模型：# 将 4输入分开，构建新的相同模态结合的2输入，2分支
import math
import logging
from functools import partial
from collections import OrderedDict
from copy import deepcopy

import torch
import torch.nn as nn
import torch.nn.functional as F

from timm.models.layers import to_2tuple

from lib.models.layers.patch_embed import PatchEmbed, PatchEmbed_event, xcorr_depthwise
from .utils import combine_tokens, recover_tokens
from .vit import VisionTransformer
from ..layers.attn_blocks import CEBlock

_logger = logging.getLogger(__name__)
                            

class VisionTransformerCE(VisionTransformer):
    """ Vision Transformer with candidate elimination (CE) module

    A PyTorch impl of : `An Image is Worth 16x16 Words: Transformers for Image Recognition at Scale`
        - https://arxiv.org/abs/2010.11929

    Includes distillation token & head support for `DeiT: Data-efficient Image Transformers`
        - https://arxiv.org/abs/2012.12877
    """
    def __init__(self, img_size=224, patch_size=16, in_chans=3, num_classes=1000, embed_dim=768, depth=12,
                 num_heads=12, mlp_ratio=4., qkv_bias=True, representation_size=None, distilled=False,
                 drop_rate=0., attn_drop_rate=0., drop_path_rate=0., embed_layer=PatchEmbed, norm_layer=None,
                 act_layer=None, weight_init='',
                 ce_loc=None, ce_keep_ratio=None):
        super().__init__()
        if isinstance(img_size, tuple):
            self.img_size = img_size
        else:
            self.img_size = to_2tuple(img_size)
        self.patch_size = patch_size
        self.in_chans = in_chans

        self.num_classes = num_classes
        self.num_features = self.embed_dim = embed_dim  # num_features for consistency with other models
        self.num_tokens = 2 if distilled else 1
        norm_layer = norm_layer or partial(nn.LayerNorm, eps=1e-6)
        act_layer = act_layer or nn.GELU

        self.patch_embed = embed_layer(
            img_size=img_size, patch_size=patch_size, in_chans=in_chans, embed_dim=embed_dim)
        num_patches = self.patch_embed.num_patches

        self.cls_token = nn.Parameter(torch.zeros(1, 1, embed_dim))
        self.dist_token = nn.Parameter(torch.zeros(1, 1, embed_dim)) if distilled else None
        self.pos_embed = nn.Parameter(torch.zeros(1, num_patches + self.num_tokens, embed_dim))
        self.pos_drop = nn.Dropout(p=drop_rate)
        self.pos_embed_event = PatchEmbed_event(in_chans=32, embed_dim=768, kernel_size=4, stride=4)
        dpr = [x.item() for x in torch.linspace(0, drop_path_rate, depth)]  # stochastic depth decay rule
        blocks = []
        ce_index = 0
        self.ce_loc = ce_loc
        for i in range(depth):
            ce_keep_ratio_i = 1.0
            if ce_loc is not None and i in ce_loc:
                ce_keep_ratio_i = ce_keep_ratio[ce_index]
                ce_index += 1

            blocks.append(
                CEBlock(
                    dim=embed_dim, num_heads=num_heads, mlp_ratio=mlp_ratio, qkv_bias=qkv_bias, drop=drop_rate,
                    attn_drop=attn_drop_rate, drop_path=dpr[i], norm_layer=norm_layer, act_layer=act_layer,
                    keep_ratio_search=ce_keep_ratio_i)
            )

        self.blocks = nn.Sequential(*blocks)
        self.norm = norm_layer(embed_dim)

        self.init_weights(weight_init)
        # New event processing layers initialization:
        self.phi_1x1_event_3 = nn.Conv2d(3, embed_dim, kernel_size=1)
        self.phi_1x1_event = nn.Conv2d(embed_dim, embed_dim, kernel_size=1)
        self.max_pool_event = nn.MaxPool2d(kernel_size=2, stride=2)
        self.avg_pool_event = nn.AvgPool2d(kernel_size=2, stride=2)
        self.phi_1x1_stage2_event = nn.Conv2d(embed_dim, embed_dim, kernel_size=1)
        
        self.phi_2x2_event = nn.Conv2d(embed_dim, embed_dim, kernel_size=1)
        self.pool_3 = nn.MaxPool2d(kernel_size=3, stride=2, padding=1)
        self.pool_5 = nn.MaxPool2d(kernel_size=5, stride=2, padding=2)
        self.pool_7 = nn.MaxPool2d(kernel_size=7, stride=2, padding=3)
        self.pool_9 = nn.MaxPool2d(kernel_size=9, stride=2, padding=4)

    
    
    def forward_features(self, z, x, event_z, event_x,
                         mask_z=None, mask_x=None,
                         ce_template_mask=None, ce_keep_rate=None,
                         return_last_attn=False
                         ):
        # 分支1 处理流程
        B, H, W = x.shape[0], x.shape[2], x.shape[3]

        x = self.patch_embed(x)
        z = self.patch_embed(z)
        z += self.pos_embed_z
        x += self.pos_embed_x        

        if mask_z is not None and mask_x is not None:
            mask_z = F.interpolate(mask_z[None].float(), scale_factor=1. / self.patch_size).to(torch.bool)[0]
            mask_z = mask_z.flatten(1).unsqueeze(-1)

            mask_x = F.interpolate(mask_x[None].float(), scale_factor=1. / self.patch_size).to(torch.bool)[0]
            mask_x = mask_x.flatten(1).unsqueeze(-1)

            mask_x = combine_tokens(mask_z, mask_x, mode=self.cat_mode)
            mask_x = mask_x.squeeze(-1)

        if self.add_cls_token:
            cls_tokens = self.cls_token.expand(B, -1, -1)
            cls_tokens = cls_tokens + self.cls_pos_embed
        if self.add_sep_seg:
            x += self.search_segment_pos_embed
            z += self.template_segment_pos_embed
        x = combine_tokens(z, x, mode=self.cat_mode)
        if self.add_cls_token:
            x = torch.cat([cls_tokens, x], dim=1)
        x = self.pos_drop(x)

        lens_z = self.pos_embed_z.shape[1]
        lens_x = self.pos_embed_x.shape[1]
        global_index_t = torch.linspace(0, lens_z - 1, lens_z).to(x.device)
        global_index_t = global_index_t.repeat(B, 1)
        global_index_s = torch.linspace(0, lens_x - 1, lens_x).to(x.device)
        global_index_s = global_index_s.repeat(B, 1)
        removed_indexes_s = []

        for i, blk in enumerate(self.blocks):
            x, global_index_t, global_index_s, removed_index_s, attn = \
                blk(x, global_index_t, global_index_s, mask_x, ce_template_mask, ce_keep_rate)


            if self.ce_loc is not None and i in self.ce_loc:
                removed_indexes_s.append(removed_index_s)
        x = self.norm(x) # # [bs, n_patch, dim] = [bs, 320, 768] 320 = 64 + 256
       

        # # 分支2 处理流程
        # event_x = self.pos_embed_event(event_x)
        # event_z = self.pos_embed_event(event_z)
        # event_x += self.pos_embed_x
        # event_z += self.pos_embed_z

        # event_x = combine_tokens(event_z, event_x, mode=self.cat_mode)

        # if self.add_cls_token:
        #     event_x = torch.cat([cls_tokens, event_x], dim=1)

        # lens_z = self.pos_embed_z.shape[1]
        # lens_x = self.pos_embed_x.shape[1]

        # global_index_t1 = torch.linspace(0, lens_z - 1, lens_z).to(event_x.device)
        # global_index_t1 = global_index_t1.repeat(B, 1)
        # global_index_s1 = torch.linspace(0, lens_x - 1, lens_x).to(event_x.device)
        # global_index_s1 = global_index_s1.repeat(B, 1)

        # removed_indexes_s1 = []
        # for i, blk in enumerate(self.blocks):
        #     event_x, global_index_t1, global_index_s1, removed_index_s1, attn = \
        #         blk(event_x, global_index_t1, global_index_s1, mask_x, ce_template_mask, ce_keep_rate)

        #     if self.ce_loc is not None and i in self.ce_loc:
        #         removed_indexes_s1.append(removed_index_s1)
        # event_x = self.norm(event_x)

        ########################
        # Process event features:
        print('event_x.shape: ',event_x.shape)  # event_x.shape:  torch.Size([2, 3, 256, 256])
        event_x = self.phi_1x1_event_3(event_x)
        print('1_1_event_x.shape: ',event_x.shape) # 
        FEf_event = self.max_pool_event(event_x)
        FEi_event = self.max_pool_event(self.phi_1x1_event(FEf_event))
        FEj_event = self.avg_pool_event(self.phi_1x1_event(FEf_event))
        FE1_event = FEi_event + FEj_event

        FEi = self.phi_2x2_event(FE1_event)
        event_splits = torch.chunk(FEi, 4, dim=1)
        
        A = self.pool_3(event_splits[0])
        B = self.pool_5(event_splits[1])
        BC = self.pool_7(torch.cat([B, event_splits[2]], dim=1))
        BCD = self.pool_9(torch.cat([BC, event_splits[3]], dim=1))
        
        FE2_event = torch.cat([A, B, BC, BCD], dim=1)
        FE2_event = self.phi_1x1_stage2_event(FE2_event)
        FE_final_event = torch.cat([FE1_event, FE2_event], dim=1)
        event_x = self.norm(FE_final_event)
        print('Pool_event_x.shape: ',event_x.shape) 
        #########################
        # print('x.shape: ',x.shape) #x.shape:  torch.Size([2, 320, 768])
        # print('event_x.shape: ',event_x.shape) # event_x.shape:  torch.Size([2, 320, 768])
        x_cat = torch.cat([x, event_x], dim=1) 
        # print('x_cat.shape: ',x_cat.shape) # x_cat.shape:  torch.Size([2, 640, 768])
        x = x_cat

        aux_dict = {
            "attn": attn,
            "removed_indexes_s": removed_indexes_s,  # used for visualization
        }
        
        return x, aux_dict 

    def forward(self, z, x, event_z, event_x,
                ce_template_mask=None, ce_keep_rate=None,
                tnc_keep_rate=None,
                return_last_attn=False):

        x, aux_dict = self.forward_features(z, x, event_z, event_x, ce_template_mask=ce_template_mask, ce_keep_rate=ce_keep_rate,)

        return x, aux_dict


def _create_vision_transformer(pretrained=False, **kwargs):
    model = VisionTransformerCE(**kwargs)
    
    if pretrained:
        if 'npz' in pretrained:
            model.load_pretrained(pretrained, prefix='')
        else:
            checkpoint = torch.load(pretrained, map_location="cpu")
            missing_keys, unexpected_keys = model.load_state_dict(checkpoint["model"], strict=False)
            print('Load pretrained model from: ' + pretrained)

    return model


def vit_base_patch16_224_ce(pretrained=False, **kwargs):
    """ ViT-Base model (ViT-B/16) from original paper (https://arxiv.org/abs/2010.11929).
    """
    model_kwargs = dict(
        patch_size=16, embed_dim=768, depth=12, num_heads=12, **kwargs)
    model = _create_vision_transformer(pretrained=pretrained, **model_kwargs)
    return model


def vit_large_patch16_224_ce(pretrained=False, **kwargs):
    """ ViT-Large model (ViT-L/16) from original paper (https://arxiv.org/abs/2010.11929).
    """
    model_kwargs = dict(
        patch_size=16, embed_dim=1024, depth=24, num_heads=16, **kwargs)
    model = _create_vision_transformer(pretrained=pretrained, **model_kwargs)
    return model 中，运行报错：event_x.shape:  torch.Size([2, 3, 256, 256])
1_1_event_x.shape:  torch.Size([2, 768, 256, 256])
Training crashed at epoch 1
Traceback for the error!
Traceback (most recent call last):
  File "/data2/local_userdata/heyuting/new_VOT/COESOT-main/CEUTrack/lib/train/../../lib/train/trainers/base_trainer.py", line 85, in train
    self.train_epoch()
  File "/data2/local_userdata/heyuting/new_VOT/COESOT-main/CEUTrack/lib/train/../../lib/train/trainers/ltr_trainer.py", line 133, in train_epoch
    self.cycle_dataset(loader)
  File "/data2/local_userdata/heyuting/new_VOT/COESOT-main/CEUTrack/lib/train/../../lib/train/trainers/ltr_trainer.py", line 86, in cycle_dataset
    loss, stats = self.actor(data)
  File "/data2/local_userdata/heyuting/new_VOT/COESOT-main/CEUTrack/lib/train/../../lib/train/actors/ceutrack.py", line 285, in __call__
    out_dict = self.forward_pass(data)
  File "/data2/local_userdata/heyuting/new_VOT/COESOT-main/CEUTrack/lib/train/../../lib/train/actors/ceutrack.py", line 334, in forward_pass
    return_last_attn=False)
  File "/home/heyuting/anaconda3/envs/ceu/lib/python3.7/site-packages/torch/nn/modules/module.py", line 1130, in _call_impl
    return forward_call(*input, **kwargs)
  File "/data2/local_userdata/heyuting/new_VOT/COESOT-main/CEUTrack/lib/train/../../lib/models/ceutrack/ceutrack.py", line 54, in forward
    return_last_attn=return_last_attn)
  File "/home/heyuting/anaconda3/envs/ceu/lib/python3.7/site-packages/torch/nn/modules/module.py", line 1130, in _call_impl
    return forward_call(*input, **kwargs)
  File "/data2/local_userdata/heyuting/new_VOT/COESOT-main/CEUTrack/lib/train/../../lib/models/ceutrack/vit_ce.py", line 217, in forward
    x, aux_dict = self.forward_features(z, x, event_z, event_x, ce_template_mask=ce_template_mask, ce_keep_rate=ce_keep_rate,)
  File "/data2/local_userdata/heyuting/new_VOT/COESOT-main/CEUTrack/lib/train/../../lib/models/ceutrack/vit_ce.py", line 190, in forward_features
    BC = self.pool_7(torch.cat([B, event_splits[2]], dim=1))
RuntimeError: Sizes of tensors must match except in dimension 1. Expected size 32 but got size 64 for tensor number 1 in the list.

Restarting training from last epoch ...
Finished training!