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- import math
- from functools import partial
- from typing import Any, Callable, List, Optional
- import torch
- import torch.nn.functional as F
- from torch import nn, Tensor
- from libs.vision_libs.models._api import register_model, Weights, WeightsEnum
- from libs.vision_libs.models._utils import _ovewrite_named_param, handle_legacy_interface
- from libs.vision_libs.transforms import InterpolationMode
- from libs.vision_libs.transforms._presets import ImageClassification
- from libs.vision_libs.utils import _log_api_usage_once
- from libs.vision_libs.ops import MLP,Permute
- from libs.vision_libs.ops.stochastic_depth import StochasticDepth
- from libs.vision_libs.models._meta import _IMAGENET_CATEGORIES
- __all__ = [
- "SwinTransformer",
- "Swin_T_Weights",
- "Swin_S_Weights",
- "Swin_B_Weights",
- "Swin_V2_T_Weights",
- "Swin_V2_S_Weights",
- "Swin_V2_B_Weights",
- "swin_t",
- "swin_s",
- "swin_b",
- "swin_v2_t",
- "swin_v2_s",
- "swin_v2_b",
- ]
- def _patch_merging_pad(x: torch.Tensor) -> torch.Tensor:
- H, W, _ = x.shape[-3:]
- x = F.pad(x, (0, 0, 0, W % 2, 0, H % 2))
- x0 = x[..., 0::2, 0::2, :] # ... H/2 W/2 C
- x1 = x[..., 1::2, 0::2, :] # ... H/2 W/2 C
- x2 = x[..., 0::2, 1::2, :] # ... H/2 W/2 C
- x3 = x[..., 1::2, 1::2, :] # ... H/2 W/2 C
- x = torch.cat([x0, x1, x2, x3], -1) # ... H/2 W/2 4*C
- return x
- torch.fx.wrap("_patch_merging_pad")
- def _get_relative_position_bias(
- relative_position_bias_table: torch.Tensor, relative_position_index: torch.Tensor, window_size: List[int]
- ) -> torch.Tensor:
- N = window_size[0] * window_size[1]
- relative_position_bias = relative_position_bias_table[relative_position_index] # type: ignore[index]
- relative_position_bias = relative_position_bias.view(N, N, -1)
- relative_position_bias = relative_position_bias.permute(2, 0, 1).contiguous().unsqueeze(0)
- return relative_position_bias
- torch.fx.wrap("_get_relative_position_bias")
- class PatchMerging(nn.Module):
- """Patch Merging Layer.
- Args:
- dim (int): Number of input channels.
- norm_layer (nn.Module): Normalization layer. Default: nn.LayerNorm.
- """
- def __init__(self, dim: int, norm_layer: Callable[..., nn.Module] = nn.LayerNorm):
- super().__init__()
- _log_api_usage_once(self)
- self.dim = dim
- self.reduction = nn.Linear(4 * dim, 2 * dim, bias=False)
- self.norm = norm_layer(4 * dim)
- def forward(self, x: Tensor):
- """
- Args:
- x (Tensor): input tensor with expected layout of [..., H, W, C]
- Returns:
- Tensor with layout of [..., H/2, W/2, 2*C]
- """
- x = _patch_merging_pad(x)
- x = self.norm(x)
- x = self.reduction(x) # ... H/2 W/2 2*C
- return x
- class PatchMergingV2(nn.Module):
- """Patch Merging Layer for Swin Transformer V2.
- Args:
- dim (int): Number of input channels.
- norm_layer (nn.Module): Normalization layer. Default: nn.LayerNorm.
- """
- def __init__(self, dim: int, norm_layer: Callable[..., nn.Module] = nn.LayerNorm):
- super().__init__()
- _log_api_usage_once(self)
- self.dim = dim
- self.reduction = nn.Linear(4 * dim, 2 * dim, bias=False)
- self.norm = norm_layer(2 * dim) # difference
- def forward(self, x: Tensor):
- """
- Args:
- x (Tensor): input tensor with expected layout of [..., H, W, C]
- Returns:
- Tensor with layout of [..., H/2, W/2, 2*C]
- """
- x = _patch_merging_pad(x)
- x = self.reduction(x) # ... H/2 W/2 2*C
- x = self.norm(x)
- return x
- def shifted_window_attention(
- input: Tensor,
- qkv_weight: Tensor,
- proj_weight: Tensor,
- relative_position_bias: Tensor,
- window_size: List[int],
- num_heads: int,
- shift_size: List[int],
- attention_dropout: float = 0.0,
- dropout: float = 0.0,
- qkv_bias: Optional[Tensor] = None,
- proj_bias: Optional[Tensor] = None,
- logit_scale: Optional[torch.Tensor] = None,
- training: bool = True,
- ) -> Tensor:
- """
- Window based multi-head self attention (W-MSA) module with relative position bias.
- It supports both of shifted and non-shifted window.
- Args:
- input (Tensor[N, H, W, C]): The input tensor or 4-dimensions.
- qkv_weight (Tensor[in_dim, out_dim]): The weight tensor of query, key, value.
- proj_weight (Tensor[out_dim, out_dim]): The weight tensor of projection.
- relative_position_bias (Tensor): The learned relative position bias added to attention.
- window_size (List[int]): Window size.
- num_heads (int): Number of attention heads.
- shift_size (List[int]): Shift size for shifted window attention.
- attention_dropout (float): Dropout ratio of attention weight. Default: 0.0.
- dropout (float): Dropout ratio of output. Default: 0.0.
- qkv_bias (Tensor[out_dim], optional): The bias tensor of query, key, value. Default: None.
- proj_bias (Tensor[out_dim], optional): The bias tensor of projection. Default: None.
- logit_scale (Tensor[out_dim], optional): Logit scale of cosine attention for Swin Transformer V2. Default: None.
- training (bool, optional): Training flag used by the dropout parameters. Default: True.
- Returns:
- Tensor[N, H, W, C]: The output tensor after shifted window attention.
- """
- B, H, W, C = input.shape
- # pad feature maps to multiples of window size
- pad_r = (window_size[1] - W % window_size[1]) % window_size[1]
- pad_b = (window_size[0] - H % window_size[0]) % window_size[0]
- x = F.pad(input, (0, 0, 0, pad_r, 0, pad_b))
- _, pad_H, pad_W, _ = x.shape
- shift_size = shift_size.copy()
- # If window size is larger than feature size, there is no need to shift window
- if window_size[0] >= pad_H:
- shift_size[0] = 0
- if window_size[1] >= pad_W:
- shift_size[1] = 0
- # cyclic shift
- if sum(shift_size) > 0:
- x = torch.roll(x, shifts=(-shift_size[0], -shift_size[1]), dims=(1, 2))
- # partition windows
- num_windows = (pad_H // window_size[0]) * (pad_W // window_size[1])
- x = x.view(B, pad_H // window_size[0], window_size[0], pad_W // window_size[1], window_size[1], C)
- x = x.permute(0, 1, 3, 2, 4, 5).reshape(B * num_windows, window_size[0] * window_size[1], C) # B*nW, Ws*Ws, C
- # multi-head attention
- if logit_scale is not None and qkv_bias is not None:
- qkv_bias = qkv_bias.clone()
- length = qkv_bias.numel() // 3
- qkv_bias[length : 2 * length].zero_()
- qkv = F.linear(x, qkv_weight, qkv_bias)
- qkv = qkv.reshape(x.size(0), x.size(1), 3, num_heads, C // num_heads).permute(2, 0, 3, 1, 4)
- q, k, v = qkv[0], qkv[1], qkv[2]
- if logit_scale is not None:
- # cosine attention
- attn = F.normalize(q, dim=-1) @ F.normalize(k, dim=-1).transpose(-2, -1)
- logit_scale = torch.clamp(logit_scale, max=math.log(100.0)).exp()
- attn = attn * logit_scale
- else:
- q = q * (C // num_heads) ** -0.5
- attn = q.matmul(k.transpose(-2, -1))
- # add relative position bias
- attn = attn + relative_position_bias
- if sum(shift_size) > 0:
- # generate attention ins
- attn_mask = x.new_zeros((pad_H, pad_W))
- h_slices = ((0, -window_size[0]), (-window_size[0], -shift_size[0]), (-shift_size[0], None))
- w_slices = ((0, -window_size[1]), (-window_size[1], -shift_size[1]), (-shift_size[1], None))
- count = 0
- for h in h_slices:
- for w in w_slices:
- attn_mask[h[0] : h[1], w[0] : w[1]] = count
- count += 1
- attn_mask = attn_mask.view(pad_H // window_size[0], window_size[0], pad_W // window_size[1], window_size[1])
- attn_mask = attn_mask.permute(0, 2, 1, 3).reshape(num_windows, window_size[0] * window_size[1])
- attn_mask = attn_mask.unsqueeze(1) - attn_mask.unsqueeze(2)
- attn_mask = attn_mask.masked_fill(attn_mask != 0, float(-100.0)).masked_fill(attn_mask == 0, float(0.0))
- attn = attn.view(x.size(0) // num_windows, num_windows, num_heads, x.size(1), x.size(1))
- attn = attn + attn_mask.unsqueeze(1).unsqueeze(0)
- attn = attn.view(-1, num_heads, x.size(1), x.size(1))
- attn = F.softmax(attn, dim=-1)
- attn = F.dropout(attn, p=attention_dropout, training=training)
- x = attn.matmul(v).transpose(1, 2).reshape(x.size(0), x.size(1), C)
- x = F.linear(x, proj_weight, proj_bias)
- x = F.dropout(x, p=dropout, training=training)
- # reverse windows
- x = x.view(B, pad_H // window_size[0], pad_W // window_size[1], window_size[0], window_size[1], C)
- x = x.permute(0, 1, 3, 2, 4, 5).reshape(B, pad_H, pad_W, C)
- # reverse cyclic shift
- if sum(shift_size) > 0:
- x = torch.roll(x, shifts=(shift_size[0], shift_size[1]), dims=(1, 2))
- # unpad features
- x = x[:, :H, :W, :].contiguous()
- return x
- torch.fx.wrap("shifted_window_attention")
- class ShiftedWindowAttention(nn.Module):
- """
- See :func:`shifted_window_attention`.
- """
- def __init__(
- self,
- dim: int,
- window_size: List[int],
- shift_size: List[int],
- num_heads: int,
- qkv_bias: bool = True,
- proj_bias: bool = True,
- attention_dropout: float = 0.0,
- dropout: float = 0.0,
- ):
- super().__init__()
- if len(window_size) != 2 or len(shift_size) != 2:
- raise ValueError("window_size and shift_size must be of length 2")
- self.window_size = window_size
- self.shift_size = shift_size
- self.num_heads = num_heads
- self.attention_dropout = attention_dropout
- self.dropout = dropout
- self.qkv = nn.Linear(dim, dim * 3, bias=qkv_bias)
- self.proj = nn.Linear(dim, dim, bias=proj_bias)
- self.define_relative_position_bias_table()
- self.define_relative_position_index()
- def define_relative_position_bias_table(self):
- # define a parameter table of relative position bias
- self.relative_position_bias_table = nn.Parameter(
- torch.zeros((2 * self.window_size[0] - 1) * (2 * self.window_size[1] - 1), self.num_heads)
- ) # 2*Wh-1 * 2*Ww-1, nH
- nn.init.trunc_normal_(self.relative_position_bias_table, std=0.02)
- def define_relative_position_index(self):
- # get pair-wise relative position index for each token inside the window
- coords_h = torch.arange(self.window_size[0])
- coords_w = torch.arange(self.window_size[1])
- coords = torch.stack(torch.meshgrid(coords_h, coords_w, indexing="ij")) # 2, Wh, Ww
- coords_flatten = torch.flatten(coords, 1) # 2, Wh*Ww
- relative_coords = coords_flatten[:, :, None] - coords_flatten[:, None, :] # 2, Wh*Ww, Wh*Ww
- relative_coords = relative_coords.permute(1, 2, 0).contiguous() # Wh*Ww, Wh*Ww, 2
- relative_coords[:, :, 0] += self.window_size[0] - 1 # shift to start from 0
- relative_coords[:, :, 1] += self.window_size[1] - 1
- relative_coords[:, :, 0] *= 2 * self.window_size[1] - 1
- relative_position_index = relative_coords.sum(-1).flatten() # Wh*Ww*Wh*Ww
- self.register_buffer("relative_position_index", relative_position_index)
- def get_relative_position_bias(self) -> torch.Tensor:
- return _get_relative_position_bias(
- self.relative_position_bias_table, self.relative_position_index, self.window_size # type: ignore[arg-type]
- )
- def forward(self, x: Tensor) -> Tensor:
- """
- Args:
- x (Tensor): Tensor with layout of [B, H, W, C]
- Returns:
- Tensor with same layout as input, i.e. [B, H, W, C]
- """
- relative_position_bias = self.get_relative_position_bias()
- return shifted_window_attention(
- x,
- self.qkv.weight,
- self.proj.weight,
- relative_position_bias,
- self.window_size,
- self.num_heads,
- shift_size=self.shift_size,
- attention_dropout=self.attention_dropout,
- dropout=self.dropout,
- qkv_bias=self.qkv.bias,
- proj_bias=self.proj.bias,
- training=self.training,
- )
- class ShiftedWindowAttentionV2(ShiftedWindowAttention):
- """
- See :func:`shifted_window_attention_v2`.
- """
- def __init__(
- self,
- dim: int,
- window_size: List[int],
- shift_size: List[int],
- num_heads: int,
- qkv_bias: bool = True,
- proj_bias: bool = True,
- attention_dropout: float = 0.0,
- dropout: float = 0.0,
- ):
- super().__init__(
- dim,
- window_size,
- shift_size,
- num_heads,
- qkv_bias=qkv_bias,
- proj_bias=proj_bias,
- attention_dropout=attention_dropout,
- dropout=dropout,
- )
- self.logit_scale = nn.Parameter(torch.log(10 * torch.ones((num_heads, 1, 1))))
- # mlp to generate continuous relative position bias
- self.cpb_mlp = nn.Sequential(
- nn.Linear(2, 512, bias=True), nn.ReLU(inplace=True), nn.Linear(512, num_heads, bias=False)
- )
- if qkv_bias:
- length = self.qkv.bias.numel() // 3
- self.qkv.bias[length : 2 * length].data.zero_()
- def define_relative_position_bias_table(self):
- # get relative_coords_table
- relative_coords_h = torch.arange(-(self.window_size[0] - 1), self.window_size[0], dtype=torch.float32)
- relative_coords_w = torch.arange(-(self.window_size[1] - 1), self.window_size[1], dtype=torch.float32)
- relative_coords_table = torch.stack(torch.meshgrid([relative_coords_h, relative_coords_w], indexing="ij"))
- relative_coords_table = relative_coords_table.permute(1, 2, 0).contiguous().unsqueeze(0) # 1, 2*Wh-1, 2*Ww-1, 2
- relative_coords_table[:, :, :, 0] /= self.window_size[0] - 1
- relative_coords_table[:, :, :, 1] /= self.window_size[1] - 1
- relative_coords_table *= 8 # normalize to -8, 8
- relative_coords_table = (
- torch.sign(relative_coords_table) * torch.log2(torch.abs(relative_coords_table) + 1.0) / 3.0
- )
- self.register_buffer("relative_coords_table", relative_coords_table)
- def get_relative_position_bias(self) -> torch.Tensor:
- relative_position_bias = _get_relative_position_bias(
- self.cpb_mlp(self.relative_coords_table).view(-1, self.num_heads),
- self.relative_position_index, # type: ignore[arg-type]
- self.window_size,
- )
- relative_position_bias = 16 * torch.sigmoid(relative_position_bias)
- return relative_position_bias
- def forward(self, x: Tensor):
- """
- Args:
- x (Tensor): Tensor with layout of [B, H, W, C]
- Returns:
- Tensor with same layout as input, i.e. [B, H, W, C]
- """
- relative_position_bias = self.get_relative_position_bias()
- return shifted_window_attention(
- x,
- self.qkv.weight,
- self.proj.weight,
- relative_position_bias,
- self.window_size,
- self.num_heads,
- shift_size=self.shift_size,
- attention_dropout=self.attention_dropout,
- dropout=self.dropout,
- qkv_bias=self.qkv.bias,
- proj_bias=self.proj.bias,
- logit_scale=self.logit_scale,
- training=self.training,
- )
- class SwinTransformerBlock(nn.Module):
- """
- Swin Transformer Block.
- Args:
- dim (int): Number of input channels.
- num_heads (int): Number of attention heads.
- window_size (List[int]): Window size.
- shift_size (List[int]): Shift size for shifted window attention.
- mlp_ratio (float): Ratio of mlp hidden dim to embedding dim. Default: 4.0.
- dropout (float): Dropout rate. Default: 0.0.
- attention_dropout (float): Attention dropout rate. Default: 0.0.
- stochastic_depth_prob: (float): Stochastic depth rate. Default: 0.0.
- norm_layer (nn.Module): Normalization layer. Default: nn.LayerNorm.
- attn_layer (nn.Module): Attention layer. Default: ShiftedWindowAttention
- """
- def __init__(
- self,
- dim: int,
- num_heads: int,
- window_size: List[int],
- shift_size: List[int],
- mlp_ratio: float = 4.0,
- dropout: float = 0.0,
- attention_dropout: float = 0.0,
- stochastic_depth_prob: float = 0.0,
- norm_layer: Callable[..., nn.Module] = nn.LayerNorm,
- attn_layer: Callable[..., nn.Module] = ShiftedWindowAttention,
- ):
- super().__init__()
- _log_api_usage_once(self)
- self.norm1 = norm_layer(dim)
- self.attn = attn_layer(
- dim,
- window_size,
- shift_size,
- num_heads,
- attention_dropout=attention_dropout,
- dropout=dropout,
- )
- self.stochastic_depth = StochasticDepth(stochastic_depth_prob, "row")
- self.norm2 = norm_layer(dim)
- self.mlp = MLP(dim, [int(dim * mlp_ratio), dim], activation_layer=nn.GELU, inplace=None, dropout=dropout)
- for m in self.mlp.modules():
- if isinstance(m, nn.Linear):
- nn.init.xavier_uniform_(m.weight)
- if m.bias is not None:
- nn.init.normal_(m.bias, std=1e-6)
- def forward(self, x: Tensor):
- x = x + self.stochastic_depth(self.attn(self.norm1(x)))
- x = x + self.stochastic_depth(self.mlp(self.norm2(x)))
- # x=x.permute(0, 3, 1, 2).contiguous()
- return x
- class SwinTransformerBlockV2(SwinTransformerBlock):
- """
- Swin Transformer V2 Block.
- Args:
- dim (int): Number of input channels.
- num_heads (int): Number of attention heads.
- window_size (List[int]): Window size.
- shift_size (List[int]): Shift size for shifted window attention.
- mlp_ratio (float): Ratio of mlp hidden dim to embedding dim. Default: 4.0.
- dropout (float): Dropout rate. Default: 0.0.
- attention_dropout (float): Attention dropout rate. Default: 0.0.
- stochastic_depth_prob: (float): Stochastic depth rate. Default: 0.0.
- norm_layer (nn.Module): Normalization layer. Default: nn.LayerNorm.
- attn_layer (nn.Module): Attention layer. Default: ShiftedWindowAttentionV2.
- """
- def __init__(
- self,
- dim: int,
- num_heads: int,
- window_size: List[int],
- shift_size: List[int],
- mlp_ratio: float = 4.0,
- dropout: float = 0.0,
- attention_dropout: float = 0.0,
- stochastic_depth_prob: float = 0.0,
- norm_layer: Callable[..., nn.Module] = nn.LayerNorm,
- attn_layer: Callable[..., nn.Module] = ShiftedWindowAttentionV2,
- ):
- super().__init__(
- dim,
- num_heads,
- window_size,
- shift_size,
- mlp_ratio=mlp_ratio,
- dropout=dropout,
- attention_dropout=attention_dropout,
- stochastic_depth_prob=stochastic_depth_prob,
- norm_layer=norm_layer,
- attn_layer=attn_layer,
- )
- def forward(self, x: Tensor):
- # Here is the difference, we apply norm after the attention in V2.
- # In V1 we applied norm before the attention.
- x = x + self.stochastic_depth(self.norm1(self.attn(x)))
- x = x + self.stochastic_depth(self.norm2(self.mlp(x)))
- return x
- class SwinTransformer(nn.Module):
- """
- Implements Swin Transformer from the `"Swin Transformer: Hierarchical Vision Transformer using
- Shifted Windows" <https://arxiv.org/abs/2103.14030>`_ paper.
- Args:
- patch_size (List[int]): Patch size.
- embed_dim (int): Patch embedding dimension.
- depths (List(int)): Depth of each Swin Transformer layer.
- num_heads (List(int)): Number of attention heads in different layers.
- window_size (List[int]): Window size.
- mlp_ratio (float): Ratio of mlp hidden dim to embedding dim. Default: 4.0.
- dropout (float): Dropout rate. Default: 0.0.
- attention_dropout (float): Attention dropout rate. Default: 0.0.
- stochastic_depth_prob (float): Stochastic depth rate. Default: 0.1.
- num_classes (int): Number of classes for classification head. Default: 1000.
- block (nn.Module, optional): SwinTransformer Block. Default: None.
- norm_layer (nn.Module, optional): Normalization layer. Default: None.
- downsample_layer (nn.Module): Downsample layer (patch merging). Default: PatchMerging.
- """
- def __init__(
- self,
- patch_size: List[int],
- embed_dim: int,
- depths: List[int],
- num_heads: List[int],
- window_size: List[int],
- mlp_ratio: float = 4.0,
- dropout: float = 0.0,
- attention_dropout: float = 0.0,
- stochastic_depth_prob: float = 0.1,
- num_classes: int = 1000,
- norm_layer: Optional[Callable[..., nn.Module]] = None,
- block: Optional[Callable[..., nn.Module]] = None,
- downsample_layer: Callable[..., nn.Module] = PatchMerging,
- ):
- super().__init__()
- _log_api_usage_once(self)
- self.num_classes = num_classes
- if block is None:
- block = SwinTransformerBlock
- if norm_layer is None:
- norm_layer = partial(nn.LayerNorm, eps=1e-5)
- layers: List[nn.Module] = []
- # split image into non-overlapping patches
- layers.append(
- nn.Sequential(
- nn.Conv2d(
- 3, embed_dim, kernel_size=(patch_size[0], patch_size[1]), stride=(patch_size[0], patch_size[1])
- ),
- Permute([0, 2, 3, 1]),
- norm_layer(embed_dim),
- )
- )
- total_stage_blocks = sum(depths)
- stage_block_id = 0
- # build SwinTransformer blocks
- for i_stage in range(len(depths)):
- stage: List[nn.Module] = []
- dim = embed_dim * 2**i_stage
- for i_layer in range(depths[i_stage]):
- # adjust stochastic depth probability based on the depth of the stage block
- sd_prob = stochastic_depth_prob * float(stage_block_id) / (total_stage_blocks - 1)
- stage.append(
- block(
- dim,
- num_heads[i_stage],
- window_size=window_size,
- shift_size=[0 if i_layer % 2 == 0 else w // 2 for w in window_size],
- mlp_ratio=mlp_ratio,
- dropout=dropout,
- attention_dropout=attention_dropout,
- stochastic_depth_prob=sd_prob,
- norm_layer=norm_layer,
- )
- )
- stage_block_id += 1
- layers.append(nn.Sequential(*stage))
- # add patch merging layer
- if i_stage < (len(depths) - 1):
- layers.append(downsample_layer(dim, norm_layer))
- self.features = nn.Sequential(*layers)
- num_features = embed_dim * 2 ** (len(depths) - 1)
- self.norm = norm_layer(num_features)
- self.permute = Permute([0, 3, 1, 2]) # B H W C -> B C H W
- self.avgpool = nn.AdaptiveAvgPool2d(1)
- self.flatten = nn.Flatten(1)
- self.head = nn.Linear(num_features, num_classes)
- for m in self.modules():
- if isinstance(m, nn.Linear):
- nn.init.trunc_normal_(m.weight, std=0.02)
- if m.bias is not None:
- nn.init.zeros_(m.bias)
- def forward(self, x):
- x = self.features(x)
- x = self.norm(x)
- x = self.permute(x)
- x = self.avgpool(x)
- x = self.flatten(x)
- x = self.head(x)
- return x
- def _swin_transformer(
- patch_size: List[int],
- embed_dim: int,
- depths: List[int],
- num_heads: List[int],
- window_size: List[int],
- stochastic_depth_prob: float,
- weights: Optional[WeightsEnum],
- progress: bool,
- **kwargs: Any,
- ) -> SwinTransformer:
- if weights is not None:
- _ovewrite_named_param(kwargs, "num_classes", len(weights.meta["categories"]))
- model = SwinTransformer(
- patch_size=patch_size,
- embed_dim=embed_dim,
- depths=depths,
- num_heads=num_heads,
- window_size=window_size,
- stochastic_depth_prob=stochastic_depth_prob,
- **kwargs,
- )
- if weights is not None:
- model.load_state_dict(weights.get_state_dict(progress=progress, check_hash=True))
- return model
- _COMMON_META = {
- "categories": _IMAGENET_CATEGORIES,
- }
- class Swin_T_Weights(WeightsEnum):
- IMAGENET1K_V1 = Weights(
- url="https://download.pytorch.org/models/swin_t-704ceda3.pth",
- transforms=partial(
- ImageClassification, crop_size=224, resize_size=232, interpolation=InterpolationMode.BICUBIC
- ),
- meta={
- **_COMMON_META,
- "num_params": 28288354,
- "min_size": (224, 224),
- "recipe": "https://github.com/pytorch/vision/tree/main/references/classification#swintransformer",
- "_metrics": {
- "ImageNet-1K": {
- "acc@1": 81.474,
- "acc@5": 95.776,
- }
- },
- "_ops": 4.491,
- "_file_size": 108.19,
- "_docs": """These weights reproduce closely the results of the paper using a similar training recipe.""",
- },
- )
- DEFAULT = IMAGENET1K_V1
- class Swin_S_Weights(WeightsEnum):
- IMAGENET1K_V1 = Weights(
- url="https://download.pytorch.org/models/swin_s-5e29d889.pth",
- transforms=partial(
- ImageClassification, crop_size=224, resize_size=246, interpolation=InterpolationMode.BICUBIC
- ),
- meta={
- **_COMMON_META,
- "num_params": 49606258,
- "min_size": (224, 224),
- "recipe": "https://github.com/pytorch/vision/tree/main/references/classification#swintransformer",
- "_metrics": {
- "ImageNet-1K": {
- "acc@1": 83.196,
- "acc@5": 96.360,
- }
- },
- "_ops": 8.741,
- "_file_size": 189.786,
- "_docs": """These weights reproduce closely the results of the paper using a similar training recipe.""",
- },
- )
- DEFAULT = IMAGENET1K_V1
- class Swin_B_Weights(WeightsEnum):
- IMAGENET1K_V1 = Weights(
- url="https://download.pytorch.org/models/swin_b-68c6b09e.pth",
- transforms=partial(
- ImageClassification, crop_size=224, resize_size=238, interpolation=InterpolationMode.BICUBIC
- ),
- meta={
- **_COMMON_META,
- "num_params": 87768224,
- "min_size": (224, 224),
- "recipe": "https://github.com/pytorch/vision/tree/main/references/classification#swintransformer",
- "_metrics": {
- "ImageNet-1K": {
- "acc@1": 83.582,
- "acc@5": 96.640,
- }
- },
- "_ops": 15.431,
- "_file_size": 335.364,
- "_docs": """These weights reproduce closely the results of the paper using a similar training recipe.""",
- },
- )
- DEFAULT = IMAGENET1K_V1
- class Swin_V2_T_Weights(WeightsEnum):
- IMAGENET1K_V1 = Weights(
- url="https://download.pytorch.org/models/swin_v2_t-b137f0e2.pth",
- transforms=partial(
- ImageClassification, crop_size=256, resize_size=260, interpolation=InterpolationMode.BICUBIC
- ),
- meta={
- **_COMMON_META,
- "num_params": 28351570,
- "min_size": (256, 256),
- "recipe": "https://github.com/pytorch/vision/tree/main/references/classification#swintransformer-v2",
- "_metrics": {
- "ImageNet-1K": {
- "acc@1": 82.072,
- "acc@5": 96.132,
- }
- },
- "_ops": 5.94,
- "_file_size": 108.626,
- "_docs": """These weights reproduce closely the results of the paper using a similar training recipe.""",
- },
- )
- DEFAULT = IMAGENET1K_V1
- class Swin_V2_S_Weights(WeightsEnum):
- IMAGENET1K_V1 = Weights(
- url="https://download.pytorch.org/models/swin_v2_s-637d8ceb.pth",
- transforms=partial(
- ImageClassification, crop_size=256, resize_size=260, interpolation=InterpolationMode.BICUBIC
- ),
- meta={
- **_COMMON_META,
- "num_params": 49737442,
- "min_size": (256, 256),
- "recipe": "https://github.com/pytorch/vision/tree/main/references/classification#swintransformer-v2",
- "_metrics": {
- "ImageNet-1K": {
- "acc@1": 83.712,
- "acc@5": 96.816,
- }
- },
- "_ops": 11.546,
- "_file_size": 190.675,
- "_docs": """These weights reproduce closely the results of the paper using a similar training recipe.""",
- },
- )
- DEFAULT = IMAGENET1K_V1
- class Swin_V2_B_Weights(WeightsEnum):
- IMAGENET1K_V1 = Weights(
- url="https://download.pytorch.org/models/swin_v2_b-781e5279.pth",
- transforms=partial(
- ImageClassification, crop_size=256, resize_size=272, interpolation=InterpolationMode.BICUBIC
- ),
- meta={
- **_COMMON_META,
- "num_params": 87930848,
- "min_size": (256, 256),
- "recipe": "https://github.com/pytorch/vision/tree/main/references/classification#swintransformer-v2",
- "_metrics": {
- "ImageNet-1K": {
- "acc@1": 84.112,
- "acc@5": 96.864,
- }
- },
- "_ops": 20.325,
- "_file_size": 336.372,
- "_docs": """These weights reproduce closely the results of the paper using a similar training recipe.""",
- },
- )
- DEFAULT = IMAGENET1K_V1
- def swin_t(*, weights: Optional[Swin_T_Weights] = None, progress: bool = True, **kwargs: Any) -> SwinTransformer:
- """
- Constructs a swin_tiny architecture from
- `Swin Transformer: Hierarchical Vision Transformer using Shifted Windows <https://arxiv.org/abs/2103.14030>`_.
- Args:
- weights (:class:`~torchvision.models.Swin_T_Weights`, optional): The
- pretrained weights to use. See
- :class:`~torchvision.models.Swin_T_Weights` below for
- more details, and possible values. By default, no pre-trained
- weights are used.
- progress (bool, optional): If True, displays a progress bar of the
- download to stderr. Default is True.
- **kwargs: parameters passed to the ``torchvision.models.swin_transformer.SwinTransformer``
- base class. Please refer to the `source code
- <https://github.com/pytorch/vision/blob/main/torchvision/models/swin_transformer.py>`_
- for more details about this class.
- .. autoclass:: torchvision.models.Swin_T_Weights
- :members:
- """
- weights = Swin_T_Weights.verify(weights)
- return _swin_transformer(
- patch_size=[1, 1],
- embed_dim=96,
- depths=[2, 2, 6, 2],
- num_heads=[3, 6, 12, 24],
- window_size=[7, 7],
- stochastic_depth_prob=0.2,
- weights=weights,
- progress=progress,
- **kwargs,
- )
- def swin_s(*, weights: Optional[Swin_S_Weights] = None, progress: bool = True, **kwargs: Any) -> SwinTransformer:
- """
- Constructs a swin_small architecture from
- `Swin Transformer: Hierarchical Vision Transformer using Shifted Windows <https://arxiv.org/abs/2103.14030>`_.
- Args:
- weights (:class:`~torchvision.models.Swin_S_Weights`, optional): The
- pretrained weights to use. See
- :class:`~torchvision.models.Swin_S_Weights` below for
- more details, and possible values. By default, no pre-trained
- weights are used.
- progress (bool, optional): If True, displays a progress bar of the
- download to stderr. Default is True.
- **kwargs: parameters passed to the ``torchvision.models.swin_transformer.SwinTransformer``
- base class. Please refer to the `source code
- <https://github.com/pytorch/vision/blob/main/torchvision/models/swin_transformer.py>`_
- for more details about this class.
- .. autoclass:: torchvision.models.Swin_S_Weights
- :members:
- """
- weights = Swin_S_Weights.verify(weights)
- return _swin_transformer(
- patch_size=[4, 4],
- embed_dim=96,
- depths=[2, 2, 18, 2],
- num_heads=[3, 6, 12, 24],
- window_size=[7, 7],
- stochastic_depth_prob=0.3,
- weights=weights,
- progress=progress,
- **kwargs,
- )
- def swin_b(*, weights: Optional[Swin_B_Weights] = None, progress: bool = True, **kwargs: Any) -> SwinTransformer:
- """
- Constructs a swin_base architecture from
- `Swin Transformer: Hierarchical Vision Transformer using Shifted Windows <https://arxiv.org/abs/2103.14030>`_.
- Args:
- weights (:class:`~torchvision.models.Swin_B_Weights`, optional): The
- pretrained weights to use. See
- :class:`~torchvision.models.Swin_B_Weights` below for
- more details, and possible values. By default, no pre-trained
- weights are used.
- progress (bool, optional): If True, displays a progress bar of the
- download to stderr. Default is True.
- **kwargs: parameters passed to the ``torchvision.models.swin_transformer.SwinTransformer``
- base class. Please refer to the `source code
- <https://github.com/pytorch/vision/blob/main/torchvision/models/swin_transformer.py>`_
- for more details about this class.
- .. autoclass:: torchvision.models.Swin_B_Weights
- :members:
- """
- weights = Swin_B_Weights.verify(weights)
- return _swin_transformer(
- patch_size=[4, 4],
- embed_dim=128,
- depths=[2, 2, 18, 2],
- num_heads=[4, 8, 16, 32],
- window_size=[7, 7],
- stochastic_depth_prob=0.5,
- weights=weights,
- progress=progress,
- **kwargs,
- )
- def swin_v2_t(*, weights: Optional[Swin_V2_T_Weights] = None, progress: bool = True, **kwargs: Any) -> SwinTransformer:
- """
- Constructs a swin_v2_tiny architecture from
- `Swin Transformer V2: Scaling Up Capacity and Resolution <https://arxiv.org/abs/2111.09883>`_.
- Args:
- weights (:class:`~torchvision.models.Swin_V2_T_Weights`, optional): The
- pretrained weights to use. See
- :class:`~torchvision.models.Swin_V2_T_Weights` below for
- more details, and possible values. By default, no pre-trained
- weights are used.
- progress (bool, optional): If True, displays a progress bar of the
- download to stderr. Default is True.
- **kwargs: parameters passed to the ``torchvision.models.swin_transformer.SwinTransformer``
- base class. Please refer to the `source code
- <https://github.com/pytorch/vision/blob/main/torchvision/models/swin_transformer.py>`_
- for more details about this class.
- .. autoclass:: torchvision.models.Swin_V2_T_Weights
- :members:
- """
- weights = Swin_V2_T_Weights.verify(weights)
- return _swin_transformer(
- patch_size=[2, 2],
- embed_dim=96,
- depths=[2, 2, 6, 2],
- num_heads=[3, 6, 12, 24],
- window_size=[8, 8],
- stochastic_depth_prob=0.2,
- weights=weights,
- progress=progress,
- block=SwinTransformerBlockV2,
- downsample_layer=PatchMergingV2,
- **kwargs,
- )
- def swin_v2_s(*, weights: Optional[Swin_V2_S_Weights] = None, progress: bool = True, **kwargs: Any) -> SwinTransformer:
- """
- Constructs a swin_v2_small architecture from
- `Swin Transformer V2: Scaling Up Capacity and Resolution <https://arxiv.org/abs/2111.09883>`_.
- Args:
- weights (:class:`~torchvision.models.Swin_V2_S_Weights`, optional): The
- pretrained weights to use. See
- :class:`~torchvision.models.Swin_V2_S_Weights` below for
- more details, and possible values. By default, no pre-trained
- weights are used.
- progress (bool, optional): If True, displays a progress bar of the
- download to stderr. Default is True.
- **kwargs: parameters passed to the ``torchvision.models.swin_transformer.SwinTransformer``
- base class. Please refer to the `source code
- <https://github.com/pytorch/vision/blob/main/torchvision/models/swin_transformer.py>`_
- for more details about this class.
- .. autoclass:: torchvision.models.Swin_V2_S_Weights
- :members:
- """
- weights = Swin_V2_S_Weights.verify(weights)
- return _swin_transformer(
- patch_size=[4, 4],
- embed_dim=96,
- depths=[2, 2, 18, 2],
- num_heads=[3, 6, 12, 24],
- window_size=[8, 8],
- stochastic_depth_prob=0.3,
- weights=weights,
- progress=progress,
- block=SwinTransformerBlockV2,
- downsample_layer=PatchMergingV2,
- **kwargs,
- )
- def swin_v2_b(*, weights: Optional[Swin_V2_B_Weights] = None, progress: bool = True, **kwargs: Any) -> SwinTransformer:
- """
- Constructs a swin_v2_base architecture from
- `Swin Transformer V2: Scaling Up Capacity and Resolution <https://arxiv.org/abs/2111.09883>`_.
- Args:
- weights (:class:`~torchvision.models.Swin_V2_B_Weights`, optional): The
- pretrained weights to use. See
- :class:`~torchvision.models.Swin_V2_B_Weights` below for
- more details, and possible values. By default, no pre-trained
- weights are used.
- progress (bool, optional): If True, displays a progress bar of the
- download to stderr. Default is True.
- **kwargs: parameters passed to the ``torchvision.models.swin_transformer.SwinTransformer``
- base class. Please refer to the `source code
- <https://github.com/pytorch/vision/blob/main/torchvision/models/swin_transformer.py>`_
- for more details about this class.
- .. autoclass:: torchvision.models.Swin_V2_B_Weights
- :members:
- """
- weights = Swin_V2_B_Weights.verify(weights)
- return _swin_transformer(
- patch_size=[4, 4],
- embed_dim=128,
- depths=[2, 2, 18, 2],
- num_heads=[4, 8, 16, 32],
- window_size=[8, 8],
- stochastic_depth_prob=0.5,
- weights=weights,
- progress=progress,
- block=SwinTransformerBlockV2,
- downsample_layer=PatchMergingV2,
- **kwargs,
- )
- if __name__ == '__main__':
- input=torch.randn(3,3,512,512)
- model=swin_v2_t(weights=None)
- out=model(input)
- print(f'out:{out.shape}')
|