diff --git a/models/modeling.py b/models/modeling.py index fc3082b..ea5b1ae 100755 --- a/models/modeling.py +++ b/models/modeling.py @@ -22,26 +22,35 @@ import models.configs as configs logger = logging.getLogger(__name__) +#多头注意力参数 ATTENTION_Q = "MultiHeadDotProductAttention_1/query" ATTENTION_K = "MultiHeadDotProductAttention_1/key" ATTENTION_V = "MultiHeadDotProductAttention_1/value" ATTENTION_OUT = "MultiHeadDotProductAttention_1/out" + +#Dense全连接层 FC_0 = "MlpBlock_3/Dense_0" FC_1 = "MlpBlock_3/Dense_1" + +#批归一化曾 ATTENTION_NORM = "LayerNorm_0" MLP_NORM = "LayerNorm_2" +#numpy转tensor def np2th(weights, conv=False): """Possibly convert HWIO to OIHW.""" if conv: weights = weights.transpose([3, 2, 0, 1]) return torch.from_numpy(weights) +#swish激活函数 def swish(x): return x * torch.sigmoid(x) +#gelu激活函数 ACT2FN = {"gelu": torch.nn.functional.gelu, "relu": torch.nn.functional.relu, "swish": swish} +#标签平滑类,用于数据增强 class LabelSmoothing(nn.Module): """ NLL loss with label smoothing. @@ -64,6 +73,7 @@ class LabelSmoothing(nn.Module): loss = self.confidence * nll_loss + self.smoothing * smooth_loss return loss.mean() +#注意力层 class Attention(nn.Module): def __init__(self, config): super(Attention, self).__init__() @@ -109,6 +119,7 @@ class Attention(nn.Module): attention_output = self.proj_dropout(attention_output) return attention_output, weights +#全连接层 class Mlp(nn.Module): def __init__(self, config): super(Mlp, self).__init__() @@ -133,6 +144,7 @@ class Mlp(nn.Module): x = self.dropout(x) return x +#嵌入编码 class Embeddings(nn.Module): """Construct the embeddings from patch, position embeddings. """ @@ -174,6 +186,7 @@ class Embeddings(nn.Module): embeddings = self.dropout(embeddings) return embeddings +#块 class Block(nn.Module): def __init__(self, config): super(Block, self).__init__() @@ -232,7 +245,7 @@ class Block(nn.Module): self.ffn_norm.weight.copy_(np2th(weights[pjoin(ROOT, MLP_NORM, "scale")])) self.ffn_norm.bias.copy_(np2th(weights[pjoin(ROOT, MLP_NORM, "bias")])) - +#部分注意力层 class Part_Attention(nn.Module): def __init__(self): super(Part_Attention, self).__init__() @@ -247,7 +260,7 @@ class Part_Attention(nn.Module): _, max_inx = last_map.max(2) return _, max_inx - +#编码器 class Encoder(nn.Module): def __init__(self, config): super(Encoder, self).__init__() @@ -277,7 +290,7 @@ class Encoder(nn.Module): return part_encoded - +#Transformer层 class Transformer(nn.Module): def __init__(self, config, img_size): super(Transformer, self).__init__() @@ -289,7 +302,85 @@ class Transformer(nn.Module): part_encoded = self.encoder(embedding_output) return part_encoded +#VIT层 +class OldVisionTransformer(nn.Module): + def __init__(self, config, img_size=224, num_classes=21843, zero_head=False, vis=False): + super(VisionTransformer, self).__init__() + self.num_classes = num_classes + self.zero_head = zero_head + self.classifier = config.classifier + self.transformer = Transformer(config, img_size, vis) + self.head = Linear(config.hidden_size, num_classes) + + def forward(self, x, labels=None): + x, attn_weights = self.transformer(x) + logits = self.head(x[:, 0]) + + if labels is not None: + loss_fct = CrossEntropyLoss() + loss = loss_fct(logits.view(-1, self.num_classes), labels.view(-1)) + return loss + else: + return logits, attn_weights + + def load_from(self, weights): + with torch.no_grad(): + if self.zero_head: + nn.init.zeros_(self.head.weight) + nn.init.zeros_(self.head.bias) + else: + self.head.weight.copy_(np2th(weights["head/kernel"]).t()) + self.head.bias.copy_(np2th(weights["head/bias"]).t()) + + self.transformer.embeddings.patch_embeddings.weight.copy_(np2th(weights["embedding/kernel"], conv=True)) + self.transformer.embeddings.patch_embeddings.bias.copy_(np2th(weights["embedding/bias"])) + self.transformer.embeddings.cls_token.copy_(np2th(weights["cls"])) + self.transformer.encoder.encoder_norm.weight.copy_(np2th(weights["Transformer/encoder_norm/scale"])) + self.transformer.encoder.encoder_norm.bias.copy_(np2th(weights["Transformer/encoder_norm/bias"])) + + posemb = np2th(weights["Transformer/posembed_input/pos_embedding"]) + posemb_new = self.transformer.embeddings.position_embeddings + if posemb.size() == posemb_new.size(): + self.transformer.embeddings.position_embeddings.copy_(posemb) + else: + print("load_pretrained: resized variant: %s to %s" % (posemb.size(), posemb_new.size())) + ntok_new = posemb_new.size(1) + + if self.classifier == "token": + posemb_tok, posemb_grid = posemb[:, :1], posemb[0, 1:] + ntok_new -= 1 + else: + posemb_tok, posemb_grid = posemb[:, :0], posemb[0] + + gs_old = int(np.sqrt(len(posemb_grid))) + gs_new = int(np.sqrt(ntok_new)) + print('load_pretrained: grid-size from %s to %s' % (gs_old, gs_new)) + posemb_grid = posemb_grid.reshape(gs_old, gs_old, -1) + + zoom = (gs_new / gs_old, gs_new / gs_old, 1) + posemb_grid = ndimage.zoom(posemb_grid, zoom, order=1) + posemb_grid = posemb_grid.reshape(1, gs_new * gs_new, -1) + posemb = np.concatenate([posemb_tok, posemb_grid], axis=1) + self.transformer.embeddings.position_embeddings.copy_(np2th(posemb)) + + for bname, block in self.transformer.encoder.named_children(): + for uname, unit in block.named_children(): + unit.load_from(weights, n_block=uname) + + if self.transformer.embeddings.hybrid: + self.transformer.embeddings.hybrid_model.root.conv.weight.copy_(np2th(weights["conv_root/kernel"], conv=True)) + gn_weight = np2th(weights["gn_root/scale"]).view(-1) + gn_bias = np2th(weights["gn_root/bias"]).view(-1) + self.transformer.embeddings.hybrid_model.root.gn.weight.copy_(gn_weight) + self.transformer.embeddings.hybrid_model.root.gn.bias.copy_(gn_bias) + + for bname, block in self.transformer.embeddings.hybrid_model.body.named_children(): + for uname, unit in block.named_children(): + unit.load_from(weights, n_block=bname, n_unit=uname) + + +#VIT FG层 class VisionTransformer(nn.Module): def __init__(self, config, img_size=224, num_classes=21843, smoothing_value=0, zero_head=False): super(VisionTransformer, self).__init__() @@ -302,7 +393,7 @@ class VisionTransformer(nn.Module): def forward(self, x, labels=None): part_tokens = self.transformer(x) - part_logits = self.part_head(part_tokens[:, 0]) + part_logits = self.part_head(part_tokens[:, 0]) #part部分可以理解是细粒度,它专注于捕捉微小差异。但生物其实不需要这个,因为生物视觉本身就是有part功能的,通过眼球转动调整感受野来完成这一点 if labels is not None: if self.smoothing_value == 0: @@ -365,7 +456,7 @@ class VisionTransformer(nn.Module): for uname, unit in block.named_children(): unit.load_from(weights, n_block=bname, n_unit=uname) - +#loss计算 def con_loss(features, labels): B, _ = features.shape features = F.normalize(features) @@ -379,7 +470,7 @@ def con_loss(features, labels): loss /= (B * B) return loss - +#几种VIT模型配置 CONFIGS = { 'ViT-B_16': configs.get_b16_config(), 'ViT-B_32': configs.get_b32_config(),