File size: 7,938 Bytes
62a0e4e
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
# Copyright (c) Meta Platforms, Inc. and affiliates.
#
# This source code is licensed under the Apache License, Version 2.0
# found in the LICENSE file in the root directory of this source tree.

import math

import torch
import torch.nn as nn
import torch.nn.functional as F
from mmseg.models.builder import BACKBONES
from torch.nn.init import normal_

from ...ops.modules import MSDeformAttn
from .adapter_modules import InteractionBlock, InteractionBlockWithCls, SpatialPriorModule, deform_inputs
from .vit import TIMMVisionTransformer


@BACKBONES.register_module()
class ViTAdapter(TIMMVisionTransformer):
    def __init__(
        self,
        pretrain_size=224,
        num_heads=12,
        conv_inplane=64,
        n_points=4,
        deform_num_heads=6,
        init_values=0.0,
        interaction_indexes=None,
        with_cffn=True,
        cffn_ratio=0.25,
        deform_ratio=1.0,
        add_vit_feature=True,
        pretrained=None,
        use_extra_extractor=True,
        freeze_vit=False,
        use_cls=True,
        with_cp=False,
        *args,
        **kwargs
    ):

        super().__init__(num_heads=num_heads, pretrained=pretrained, with_cp=with_cp, *args, **kwargs)
        if freeze_vit:
            for param in self.parameters():
                param.requires_grad = False

        # self.num_classes = 80
        self.use_cls = use_cls
        if not self.use_cls:
            self.cls_token = None
        self.num_block = len(self.blocks)
        self.pretrain_size = (pretrain_size, pretrain_size)
        self.interaction_indexes = interaction_indexes
        self.add_vit_feature = add_vit_feature
        embed_dim = self.embed_dim

        block_fn = InteractionBlockWithCls if use_cls else InteractionBlock

        self.level_embed = nn.Parameter(torch.zeros(3, embed_dim))
        self.spm = SpatialPriorModule(inplanes=conv_inplane, embed_dim=embed_dim, with_cp=False)
        self.interactions = nn.Sequential(
            *[
                block_fn(
                    dim=embed_dim,
                    num_heads=deform_num_heads,
                    n_points=n_points,
                    init_values=init_values,
                    drop_path=self.drop_path_rate,
                    norm_layer=self.norm_layer,
                    with_cffn=with_cffn,
                    cffn_ratio=cffn_ratio,
                    deform_ratio=deform_ratio,
                    extra_extractor=((True if i == len(interaction_indexes) - 1 else False) and use_extra_extractor),
                    with_cp=with_cp,
                )
                for i in range(len(interaction_indexes))
            ]
        )
        self.up = nn.ConvTranspose2d(embed_dim, embed_dim, 2, 2)
        self.norm1 = nn.SyncBatchNorm(embed_dim)
        self.norm2 = nn.SyncBatchNorm(embed_dim)
        self.norm3 = nn.SyncBatchNorm(embed_dim)
        self.norm4 = nn.SyncBatchNorm(embed_dim)

        self.up.apply(self._init_weights)
        self.spm.apply(self._init_weights)
        self.interactions.apply(self._init_weights)
        self.apply(self._init_deform_weights)
        normal_(self.level_embed)

    def _init_weights(self, m):
        if isinstance(m, nn.Linear):
            torch.nn.init.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.LayerNorm) or isinstance(m, nn.BatchNorm2d):
            nn.init.constant_(m.bias, 0)
            nn.init.constant_(m.weight, 1.0)
        elif isinstance(m, nn.Conv2d) or isinstance(m, nn.ConvTranspose2d):
            fan_out = m.kernel_size[0] * m.kernel_size[1] * m.out_channels
            fan_out //= m.groups
            m.weight.data.normal_(0, math.sqrt(2.0 / fan_out))
            if m.bias is not None:
                m.bias.data.zero_()

    def _get_pos_embed(self, pos_embed, H, W):
        pos_embed = pos_embed.reshape(
            1, self.pretrain_size[0] // self.patch_size, self.pretrain_size[1] // self.patch_size, -1
        ).permute(0, 3, 1, 2)
        pos_embed = (
            F.interpolate(pos_embed, size=(H, W), mode="bicubic", align_corners=False)
            .reshape(1, -1, H * W)
            .permute(0, 2, 1)
        )
        return pos_embed

    def _init_deform_weights(self, m):
        if isinstance(m, MSDeformAttn):
            m._reset_parameters()

    def _add_level_embed(self, c2, c3, c4):
        c2 = c2 + self.level_embed[0]
        c3 = c3 + self.level_embed[1]
        c4 = c4 + self.level_embed[2]
        return c2, c3, c4

    def forward(self, x):
        deform_inputs1, deform_inputs2 = deform_inputs(x, self.patch_size)

        # SPM forward
        c1, c2, c3, c4 = self.spm(x)
        c2, c3, c4 = self._add_level_embed(c2, c3, c4)
        c = torch.cat([c2, c3, c4], dim=1)

        # Patch Embedding forward
        H_c, W_c = x.shape[2] // 16, x.shape[3] // 16
        x, H_toks, W_toks = self.patch_embed(x)
        # print("H_toks, W_toks =", H_toks, W_toks)
        bs, n, dim = x.shape
        pos_embed = self._get_pos_embed(self.pos_embed[:, 1:], H_toks, W_toks)
        if self.use_cls:
            cls_token = self.cls_token.expand(x.shape[0], -1, -1)  # stole cls_tokens impl from Phil Wang, thanks
            x = torch.cat((cls_token, x), dim=1)
            pos_embed = torch.cat((self.pos_embed[:, :1], pos_embed), dim=1)
        x = self.pos_drop(x + pos_embed)
        # For CLIP
        x = self.norm_pre(x)

        # Interaction
        if self.use_cls:
            cls, x = (
                x[
                    :,
                    :1,
                ],
                x[
                    :,
                    1:,
                ],
            )
        outs = list()
        for i, layer in enumerate(self.interactions):
            indexes = self.interaction_indexes[i]
            if self.use_cls:
                x, c, cls = layer(
                    x,
                    c,
                    cls,
                    self.blocks[indexes[0] : indexes[-1] + 1],
                    deform_inputs1,
                    deform_inputs2,
                    H_c,
                    W_c,
                    H_toks,
                    W_toks,
                )
            else:
                x, c = layer(
                    x,
                    c,
                    self.blocks[indexes[0] : indexes[-1] + 1],
                    deform_inputs1,
                    deform_inputs2,
                    H_c,
                    W_c,
                    H_toks,
                    W_toks,
                )
            outs.append(x.transpose(1, 2).view(bs, dim, H_toks, W_toks).contiguous())

        # Split & Reshape
        c2 = c[:, 0 : c2.size(1), :]
        c3 = c[:, c2.size(1) : c2.size(1) + c3.size(1), :]
        c4 = c[:, c2.size(1) + c3.size(1) :, :]

        c2 = c2.transpose(1, 2).view(bs, dim, H_c * 2, W_c * 2).contiguous()
        c3 = c3.transpose(1, 2).view(bs, dim, H_c, W_c).contiguous()
        c4 = c4.transpose(1, 2).view(bs, dim, H_c // 2, W_c // 2).contiguous()
        c1 = self.up(c2) + c1

        if self.add_vit_feature:
            x1, x2, x3, x4 = outs

            x1 = F.interpolate(x1, size=(4 * H_c, 4 * W_c), mode="bilinear", align_corners=False)
            x2 = F.interpolate(x2, size=(2 * H_c, 2 * W_c), mode="bilinear", align_corners=False)
            x3 = F.interpolate(x3, size=(1 * H_c, 1 * W_c), mode="bilinear", align_corners=False)
            x4 = F.interpolate(x4, size=(H_c // 2, W_c // 2), mode="bilinear", align_corners=False)
            # print(c1.shape, c2.shape, c3.shape, c4.shape, x1.shape, x2.shape, x3.shape, x4.shape, H_c, H_toks)
            c1, c2, c3, c4 = c1 + x1, c2 + x2, c3 + x3, c4 + x4

        # Final Norm
        f1 = self.norm1(c1)
        f2 = self.norm2(c2)
        f3 = self.norm3(c3)
        f4 = self.norm4(c4)
        return [f1, f2, f3, f4]