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import torch
import torch.nn as nn
import torch.nn.functional as F
from functools import partial

from timm.models.layers import DropPath, to_2tuple, trunc_normal_
from timm.models.registry import register_model
from timm.models.vision_transformer import _cfg

import math
from torch.distributions.uniform import Uniform
import numpy as np
import random

__all__ = [
    'pvt_tiny', 'pvt_small', 'pvt_medium', 'pvt_large'
]


class SELayer(nn.Module):
    def __init__(self, channel, reduction=16):
        super(SELayer, self).__init__()
        self.avg_pool = nn.AdaptiveAvgPool2d(1)
        self.fc = nn.Sequential(
            nn.Linear(channel, channel // reduction, bias=False),
            nn.ReLU(inplace=True),
            nn.Linear(channel // reduction, channel, bias=False),
            nn.Sigmoid()
        )

    def forward(self, x):
        b, c, _, _ = x.size()
        y = self.avg_pool(x).view(b, c)
        y = self.fc(y).view(b, c, 1, 1)
        return x * y.expand_as(x)
        

class Regression(nn.Module):
    def __init__(self):
        super(Regression, self).__init__()

        self.v1 = nn.Sequential(
            nn.Upsample(scale_factor=2, mode='bilinear', align_corners=True),
            nn.Conv2d(256, 128, 3, padding=1, dilation=1),
            nn.BatchNorm2d(128), nn.ReLU(inplace=True))

        self.v2 = nn.Sequential(
            nn.Upsample(scale_factor=2, mode='bilinear', align_corners=True),
            nn.Conv2d(512, 256, 3, padding=1, dilation=1),
            nn.BatchNorm2d(256), nn.ReLU(inplace=True))
            
        self.v3 = nn.Sequential(
            nn.Upsample(scale_factor=2, mode='bilinear', align_corners=True),
            nn.Conv2d(1024, 512, 3, padding=1, dilation=1), nn.BatchNorm2d(512),
            nn.ReLU(inplace=True))
        
        self.ca2 = nn.Sequential(ChannelAttention(512),
                    nn.Conv2d(512, 512, kernel_size = 3, stride = 1, padding = 1 ),
                    nn.BatchNorm2d(512), nn.ReLU(inplace=True))
                    
        self.ca1 = nn.Sequential(ChannelAttention(256),
                    nn.Conv2d(256, 256, kernel_size = 3, stride = 1, padding = 1 ),
                    nn.BatchNorm2d(256), nn.ReLU(inplace=True))
                    
        self.ca0 = nn.Sequential(ChannelAttention(128),
                    nn.Conv2d(128, 128, kernel_size = 3, stride = 1, padding = 1 ),
                    nn.BatchNorm2d(128), nn.ReLU(inplace=True))

        self.res2 = nn.Sequential(
            nn.Conv2d(512, 256, 3, padding=1, dilation=1), nn.BatchNorm2d(256),
            nn.ReLU(inplace=True),
            nn.Conv2d(256, 128, 3, padding=1, dilation=1), nn.BatchNorm2d(128),
            nn.ReLU(inplace=True),            
            nn.Conv2d(128, 1, 3, padding=1, dilation=1),
            nn.ReLU(inplace=True))
            
        self.res1 = nn.Sequential(
            nn.Conv2d(256, 128, 3, padding=1, dilation=1), nn.BatchNorm2d(128),
            nn.ReLU(inplace=True),
            nn.Conv2d(128, 64, 3, padding=1, dilation=1), nn.BatchNorm2d(64),
            nn.ReLU(inplace=True),            
            nn.Conv2d(64, 1, 3, padding=1, dilation=1),
            nn.ReLU(inplace=True))
            
        self.res0 = nn.Sequential(
            nn.Conv2d(128, 64, 3, padding=1, dilation=1), nn.BatchNorm2d(64),
            nn.ReLU(inplace=True),            
            nn.Conv2d(64, 1, 3, padding=1, dilation=1),
            nn.ReLU(inplace=True))
            
        self.noise2 = DropOutDecoder(1, 512, 512)
        self.noise1 = FeatureDropDecoder(1, 256, 256)
        self.noise0 = FeatureNoiseDecoder(1, 128, 128)
        
        self.upsam2 = nn.Upsample(scale_factor=2, mode='bilinear', align_corners=True)
        self.upsam4 = nn.Upsample(scale_factor=4, mode='bilinear', align_corners=True)
        
        self.conv1 = nn.Conv2d(1024, 512, kernel_size=1, bias=False)
        self.conv2 = nn.Conv2d(512, 256, kernel_size=1, bias=False)
        self.conv3 = nn.Conv2d(256, 128, kernel_size=1, bias=False)
        self.conv4 = nn.Conv2d(128, 1, kernel_size=1, bias=False)

        #cls2.view(8, 1024, 1, 1))
        
        self.init_param()

    def forward(self, x, cls):
        x0 = x[0]; x1 = x[1]; x2 = x[2]; x3 = x[3] 
        cls0 = cls[0].view(cls[0].shape[0], cls[0].shape[1], 1, 1)
        cls1 = cls[1].view(cls[1].shape[0], cls[1].shape[1], 1, 1) 
        cls2 = cls[2].view(cls[2].shape[0], cls[2].shape[1], 1, 1)
        
        x2_1 = self.ca2(x2)+self.v3(x3)
        x1_1 = self.ca1(x1)+self.v2(x2_1)
        x0_1 = self.ca0(x0)+self.v1(x1_1)
        
        if self.training:
            yc2 = self.conv4(self.conv3(self.conv2(self.noise2(self.conv1(cls2))))).squeeze()
            yc1 = self.conv4(self.conv3(self.noise1(self.conv2(cls1)))).squeeze()
            yc0 = self.conv4(self.noise0(self.conv3(cls0))).squeeze()
            
            y2 = self.res2(self.upsam4(self.noise2(x2_1)))
            y1 = self.res1(self.upsam2(self.noise1(x1_1)))
            y0 = self.res0(self.noise0(x0_1))
            
        else:
            yc2 = self.conv4(self.conv3(self.conv2(self.conv1(cls2)))).squeeze()
            yc1 = self.conv4(self.conv3(self.conv2(cls1))).squeeze()
            yc0 = self.conv4(self.conv3(cls0)).squeeze()
        
            y2 = self.res2(self.upsam4(x2_1))
            y1 = self.res1(self.upsam2(x1_1))
            y0 = self.res0(x0_1)
            
        return [y0, y1, y2], [yc0, yc1, yc2]

    def init_param(self):
        for m in self.modules():
            if isinstance(m, nn.Conv2d):
                nn.init.normal_(m.weight, std=0.01)
                if m.bias is not None:
                    nn.init.constant_(m.bias, 0)
            elif isinstance(m, nn.BatchNorm2d):
                nn.init.constant_(m.weight, 1)
                nn.init.constant_(m.bias, 0)


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


       
def upsample(in_channels, out_channels, upscale, kernel_size=3):
    # A series of x 2 upsamling until we get to the upscale we want
    layers = []
    conv1x1 = nn.Conv2d(in_channels, out_channels, kernel_size=1, bias=False)
    nn.init.kaiming_normal_(conv1x1.weight.data, nonlinearity='relu')
    layers.append(conv1x1)
    for i in range(int(math.log(upscale, 2))):
        layers.append(PixelShuffle(out_channels, scale=2))
    return nn.Sequential(*layers)

    
    
class FeatureDropDecoder(nn.Module):
    def __init__(self, upscale, conv_in_ch, num_classes):
        super(FeatureDropDecoder, self).__init__()
        self.upsample = upsample(conv_in_ch, num_classes, upscale=upscale)

    def feature_dropout(self, x):
        attention = torch.mean(x, dim=1, keepdim=True)
        max_val, _ = torch.max(attention.view(x.size(0), -1), dim=1, keepdim=True)
        threshold = max_val * np.random.uniform(0.7, 0.9)
        threshold = threshold.view(x.size(0), 1, 1, 1).expand_as(attention)
        drop_mask = (attention < threshold).float()
        return x.mul(drop_mask)

    def forward(self, x):
        x = self.feature_dropout(x)
        return x


class FeatureNoiseDecoder(nn.Module):
    def __init__(self, upscale, conv_in_ch, num_classes, uniform_range=0.3):
        super(FeatureNoiseDecoder, self).__init__()
        self.upsample = upsample(conv_in_ch, num_classes, upscale=upscale)
        self.uni_dist = Uniform(-uniform_range, uniform_range)

    def feature_based_noise(self, x):
        noise_vector = self.uni_dist.sample(x.shape[1:]).to(x.device).unsqueeze(0)
        x_noise = x.mul(noise_vector) + x
        return x_noise

    def forward(self, x):
        x = self.feature_based_noise(x)
        return x

class DropOutDecoder(nn.Module):
    def __init__(self, upscale, conv_in_ch, num_classes, drop_rate=0.3, spatial_dropout=True):
        super(DropOutDecoder, self).__init__()
        self.dropout = nn.Dropout2d(p=drop_rate) if spatial_dropout else nn.Dropout(drop_rate)
        self.upsample = upsample(conv_in_ch, num_classes, upscale=upscale)

    def forward(self, x):
        x = self.dropout(x)
        return x


## ChannelAttetion
class ChannelAttention(nn.Module):
    def __init__(self, in_planes, ratio=16):
        super(ChannelAttention, self).__init__()
        self.avg_pool = nn.AdaptiveAvgPool2d(1)
           
        self.fc = nn.Sequential(
            nn.Linear(in_planes,in_planes // ratio, bias = False),
            nn.ReLU(inplace = True),
            nn.Linear(in_planes // ratio, in_planes, bias = False)
        )
        self.sigmoid = nn.Sigmoid()
        for m in self.modules():
            if isinstance(m, nn.Conv2d):
                nn.init.kaiming_normal_(m.weight, mode='fan_out', nonlinearity='relu')

    def forward(self, in_feature):
        x = in_feature
        b, c, _, _ = in_feature.size()
        avg_out = self.fc(self.avg_pool(x).view(b,c)).view(b, c, 1, 1)
        out = avg_out
        return self.sigmoid(out).expand_as(in_feature) * in_feature


class Attention(nn.Module):
    def __init__(self, dim, num_heads=8, qkv_bias=False, qk_scale=None, attn_drop=0., proj_drop=0., sr_ratio=1):
        super().__init__()
        assert dim % num_heads == 0, f"dim {dim} should be divided by num_heads {num_heads}."

        self.dim = dim
        self.num_heads = num_heads
        head_dim = dim // num_heads
        self.scale = qk_scale or head_dim ** -0.5

        self.q = nn.Linear(dim, dim, bias=qkv_bias)
        self.kv = nn.Linear(dim, dim * 2, bias=qkv_bias)
        self.attn_drop = nn.Dropout(attn_drop)
        self.proj = nn.Linear(dim, dim)
        self.proj_drop = nn.Dropout(proj_drop)

        self.sr_ratio = sr_ratio
        if sr_ratio > 1:
            self.sr = nn.Conv2d(dim, dim, kernel_size=sr_ratio, stride=sr_ratio)
            self.norm = nn.LayerNorm(dim)

    def forward(self, x, H, W):
        B, N, C = x.shape
        q = self.q(x).reshape(B, N, self.num_heads, C // self.num_heads).permute(0, 2, 1, 3)
        
        if self.sr_ratio > 4:
            x_ = x.permute(0, 2, 1).reshape(B, C, H, W)
            x_ = self.sr(x_).reshape(B, C, -1).permute(0, 2, 1)
            x_ = self.norm(x_)
            kv = self.kv(x_).reshape(B, -1, 2, self.num_heads, C // self.num_heads).permute(2, 0, 3, 1, 4)
        else:
            kv = self.kv(x).reshape(B, -1, 2, self.num_heads, C // self.num_heads).permute(2, 0, 3, 1, 4)
        k, v = kv[0], kv[1]

        attn = (q @ k.transpose(-2, -1)) * self.scale
        attn = attn.softmax(dim=-1)
        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 Block(nn.Module):

    def __init__(self, dim, num_heads, mlp_ratio=4., qkv_bias=False, qk_scale=None, drop=0., attn_drop=0.,

                 drop_path=0., act_layer=nn.GELU, norm_layer=nn.LayerNorm, sr_ratio=1):
        super().__init__()
        self.norm1 = norm_layer(dim)
        self.attn = Attention(
            dim,
            num_heads=num_heads, qkv_bias=qkv_bias, qk_scale=qk_scale,
            attn_drop=attn_drop, proj_drop=drop, sr_ratio=sr_ratio)
        # NOTE: drop path for stochastic depth, we shall see if this is better than dropout here
        self.drop_path = DropPath(drop_path) if drop_path > 0. else nn.Identity()
        self.norm2 = norm_layer(dim)
        mlp_hidden_dim = int(dim * mlp_ratio)
        self.mlp = Mlp(in_features=dim, hidden_features=mlp_hidden_dim, act_layer=act_layer, drop=drop)

    def forward(self, x, H, W):
        x = x + self.drop_path(self.attn(self.norm1(x), H, W))
        x = x + self.drop_path(self.mlp(self.norm2(x)))

        return x


class PatchEmbed(nn.Module):
    """ Image to Patch Embedding

    """

    def __init__(self, img_size=224, patch_size=16, in_chans=3, embed_dim=768):
        super().__init__()
        img_size = to_2tuple(img_size)
        patch_size = to_2tuple(patch_size)

        self.img_size = img_size
        self.patch_size = patch_size
        # assert img_size[0] % patch_size[0] == 0 and img_size[1] % patch_size[1] == 0, \
        #     f"img_size {img_size} should be divided by patch_size {patch_size}."
        self.H, self.W = img_size[0] // patch_size[0], img_size[1] // patch_size[1]
        self.num_patches = self.H * self.W
        self.proj = nn.Conv2d(in_chans, embed_dim, kernel_size=patch_size, stride=patch_size)
        self.norm = nn.LayerNorm(embed_dim)

    def forward(self, x):
        B, C, H, W = x.shape

        x = self.proj(x).flatten(2).transpose(1, 2)
        x = self.norm(x)
        H, W = H // self.patch_size[0], W // self.patch_size[1]

        return x, (H, W)


class PyramidVisionTransformer(nn.Module):
    def __init__(self, img_size=224, patch_size=16, in_chans=3, num_classes=1000, embed_dims=[64, 128, 256, 512],

                 num_heads=[1, 2, 4, 8], mlp_ratios=[4, 4, 4, 4], qkv_bias=False, qk_scale=None, drop_rate=0.,

                 attn_drop_rate=0., drop_path_rate=0., norm_layer=nn.LayerNorm,

                 depths=[3, 4, 6, 3], sr_ratios=[8, 4, 2, 1], num_stages=4):
        super().__init__()
        self.num_classes = num_classes
        self.depths = depths
        self.num_stages = num_stages

        dpr = [x.item() for x in torch.linspace(0, drop_path_rate, sum(depths))]  # stochastic depth decay rule
        cur = 0

        for i in range(num_stages):
            patch_embed = PatchEmbed(img_size=img_size if i == 0 else img_size // (2 ** (i + 1)),
                                     patch_size=patch_size if i == 0 else 2,
                                     in_chans=in_chans if i == 0 else embed_dims[i - 1],
                                     embed_dim=embed_dims[i])
            num_patches = patch_embed.num_patches if i == 0 else patch_embed.num_patches + 1
            pos_embed = nn.Parameter(torch.zeros(1, num_patches, embed_dims[i]))
            pos_drop = nn.Dropout(p=drop_rate)

            block = nn.ModuleList([Block(
                dim=embed_dims[i], num_heads=num_heads[i], mlp_ratio=mlp_ratios[i], qkv_bias=qkv_bias,
                qk_scale=qk_scale, drop=drop_rate, attn_drop=attn_drop_rate, drop_path=dpr[cur + j],
                norm_layer=norm_layer, sr_ratio=sr_ratios[i])
                for j in range(depths[i])])
            cur += depths[i]

            setattr(self, f"patch_embed{i + 1}", patch_embed)
            setattr(self, f"pos_embed{i + 1}", pos_embed)
            setattr(self, f"pos_drop{i + 1}", pos_drop)
            setattr(self, f"block{i + 1}", block)

        self.norm = norm_layer(embed_dims[3])

        # cls_token
        self.cls_token_1 = nn.Parameter(torch.zeros(1, 1, embed_dims[1]))
        self.cls_token_2 = nn.Parameter(torch.zeros(1, 1, embed_dims[2]))
        self.cls_token_3 = nn.Parameter(torch.zeros(1, 1, embed_dims[3]))

        # classification head
        self.head = nn.Linear(embed_dims[3], num_classes) if num_classes > 0 else nn.Identity()
        
                
        self.regression = Regression()
        
        # init weights
        for i in range(num_stages):
            pos_embed = getattr(self, f"pos_embed{i + 1}")
            trunc_normal_(pos_embed, std=.02)
        trunc_normal_(self.cls_token_1, std=.02)
        trunc_normal_(self.cls_token_2, std=.02)
        trunc_normal_(self.cls_token_3, std=.02)
        self.apply(self._init_weights)


    def _init_weights(self, m):
        if isinstance(m, nn.Linear):
            trunc_normal_(m.weight, std=.02)
            if isinstance(m, nn.Linear) and m.bias is not None:
                nn.init.constant_(m.bias, 0)
        elif isinstance(m, nn.LayerNorm):
            nn.init.constant_(m.bias, 0)
            nn.init.constant_(m.weight, 1.0)

    @torch.jit.ignore
    def no_weight_decay(self):
        # return {'pos_embed', 'cls_token'} # has pos_embed may be better
        return {'cls_token'}

    def get_classifier(self):
        return self.head

    def reset_classifier(self, num_classes, global_pool=''):
        self.num_classes = num_classes
        self.head = nn.Linear(self.embed_dim, num_classes) if num_classes > 0 else nn.Identity()

    def _get_pos_embed(self, pos_embed, patch_embed, H, W):
        if H * W == self.patch_embed1.num_patches:
            return pos_embed
        else:
            return F.interpolate(
                pos_embed.reshape(1, patch_embed.H, patch_embed.W, -1).permute(0, 3, 1, 2),
                size=(H, W), mode="bilinear").reshape(1, -1, H * W).permute(0, 2, 1)

    def forward_features(self, x):
        B = x.shape[0]
        outputs = list()
        cls_output = list()
        
        for i in range(self.num_stages):
            patch_embed = getattr(self, f"patch_embed{i + 1}")
            pos_embed = getattr(self, f"pos_embed{i + 1}")
            pos_drop = getattr(self, f"pos_drop{i + 1}")
            block = getattr(self, f"block{i + 1}")
            x, (H, W) = patch_embed(x)
            
            if i == 0:
                pos_embed = self._get_pos_embed(pos_embed, patch_embed, H, W)
            elif i == 1:
                cls_tokens = self.cls_token_1.expand(B, -1, -1)
                x = torch.cat((cls_tokens, x), dim=1)
                pos_embed_ = self._get_pos_embed(pos_embed[:, 1:], patch_embed, H, W)
                pos_embed = torch.cat((pos_embed[:, 0:1], pos_embed_), dim=1)
            elif i == 2:
                cls_tokens = self.cls_token_2.expand(B, -1, -1)
                x = torch.cat((cls_tokens, x), dim=1)
                pos_embed_ = self._get_pos_embed(pos_embed[:, 1:], patch_embed, H, W)
                pos_embed = torch.cat((pos_embed[:, 0:1], pos_embed_), dim=1)
            
            elif i == 3:
                cls_tokens = self.cls_token_3.expand(B, -1, -1)
                x = torch.cat((cls_tokens, x), dim=1)
                pos_embed_ = self._get_pos_embed(pos_embed[:, 1:], patch_embed, H, W)
                pos_embed = torch.cat((pos_embed[:, 0:1], pos_embed_), dim=1)
            
                
            x = pos_drop(x + pos_embed)
            for blk in block:
                x = blk(x, H, W)
            
            if i == 0:
                x = x.reshape(B, H, W, -1).permute(0, 3, 1, 2).contiguous()
            else:
            
                x_cls = x[:,1,:]
                x = x[:,1:,:].reshape(B, H, W, -1).permute(0, 3, 1, 2).contiguous()
                cls_output.append(x_cls)
            
                
            outputs.append(x)
        return outputs, cls_output


    def forward(self, label_x, unlabel_x=None):    

        if self.training:
            # labeled image processing
            label_x, l_cls = self.forward_features(label_x)
            out_label_x, out_cls_l = self.regression(label_x, l_cls)
            label_x_1, label_x_2, label_x_3 = out_label_x
            
            B,C,H,W = label_x_1.size()
            label_sum = label_x_1.view([B, -1]).sum(1).unsqueeze(1).unsqueeze(2).unsqueeze(3)
            label_normed = label_x_1 / (label_sum + 1e-6)
         
            # unlabeled image processing
            B,C,H,W = unlabel_x.shape
            unlabel_x, ul_cls = self.forward_features(unlabel_x)
            out_unlabel_x, out_cls_ul = self.regression(unlabel_x, ul_cls)
            y0, y1, y2 = out_unlabel_x
            
            unlabel_x_1 = self.generate_feature_patches(y0)
            unlabel_x_2 = self.generate_feature_patches(y1)
            unlabel_x_3 = self.generate_feature_patches(y2)

            assert unlabel_x_1.shape[0] == B * 5
            assert unlabel_x_2.shape[0] == B * 5
            assert unlabel_x_3.shape[0] == B * 5

            unlabel_x_1 = torch.split(unlabel_x_1, split_size_or_sections=B, dim=0)
            unlabel_x_2 = torch.split(unlabel_x_2, split_size_or_sections=B, dim=0)
            unlabel_x_3 = torch.split(unlabel_x_3, split_size_or_sections=B, dim=0)
            
            return [label_x_1, label_x_2, label_x_3], [unlabel_x_1, unlabel_x_2, unlabel_x_3], label_normed, out_cls_l, out_cls_ul
            
        
        else:
            
            label_x, l_cls = self.forward_features(label_x)
            out_label_x, out_cls_l = self.regression(label_x, l_cls)
            label_x_1, label_x_2, label_x_3 = out_label_x
            B,C,H,W = label_x_1.size()
            label_sum = label_x_1.view([B, -1]).sum(1).unsqueeze(1).unsqueeze(2).unsqueeze(3)
            label_normed = label_x_1 / (label_sum + 1e-6)
        
            return [label_x_1, label_x_2, label_x_3], label_normed


    def generate_feature_patches(self, unlabel_x, ratio=0.75):
        # unlabeled image processing
        
        unlabel_x_1 = unlabel_x
        b, c, h, w = unlabel_x.shape

        center_x = random.randint(h // 2 - (h - h * ratio) // 2, h // 2 + (h - h * ratio) // 2)
        center_y = random.randint(w // 2 - (w - w * ratio) // 2, w // 2 + (w - w * ratio) // 2)

        new_h2 = int(h * ratio)
        new_w2 = int(w * ratio)  # 48*48
        unlabel_x_2 = unlabel_x[:, :, center_x - new_h2 // 2:center_x + new_h2 // 2,
                      center_y - new_w2 // 2:center_y + new_w2 // 2]

        new_h3 = int(new_h2 * ratio)
        new_w3 = int(new_w2 * ratio)
        unlabel_x_3 = unlabel_x[:, :, center_x - new_h3 // 2:center_x + new_h3 // 2,
                      center_y - new_w3 // 2:center_y + new_w3 // 2]

        new_h4 = int(new_h3 * ratio)
        new_w4 = int(new_w3 * ratio)
        unlabel_x_4 = unlabel_x[:, :, center_x - new_h4 // 2:center_x + new_h4 // 2,
                      center_y - new_w4 // 2:center_y + new_w4 // 2]

        new_h5 = int(new_h4 * ratio)
        new_w5 = int(new_w4 * ratio)
        unlabel_x_5 = unlabel_x[:, :, center_x - new_h5 // 2:center_x + new_h5 // 2,
                      center_y - new_w5 // 2:center_y + new_w5 // 2]

        unlabel_x_2 = nn.functional.interpolate(unlabel_x_2, size=(h, w), mode='bilinear')
        unlabel_x_3 = nn.functional.interpolate(unlabel_x_3, size=(h, w), mode='bilinear')
        unlabel_x_4 = nn.functional.interpolate(unlabel_x_4, size=(h, w), mode='bilinear')
        unlabel_x_5 = nn.functional.interpolate(unlabel_x_5, size=(h, w), mode='bilinear')

        unlabel_x = torch.cat([unlabel_x_1, unlabel_x_2, unlabel_x_3, unlabel_x_4, unlabel_x_5], dim=0)

        return unlabel_x

def _conv_filter(state_dict, patch_size=16):
    """ convert patch embedding weight from manual patchify + linear proj to conv"""
    out_dict = {}
    for k, v in state_dict.items():
        if 'patch_embed.proj.weight' in k:
            v = v.reshape((v.shape[0], 3, patch_size, patch_size))
        out_dict[k] = v

    return out_dict


@register_model
def pvt_tiny(pretrained=False, **kwargs):
    model = PyramidVisionTransformer(
        patch_size=4, embed_dims=[64, 128, 320, 512], num_heads=[1, 2, 5, 8], mlp_ratios=[8, 8, 4, 4], qkv_bias=True,
        norm_layer=partial(nn.LayerNorm, eps=1e-6), depths=[2, 2, 2, 2], sr_ratios=[8, 4, 2, 1],
        **kwargs)
    model.default_cfg = _cfg()

    return model


@register_model
def pvt_small(pretrained=False, **kwargs):
    model = PyramidVisionTransformer(
        patch_size=4, embed_dims=[64, 128, 320, 512], num_heads=[1, 2, 5, 8], mlp_ratios=[8, 8, 4, 4], qkv_bias=True,
        norm_layer=partial(nn.LayerNorm, eps=1e-6), depths=[3, 4, 6, 3], sr_ratios=[8, 4, 2, 1], **kwargs)
    model.default_cfg = _cfg()

    return model


@register_model
def pvt_medium(pretrained=False, **kwargs):
    model = PyramidVisionTransformer(
        patch_size=4, embed_dims=[64, 128, 320, 512], num_heads=[1, 2, 5, 8], mlp_ratios=[8, 8, 4, 4], qkv_bias=True,
        norm_layer=partial(nn.LayerNorm, eps=1e-6), depths=[3, 4, 18, 3], sr_ratios=[8, 4, 2, 1],
        **kwargs)
    model.default_cfg = _cfg()

    return model


@register_model
def pvt_large(pretrained=False, **kwargs):
    model = PyramidVisionTransformer(
        patch_size=4, embed_dims=[64, 128, 320, 512], num_heads=[1, 2, 5, 8], mlp_ratios=[8, 8, 4, 4], qkv_bias=True,
        norm_layer=partial(nn.LayerNorm, eps=1e-6), depths=[3, 8, 27, 3], sr_ratios=[8, 4, 2, 1],
        **kwargs)
    model.default_cfg = _cfg()

    return model
    
@register_model
def pvt_treeformer(pretrained=False, **kwargs):
    model = PyramidVisionTransformer(
        patch_size=4, embed_dims=[128, 256, 512, 1024], num_heads=[4, 8, 16, 32], mlp_ratios=[4, 4, 4, 4], qkv_bias=True,
        norm_layer=partial(nn.LayerNorm, eps=1e-6), depths=[3, 4, 18, 3], sr_ratios=[8, 4, 2, 1],
        **kwargs)
    model.default_cfg = _cfg()

    return model