import torch import torch.nn as nn import torch.nn.functional as F from math import ceil from mamba_ssm import Mamba class Hamburger(nn.Module): def __init__(self, inp, oup, reduction=32): super(Hamburger, self).__init__() self.pool_h = nn.AdaptiveAvgPool3d((1, None, None)) self.pool_w = nn.AdaptiveAvgPool3d((None, 1, None)) self.pool_d = nn.AdaptiveAvgPool3d((None, None, 1)) mip = max(8, inp // reduction) self.conv1 = nn.Conv3d(inp, mip, kernel_size=1, stride=1, padding=0) self.conv2 = nn.Conv3d(inp, mip, kernel_size=1, stride=1, padding=0) self.conv3 = nn.Conv3d(inp, mip, kernel_size=1, stride=1, padding=0) self.gn1 = nn.GroupNorm(8, mip) self.gn2 = nn.GroupNorm(8, mip) self.gn3 = nn.GroupNorm(8, mip) self.act = nn.LeakyReLU(0.2) self.conv_h = nn.Conv3d(mip, oup, kernel_size=1, stride=1, padding=0) self.conv_w = nn.Conv3d(mip, oup, kernel_size=1, stride=1, padding=0) self.conv_d = nn.Conv3d(mip, oup, kernel_size=1, stride=1, padding=0) def forward(self, x): n, c, h, w, d = x.size() x_h = self.pool_h(x) # print(x_h.shape) x_w = self.pool_w(x).permute(0, 1, 3, 2, 4) # print(x_w.shape) x_d = self.pool_d(x).permute(0, 1, 4, 2, 3) # print(x_d.shape) y_hwd = torch.cat([x_h, x_w, x_d], dim=2) # y_hd = torch.cat([x_h, x_d], dim=2) # y_dw = torch.cat([x_d, x_w], dim=2) y_hwd = self.conv1(y_hwd) # y_hd = self.conv2(y_hd) # y_dw = self.conv3(y_dw) y_hwd = self.gn1(y_hwd) # y_hd = self.gn2(y_hd) # y_dw = self.gn3(y_dw) y_hwd = self.act(y_hwd) # y_hd = self.act(y_hd) # y_dw = self.act(y_dw) # print(y_hwd.shape) x_h, x_w, x_d = torch.split(y_hwd, [1, 1, 1], dim=2) x_w = x_w x_h = x_h.permute(0, 1, 3, 2, 4) x_d = x_d.permute(0, 1, 3, 4, 2) a_h = self.conv_h(x_h).sigmoid() a_w = self.conv_w(x_w).sigmoid() a_d = self.conv_d(x_d).sigmoid() a_hw = a_w * a_h out = a_hw * a_d return out + x class BasicBlock3D(nn.Module): expansion = 1 def __init__(self, in_channels, out_channels, stride=1, downsample=None): super(BasicBlock3D, self).__init__() self.conv1 = nn.Conv3d(in_channels, out_channels, kernel_size=3, stride=stride, padding=1, bias=False) self.bn1 = nn.BatchNorm3d(out_channels) self.relu = nn.ReLU(inplace=True) self.conv2 = nn.Conv3d(out_channels, out_channels, kernel_size=3, stride=1, padding=1, bias=False) self.bn2 = nn.BatchNorm3d(out_channels) self.downsample = downsample self.stride = stride def forward(self, x): identity = x out = self.conv1(x) out = self.bn1(out) out = self.relu(out) out = self.conv2(out) out = self.bn2(out) if self.downsample is not None: identity = self.downsample(x) out += identity out = self.relu(out) return out class Bottleneck3D(nn.Module): expansion = 4 def __init__(self, in_channels, out_channels, stride=1, downsample=None): super(Bottleneck3D, self).__init__() self.conv1 = nn.Conv3d(in_channels, out_channels, kernel_size=1, bias=False) self.bn1 = nn.BatchNorm3d(out_channels) self.conv2 = nn.Conv3d(out_channels, out_channels, kernel_size=3, stride=stride, padding=1, bias=False) self.bn2 = nn.BatchNorm3d(out_channels) self.conv3 = nn.Conv3d(out_channels, out_channels * self.expansion, kernel_size=1, bias=False) self.bn3 = nn.BatchNorm3d(out_channels * self.expansion) self.relu = nn.ReLU(inplace=True) self.downsample = downsample self.stride = stride def forward(self, x): identity = x out = self.conv1(x) out = self.bn1(out) out = self.relu(out) out = self.conv2(out) out = self.bn2(out) out = self.relu(out) out = self.conv3(out) out = self.bn3(out) if self.downsample is not None: identity = self.downsample(x) out += identity out = self.relu(out) return out class ResNet3D(nn.Module): def __init__(self, block, layers, input_channels=4, base_channels=16, feature_dim=512): super(ResNet3D, self).__init__() self.in_channels = base_channels self.conv1 = nn.Conv3d(input_channels, base_channels, kernel_size=7, stride=2, padding=3, bias=False) self.bn1 = nn.BatchNorm3d(base_channels) self.relu = nn.ReLU(inplace=True) self.maxpool = nn.MaxPool3d(kernel_size=3, stride=2, padding=1) # 每个layer的通道数是基于 base_channels 乘以扩展因子 self.layer1 = self._make_layer(block, base_channels, layers[0]) self.layer2 = self._make_layer(block, base_channels * 2, layers[1], stride=2) self.layer3 = self._make_layer(block, base_channels * 4, layers[2], stride=2) self.layer4 = self._make_layer(block, base_channels * 8, layers[3], stride=2) self.avgpool = nn.AdaptiveAvgPool3d((1, 1, 1)) self.fc = nn.Linear(base_channels * 8 * block.expansion, feature_dim) # 初始化权重 self._initialize_weights() def _make_layer(self, block, out_channels, blocks, stride=1): downsample = None if stride != 1 or self.in_channels != out_channels * block.expansion: downsample = nn.Sequential( nn.Conv3d(self.in_channels, out_channels * block.expansion, kernel_size=1, stride=stride, bias=False), nn.BatchNorm3d(out_channels * block.expansion), ) layers = [] layers.append(block(self.in_channels, out_channels, stride, downsample)) self.in_channels = out_channels * block.expansion for _ in range(1, blocks): layers.append(block(self.in_channels, out_channels)) return nn.Sequential(*layers) def _initialize_weights(self): for m in self.modules(): if isinstance(m, nn.Conv3d): nn.init.kaiming_normal_(m.weight, mode='fan_out', nonlinearity='relu') elif isinstance(m, (nn.BatchNorm3d, nn.GroupNorm)): nn.init.constant_(m.weight, 1) nn.init.constant_(m.bias, 0) elif isinstance(m, nn.Linear): nn.init.normal_(m.weight, 0, 0.01) nn.init.constant_(m.bias, 0) def forward(self, x): # Input shape: (B, C, D, H, W) x = self.conv1(x) x = self.bn1(x) x = self.relu(x) x = self.maxpool(x) x = self.layer1(x) # -> (B, C, D/4, H/4, W/4) x = self.layer2(x) # -> (B, 2C, D/8, H/8, W/8) x = self.layer3(x) # -> (B, 4C, D/16, H/16, W/16) x = self.layer4(x) # -> (B, 8C, D/32, H/32, W/32) x = self.avgpool(x) # -> (B, 8C, 1, 1, 1) x = torch.flatten(x, 1) # -> (B, 8C) x = self.fc(x) # -> (B, feature_dim) return x def ResNet3D34(input_channels=4, base_channels=16, feature_dim=512): """Constructs a ResNet-34 3D model.""" return ResNet3D(BasicBlock3D, [3, 4, 6, 3], input_channels=input_channels, base_channels=base_channels, feature_dim=feature_dim) def ResNet3D50(input_channels=4, base_channels=16, feature_dim=512): """Constructs a ResNet-50 3D model.""" return ResNet3D(Bottleneck3D, [3, 4, 6, 3], input_channels=input_channels, base_channels=base_channels, feature_dim=feature_dim) class DenseLayer3D(nn.Module): """DenseNet3D 的基本层,包括批归一化、激活和卷积操作""" def __init__(self, in_channels, growth_rate, bn_size=4, drop_rate=0.0): super(DenseLayer3D, self).__init__() self.bn1 = nn.BatchNorm3d(in_channels) self.relu = nn.ReLU(inplace=True) self.conv1 = nn.Conv3d(in_channels, bn_size * growth_rate, kernel_size=1, stride=1, bias=False) self.bn2 = nn.BatchNorm3d(bn_size * growth_rate) self.conv2 = nn.Conv3d(bn_size * growth_rate, growth_rate, kernel_size=3, stride=1, padding=1, bias=False) self.drop_rate = drop_rate def forward(self, x): out = self.bn1(x) out = self.relu(out) out = self.conv1(out) out = self.bn2(out) out = self.relu(out) out = self.conv2(out) if self.drop_rate > 0: out = F.dropout3d(out, p=self.drop_rate, training=self.training) # 将输入和输出在通道维度上拼接 out = torch.cat([x, out], 1) return out class DenseBlock3D(nn.Module): """由多个 DenseLayer3D 组成的 DenseBlock""" def __init__(self, num_layers, in_channels, growth_rate, bn_size=4, drop_rate=0.0): super(DenseBlock3D, self).__init__() layers = [] for i in range(num_layers): layers.append(DenseLayer3D( in_channels + i * growth_rate, growth_rate, bn_size=bn_size, drop_rate=drop_rate )) self.layer = nn.Sequential(*layers) def forward(self, x): return self.layer(x) class Transition3D(nn.Module): """用于减少特征图的尺寸和通道数的过渡层""" def __init__(self, in_channels, out_channels): super(Transition3D, self).__init__() self.bn = nn.BatchNorm3d(in_channels) self.relu = nn.ReLU(inplace=True) self.conv = nn.Conv3d(in_channels, out_channels, kernel_size=1, stride=1, bias=False) self.pool = nn.AvgPool3d(kernel_size=2, stride=2) def forward(self, x): out = self.bn(x) out = self.relu(out) out = self.conv(out) out = self.pool(out) return out class DenseNet3D(nn.Module): """DenseNet3D 模型""" def __init__(self, input_channels=1, base_channels=64, growth_rate=32, block_layers=[3, 6, 12, 8], bn_size=4, drop_rate=0.0, feature_dim=1024): super(DenseNet3D, self).__init__() self.growth_rate = growth_rate # 初始卷积层 self.features = nn.Sequential( nn.Conv3d(input_channels, base_channels, kernel_size=7, stride=2, padding=3, bias=False), nn.BatchNorm3d(base_channels), nn.ReLU(inplace=True), nn.MaxPool3d(kernel_size=3, stride=2, padding=1) ) # Dense Blocks 和 Transition Layers num_features = base_channels self.block_layers = [] self.num_blocks = len(block_layers) self.dense_blocks = nn.ModuleList() self.trans_blocks = nn.ModuleList() for i, num_layers in enumerate(block_layers): dense_block = DenseBlock3D( num_layers=num_layers, in_channels=num_features, growth_rate=growth_rate, bn_size=bn_size, drop_rate=drop_rate ) self.dense_blocks.append(dense_block) num_features = num_features + num_layers * growth_rate if i != self.num_blocks - 1: trans_block = Transition3D( in_channels=num_features, out_channels=num_features // 2 ) self.trans_blocks.append(trans_block) num_features = num_features // 2 # 最后一个 batch norm self.bn_final = nn.BatchNorm3d(num_features) self.relu_final = nn.ReLU(inplace=True) # 全局平均池化 self.global_pool = nn.AdaptiveAvgPool3d((1, 1, 1)) # 分类头 self.classifier = nn.Sequential( nn.Flatten(), nn.Linear(num_features, feature_dim) ) # 初始化权重 self._initialize_weights() def forward(self, x): out = self.features(x) for i in range(self.num_blocks): out = self.dense_blocks[i](out) if i < self.num_blocks - 1: out = self.trans_blocks[i](out) out = self.bn_final(out) out = self.relu_final(out) out = self.global_pool(out) # (B, C, 1, 1, 1) out = out.view(out.size(0), -1) # (B, C) out = self.classifier(out) # (B, feature_dim) return out def _initialize_weights(self): """初始化权重""" for m in self.modules(): if isinstance(m, nn.Conv3d): nn.init.kaiming_normal_(m.weight) elif isinstance(m, nn.BatchNorm3d): nn.init.constant_(m.weight, 1) nn.init.constant_(m.bias, 0) elif isinstance(m, nn.Linear): nn.init.normal_(m.weight, 0, 0.01) nn.init.constant_(m.bias, 0) class DepthwiseConv3D(nn.Module): """深度可分离卷积(3D)""" def __init__(self, dim, kernel_size=7, padding=3): super(DepthwiseConv3D, self).__init__() self.dw_conv = nn.Conv3d(dim, dim, kernel_size=kernel_size, padding=padding, groups=dim, bias=False) def forward(self, x): return self.dw_conv(x) class ConvNeXtBlock3D(nn.Module): """ConvNeXt 基本块(3D)""" def __init__(self, dim, drop_path=0.0): super(ConvNeXtBlock3D, self).__init__() self.depthwise_conv = DepthwiseConv3D(dim) self.norm = nn.LayerNorm(dim, eps=1e-6) self.pointwise_conv1 = nn.Linear(dim, 4 * dim) self.act = nn.GELU() self.pointwise_conv2 = nn.Linear(4 * dim, dim) self.drop_path = nn.Identity() if drop_path == 0.0 else nn.Dropout(drop_path) def forward(self, x): # 输入x形状: (B, C, D, H, W) residual = x x = self.depthwise_conv(x) # 转换为 (B, D, H, W, C) 以应用 LayerNorm 和 Linear x = x.permute(0, 2, 3, 4, 1) x = self.norm(x) x = self.pointwise_conv1(x) x = self.act(x) x = self.pointwise_conv2(x) x = self.drop_path(x) # 转换回 (B, C, D, H, W) x = x.permute(0, 4, 1, 2, 3) x = residual + x # 残差连接 return x class DownSample3D(nn.Module): """下采样层(3D)""" def __init__(self, in_channels, out_channels): super(DownSample3D, self).__init__() self.layer = nn.Sequential( nn.LayerNorm(in_channels, eps=1e-6), nn.Conv3d(in_channels, out_channels, kernel_size=2, stride=2) ) def forward(self, x): # 输入x形状: (B, C, D, H, W) # 需要在 LayerNorm 之前转换为 (B, D, H, W, C) x = x.permute(0, 2, 3, 4, 1) x = self.layer[0](x) # LayerNorm x = x.permute(0, 4, 1, 2, 3) # 转回 (B, C, D, H, W) x = self.layer[1](x) # Conv3d 下采样 return x class ConvNeXt3D(nn.Module): """ConvNeXt 模型(3D)""" def __init__(self, input_channels=3, base_channels=96, feature_dim=1024, depths=[3, 3, 9, 3], drop_path_rate=0.1, layer_scale_init_value=1e-6): super(ConvNeXt3D, self).__init__() self.num_stages = len(depths) self.drop_path_rate = drop_path_rate # 计算每个阶段的通道数 self.dims = [base_channels * (2 ** i) for i in range(self.num_stages)] # Stem 层:卷积下采样 self.stem = nn.Sequential( nn.Conv3d(input_channels, self.dims[0], kernel_size=4, stride=4), nn.LayerNorm(self.dims[0], eps=1e-6) ) # 将每个阶段的块和下采样层组合 self.stages = nn.ModuleList() self.downsamples = nn.ModuleList() total_blocks = sum(depths) # 为 DropPath 计算每个块的丢弃概率 dpr = [x.item() for x in torch.linspace(0, drop_path_rate, total_blocks)] block_idx = 0 for i in range(self.num_stages): # ConvNeXt 块 stage = nn.Sequential( *[ConvNeXtBlock3D(dim=self.dims[i], drop_path=dpr[block_idx + j]) for j in range(depths[i])] ) self.stages.append(stage) block_idx += depths[i] # 下采样层(除最后一个阶段外) if i < self.num_stages - 1: self.downsamples.append(DownSample3D(self.dims[i], self.dims[i+1])) # 全局池化和分类头 self.global_pool = nn.AdaptiveAvgPool3d(1) self.norm_head = nn.LayerNorm(self.dims[-1], eps=1e-6) self.flatten = nn.Flatten() self.fc = nn.Linear(self.dims[-1], feature_dim) def forward(self, x): # Stem 层 x = self.stem(x) # 各个阶段 for i in range(self.num_stages): x = self.stages[i](x) if i < self.num_stages - 1: x = self.downsamples[i](x) # 全局池化 x = self.global_pool(x) # (B, C, 1, 1, 1) x = x.view(x.shape[0], x.shape[1]) # (B, C) x = self.norm_head(x) # LayerNorm x = self.flatten(x) # (B, C) x = self.fc(x) # (B, feature_dim) return x class PatchEmbed3D(nn.Module): """3D Patch Embedding Layer""" def __init__(self, input_channels=4, embed_dim=16, patch_size=(4, 8, 8)): super(PatchEmbed3D, self).__init__() self.patch_size = patch_size # (D, H, W) self.proj = nn.Conv3d( input_channels, embed_dim, kernel_size=patch_size, stride=patch_size ) self.norm = nn.LayerNorm(embed_dim) def forward(self, x): # x: (B, C, D, H, W) x = self.proj(x) # (B, embed_dim, D', H', W') B, C, D, H, W = x.shape x = x.permute(0, 2, 3, 4, 1) # (B, D', H', W', C) x = x.reshape(B, D * H * W, C) # (B, N, C), N = D'*H'*W' = (64/4)*(64/8)*(64/8)=16*8*8=1024 x = self.norm(x) return x # (B, N, C) class TransformerEncoderLayer3D(nn.Module): """Standard Transformer Encoder Layer for 3D ViT""" def __init__(self, embed_dim, num_heads, mlp_ratio=4.0, drop=0.0, attn_drop=0.0): super(TransformerEncoderLayer3D, self).__init__() self.norm1 = nn.LayerNorm(embed_dim) self.attn = nn.MultiheadAttention(embed_dim, num_heads, dropout=attn_drop, batch_first=True) self.drop1 = nn.Dropout(drop) self.norm2 = nn.LayerNorm(embed_dim) hidden_dim = int(embed_dim * mlp_ratio) self.mlp = nn.Sequential( nn.Linear(embed_dim, hidden_dim), nn.GELU(), nn.Dropout(drop), nn.Linear(hidden_dim, embed_dim), nn.Dropout(drop) ) def forward(self, x): # x: (B, N, C) x2 = self.norm1(x) attn_output, _ = self.attn(x2, x2, x2) # attn_output: (B, N, C) x = x + self.drop1(attn_output) x2 = self.norm2(x) x = x + self.mlp(x2) return x # (B, N, C) class TransformerEncoder3D(nn.Module): """Transformer Encoder consisting of multiple TransformerEncoderLayer3D""" def __init__(self, depth, embed_dim, num_heads, mlp_ratio=4.0, drop=0.0, attn_drop=0.0): super(TransformerEncoder3D, self).__init__() self.layers = nn.ModuleList([ TransformerEncoderLayer3D(embed_dim, num_heads, mlp_ratio, drop, attn_drop) for _ in range(depth) ]) self.norm = nn.LayerNorm(embed_dim) def forward(self, x): for layer in self.layers: x = layer(x) x = self.norm(x) return x # (B, N, C) class VisionTransformer3D(nn.Module): """3D Vision Transformer (ViT)""" def __init__(self, input_channels=4, base_channels=16, feature_dim=512, patch_size=(8, 8, 8), depth=4, num_heads=4, mlp_ratio=4.0, drop_rate=0.1, attn_drop_rate=0.1): super(VisionTransformer3D, self).__init__() self.patch_embed = PatchEmbed3D(input_channels, base_channels, patch_size) # Calculate number of patches D_patch, H_patch, W_patch = patch_size self.num_patches = (64 // D_patch) * (64 // H_patch) * (64 // W_patch) # 8*8*8=512 # CLS token self.cls_token = nn.Parameter(torch.zeros(1, 1, base_channels)) # Position Embedding self.pos_embed = nn.Parameter(torch.zeros(1, self.num_patches + 1, base_channels)) self.pos_drop = nn.Dropout(p=drop_rate) # Transformer Encoder self.encoder = TransformerEncoder3D(depth, base_channels, num_heads, mlp_ratio, drop_rate, attn_drop_rate) # Classification head self.norm_head = nn.LayerNorm(base_channels) self.fc = nn.Linear(base_channels, feature_dim) self._init_weights() def _init_weights(self): nn.init.trunc_normal_(self.pos_embed, std=0.02) nn.init.trunc_normal_(self.cls_token, std=0.02) nn.init.xavier_uniform_(self.fc.weight) nn.init.constant_(self.fc.bias, 0) def forward(self, x): # x: (B, C, D, H, W) B = x.shape[0] x = self.patch_embed(x) # (B, N, C) # Expand CLS token cls_tokens = self.cls_token.expand(B, -1, -1) # (B, 1, C) x = torch.cat((cls_tokens, x), dim=1) # (B, N+1, C) x = x + self.pos_embed # (B, N+1, C) x = self.pos_drop(x) x = self.encoder(x) # (B, N+1, C) cls_token_final = x[:, 0] # (B, C) cls_token_final = self.norm_head(cls_token_final) # (B, C) features = self.fc(cls_token_final) # (B, feature_dim) return features # (B, feature_dim) class SwinPatchEmbed3D(nn.Module): """将3D输入分割成patches并进行嵌入""" def __init__(self, patch_size=(4, 4, 4), in_channels=4, embed_dim=16): super(SwinPatchEmbed3D, self).__init__() self.patch_size = patch_size self.proj = nn.Conv3d(in_channels, embed_dim, kernel_size=patch_size, stride=patch_size) def forward(self, x): # x shape: (B, C, D, H, W) B, C, D, H, W = x.shape x = self.proj(x) # (B, embed_dim, D/p, H/p, W/p) x = x.flatten(2).transpose(1, 2) # (B, num_patches, embed_dim) D_p, H_p, W_p = x.shape[1] // (H // self.patch_size[1] * W // self.patch_size[2]), H // self.patch_size[1], W // self.patch_size[2] return x, (D_p, H_p, W_p) class WindowAttention3D(nn.Module): """3D窗口多头自注意力""" def __init__(self, dim, window_size=(7, 7, 7), num_heads=8, qkv_bias=True, attn_drop=0., proj_drop=0.): super(WindowAttention3D, self).__init__() self.dim = dim self.window_size = window_size # (Wd, Wh, Ww) self.num_heads = num_heads head_dim = dim // num_heads self.scale = head_dim ** -0.5 # 相对位置编码 self.relative_position_bias_table = nn.Parameter( torch.zeros( (2 * window_size[0] - 1) * (2 * window_size[1] - 1) * (2 * window_size[2] - 1), num_heads ) ) # 每个相对位置一个bias # 生成相对位置的index coords_d = torch.arange(window_size[0]) coords_h = torch.arange(window_size[1]) coords_w = torch.arange(window_size[2]) coords = torch.stack(torch.meshgrid(coords_d, coords_h, coords_w, indexing='ij')) # 3, Wd, Wh, Ww coords_flatten = torch.flatten(coords, 1) # 3, Wd*Wh*Ww relative_coords = coords_flatten[:, :, None] - coords_flatten[:, None, :] # 3, Wd*Wh*Ww, Wd*Wh*Ww relative_coords = relative_coords.permute(1, 2, 0).contiguous() # Wd*Wh*Ww, Wd*Wh*Ww, 3 relative_coords += torch.tensor(self.window_size) - 1 # shift to start from 0 relative_coords[:, :, 0] *= (2 * window_size[1] - 1) * (2 * window_size[2] - 1) relative_coords[:, :, 1] *= (2 * window_size[2] - 1) relative_position_index = relative_coords.sum(-1) # Wd*Wh*Ww, Wd*Wh*Ww self.register_buffer("relative_position_index", relative_position_index) self.qkv = nn.Linear(dim, dim * 3, bias=qkv_bias) self.attn_drop = nn.Dropout(attn_drop) self.proj = nn.Linear(dim, dim) self.proj_drop = nn.Dropout(proj_drop) nn.init.trunc_normal_(self.relative_position_bias_table, std=0.02) def forward(self, x, mask=None): """ x: (num_windows*B, N, C) mask: (num_windows, N, N) or None """ B_, N, C = x.shape qkv = self.qkv(x).reshape(B_, N, 3, self.num_heads, C // self.num_heads).permute(2, 0, 3, 1, 4) # qkv shape: (3, B_, num_heads, N, head_dim) q, k, v = qkv[0], qkv[1], qkv[2] # each: (B_, num_heads, N, head_dim) q = q * self.scale attn = (q @ k.transpose(-2, -1)) # (B_, num_heads, N, N) # 添加相对位置编码 relative_position_bias = self.relative_position_bias_table[self.relative_position_index.view(-1)].view( N, N, -1 ) # (N, N, num_heads) relative_position_bias = relative_position_bias.permute(2, 0, 1).contiguous() # (num_heads, N, N) attn = attn + relative_position_bias.unsqueeze(0) if mask is not None: nW = mask.shape[0] attn = attn.view(B_ // nW, nW, self.num_heads, N, N) + mask.unsqueeze(1).unsqueeze(0) attn = attn.view(-1, self.num_heads, N, N) attn = F.softmax(attn, dim=-1) else: attn = F.softmax(attn, dim=-1) attn = self.attn_drop(attn) out = (attn @ v) # (B_, num_heads, N, head_dim) out = out.transpose(1, 2).reshape(B_, N, C) # (B_, N, C) out = self.proj(out) out = self.proj_drop(out) return out class SwinTransformerBlock3D(nn.Module): """3D Swin Transformer Block""" def __init__(self, dim, num_heads, window_size=(7, 7, 7), shift_size=(0, 0, 0), mlp_ratio=4., qkv_bias=True, drop=0., attn_drop=0., drop_path=0.): super(SwinTransformerBlock3D, self).__init__() self.dim = dim self.num_heads = num_heads self.window_size = window_size # Wd, Wh, Ww self.shift_size = shift_size # Wd_shift, Wh_shift, Ww_shift self.mlp_ratio = mlp_ratio self.norm1 = nn.LayerNorm(dim) self.attn = WindowAttention3D(dim, window_size, num_heads, qkv_bias, attn_drop, drop) self.drop_path = nn.Identity() if drop_path == 0 else nn.Dropout(drop_path) self.norm2 = nn.LayerNorm(dim) mlp_hidden_dim = int(dim * mlp_ratio) self.mlp = nn.Sequential( nn.Linear(dim, mlp_hidden_dim), nn.GELU(), nn.Dropout(drop), nn.Linear(mlp_hidden_dim, dim), nn.Dropout(drop) ) @staticmethod def window_partition(x, window_size): """ 将输入x (B, D, H, W, C) 分割成窗口 返回: windows (num_windows*B, window_size D, window_size H, window_size W, C) """ B, D, H, W, C = x.shape x = x.view( B, D // window_size[0], window_size[0], H // window_size[1], window_size[1], W // window_size[2], window_size[2], C ) windows = x.permute(0, 1, 3, 5, 2, 4, 6, 7).contiguous().view(-1, *window_size, C) return windows @staticmethod def window_reverse(windows, window_size, B, D, H, W): """ 将窗口逆操作合并回原始特征图 Input: windows: (num_windows*B, window_size D, window_size H, window_size W, C) window_size: tuple (Wd, Wh, Ww) B, D, H, W: 原始体数据的维度 Output: x: (B, D, H, W, C) """ C = windows.shape[-1] x = windows.view( B, D // window_size[0], H // window_size[1], W // window_size[2], window_size[0], window_size[1], window_size[2], C ) x = x.permute(0, 1, 2, 3, 4, 5, 6, 7).contiguous().view(B, D, H, W, C) return x def create_attn_mask(self, input_resolution): """创建注意力掩码,用于处理移动窗口边界""" D, H, W = input_resolution img_mask = torch.zeros((1, D, H, W, 1), device=self.attn.relative_position_bias_table.device) # (1, D, H, W, 1) Wd, Wh, Ww = self.window_size sd, sh, sw = self.shift_size # 计算每个区块的位置标记 cnt = 0 for d in (slice(0, -Wd), slice(-Wd, -sd) if sd > 0 else slice(0, None), slice(-sd, None) if sd > 0 else slice(0, None)): for h in (slice(0, -Wh), slice(-Wh, -sh) if sh > 0 else slice(0, None), slice(-sh, None) if sh > 0 else slice(0, None)): for w in (slice(0, -Ww), slice(-Ww, -sw) if sw > 0 else slice(0, None), slice(-sw, None) if sw > 0 else slice(0, None)): img_mask[:, d, h, w, :] = cnt cnt += 1 # 分割为窗口 mask_windows = self.window_partition(img_mask, self.window_size) # (num_windows, Wd, Wh, Ww, 1) mask_windows = mask_windows.view(-1, Wd * Wh * Ww) attn_mask = mask_windows.unsqueeze(1) - mask_windows.unsqueeze(2) attn_mask = attn_mask.masked_fill(attn_mask != 0, float(-100.0)).masked_fill(attn_mask == 0, float(0.0)) return attn_mask def forward(self, x, input_resolution): """ x: (B, N, C), N = D*H*W input_resolution: tuple (D, H, W) """ D, H, W = input_resolution B, N, C = x.shape assert N == D * H * W, "Input has incorrect size" shortcut = x x = self.norm1(x) x = x.view(B, D, H, W, C) # 1. Shift if any(s > 0 for s in self.shift_size): shifted_x = torch.roll(x, shifts=(-self.shift_size[0], -self.shift_size[1], -self.shift_size[2]), dims=(1, 2, 3)) else: shifted_x = x # 2. Window partition x_windows = self.window_partition(shifted_x, self.window_size) # (num_windows*B, Wd, Wh, Ww, C) x_windows = x_windows.view(-1, self.window_size[0] * self.window_size[1] * self.window_size[2], C) # (num_windows*B, Nw, C) # 3. Window Multi-Head Self-Attention if any(s > 0 for s in self.shift_size): attn_mask = self.create_attn_mask(input_resolution) else: attn_mask = None attn_windows = self.attn(x_windows, mask=attn_mask) # (num_windows*B, Nw, C) # 4. Merge windows attn_windows = attn_windows.view(-1, *self.window_size, C) shifted_x = self.window_reverse(attn_windows, self.window_size, B, D, H, W) # (B, D, H, W, C) # 5. Reverse shift if any(s > 0 for s in self.shift_size): x = torch.roll(shifted_x, shifts=(self.shift_size[0], self.shift_size[1], self.shift_size[2]), dims=(1, 2, 3)) else: x = shifted_x x = x.view(B, D * H * W, C) # 6. MLP x = shortcut + self.drop_path(x) x = x + self.drop_path(self.mlp(self.norm2(x))) return x class PatchMerging3D(nn.Module): """3D Patch Merging""" def __init__(self, dim): super(PatchMerging3D, self).__init__() self.dim = dim self.reduction = nn.Linear(dim * 8, 2 * dim, bias=False) # 2x reduction in resolution self.norm = nn.LayerNorm(dim * 8) def forward(self, x, input_resolution): # x: (B, N, C), N = D*H*W B, N, C = x.shape D, H, W = input_resolution assert N == D * H * W, "Input has incorrect size" x = x.view(B, D, H, W, C) # 2x2x2_merge for D, H, W x0 = x[:, 0::2, 0::2, 0::2, :] # (B, D/2, H/2, W/2, C) x1 = x[:, 1::2, 0::2, 0::2, :] x2 = x[:, 0::2, 1::2, 0::2, :] x3 = x[:, 0::2, 0::2, 1::2, :] x4 = x[:, 1::2, 1::2, 0::2, :] x5 = x[:, 1::2, 0::2, 1::2, :] x6 = x[:, 0::2, 1::2, 1::2, :] x7 = x[:, 1::2, 1::2, 1::2, :] x = torch.cat([x0, x1, x2, x3, x4, x5, x6, x7], -1) # (B, D/2, H/2, W/2, 8*C) x = x.view(B, -1, 8 * C) # (B, D/2 * H/2 * W/2, 8*C) x = self.norm(x) x = self.reduction(x) # (B, D/2 * H/2 * W/2, 2*C) return x class SwinTransformerStage3D(nn.Module): """一个Swin Transformer阶段,包括多个Block和Patch Merging""" def __init__(self, dim, depth, num_heads, window_size=(7, 7, 7), mlp_ratio=4., qkv_bias=True, drop=0., attn_drop=0., drop_path=None, downsample=True): super(SwinTransformerStage3D, self).__init__() self.blocks = nn.ModuleList() for i in range(depth): shift_size = ( window_size[0] // 2 if (i % 2 == 1 and window_size[0] > 1) else 0, window_size[1] // 2 if (i % 2 == 1 and window_size[1] > 1) else 0, window_size[2] // 2 if (i % 2 == 1 and window_size[2] > 1) else 0, ) block = SwinTransformerBlock3D( dim=dim, num_heads=num_heads, window_size=window_size, shift_size=shift_size, 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 ) self.blocks.append(block) self.downsample = PatchMerging3D(dim) if downsample else None def forward(self, x, input_resolution): """ x: (B, N, C) input_resolution: tuple (D, H, W) """ for blk in self.blocks: x = blk(x, input_resolution) if self.downsample: x = self.downsample(x, input_resolution) D, H, W = input_resolution input_resolution = (D // 2, H // 2, W // 2) return x, input_resolution class SwinTransformer3D(nn.Module): """3D Swin Transformer模型""" def __init__(self, input_channels=4, base_channels=16, feature_dim=512, patch_size=(4, 4, 4), depths=[2, 2, 6, 2], num_heads=[2, 4, 8, 16], window_size=(2, 2, 2), mlp_ratio=4., qkv_bias=True, drop_rate=0., attn_drop_rate=0., drop_path_rate=0.1): super(SwinTransformer3D, self).__init__() self.num_layers = len(depths) self.embed_dim = base_channels self.patch_size = patch_size self.patch_embed = SwinPatchEmbed3D(patch_size, in_channels=input_channels, embed_dim=self.embed_dim) # 计算drop path率 total_depth = sum(depths) dpr = [x.item() for x in torch.linspace(0, drop_path_rate, total_depth)] self.layers = nn.ModuleList() current_depth = 0 for i_layer in range(self.num_layers): layer = SwinTransformerStage3D( dim=base_channels * 2**i_layer, depth=depths[i_layer], num_heads=num_heads[i_layer], window_size=window_size, mlp_ratio=mlp_ratio, qkv_bias=qkv_bias, drop=drop_rate, attn_drop=attn_drop_rate, drop_path=dpr[current_depth:current_depth + depths[i_layer]], downsample=(i_layer < self.num_layers - 1) ) self.layers.append(layer) current_depth += depths[i_layer] self.norm = nn.LayerNorm(base_channels * 2**(self.num_layers - 1)) self.avgpool = nn.AdaptiveAvgPool1d(1) self.head = nn.Linear(base_channels * 2**(self.num_layers - 1), feature_dim) def forward_features(self, x): """ x: (B, C, D, H, W) """ x, input_resolution = self.patch_embed(x) # (B, num_patches, embed_dim), (D_p, H_p, W_p) for layer in self.layers: x, input_resolution = layer(x, input_resolution) x = self.norm(x) # (B, num_patches, dim) return x def forward(self, x): """ x: (B, C, D, H, W) """ x = self.forward_features(x) # (B, num_patches, dim) x = x.transpose(1, 2) # (B, dim, num_patches) x = self.avgpool(x).squeeze(-1) # (B, dim) x = self.head(x) # (B, feature_dim) return x class VoxPeptide(nn.Module): def __init__(self, v_encoder='resnet34', classes=6, channels=16, in_channels=4): super().__init__() self.classes = classes if v_encoder == 'resnet34': self.v_encoder = ResNet3D34(input_channels=in_channels, base_channels=channels, feature_dim=512) elif v_encoder == 'resnet50': self.v_encoder = ResNet3D50(input_channels=in_channels, base_channels=channels, feature_dim=512) elif v_encoder == 'densenet': self.v_encoder = DenseNet3D(input_channels=in_channels, base_channels=channels, growth_rate=16 if channels < 48 else 32, feature_dim=512) elif v_encoder == 'convnext': self.v_encoder = ConvNeXt3D(input_channels=in_channels, base_channels=channels, feature_dim=512) elif v_encoder == 'vit': self.v_encoder = VisionTransformer3D(input_channels=in_channels, base_channels=channels, feature_dim=512) elif v_encoder == 'swintf': self.v_encoder = SwinTransformer3D(input_channels=in_channels, base_channels=channels, feature_dim=512) else: raise NotImplementedError(f'\'{v_encoder}\' not implemented') self.vox_fc = nn.Linear(512, classes) def forward(self, x): vox, seq = x seq_emb = self.v_encoder(vox) pred = self.vox_fc(seq_emb) return pred class PositionalEncoding(nn.Module): def __init__(self, d_model, max_len=50): super(PositionalEncoding, self).__init__() pe = torch.zeros(max_len, d_model) # (max_len, d_model) position = torch.arange(0, max_len, dtype=torch.float).unsqueeze(1) # (max_len, 1) div_term = torch.exp(torch.arange(0, d_model, 2).float() * (-torch.log(torch.FloatTensor([10000.0])) / d_model)) # (d_model/2,) pe[:, 0::2] = torch.sin(position * div_term) # 偶数维 pe[:, 1::2] = torch.cos(position * div_term) # 奇数维 pe = pe.unsqueeze(0) # (1, max_len, d_model) self.register_buffer('pe', pe) def forward(self, x): """ x: (B, N, d_model) """ x = x + self.pe[:, :x.size(1), :] return x class TransformerModel(nn.Module): def __init__(self, nheads, d_model, num_layers, out_dim, max_length=50): super(TransformerModel, self).__init__() # 嵌入层,将输入从 (B, N) 转换到 (B, N, embed_dim) self.embedding = nn.Linear(1, d_model) # 位置编码 self.pos_encoder = PositionalEncoding(d_model, max_length) # Transformer 编码器层 encoder_layers = nn.TransformerEncoderLayer(d_model=d_model, nhead=nheads, activation='relu') self.transformer_encoder = nn.TransformerEncoder(encoder_layers, num_layers=num_layers) # 全局池化(可以根据任务选择不同的聚合方式) self.global_pool = nn.AdaptiveAvgPool1d(1) # 输出层 self.fc = nn.Linear(d_model, out_dim) def forward(self, src): """ src: (B, N) """ # 嵌入 embedded = self.embedding(src.unsqueeze(-1)) # (B, N, embed_dim) embedded = self.pos_encoder(embedded) # 添加位置编码 # 转置以适应 Transformer (N, B, embed_dim) embedded = embedded.permute(1, 0, 2) # Transformer 编码 transformer_out = self.transformer_encoder(embedded) # (N, B, embed_dim) # 转置回 (B, N, embed_dim) transformer_out = transformer_out.permute(1, 0, 2) # 全局池化,将 (B, N, embed_dim) 转换为 (B, embed_dim) pooled = self.global_pool(transformer_out.permute(0, 2, 1)).squeeze(-1) # 输出层 output = self.fc(pooled) # (B, output_dim) return output class MambaModel(nn.Module): def __init__(self, d_model, out_dim, max_length=30): super(MambaModel, self).__init__() self.linear = nn.Linear(in_features=1, out_features=d_model) self.pos_encoder = PositionalEncoding(d_model, max_length) self.mamba = Mamba(d_model=d_model) self.global_pool = nn.AdaptiveAvgPool1d(1) self.fc = nn.Linear(d_model * 2, out_dim) def forward(self, x: torch.Tensor): x = self.pos_encoder(self.linear(x.unsqueeze(-1))) y = self.mamba(x) y_flip = self.mamba(x.flip([-2])).flip([-2]) y = torch.cat((y, y_flip), dim=-1) y = self.fc(self.global_pool(y.permute(0, 2, 1)).squeeze(-1)) return y class SEQ(nn.Module): def __init__(self, seq_type='mlp', input_dim=21, hidden_dim=128, out_dim=128, num_layers=2, max_length=30): super(SEQ, self).__init__() self.seq_type = seq_type if seq_type == 'rnn': self.rnn = nn.RNN( input_size=input_dim, hidden_size=hidden_dim, num_layers=num_layers, batch_first=True, # input & output will take batch size as 1 dim (batch, time_step, input_size) bidirectional=True ) elif seq_type == 'gru': self.rnn = nn.GRU( input_size=input_dim, hidden_size=hidden_dim, num_layers=num_layers, batch_first=True, # input & output will take batch size as 1 dim (batch, time_step, input_size) bidirectional=True ) elif seq_type == 'lstm': self.rnn = nn.LSTM( input_size=input_dim, hidden_size=hidden_dim, num_layers=num_layers, batch_first=True, # input & output will take batch size as 1 dim (batch, time_step, input_size) bidirectional=True ) elif seq_type == 'tf': self.transformer = TransformerModel(nheads=4, d_model=hidden_dim, num_layers=2, out_dim=out_dim, max_length=max_length) elif seq_type == 'mamba': self.mamba = MambaModel(d_model=hidden_dim, out_dim=out_dim, max_length=max_length) else: # nn.Linear(50, 50, bias=False), nn.ReLU(), self.rnn = nn.Sequential(nn.Linear(max_length, hidden_dim * 4), nn.ReLU(), nn.Linear(hidden_dim * 4, out_dim)) self.rnn_fc = nn.Sequential( nn.Linear(hidden_dim * 2, hidden_dim), nn.ReLU(), nn.Linear(hidden_dim, out_dim) ) def forward(self, seq): if self.seq_type == 'mlp': return self.rnn(seq.squeeze(1)) elif self.seq_type == 'tf': return self.transformer(seq) elif self.seq_type == 'mamba': return self.mamba(seq) else: one_hot_seq = F.one_hot(seq.to(torch.int64), num_classes=21).float() r_out = self.rnn(one_hot_seq, None)[0] # None represents zero initial hidden state out = self.rnn_fc(r_out[:, -1, :]) return out # def forward(self, x, seq_lengths): # class SEQPeptide(nn.Module): def __init__(self, v_encoder='resnet26', q_encoder='mlp', fusion='mlp', classes=6, attention=None, max_length=30): super().__init__() self.classes = classes # q_encoder could be mlp, gru, rnn, lstm, transformer self.q_encoder = SEQ(seq_type=q_encoder, max_length=max_length) self.seq_fc = nn.Linear(128, classes) def forward(self, x, seq_lengths=None): vox, seq = x seq_emb = self.q_encoder(seq) pred = self.seq_fc(seq_emb) return pred class ConvNet(nn.Module): def __init__(self, num_classes: int = 2): super(ConvNet, self).__init__() self.conv1 = nn.Conv1d(3, 16, 3, padding=1) self.conv2 = nn.Conv1d(16, 32, 3, padding=1) self.fc1 = nn.Linear(32 * 7, 128) # self.fc2 = nn.Linear(128, num_classes) def forward(self, x): # print(x.shape) x = x.permute(0, 2, 1) x = F.relu(self.conv1(x)) x = F.max_pool1d(x, 2) x = F.relu(self.conv2(x)) x = F.max_pool1d(x, 2) x = x.view(x.shape[0], -1) return self.fc1(x) # x = F.relu(self.fc1(x)) # x = self.fc2(x) # return x class ConvNet2D(nn.Module): def __init__(self, num_classes: int = 2): super(ConvNet2D, self).__init__() self.conv1 = nn.Conv2d(1, 8, 3, padding=1) self.conv2 = nn.Conv2d(8, 16, 3, padding=2, stride=2) self.conv3 = nn.Conv2d(16, 32, 3, padding=2, stride=2) # self.pool = nn.AdaptiveAvgPool2d(32) self.fc1 = nn.Linear(32 * 3 * 9, 128) # self.fc2 = nn.Linear(128, num_classes) def forward(self, x): # print(x.shape) x = x.unsqueeze(1) x = F.relu(self.conv1(x)) # print(x.shape) x = F.relu(self.conv2(x)) # print(x.shape) x = F.relu(self.conv3(x)) # x = self.pool(x) # print(x.shape) x = x.view(x.shape[0], -1) return self.fc1(x) # convnet = ConvNet() # print(convnet) class MMPeptide(nn.Module): def __init__(self, v_encoder='resnet26', q_encoder='mlp', fusion='mlp', classes=6, attention=None, max_length=30): super().__init__() if attention == 'hamburger': self.attention = Hamburger(2048, 2048) else: self.attention = None # v_encoder could be resnet26 or resnet50 if v_encoder == 'resnet26': self.v_encoder = ResNet3D(Bottleneck3D, [1, 2, 4, 1], self.attention) # self.v_encoder = SwinUNETR(img_size=(64, 64, 64), in_channels=3, out_channels=1) elif v_encoder == 'resnet50': self.v_encoder = ResNet3D(Bottleneck3D, [3, 4, 6, 3], self.attention) else: raise NotImplementedError # q_encoder could be mlp, gru, rnn, lstm, transformer self.q_encoder = SEQ(seq_type=q_encoder, max_length=max_length) # self.ss_encoder = SEQ(seq_type=q_encoder) if fusion == 'mlp': self.fusion = nn.Linear(512 * 4 + 256, 256) # self.fusion = nn.Linear(192 + 256, classes) elif fusion == 'att': self.fusion = nn.Linear(512 * 4 + 256, 256) else: raise NotImplementedError # self.vox_fc = nn.Linear(2048, classes) # self.seq_fc = nn.Linear(256, classes) self.out = nn.Sequential(nn.ReLU(inplace=True), nn.Linear(256, classes)) self.classes = classes def forward(self, x, seq_lengths=None): vox, seq = x # print(vox.shape) # print(seq.shape) vox_emb = self.v_encoder(vox) # print(vox_emb.shape) seq_emb = self.q_encoder(seq, seq_lengths) # print(seq_emb.shape) # ss_emb = self.ss_encoder(second_s) fused_feature = torch.cat((seq_emb, vox_emb), dim=1) pred = self.fusion(fused_feature) pred = self.out(pred) # pred1 = self.vox_fc(vox_emb) # pred2 = self.seq_fc(seq_emb) # return pred, fused_feature return pred class SMPeptide(nn.Module): def __init__(self, v_encoder='resnet26', q_encoder='mlp', fusion='mlp', classes=6, attention=None, hidden_dim=256, max_length=30): super().__init__() self.siamese_encoder1 = MMPeptide(v_encoder, q_encoder, fusion, classes, attention, max_length) # self.siamese_encoder2 = MMPeptide(v_encoder, q_encoder, fusion, classes, attention) self.fc = nn.Sequential( nn.Linear(hidden_dim * 2, hidden_dim), nn.ReLU(), nn.Linear(hidden_dim, 1) ) def forward(self, x, seq_lengths=None): f_mutated = self.siamese_encoder1(x[0]) f_wide_type = self.siamese_encoder1(x[1]) return self.fc(torch.cat((f_mutated, f_wide_type), dim=1)) class MMFPeptide(nn.Module): def __init__(self, v_encoder='resnet26', q_encoder='mlp', fusion='mlp', classes=6, attention=None, max_length=30): super().__init__() if attention == 'hamburger': self.attention = Hamburger(2048, 2048) else: self.attention = None # v_encoder could be resnet26 or resnet50 if v_encoder == 'resnet26': self.v_encoder = ResNet3D(Bottleneck3D, [1, 2, 4, 1], self.attention) # self.v_encoder = ResNet3DFusion(Bottleneck, [1, 2, 4, 1], self.attention) elif v_encoder == 'resnet50': self.v_encoder = ResNet3D(Bottleneck3D, [3, 4, 6, 3], self.attention) else: raise NotImplementedError # q_encoder could be mlp, gru, rnn, lstm, transformer self.q_encoder = SEQ(seq_type=q_encoder, max_length=max_length) if fusion == 'mlp': self.fusion = nn.Linear(512 * 4 + 256, classes) elif fusion == 'att': self.fusion = nn.Linear(512 * 4 + 256, classes) else: raise NotImplementedError self.vox_fc = nn.Linear(2048, classes) self.seq_fc = nn.Linear(256, classes) def forward(self, x, seq_lengths=None): vox, seq = x # print(vox.shape) # print(seq.shape) seq_emb = self.q_encoder(seq, seq_lengths) vox_emb = self.v_encoder(vox, seq_emb) # print(vox_emb.shape) # print(seq_emb.shape) fused_feature = torch.cat((seq_emb, vox_emb), dim=1) pred = self.fusion(fused_feature) # pred1 = self.vox_fc(vox_emb) # pred2 = self.seq_fc(seq_emb) return pred if __name__ == "__main__": # model = MMFPeptide() # voxel = torch.zeros((4, 3, 64, 64, 64)) # # # h_in = torch.zeros((2, 2048, 2, 2, 2)) # # # h = Hamburger(2048, 2048) # # # h(h_in) # seq = torch.ones((4, 50)) # res = model.forward((voxel, seq)) # out = model((voxel, seq)) # print(out.shape) # model = ConvNet2D() input_seq = torch.ones((4, 1, 30)) # model(input_seq) transformer = TransformerModel(nhead=4, d_model=32, num_layers=2) print(transformer(input_seq).shape)