x + self.absolute_pos_embed
|
|
|
- x = self.pos_drop(x)
|
|
|
-
|
|
|
- for layer in self.layers:
|
|
|
- x = layer(x, x_size)
|
|
|
-
|
|
|
- x = self.norm(x) # B L C
|
|
|
- x = self.patch_unembed(x, x_size)
|
|
|
-
|
|
|
- return x
|
|
|
-
|
|
|
- def forward_features_hf(self, x):
|
|
|
- x_size = (x.shape[2], x.shape[3])
|
|
|
- x = self.patch_embed(x)
|
|
|
- if self.ape:
|
|
|
- x = x + self.absolute_pos_embed
|
|
|
- x = self.pos_drop(x)
|
|
|
-
|
|
|
- for layer in self.layers_hf:
|
|
|
- x = layer(x, x_size)
|
|
|
-
|
|
|
- x = self.norm(x) # B L C
|
|
|
- x = self.patch_unembed(x, x_size)
|
|
|
-
|
|
|
- return x
|
|
|
-
|
|
|
- def forward(self, x):
|
|
|
- H, W = x.shape[2:]
|
|
|
- x = self.check_image_size(x)
|
|
|
-
|
|
|
- self.mean = self.mean.type_as(x)
|
|
|
- x = (x - self.mean) * self.img_range
|
|
|
-
|
|
|
- if self.upsampler == 'pixelshuffle':
|
|
|
- # for classical SR
|
|
|
- x = self.conv_first(x)
|
|
|
- x = self.conv_after_body(self.forward_features(x)) + x
|
|
|
- x = self.conv_before_upsample(x)
|
|
|
- x = self.conv_last(self.upsample(x))
|
|
|
- elif self.upsampler == 'pixelshuffle_aux':
|
|
|
- bicubic = F.interpolate(x, size=(H * self.upscale, W * self.upscale), mode='bicubic', align_corners=False)
|
|
|
- bicubic = self.conv_bicubic(bicubic)
|
|
|
- x = self.conv_first(x)
|
|
|
- x = self.conv_after_body(self.forward_features(x)) + x
|
|
|
- x = self.conv_before_upsample(x)
|
|
|
- aux = self.conv_aux(x) # b, 3, LR_H, LR_W
|
|
|
- x = self.conv_after_aux(aux)
|
|
|
- x = self.upsample(x)[:, :, :H * self.upscale, :W * self.upscale] + bicubic[:, :, :H * self.upscale, :W * self.upscale]
|
|
|
- x = self.conv_last(x)
|
|
|
- aux = aux / self.img_range + self.mean
|
|
|
- elif self.upsampler == 'pixelshuffle_hf':
|
|
|
- # for classical SR with HF
|
|
|
- x = self.conv_first(x)
|
|
|
- x = self.conv_after_body(self.forward_features(x)) + x
|
|
|
- x_before = self.conv_before_upsample(x)
|
|
|
- x_out = self.conv_last(self.upsample(x_before))
|
|
|
-
|
|
|
- x_hf = self.conv_first_hf(x_before)
|
|
|
- x_hf = self.conv_after_body_hf(self.forward_features_hf(x_hf)) + x_hf
|
|
|
- x_hf = self.conv_before_upsample_hf(x_hf)
|
|
|
- x_hf = self.conv_last_hf(self.upsample_hf(x_hf))
|
|
|
- x = x_out + x_hf
|
|
|
- x_hf = x_hf / self.img_range + self.mean
|
|
|
-
|
|
|
- elif self.upsampler == 'pixelshuffledirect':
|
|
|
- # for lightweight SR
|
|
|
- x = self.conv_first(x)
|
|
|
- x = self.conv_after_body(self.forward_features(x)) + x
|
|
|
- x = self.upsample(x)
|
|
|
- elif self.upsampler == 'nearest+conv':
|
|
|
- # for real-world SR
|
|
|
- x = self.conv_first(x)
|
|
|
- x = self.conv_after_body(self.forward_features(x)) + x
|
|
|
- x = self.conv_before_upsample(x)
|
|
|
- x = self.lrelu(self.conv_up1(torch.nn.functional.interpolate(x, scale_factor=2, mode='nearest')))
|
|
|
- x = self.lrelu(self.conv_up2(torch.nn.functional.interpolate(x, scale_factor=2, mode='nearest')))
|
|
|
- x = self.conv_last(self.lrelu(self.conv_hr(x)))
|
|
|
- else:
|
|
|
- # for image denoising and JPEG compression artifact reduction
|
|
|
- x_first = self.conv_first(x)
|
|
|
- res = self.conv_after_body(self.forward_features(x_first)) + x_first
|
|
|
- x = x + self.conv_last(res)
|
|
|
-
|
|
|
- x = x / self.img_range + self.mean
|
|
|
- if self.upsampler == "pixelshuffle_aux":
|
|
|
- return x[:, :, :H*self.upscale, :W*self.upscale], aux
|
|
|
-
|
|
|
- elif self.upsampler == "pixelshuffle_hf":
|
|
|
- x_out = x_out / self.img_range + self.mean
|
|
|
- return x_out[:, :, :H*self.upscale, :W*self.upscale], x[:, :, :H*self.upscale, :W*self.upscale], x_hf[:, :, :H*self.upscale, :W*self.upscale]
|
|
|
-
|
|
|
- else:
|
|
|
- return x[:, :, :H*self.upscale, :W*self.upscale]
|
|
|
-
|
|
|
- def flops(self):
|
|
|
- flops = 0
|
|
|
- H, W = self.patches_resolution
|
|
|
- flops += H * W * 3 * self.embed_dim * 9
|
|
|
- flops += self.patch_embed.flops()
|
|
|
- for layer in self.layers:
|
|
|
- flops += layer.flops()
|
|
|
- flops += H * W * 3 * self.embed_dim * self.embed_dim
|
|
|
- flops += self.upsample.flops()
|
|
|
- return flops
|
|
|
-
|
|
|
-
|
|
|
-if __name__ == '__main__':
|
|
|
- upscale = 4
|
|
|
- window_size = 8
|
|
|
- height = (1024 // upscale // window_size + 1) * window_size
|
|
|
- width = (720 // upscale // window_size + 1) * window_size
|
|
|
- model = Swin2SR(upscale=2, img_size=(height, width),
|
|
|
- window_size=window_size, img_range=1., depths=[6, 6, 6, 6],
|
|
|
- embed_dim=60, num_heads=[6, 6, 6, 6], mlp_ratio=2, upsampler='pixelshuffledirect')
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- print(model)
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- print(height, width, model.flops() / 1e9)
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-
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- x = torch.randn((1, 3, height, width))
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- x = model(x)
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- print(x.shape)
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Aarni Koskela