① MambaIR：# Code Implementation of the MambaIR Model
import warnings
warnings.filterwarnings("ignore")
import math
import torch
import torch.nn as nn
import torch.nn.functional as F
from functools import partial
from typing import Optional, Callable
from timm.models.layers import DropPath, to_2tuple, trunc_normal_
from mamba_ssm.ops.selective_scan_interface import selective_scan_fn, selective_scan_ref
from einops import rearrange, repeat


"""
最近，选择性结构化状态空间模型，特别是改进版本的Mamba，在线性复杂度的远程依赖建模方面表现出了巨大的潜力。
然而，标准Mamba在低级视觉方面仍然面临一定的挑战，例如局部像素遗忘和通道冗余。在这项工作中，我们引入了局部增强和通道注意力来改进普通 Mamba。
通过这种方式，我们利用了局部像素相似性并减少了通道冗余。大量的实验证明了我们方法的优越性。
"""


NEG_INF = -1000000


class ChannelAttention(nn.Module):
    """Channel attention used in RCAN.
    Args:
        num_feat (int): Channel number of intermediate features.
        squeeze_factor (int): Channel squeeze factor. Default: 16.
    """

    def __init__(self, num_feat, squeeze_factor=16):
        super(ChannelAttention, self).__init__()
        self.attention = nn.Sequential(
            nn.AdaptiveAvgPool2d(1),
            nn.Conv2d(num_feat, num_feat // squeeze_factor, 1, padding=0),
            nn.ReLU(inplace=True),
            nn.Conv2d(num_feat // squeeze_factor, num_feat, 1, padding=0),
            nn.Sigmoid())

    def forward(self, x):
        y = self.attention(x)
        return x * y


class CAB(nn.Module):
    def __init__(self, num_feat, is_light_sr= False, compress_ratio=3,squeeze_factor=30):
        super(CAB, self).__init__()
        if is_light_sr: # we use depth-wise conv for light-SR to achieve more efficient
            self.cab = nn.Sequential(
                nn.Conv2d(num_feat, num_feat, 3, 1, 1, groups=num_feat),
                ChannelAttention(num_feat, squeeze_factor)
            )
        else: # for classic SR
            self.cab = nn.Sequential(
                nn.Conv2d(num_feat, num_feat // compress_ratio, 3, 1, 1),
                nn.GELU(),
                nn.Conv2d(num_feat // compress_ratio, num_feat, 3, 1, 1),
                ChannelAttention(num_feat, squeeze_factor)
            )

    def forward(self, x):
        return self.cab(x)


class Mlp(nn.Module):
    def __init__(self, in_features, hidden_features=None, out_features=None, act_layer=nn.GELU, drop=0.):
        super().__init__()
        out_features = out_features or in_features
        hidden_features = hidden_features or in_features
        self.fc1 = nn.Linear(in_features, hidden_features)
        self.act = act_layer()
        self.fc2 = nn.Linear(hidden_features, out_features)
        self.drop = nn.Dropout(drop)

    def forward(self, x):
        x = self.fc1(x)
        x = self.act(x)
        x = self.drop(x)
        x = self.fc2(x)
        x = self.drop(x)
        return x


class DynamicPosBias(nn.Module):
    def __init__(self, dim, num_heads):
        super().__init__()
        self.num_heads = num_heads
        self.pos_dim = dim // 4
        self.pos_proj = nn.Linear(2, self.pos_dim)
        self.pos1 = nn.Sequential(
            nn.LayerNorm(self.pos_dim),
            nn.ReLU(inplace=True),
            nn.Linear(self.pos_dim, self.pos_dim),
        )
        self.pos2 = nn.Sequential(
            nn.LayerNorm(self.pos_dim),
            nn.ReLU(inplace=True),
            nn.Linear(self.pos_dim, self.pos_dim)
        )
        self.pos3 = nn.Sequential(
            nn.LayerNorm(self.pos_dim),
            nn.ReLU(inplace=True),
            nn.Linear(self.pos_dim, self.num_heads)
        )

    def forward(self, biases):
        pos = self.pos3(self.pos2(self.pos1(self.pos_proj(biases))))
        return pos

    def flops(self, N):
        flops = N * 2 * self.pos_dim
        flops += N * self.pos_dim * self.pos_dim
        flops += N * self.pos_dim * self.pos_dim
        flops += N * self.pos_dim * self.num_heads
        return flops


class Attention(nn.Module):
    r""" Multi-head self attention module with dynamic position bias.

    Args:
        dim (int): Number of input channels.
        num_heads (int): Number of attention heads.
        qkv_bias (bool, optional):  If True, add a learnable bias to query, key, value. Default: True
        qk_scale (float | None, optional): Override default qk scale of head_dim ** -0.5 if set
        attn_drop (float, optional): Dropout ratio of attention weight. Default: 0.0
        proj_drop (float, optional): Dropout ratio of output. Default: 0.0
    """

    def __init__(self, dim, num_heads, qkv_bias=True, qk_scale=None, attn_drop=0., proj_drop=0.,
                 position_bias=True):

        super().__init__()
        self.dim = dim
        self.num_heads = num_heads
        head_dim = dim // num_heads
        self.scale = qk_scale or head_dim ** -0.5
        self.position_bias = position_bias
        if self.position_bias:
            self.pos = DynamicPosBias(self.dim // 4, self.num_heads)

        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)

        self.softmax = nn.Softmax(dim=-1)

    def forward(self, x, H, W, mask=None):
        """
        Args:
            x: input features with shape of (num_groups*B, N, C)
            mask: (0/-inf) mask with shape of (num_groups, Gh*Gw, Gh*Gw) or None
            H: height of each group
            W: width of each group
        """
        group_size = (H, W)
        B_, N, C = x.shape
        assert H * W == N
        qkv = self.qkv(x).reshape(B_, N, 3, self.num_heads, C // self.num_heads).permute(2, 0, 3, 1, 4).contiguous()
        q, k, v = qkv[0], qkv[1], qkv[2]

        q = q * self.scale
        attn = (q @ k.transpose(-2, -1))  # (B_, self.num_heads, N, N), N = H*W

        if self.position_bias:
            # generate mother-set
            position_bias_h = torch.arange(1 - group_size[0], group_size[0], device=attn.device)
            position_bias_w = torch.arange(1 - group_size[1], group_size[1], device=attn.device)
            biases = torch.stack(torch.meshgrid([position_bias_h, position_bias_w]))  # 2, 2Gh-1, 2W2-1
            biases = biases.flatten(1).transpose(0, 1).contiguous().float()  # (2h-1)*(2w-1) 2

            # get pair-wise relative position index for each token inside the window
            coords_h = torch.arange(group_size[0], device=attn.device)
            coords_w = torch.arange(group_size[1], device=attn.device)
            coords = torch.stack(torch.meshgrid([coords_h, coords_w]))  # 2, Gh, Gw
            coords_flatten = torch.flatten(coords, 1)  # 2, Gh*Gw
            relative_coords = coords_flatten[:, :, None] - coords_flatten[:, None, :]  # 2, Gh*Gw, Gh*Gw
            relative_coords = relative_coords.permute(1, 2, 0).contiguous()  # Gh*Gw, Gh*Gw, 2
            relative_coords[:, :, 0] += group_size[0] - 1  # shift to start from 0
            relative_coords[:, :, 1] += group_size[1] - 1
            relative_coords[:, :, 0] *= 2 * group_size[1] - 1
            relative_position_index = relative_coords.sum(-1)  # Gh*Gw, Gh*Gw

            pos = self.pos(biases)  # 2Gh-1 * 2Gw-1, heads
            # select position bias
            relative_position_bias = pos[relative_position_index.view(-1)].view(
                group_size[0] * group_size[1], group_size[0] * group_size[1], -1)  # Gh*Gw,Gh*Gw,nH
            relative_position_bias = relative_position_bias.permute(2, 0, 1).contiguous()  # nH, Gh*Gw, Gh*Gw
            attn = attn + relative_position_bias.unsqueeze(0)

        if mask is not None:
            nP = mask.shape[0]
            attn = attn.view(B_ // nP, nP, self.num_heads, N, N) + mask.unsqueeze(1).unsqueeze(
                0)  # (B, nP, nHead, N, N)
            attn = attn.view(-1, self.num_heads, N, N)
            attn = self.softmax(attn)
        else:
            attn = self.softmax(attn)

        attn = self.attn_drop(attn)

        x = (attn @ v).transpose(1, 2).reshape(B_, N, C)
        x = self.proj(x)
        x = self.proj_drop(x)
        return x


class SS2D(nn.Module):
    def __init__(
            self,
            d_model,
            d_state=16,
            d_conv=3,
            expand=2.,
            dt_rank="auto",
            dt_min=0.001,
            dt_max=0.1,
            dt_init="random",
            dt_scale=1.0,
            dt_init_floor=1e-4,
            dropout=0.,
            conv_bias=True,
            bias=False,
            device=None,
            dtype=None,
            **kwargs,
    ):
        factory_kwargs = {"device": device, "dtype": dtype}
        super().__init__()
        self.d_model = d_model
        self.d_state = d_state
        self.d_conv = d_conv
        self.expand = expand
        self.d_inner = int(self.expand * self.d_model)
        self.dt_rank = math.ceil(self.d_model / 16) if dt_rank == "auto" else dt_rank

        self.in_proj = nn.Linear(self.d_model, self.d_inner * 2, bias=bias, **factory_kwargs)
        self.conv2d = nn.Conv2d(
            in_channels=self.d_inner,
            out_channels=self.d_inner,
            groups=self.d_inner,
            bias=conv_bias,
            kernel_size=d_conv,
            padding=(d_conv - 1) // 2,
            **factory_kwargs,
        )
        self.act = nn.SiLU()

        self.x_proj = (
            nn.Linear(self.d_inner, (self.dt_rank + self.d_state * 2), bias=False, **factory_kwargs),
            nn.Linear(self.d_inner, (self.dt_rank + self.d_state * 2), bias=False, **factory_kwargs),
            nn.Linear(self.d_inner, (self.dt_rank + self.d_state * 2), bias=False, **factory_kwargs),
            nn.Linear(self.d_inner, (self.dt_rank + self.d_state * 2), bias=False, **factory_kwargs),
        )
        self.x_proj_weight = nn.Parameter(torch.stack([t.weight for t in self.x_proj], dim=0))  # (K=4, N, inner)
        del self.x_proj

        self.dt_projs = (
            self.dt_init(self.dt_rank, self.d_inner, dt_scale, dt_init, dt_min, dt_max, dt_init_floor,
                         **factory_kwargs),
            self.dt_init(self.dt_rank, self.d_inner, dt_scale, dt_init, dt_min, dt_max, dt_init_floor,
                         **factory_kwargs),
            self.dt_init(self.dt_rank, self.d_inner, dt_scale, dt_init, dt_min, dt_max, dt_init_floor,
                         **factory_kwargs),
            self.dt_init(self.dt_rank, self.d_inner, dt_scale, dt_init, dt_min, dt_max, dt_init_floor,
                         **factory_kwargs),
        )
        self.dt_projs_weight = nn.Parameter(torch.stack([t.weight for t in self.dt_projs], dim=0))  # (K=4, inner, rank)
        self.dt_projs_bias = nn.Parameter(torch.stack([t.bias for t in self.dt_projs], dim=0))  # (K=4, inner)
        del self.dt_projs

        self.A_logs = self.A_log_init(self.d_state, self.d_inner, copies=4, merge=True)  # (K=4, D, N)
        self.Ds = self.D_init(self.d_inner, copies=4, merge=True)  # (K=4, D, N)

        self.selective_scan = selective_scan_fn

        self.out_norm = nn.LayerNorm(self.d_inner)
        self.out_proj = nn.Linear(self.d_inner, self.d_model, bias=bias, **factory_kwargs)
        self.dropout = nn.Dropout(dropout) if dropout > 0. else None

    @staticmethod
    def dt_init(dt_rank, d_inner, dt_scale=1.0, dt_init="random", dt_min=0.001, dt_max=0.1, dt_init_floor=1e-4,
                **factory_kwargs):
        dt_proj = nn.Linear(dt_rank, d_inner, bias=True, **factory_kwargs)

        # Initialize special dt projection to preserve variance at initialization
        dt_init_std = dt_rank ** -0.5 * dt_scale
        if dt_init == "constant":
            nn.init.constant_(dt_proj.weight, dt_init_std)
        elif dt_init == "random":
            nn.init.uniform_(dt_proj.weight, -dt_init_std, dt_init_std)
        else:
            raise NotImplementedError

        # Initialize dt bias so that F.softplus(dt_bias) is between dt_min and dt_max
        dt = torch.exp(
            torch.rand(d_inner, **factory_kwargs) * (math.log(dt_max) - math.log(dt_min))
            + math.log(dt_min)
        ).clamp(min=dt_init_floor)
        # Inverse of softplus: https://github.com/pytorch/pytorch/issues/72759
        inv_dt = dt + torch.log(-torch.expm1(-dt))
        with torch.no_grad():
            dt_proj.bias.copy_(inv_dt)
        # Our initialization would set all Linear.bias to zero, need to mark this one as _no_reinit
        dt_proj.bias._no_reinit = True

        return dt_proj

    @staticmethod
    def A_log_init(d_state, d_inner, copies=1, device=None, merge=True):
        # S4D real initialization
        A = repeat(
            torch.arange(1, d_state + 1, dtype=torch.float32, device=device),
            "n -> d n",
            d=d_inner,
        ).contiguous()
        A_log = torch.log(A)  # Keep A_log in fp32
        if copies > 1:
            A_log = repeat(A_log, "d n -> r d n", r=copies)
            if merge:
                A_log = A_log.flatten(0, 1)
        A_log = nn.Parameter(A_log)
        A_log._no_weight_decay = True
        return A_log

    @staticmethod
    def D_init(d_inner, copies=1, device=None, merge=True):
        # D "skip" parameter
        D = torch.ones(d_inner, device=device)
        if copies > 1:
            D = repeat(D, "n1 -> r n1", r=copies)
            if merge:
                D = D.flatten(0, 1)
        D = nn.Parameter(D)  # Keep in fp32
        D._no_weight_decay = True
        return D

    def forward_core(self, x: torch.Tensor):
        B, C, H, W = x.shape
        L = H * W
        K = 4
        x_hwwh = torch.stack([x.view(B, -1, L), torch.transpose(x, dim0=2, dim1=3).contiguous().view(B, -1, L)], dim=1).view(B, 2, -1, L)
        xs = torch.cat([x_hwwh, torch.flip(x_hwwh, dims=[-1])], dim=1) # (1, 4, 192, 3136)

        x_dbl = torch.einsum("b k d l, k c d -> b k c l", xs.view(B, K, -1, L), self.x_proj_weight)
        dts, Bs, Cs = torch.split(x_dbl, [self.dt_rank, self.d_state, self.d_state], dim=2)
        dts = torch.einsum("b k r l, k d r -> b k d l", dts.view(B, K, -1, L), self.dt_projs_weight)
        xs = xs.float().view(B, -1, L)
        dts = dts.contiguous().float().view(B, -1, L) # (b, k * d, l)
        Bs = Bs.float().view(B, K, -1, L)
        Cs = Cs.float().view(B, K, -1, L) # (b, k, d_state, l)
        Ds = self.Ds.float().view(-1)
        As = -torch.exp(self.A_logs.float()).view(-1, self.d_state)
        dt_projs_bias = self.dt_projs_bias.float().view(-1) # (k * d)
        out_y = self.selective_scan(
            xs, dts,
            As, Bs, Cs, Ds, z=None,
            delta_bias=dt_projs_bias,
            delta_softplus=True,
            return_last_state=False,
        ).view(B, K, -1, L)
        assert out_y.dtype == torch.float

        inv_y = torch.flip(out_y[:, 2:4], dims=[-1]).view(B, 2, -1, L)
        wh_y = torch.transpose(out_y[:, 1].view(B, -1, W, H), dim0=2, dim1=3).contiguous().view(B, -1, L)
        invwh_y = torch.transpose(inv_y[:, 1].view(B, -1, W, H), dim0=2, dim1=3).contiguous().view(B, -1, L)

        return out_y[:, 0], inv_y[:, 0], wh_y, invwh_y

    def forward(self, x: torch.Tensor, **kwargs):
        B, H, W, C = x.shape

        xz = self.in_proj(x)
        x, z = xz.chunk(2, dim=-1)

        x = x.permute(0, 3, 1, 2).contiguous()
        x = self.act(self.conv2d(x))
        y1, y2, y3, y4 = self.forward_core(x)
        assert y1.dtype == torch.float32
        y = y1 + y2 + y3 + y4
        y = torch.transpose(y, dim0=1, dim1=2).contiguous().view(B, H, W, -1)
        y = self.out_norm(y)
        y = y * F.silu(z)
        out = self.out_proj(y)
        if self.dropout is not None:
            out = self.dropout(out)
        return out


class VSSBlock(nn.Module):
    def __init__(
            self,
            hidden_dim: int = 0,
            drop_path: float = 0,
            norm_layer: Callable[..., torch.nn.Module] = partial(nn.LayerNorm, eps=1e-6),
            attn_drop_rate: float = 0,
            d_state: int = 16,
            expand: float = 2.,
            is_light_sr: bool = False,
            **kwargs,
    ):
        super().__init__()
        self.ln_1 = norm_layer(hidden_dim)
        self.self_attention = SS2D(d_model=hidden_dim, d_state=d_state,expand=expand,dropout=attn_drop_rate, **kwargs)
        self.drop_path = DropPath(drop_path)
        self.skip_scale= nn.Parameter(torch.ones(hidden_dim))
        self.conv_blk = CAB(hidden_dim,is_light_sr)
        self.ln_2 = nn.LayerNorm(hidden_dim)
        self.skip_scale2 = nn.Parameter(torch.ones(hidden_dim))



    def forward(self, input, x_size):
        # x [B,HW,C]
        B, L, C = input.shape
        input = input.view(B, *x_size, C).contiguous()  # [B,H,W,C]
        x = self.ln_1(input)
        x = input*self.skip_scale + self.drop_path(self.self_attention(x))
        x = x*self.skip_scale2 + self.conv_blk(self.ln_2(x).permute(0, 3, 1, 2).contiguous()).permute(0, 2, 3, 1).contiguous()
        x = x.view(B, -1, C).contiguous()
        return x


if __name__ == '__main__':
    # 初始化VSSBlock模块，hidden_dim为128
    block = VSSBlock(hidden_dim=128, drop_path=0.1, attn_drop_rate=0.1, d_state=16, expand=2.0, is_light_sr=False)

    # 将模块转移到合适的设备上
    device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
    block = block.to(device)

    # 生成随机输入张量，尺寸为[B, H*W, C]，这里模拟的是批次大小为4，每个图像的尺寸是32x32，通道数为128
    B, H, W, C = 4, 32, 32, 128
    input_tensor = torch.rand(B, H * W, C).to(device)

    # 计算输出
    output_tensor = block(input_tensor, (H, W))

    # 打印输入和输出张量的尺寸
    print("Input tensor size:", input_tensor.size())
    print("Output tensor size:", output_tensor.size())

是否可以集成进 ② ：import torch
import torch.nn as nn
from functools import partial
from torch import Tensor
from typing import Optional

from timm.models.vision_transformer import VisionTransformer, _cfg
from timm.models.registry import register_model
from timm.models.layers import trunc_normal_, lecun_normal_

from timm.models.layers import DropPath, to_2tuple
from timm.models.vision_transformer import _load_weights

import math

from collections import namedtuple

from mamba_ssm.modules.mamba_simple import Mamba
from mamba_ssm.utils.generation import GenerationMixin
from mamba_ssm.utils.hf import load_config_hf, load_state_dict_hf
#################### 结合当前项目引入 #########################
from lib.models.mamba_fetrack.rope import *
import random
# from lib.models.layers.head import build_box_head
import importlib
import lib.train.admin.settings as ws_settings
# from .utils import combine_tokens, recover_tokens
#################################################################
import torch.nn.functional as F
##############
try:
    from mamba_ssm.ops.triton.layernorm import RMSNorm, layer_norm_fn, rms_norm_fn
except ImportError:
    RMSNorm, layer_norm_fn, rms_norm_fn = None, None, None


__all__ = [
    'vim_tiny_patch16_224', 'vim_small_patch16_224', 'vim_base_patch16_224',
    'vim_tiny_patch16_384', 'vim_small_patch16_384', 'vim_base_patch16_384',
]

class MultiScaleEmbed(nn.Module):
    def __init__(self, img_size=224, patch_size=16, stride=16, in_chans=3, embed_dim=64, scales=[1,2,4], norm_layer=None, flatten=True):
        super().__init__()
        img_size = to_2tuple(img_size)
        patch_size = to_2tuple(patch_size)
        self.img_size = img_size
        self.patch_size = patch_size
        self.grid_size = ((img_size[0] - patch_size[0]) // stride + 1, (img_size[1] - patch_size[1]) // stride + 1)
        self.num_patches = self.grid_size[0] * self.grid_size[1]
        self.flatten = flatten
        # Projection layer
        self.proj = nn.Conv2d(in_chans, embed_dim, kernel_size=patch_size, stride=stride)
        self.norm = norm_layer(embed_dim) if norm_layer else nn.Identity()
        # Multi-scale convolutions
        self.additional_convs = nn.ModuleList([
            nn.Sequential(
                nn.Conv2d(in_chans, embed_dim, kernel_size=3, stride=scale, padding=1),
                nn.BatchNorm2d(embed_dim),
                nn.ReLU(inplace=True)
            )
            for scale in scales
        ])
        self.reduce_channels = nn.Conv2d(len(scales) * embed_dim, embed_dim, kernel_size=1)

    def forward(self, x):
        B, C, H, W = x.shape
        x_proj = self.proj(x)
        if self.flatten:
            x_proj = x_proj.flatten(2).transpose(1, 2)  # BCHW -> BNC
        x_proj = self.norm(x_proj)

        # Compute multi-scale features
        multi_scale_features = [F.interpolate(layer(x), size=(self.grid_size[0], self.grid_size[1]), mode='bilinear', align_corners=False) for layer in self.additional_convs]
        multi_scale_features = torch.cat(multi_scale_features, dim=1)  # Concatenate along channel dimension

        # Reduce channels to match x_proj
        multi_scale_features = self.reduce_channels(multi_scale_features)
        
        if self.flatten:
            multi_scale_features = multi_scale_features.flatten(2).transpose(1, 2)  # Ensure BNC shape
        multi_scale_features = self.norm(multi_scale_features)
        
        # Ensure shapes are consistent for concatenation
        if multi_scale_features.shape[1] != x_proj.shape[1]:
            raise ValueError(f"Inconsistent shapes for concatenation: {multi_scale_features.shape[1]} != {x_proj.shape[1]}")
        # Concatenate features
        combined_features = torch.cat([x_proj, multi_scale_features], dim=-1)
        return combined_features


class FeaturePyramid(nn.Module):
    def __init__(self, in_dim, out_dim):
        super().__init__()
        # Define layers for downsampling/upconverting
        self.layer1 = nn.Conv2d(in_dim, out_dim // 2, kernel_size=3, padding=1)
        self.layer2 = nn.Conv2d(out_dim // 2, out_dim, kernel_size=3, padding=1)
    
    def forward(self, x):      
        x1 = self.layer1(x)
        x2 = F.max_pool2d(x1, kernel_size=2, stride=2)
        x2 = self.layer2(x2)
        return x1 + x2
    
class PatchEmbed(nn.Module):
    """ 2D Image to Patch Embedding
    """
    def __init__(self, img_size=224, patch_size=16, stride=16, in_chans=3, embed_dim=768, norm_layer=None, flatten=True):
        super().__init__()
        img_size = to_2tuple(img_size)
        patch_size = to_2tuple(patch_size)
        self.img_size = img_size
        self.patch_size = patch_size
        self.grid_size = ((img_size[0] - patch_size[0]) // stride + 1, (img_size[1] - patch_size[1]) // stride + 1)
        self.num_patches = self.grid_size[0] * self.grid_size[1]
        self.flatten = flatten

        self.proj = nn.Conv2d(in_chans, embed_dim, kernel_size=patch_size, stride=stride)
        self.norm = norm_layer(embed_dim) if norm_layer else nn.Identity()

    def forward(self, x):
        B, C, H, W = x.shape
        x = self.proj(x)
        if self.flatten:
            x = x.flatten(2).transpose(1, 2)  # BCHW -> BNC
        x = self.norm(x) 
        return x
    
class PatchEmbed4_2(nn.Module):
    """
    Image to Patch Embedding with 4 layer convolution
    """

    def __init__(self, img_size=224, patch_size=16, stride=16, in_chans=3, embed_dim=768, norm_layer=None, flatten=True):
        super().__init__()
        img_size = to_2tuple(img_size)
        patch_size = to_2tuple(patch_size)
        self.img_size = img_size
        self.patch_size = patch_size
        new_patch_size = (patch_size[0] // 2, patch_size[1] // 2)
        num_patches = (img_size[1] // patch_size[1]) * (img_size[0] // patch_size[0])
        self.num_patches = num_patches
        self.embed_dim = embed_dim
        self.conv1 = nn.Conv2d(
            in_chans, 64, kernel_size=7, stride=2, padding=3, bias=False
        )  # 112x112
        self.bn1 = nn.BatchNorm2d(64)
        self.relu = nn.ReLU(inplace=True)
        self.conv2 = nn.Conv2d(
            64, 64, kernel_size=3, stride=1, padding=1, bias=False
        )  # 112x112
        self.bn2 = nn.BatchNorm2d(64)
        self.conv3 = nn.Conv2d(64, 64, kernel_size=3, stride=1, padding=1, bias=False)
        self.bn3 = nn.BatchNorm2d(64)

        self.proj = nn.Conv2d(
            64, embed_dim, kernel_size=new_patch_size, stride=new_patch_size
        )
        
        self.flatten = flatten
        self.norm = norm_layer(embed_dim) if norm_layer else nn.Identity()
        

    def forward(self, x):
        x = self.conv1(x)
        x = self.bn1(x)
        x = self.relu(x)

        x = self.conv2(x)
        x = self.bn2(x)
        x = self.relu(x)

        x = self.conv3(x)
        x = self.bn3(x)
        x = self.relu(x)

        x = self.proj(x)  # [B, C, W, H]
        
        if self.flatten:
            x = x.flatten(2).transpose(1, 2)
        x = self.norm(x) 
        return x

    

class Block(nn.Module):
    def __init__(
        self, dim, mixer_cls, norm_cls=nn.LayerNorm, fused_add_norm=False, residual_in_fp32=False,drop_path=0.,
    ):
        super().__init__()
        self.residual_in_fp32 = residual_in_fp32
        self.fused_add_norm = fused_add_norm
        self.mixer = mixer_cls(dim)
        self.norm = norm_cls(dim)
        self.drop_path = DropPath(drop_path) if drop_path > 0. else nn.Identity()
        if self.fused_add_norm:
            assert RMSNorm is not None, "RMSNorm import fails"
            assert isinstance(
                self.norm, (nn.LayerNorm, RMSNorm)
            ), "Only LayerNorm and RMSNorm are supported for fused_add_norm"

    def forward(
        self, hidden_states: Tensor, residual: Optional[Tensor] = None, inference_params=None
    ):
        r"""Pass the input through the encoder layer.

        Args:
            hidden_states: the sequence to the encoder layer (required).
            residual: hidden_states = Mixer(LN(residual))
        """
        if not self.fused_add_norm:
            if residual is None:
                residual = hidden_states
            else:
                residual = residual + self.drop_path(hidden_states)
            
            hidden_states = self.norm(residual.to(dtype=self.norm.weight.dtype))
            if self.residual_in_fp32:
                residual = residual.to(torch.float32)
        else:
            fused_add_norm_fn = rms_norm_fn if isinstance(self.norm, RMSNorm) else layer_norm_fn
            if residual is None:
                hidden_states, residual = fused_add_norm_fn(
                    hidden_states,
                    self.norm.weight,
                    self.norm.bias,
                    residual=residual,
                    prenorm=True,
                    residual_in_fp32=self.residual_in_fp32,
                    eps=self.norm.eps,
                )
            else:
                hidden_states, residual = fused_add_norm_fn(
                    self.drop_path(hidden_states),
                    self.norm.weight,
                    self.norm.bias,
                    residual=residual,
                    prenorm=True,
                    residual_in_fp32=self.residual_in_fp32,
                    eps=self.norm.eps,
                )    
        hidden_states = self.mixer(hidden_states, inference_params=inference_params)
        return hidden_states, residual

    def allocate_inference_cache(self, batch_size, max_seqlen, dtype=None, **kwargs):
        return self.mixer.allocate_inference_cache(batch_size, max_seqlen, dtype=dtype, **kwargs)


def create_block(
    d_model,
    ssm_cfg=None,
    norm_epsilon=1e-5,
    drop_path=0.,
    rms_norm=False,
    residual_in_fp32=False,
    fused_add_norm=False,
    layer_idx=None,
    device=None,
    dtype=None,
    if_bimamba=False,
    bimamba_type="none",
    if_devide_out=False,
    init_layer_scale=None,
):
    if if_bimamba:
        bimamba_type = "v1"
    if ssm_cfg is None:
        ssm_cfg = {}
    factory_kwargs = {"device": device, "dtype": dtype}
    mixer_cls = partial(Mamba, layer_idx=layer_idx, bimamba_type=bimamba_type, if_devide_out=if_devide_out, init_layer_scale=init_layer_scale, **ssm_cfg, **factory_kwargs)
    norm_cls = partial(
        nn.LayerNorm if not rms_norm else RMSNorm, eps=norm_epsilon, **factory_kwargs
    )
    block = Block(
        d_model,
        mixer_cls,
        norm_cls=norm_cls,
        drop_path=drop_path,
        fused_add_norm=fused_add_norm,
        residual_in_fp32=residual_in_fp32,
    )
    block.layer_idx = layer_idx
    return block


# https://github.com/huggingface/transformers/blob/c28d04e9e252a1a099944e325685f14d242ecdcd/src/transformers/models/gpt2/modeling_gpt2.py#L454
def _init_weights(
    module,
    n_layer,
    initializer_range=0.02,  # Now only used for embedding layer.
    rescale_prenorm_residual=True,
    n_residuals_per_layer=1,  # Change to 2 if we have MLP
):
    if isinstance(module, nn.Linear):
        if module.bias is not None:
            if not getattr(module.bias, "_no_reinit", False):
                nn.init.zeros_(module.bias)
    elif isinstance(module, nn.Embedding):
        nn.init.normal_(module.weight, std=initializer_range)

    if rescale_prenorm_residual:
        for name, p in module.named_parameters():
            if name in ["out_proj.weight", "fc2.weight"]:
                nn.init.kaiming_uniform_(p, a=math.sqrt(5))
                with torch.no_grad():
                    p /= math.sqrt(n_residuals_per_layer * n_layer)


def segm_init_weights(m):
    if isinstance(m, nn.Linear):
        trunc_normal_(m.weight, std=0.02)
        if isinstance(m, nn.Linear) and m.bias is not None:
            nn.init.constant_(m.bias, 0)
    elif isinstance(m, nn.Conv2d):
        # NOTE conv was left to pytorch default in my original init
        lecun_normal_(m.weight)
        if m.bias is not None:
            nn.init.zeros_(m.bias)
    elif isinstance(m, (nn.LayerNorm, nn.GroupNorm, nn.BatchNorm2d)):
        nn.init.zeros_(m.bias)
        nn.init.ones_(m.weight)


class VisionMamba(nn.Module):
    def __init__(self, 
                 img_size=224, 
                 patch_size=16, 
                 stride=16,
                 depth=24, 
                 embed_dim=192, 
                 channels=3, 
                 num_classes=1000,
                 ssm_cfg=None, 
                 drop_rate=0.,
                 drop_path_rate=0.1,
                 norm_epsilon: float = 1e-5, 
                 rms_norm: bool = False, 
                 initializer_cfg=None,
                 fused_add_norm=False,
                 residual_in_fp32=False,
                 device=None,
                 dtype=None,
                 ft_seq_len=None,
                 pt_hw_seq_len=14,
                 if_bidirectional=False,
                 final_pool_type='none',
                 if_abs_pos_embed=False,
                 if_rope=False,
                 if_rope_residual=False,
                 flip_img_sequences_ratio=-1.,
                 if_bimamba=False,
                 bimamba_type="none",
                 if_cls_token=False,
                 if_devide_out=False,
                 init_layer_scale=None,
                 use_double_cls_token=False,
                 use_middle_cls_token=False,
                 **kwargs):
        factory_kwargs = {"device": device, "dtype": dtype}
        # add factory_kwargs into kwargs
        kwargs.update(factory_kwargs) 
        super().__init__()
        self.residual_in_fp32 = residual_in_fp32
        self.fused_add_norm = fused_add_norm
        self.if_bidirectional = if_bidirectional
        self.final_pool_type = final_pool_type
        self.if_abs_pos_embed = if_abs_pos_embed
        self.if_rope = if_rope
        self.if_rope_residual = if_rope_residual
        self.flip_img_sequences_ratio = flip_img_sequences_ratio
        # self.if_cls_token = if_cls_token （此处与Mamba源代码不同）
        self.if_cls_token = False
        self.use_double_cls_token = use_double_cls_token
        self.use_middle_cls_token = use_middle_cls_token
        self.num_tokens = 1 if if_cls_token else 0

        # pretrain parameters
        self.num_classes = num_classes
        self.d_model = self.num_features = self.embed_dim = embed_dim  # num_features for consistency with other models
        ############## 原始尺度 ###################
        self.patch_embed = PatchEmbed(
            img_size=img_size, patch_size=patch_size, stride=stride, in_chans=channels, embed_dim=embed_dim)
        # self.patch_embed = PatchEmbed4_2(img_size=img_size, patch_size=patch_size, in_chans=channels, embed_dim=embed_dim)
        num_patches = self.patch_embed.num_patches

        if if_cls_token:
            if use_double_cls_token:
                self.cls_token_head = nn.Parameter(torch.zeros(1, 1, self.embed_dim))
                self.cls_token_tail = nn.Parameter(torch.zeros(1, 1, self.embed_dim))
                self.num_tokens = 2
            else:
                self.cls_token = nn.Parameter(torch.zeros(1, 1, self.embed_dim))
                # self.num_tokens = 1
            
        if if_abs_pos_embed:
            # self.pos_embed = nn.Parameter(torch.zeros(1, num_patches + self.num_tokens, self.embed_dim))
            # 此处与mamba不同,划分了x和z的位置编码
            self.pos_embed_x = nn.Parameter(torch.zeros(1, 256, self.embed_dim))
            self.pos_embed_z = nn.Parameter(torch.zeros(1, 64, self.embed_dim))
            self.pos_drop = nn.Dropout(p=drop_rate)

        if if_rope:
            half_head_dim = embed_dim // 2
            hw_seq_len = img_size // patch_size
            self.rope = VisionRotaryEmbeddingFast(
                dim=half_head_dim,
                pt_seq_len=pt_hw_seq_len,
                ft_seq_len=hw_seq_len
            )

        # TODO: release this comment
        dpr = [x.item() for x in torch.linspace(0, drop_path_rate, depth)]  # stochastic depth decay rule
        # import ipdb;ipdb.set_trace()
        inter_dpr = [0.0] + dpr
        self.drop_path = DropPath(drop_path_rate) if drop_path_rate > 0. else nn.Identity()
                # transformer blocks
        self.layers = nn.ModuleList(
            [
                create_block(
                    embed_dim,
                    ssm_cfg=ssm_cfg,
                    norm_epsilon=norm_epsilon,
                    rms_norm=rms_norm,
                    residual_in_fp32=residual_in_fp32,
                    fused_add_norm=fused_add_norm,
                    layer_idx=i,
                    if_bimamba=if_bimamba,
                    bimamba_type=bimamba_type,
                    drop_path=inter_dpr[i],
                    if_devide_out=if_devide_out,
                    init_layer_scale=init_layer_scale,
                    **factory_kwargs,
                )
                for i in range(depth)
            ]
        )
        
        # output head
        self.norm_f = (nn.LayerNorm if not rms_norm else RMSNorm)(
            embed_dim, eps=norm_epsilon, **factory_kwargs
        )

        # self.pre_logits = nn.Identity()

        # original init
        self.patch_embed.apply(segm_init_weights)
        # 此处与mamba不同，问题在于没有执行head相关操作
        # self.head.apply(segm_init_weights)
        # 在pos_embed中也进行了模板和搜索的划分
        if if_abs_pos_embed:
            trunc_normal_(self.pos_embed_x, std=.02)
            trunc_normal_(self.pos_embed_z, std=.02)
            
        if if_cls_token:
            if use_double_cls_token:
                trunc_normal_(self.cls_token_head, std=.02)
                trunc_normal_(self.cls_token_tail, std=.02)
            else:
                trunc_normal_(self.cls_token, std=.02)

        # mamba init
        self.apply(
            partial(
                _init_weights,
                n_layer=depth,
                **(initializer_cfg if initializer_cfg is not None else {}),
            )
        )


    def allocate_inference_cache(self, batch_size, max_seqlen, dtype=None, **kwargs):
        return {
            i: layer.allocate_inference_cache(batch_size, max_seqlen, dtype=dtype, **kwargs)
            for i, layer in enumerate(self.layers)
        }

    @torch.jit.ignore
    def no_weight_decay(self):
        return {"pos_embed", "cls_token", "dist_token", "cls_token_head", "cls_token_tail"}

    @torch.jit.ignore()
    def load_pretrained(self, checkpoint_path, prefix=""):
        _load_weights(self, checkpoint_path, prefix)

    def forward_features(self, z, x, inference_params=None, if_random_cls_token_position=False, if_random_token_rank=False):
        # taken from https://github.com/rwightman/pytorch-image-models/blob/master/timm/models/vision_transformer.py
        # with slight modifications to add the dist_token
        x = self.patch_embed(x)                  #x.shape = torch.Size([B, 3, 256, 256])  -> torch.Size([2, 256, 384])
        z = self.patch_embed(z)                  #z.shape = torch.Size([B, 3, 128, 128])  -> torch.Size([2, 64, 384])
        print('Patch_x.shape: ', x.shape) # Patch_x.shape:  torch.Size([4, 256, 384])
        x = self.feature_pyramid(x)
        print('Pyramid_x.shape: ', x.shape)
        B, M, _ = x.shape
       
        if self.if_cls_token:                 # False
            if self.use_double_cls_token:
                cls_token_head = self.cls_token_head.expand(B, -1, -1)
                cls_token_tail = self.cls_token_tail.expand(B, -1, -1)
                token_position = [0, M + 1]
                x = torch.cat((cls_token_head, x, cls_token_tail), dim=1)
                M = x.shape[1]
            else:
                if self.use_middle_cls_token:
                    cls_token = self.cls_token.expand(B, -1, -1)
                    token_position = M // 2
                    # add cls token in the middle
                    x = torch.cat((x[:, :token_position, :], cls_token, x[:, token_position:, :]), dim=1)       
                elif if_random_cls_token_position:
                    cls_token = self.cls_token.expand(B, -1, -1)
                    token_position = random.randint(0, M)
                    x = torch.cat((x[:, :token_position, :], cls_token, x[:, token_position:, :]), dim=1)
                    print("token_position: ", token_position)
                else:
                    cls_token = self.cls_token.expand(B, -1, -1)  # stole cls_tokens impl from Phil Wang, thanks
                    token_position = 0
                    x = torch.cat((cls_token, x), dim=1)
                M = x.shape[1]                 
        # 此处由于划分了模板和搜索,pos_embed也需要单独执行
        if self.if_abs_pos_embed:                  # True 
            x = x + self.pos_embed_x               # x = x + positon_embemding =torch.Size([B, 256, 384]) + torch.Size([1, 256, 384]) = torch.Size([B, 256, 384])
            z = z + self.pos_embed_z               # z = z + positon_embemding =torch.Size([B, 64, 384]) + torch.Size([1, 64, 384]) = torch.Size([B, 64, 384])
            x = torch.cat((z, x), dim=1)           # torch.Size([B, 320, 384])
            x = self.pos_drop(x)                   # x.shape = torch.Size([B, 320, 384])
            
        if if_random_token_rank:                   #False
            # 生成随机 shuffle 索引
            shuffle_indices = torch.randperm(M)

            if isinstance(token_position, list):
                print("original value: ", x[0, token_position[0], 0], x[0, token_position[1], 0])
            else:
                print("original value: ", x[0, token_position, 0])
            print("original token_position: ", token_position)

            # 执行 shuffle
            x = x[:, shuffle_indices, :]

            if isinstance(token_position, list):
                # 找到 cls token 在 shuffle 之后的新位置
                new_token_position = [torch.where(shuffle_indices == token_position[i])[0].item() for i in range(len(token_position))]
                token_position = new_token_position
            else:
                # 找到 cls token 在 shuffle 之后的新位置
                token_position = torch.where(shuffle_indices == token_position)[0].item()

            if isinstance(token_position, list):
                print("new value: ", x[0, token_position[0], 0], x[0, token_position[1], 0])
            else:
                print("new value: ", x[0, token_position, 0])
            print("new token_position: ", token_position)


        if_flip_img_sequences = False
        if self.flip_img_sequences_ratio > 0 and (self.flip_img_sequences_ratio - random.random()) > 1e-5:        # False
            x = x.flip([1])
            if_flip_img_sequences = True

        # mamba impl
        residual = None
        hidden_states = x
        if not self.if_bidirectional:                                 # True
            for layer in self.layers:
                if if_flip_img_sequences and self.if_rope:            # False
                    hidden_states = hidden_states.flip([1])
                    if residual is not None:
                        residual = residual.flip([1])

                # rope about
                if self.if_rope:                                       # False
                    hidden_states = self.rope(hidden_states)
                    if residual is not None and self.if_rope_residual:
                        residual = self.rope(residual)

                if if_flip_img_sequences and self.if_rope:             # False
                    hidden_states = hidden_states.flip([1])
                    if residual is not None:
                        residual = residual.flip([1])

                hidden_states, residual = layer(
                    hidden_states, residual, inference_params=inference_params
                )
        
        else:             # False
            # get two layers in a single for-loop
            for i in range(len(self.layers) // 2):
                if self.if_rope:
                    hidden_states = self.rope(hidden_states)
                    if residual is not None and self.if_rope_residual:
                        residual = self.rope(residual)

                hidden_states_f, residual_f = self.layers[i * 2](
                    hidden_states, residual, inference_params=inference_params
                )
                hidden_states_b, residual_b = self.layers[i * 2 + 1](
                    hidden_states.flip([1]), None if residual == None else residual.flip([1]), inference_params=inference_params
                )
                hidden_states = hidden_states_f + hidden_states_b.flip([1])
                residual = residual_f + residual_b.flip([1])
      
        if not self.fused_add_norm:         #False
            if residual is None:
                residual = hidden_states
            else:
                residual = residual + self.drop_path(hidden_states)
            hidden_states = self.norm_f(residual.to(dtype=self.norm_f.weight.dtype))
        else:       #True
            # Set prenorm=False here since we don't need the residual
            fused_add_norm_fn = rms_norm_fn if isinstance(self.norm_f, RMSNorm) else layer_norm_fn
            hidden_states = fused_add_norm_fn(                                         # hidden_states.shape = torch.Size([B, 320, 384])
                self.drop_path(hidden_states),
                self.norm_f.weight,
                self.norm_f.bias,
                eps=self.norm_f.eps,
                residual=residual,
                prenorm=False,
                residual_in_fp32=self.residual_in_fp32,
            )

        # return only cls token if it exists
        if self.if_cls_token:          #False
            if self.use_double_cls_token:
                return (hidden_states[:, token_position[0], :] + hidden_states[:, token_position[1], :]) / 2
            else:
                if self.use_middle_cls_token:
                    return hidden_states[:, token_position, :]
                elif if_random_cls_token_position:
                    return hidden_states[:, token_position, :]
                else:
                    return hidden_states[:, token_position, :]

        if self.final_pool_type == 'none':
            return hidden_states[:, -1, :]
        elif self.final_pool_type == 'mean':         #True
            return hidden_states.mean(dim=1)         #hidden_states.shape = torch.Size([2, 384])
        elif self.final_pool_type == 'max':
            return hidden_states
        elif self.final_pool_type == 'all':
            return hidden_states
        else:
            raise NotImplementedError

    def forward(self, x, return_features=False, inference_params=None, if_random_cls_token_position=False, if_random_token_rank=False):
        x = self.forward_features(x, inference_params, if_random_cls_token_position=if_random_cls_token_position, if_random_token_rank=if_random_token_rank)
        if return_features:
            return x
        x = self.head(x)
        if self.final_pool_type == 'max':
            x = x.max(dim=1)[0]
        return x


@register_model
def vim_tiny_patch16_224_bimambav2_final_pool_mean_abs_pos_embed_with_midclstok_div2(pretrained=False, **kwargs):
    model = VisionMamba(
        patch_size=16, embed_dim=192, depth=24, rms_norm=True, residual_in_fp32=True, fused_add_norm=True, final_pool_type='mean', if_abs_pos_embed=True, if_rope=False, if_rope_residual=False, bimamba_type="v2", if_cls_token=True, if_devide_out=True, use_middle_cls_token=True, **kwargs)
    model.default_cfg = _cfg()
    if pretrained:
        checkpoint = torch.hub.load_state_dict_from_url(
            url="to.do",
            map_location="cpu", check_hash=True
        )
        model.load_state_dict(checkpoint["model"])
    return model

@register_model
def vim_tiny_patch16_stride8_224_bimambav2_final_pool_mean_abs_pos_embed_with_midclstok_div2(pretrained=False, **kwargs):
    model = VisionMamba(
        patch_size=16, stride=8, embed_dim=192, depth=24, rms_norm=True, residual_in_fp32=True, fused_add_norm=True, final_pool_type='mean', if_abs_pos_embed=True, if_rope=False, if_rope_residual=False, bimamba_type="v2", if_cls_token=True, if_devide_out=True, use_middle_cls_token=True, **kwargs)
    model.default_cfg = _cfg()
    if pretrained:
        checkpoint = torch.hub.load_state_dict_from_url(
            url="to.do",
            map_location="cpu", check_hash=True
        )
        model.load_state_dict(checkpoint["model"])
    return model

@register_model
def vim_small_patch16_224_bimambav2_final_pool_mean_abs_pos_embed_with_midclstok_div2(pretrained=False, **kwargs):
    model = VisionMamba(
        patch_size=16, embed_dim=384, depth=24, rms_norm=True, residual_in_fp32=True, fused_add_norm=True, final_pool_type='all', if_abs_pos_embed=True, if_rope=False, if_rope_residual=False, bimamba_type="v2", if_cls_token=True, if_devide_out=True, use_middle_cls_token=True, **kwargs)
    model.default_cfg = _cfg()
    
    if pretrained:
        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

@register_model
def vim_small_patch16_stride8_224_bimambav2_final_pool_mean_abs_pos_embed_with_midclstok_div2(pretrained=False, **kwargs):
    model = VisionMamba(
        patch_size=16, stride=8, embed_dim=384, depth=24, rms_norm=True, residual_in_fp32=True, fused_add_norm=True, final_pool_type='mean', if_abs_pos_embed=True, if_rope=False, if_rope_residual=False, bimamba_type="v2", if_cls_token=True, if_devide_out=True, use_middle_cls_token=True, **kwargs)
    model.default_cfg = _cfg()
    if pretrained:
        checkpoint = torch.hub.load_state_dict_from_url(
            url="to.do",
            map_location="cpu", check_hash=True
        )
        model.load_state_dict(checkpoint["model"])
    return model中？