import torch import torch.nn as nn from torch.nn import BCEWithLogitsLoss,CrossEntropyLoss, Dropout, Softmax, Linear, Conv2d, LayerNorm import models.configs as configs import math class Attention(nn.Module): def __init__(self, config, vis, mm=True): super(Attention, self).__init__() self.vis = vis self.num_attention_heads = config.transformer["num_heads"] self.attention_head_size = int(config.hidden_size / self.num_attention_heads) self.all_head_size = self.num_attention_heads * self.attention_head_size self.query = Linear(config.hidden_size, self.all_head_size) self.key = Linear(config.hidden_size, self.all_head_size) self.value = Linear(config.hidden_size, self.all_head_size) if mm: self.query_text = Linear(config.hidden_size, self.all_head_size) self.key_text = Linear(config.hidden_size, self.all_head_size) self.value_text = Linear(config.hidden_size, self.all_head_size) self.out_text = Linear(config.hidden_size, config.hidden_size) self.attn_dropout_text = Dropout(config.transformer["attention_dropout_rate"]) self.attn_dropout_it = Dropout(config.transformer["attention_dropout_rate"]) self.attn_dropout_ti = Dropout(config.transformer["attention_dropout_rate"]) self.proj_dropout_text = Dropout(config.transformer["attention_dropout_rate"]) self.out = Linear(config.hidden_size, config.hidden_size) self.attn_dropout = Dropout(config.transformer["attention_dropout_rate"]) self.proj_dropout = Dropout(config.transformer["attention_dropout_rate"]) self.softmax = Softmax(dim=-1) def transpose_for_scores(self, x): new_x_shape = x.size()[:-1] + (self.num_attention_heads, self.attention_head_size) x = x.view(*new_x_shape) return x.permute(0, 2, 1, 3) def forward(self, hidden_states, text=None): mixed_query_layer = self.query(hidden_states) mixed_key_layer = self.key(hidden_states) mixed_value_layer = self.value(hidden_states) if text is not None: text_q = self.query_text(text) text_k = self.key_text(text) text_v = self.value_text(text) query_layer = self.transpose_for_scores(mixed_query_layer) key_layer = self.transpose_for_scores(mixed_key_layer) value_layer = self.transpose_for_scores(mixed_value_layer) if text is not None: query_layer_img = query_layer key_layer_img = key_layer value_layer_img = value_layer query_layer_text = self.transpose_for_scores(text_q) key_layer_text = self.transpose_for_scores(text_k) value_layer_text = self.transpose_for_scores(text_v) if text is None: attention_scores = torch.matmul(query_layer, key_layer.transpose(-1, -2)) attention_scores = attention_scores / math.sqrt(self.attention_head_size) attention_probs = self.softmax(attention_scores) weights = attention_probs if self.vis else None attention_probs = self.attn_dropout(attention_probs) context_layer = torch.matmul(attention_probs, value_layer) context_layer = context_layer.permute(0, 2, 1, 3).contiguous() new_context_layer_shape = context_layer.size()[:-2] + (self.all_head_size,) context_layer = context_layer.view(*new_context_layer_shape) attention_output = self.out(context_layer) attention_output = self.proj_dropout(attention_output) return attention_output,None, weights else: attention_scores_img = torch.matmul(query_layer, key_layer.transpose(-1, -2)) attention_scores_text = torch.matmul(query_layer_text, key_layer_text.transpose(-1, -2)) attention_scores_it = torch.matmul(query_layer_img, key_layer_text.transpose(-1, -2)) attention_scores_ti = torch.matmul(query_layer_text, key_layer_img.transpose(-1, -2)) attention_scores_img = attention_scores_img / math.sqrt(self.attention_head_size) attention_probs_img = self.softmax(attention_scores_img) weights_img = attention_probs_img if self.vis else None attention_probs_img = self.attn_dropout(attention_probs_img) attention_scores_text = attention_scores_text / math.sqrt(self.attention_head_size) attention_probs_text = self.softmax(attention_scores_text) text_per_weights = attention_probs_text.mean(dim=-1) text_per_weights = self.softmax(text_per_weights) weights_text = attention_probs_text if self.vis else None attention_probs_text = self.attn_dropout_text(attention_probs_text) attention_scores_it = attention_scores_it / math.sqrt(self.attention_head_size) attention_probs_it = self.softmax(attention_scores_it) attention_probs_it = self.attn_dropout_it(attention_probs_it) attention_scores_ti = attention_scores_ti / math.sqrt(self.attention_head_size) attention_probs_ti = self.softmax(attention_scores_ti) attention_probs_ti = self.attn_dropout_ti(attention_probs_ti) context_layer_img = torch.matmul(attention_probs_img, value_layer_img) context_layer_img = context_layer_img.permute(0, 2, 1, 3).contiguous() context_layer_text = torch.matmul(attention_probs_text, value_layer_text) context_layer_text = context_layer_text.permute(0, 2, 1, 3).contiguous() context_layer_it = torch.matmul(attention_probs_it, value_layer_text) context_layer_it = context_layer_it.permute(0, 2, 1, 3).contiguous() context_layer_ti = torch.matmul(attention_probs_ti, value_layer_img) context_layer_ti = context_layer_ti.permute(0, 2, 1, 3).contiguous() new_context_layer_shape = context_layer_img.size()[:-2] + (self.all_head_size,) context_layer_img = context_layer_img.view(*new_context_layer_shape) new_context_layer_shape = context_layer_text.size()[:-2] + (self.all_head_size,) context_layer_text = context_layer_text.view(*new_context_layer_shape) new_context_layer_shape = context_layer_it.size()[:-2] + (self.all_head_size,) context_layer_it = context_layer_it.view(*new_context_layer_shape) new_context_layer_shape = context_layer_ti.size()[:-2] + (self.all_head_size,) context_layer_ti = context_layer_ti.view(*new_context_layer_shape) attention_output_img = self.out((context_layer_img + context_layer_it)/2) attention_output_text = self.out((context_layer_text + context_layer_ti)/2) attention_output_img = self.proj_dropout(attention_output_img) attention_output_text = self.proj_dropout_text(attention_output_text) return attention_output_img, attention_output_text