-
Notifications
You must be signed in to change notification settings - Fork 4
/
dino_vits.py
488 lines (404 loc) · 17.8 KB
/
dino_vits.py
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
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
# Copyright (c) Facebook, Inc. and its affiliates.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
Copied from dino transformers and added the global pool layer
"""
import math
from functools import partial
import torch
import torch.nn as nn
def _no_grad_trunc_normal_(tensor, mean, std, a, b):
# Cut & paste from PyTorch official master until it's in a few official releases - RW
# Method based on https://people.sc.fsu.edu/~jburkardt/presentations/truncated_normal.pdf
def norm_cdf(x):
# Computes standard normal cumulative distribution function
return (1. + math.erf(x / math.sqrt(2.))) / 2.
if (mean < a - 2 * std) or (mean > b + 2 * std):
warnings.warn("mean is more than 2 std from [a, b] in nn.init.trunc_normal_. "
"The distribution of values may be incorrect.",
stacklevel=2)
with torch.no_grad():
# Values are generated by using a truncated uniform distribution and
# then using the inverse CDF for the normal distribution.
# Get upper and lower cdf values
l = norm_cdf((a - mean) / std)
u = norm_cdf((b - mean) / std)
# Uniformly fill tensor with values from [l, u], then translate to
# [2l-1, 2u-1].
tensor.uniform_(2 * l - 1, 2 * u - 1)
# Use inverse cdf transform for normal distribution to get truncated
# standard normal
tensor.erfinv_()
# Transform to proper mean, std
tensor.mul_(std * math.sqrt(2.))
tensor.add_(mean)
# Clamp to ensure it's in the proper range
tensor.clamp_(min=a, max=b)
return tensor
def trunc_normal_(tensor, mean=0., std=1., a=-2., b=2.):
# type: (Tensor, float, float, float, float) -> Tensor
return _no_grad_trunc_normal_(tensor, mean, std, a, b)
def drop_path(x, drop_prob: float = 0., training: bool = False):
if drop_prob == 0. or not training:
return x
keep_prob = 1 - drop_prob
shape = (x.shape[0],) + (1,) * (x.ndim - 1) # work with diff dim tensors, not just 2D ConvNets
random_tensor = keep_prob + torch.rand(shape, dtype=x.dtype, device=x.device)
random_tensor.floor_() # binarize
output = x.div(keep_prob) * random_tensor
return output
class DropPath(nn.Module):
"""Drop paths (Stochastic Depth) per sample (when applied in main path of residual blocks).
"""
def __init__(self, drop_prob=None):
super(DropPath, self).__init__()
self.drop_prob = drop_prob
def forward(self, x):
return drop_path(x, self.drop_prob, self.training)
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 Attention(nn.Module):
def __init__(self, dim, num_heads=8, qkv_bias=False, qk_scale=None, attn_drop=0., proj_drop=0.):
super().__init__()
self.num_heads = num_heads
head_dim = dim // num_heads
self.scale = qk_scale or head_dim ** -0.5
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)
def forward(self, x):
B, N, C = x.shape
qkv = self.qkv(x).reshape(B, N, 3, self.num_heads, C // self.num_heads).permute(2, 0, 3, 1, 4)
q, k, v = qkv[0], qkv[1], qkv[2]
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, attn
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):
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)
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, return_attention=False):
y, attn = self.attn(self.norm1(x))
if return_attention:
return attn
x = x + self.drop_path(y)
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__()
num_patches = (img_size // patch_size) * (img_size // patch_size)
self.img_size = img_size
self.patch_size = patch_size
self.num_patches = num_patches
self.proj = nn.Conv2d(in_chans, embed_dim, kernel_size=patch_size, stride=patch_size)
def forward(self, x):
B, C, H, W = x.shape
x = self.proj(x).flatten(2).transpose(1, 2)
return x
class VisionTransformer(nn.Module):
""" Vision Transformer """
def __init__(self, img_size=[224], patch_size=16, in_chans=3, num_classes=0, embed_dim=768, depth=12,
num_heads=12, mlp_ratio=4., qkv_bias=False, qk_scale=None, drop_rate=0., attn_drop_rate=0.,
drop_path_rate=0., norm_layer=nn.LayerNorm, global_pool='token',**kwargs):
super().__init__()
self.num_features = self.embed_dim = embed_dim
self.patch_embed = PatchEmbed(
img_size=img_size[0], 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.pos_embed = nn.Parameter(torch.zeros(1, num_patches + 1, embed_dim))
self.pos_drop = nn.Dropout(p=drop_rate)
dpr = [x.item() for x in torch.linspace(0, drop_path_rate, depth)] # stochastic depth decay rule
self.blocks = nn.ModuleList([
Block(
dim=embed_dim, num_heads=num_heads, mlp_ratio=mlp_ratio, qkv_bias=qkv_bias, qk_scale=qk_scale,
drop=drop_rate, attn_drop=attn_drop_rate, drop_path=dpr[i], norm_layer=norm_layer)
for i in range(depth)])
self.norm = norm_layer(embed_dim)
# Classifier head
self.head = nn.Linear(embed_dim, num_classes) if num_classes > 0 else nn.Identity()
trunc_normal_(self.pos_embed, std=.02)
trunc_normal_(self.cls_token, std=.02)
self.apply(self._init_weights)
self.global_pool = global_pool
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)
def interpolate_pos_encoding(self, x, w, h):
npatch = x.shape[1] - 1
N = self.pos_embed.shape[1] - 1
if npatch == N and w == h:
return self.pos_embed
class_pos_embed = self.pos_embed[:, 0]
patch_pos_embed = self.pos_embed[:, 1:]
dim = x.shape[-1]
w0 = w // self.patch_embed.patch_size
h0 = h // self.patch_embed.patch_size
# we add a small number to avoid floating point error in the interpolation
# see discussion at https://github.com/facebookresearch/dino/issues/8
w0, h0 = w0 + 0.1, h0 + 0.1
patch_pos_embed = nn.functional.interpolate(
patch_pos_embed.reshape(1, int(math.sqrt(N)), int(math.sqrt(N)), dim).permute(0, 3, 1, 2),
scale_factor=(w0 / math.sqrt(N), h0 / math.sqrt(N)),
mode='bicubic',
)
assert int(w0) == patch_pos_embed.shape[-2] and int(h0) == patch_pos_embed.shape[-1]
patch_pos_embed = patch_pos_embed.permute(0, 2, 3, 1).view(1, -1, dim)
return torch.cat((class_pos_embed.unsqueeze(0), patch_pos_embed), dim=1)
def prepare_tokens(self, x):
B, nc, w, h = x.shape
x = self.patch_embed(x) # patch linear embedding
# add the [CLS] token to the embed patch tokens
cls_tokens = self.cls_token.expand(B, -1, -1)
x = torch.cat((cls_tokens, x), dim=1)
# add positional encoding to each token
x = x + self.interpolate_pos_encoding(x, w, h)
return self.pos_drop(x)
def forward(self, x):
x = self.prepare_tokens(x)
for blk in self.blocks:
x = blk(x)
x = self.norm(x)
if self.global_pool == 'token':
return x[:, 0]
elif self.global_pool == '':
return x
def get_last_selfattention(self, x):
x = self.prepare_tokens(x)
for i, blk in enumerate(self.blocks):
if i < len(self.blocks) - 1:
x = blk(x)
else:
# return attention of the last block
return blk(x, return_attention=True)
def get_intermediate_layers(self, x, n=1):
x = self.prepare_tokens(x)
# we return the output tokens from the `n` last blocks
output = []
for i, blk in enumerate(self.blocks):
x = blk(x)
if len(self.blocks) - i <= n:
output.append(self.norm(x))
return output
def vit_tiny(patch_size=16, **kwargs):
model = VisionTransformer(
patch_size=patch_size, embed_dim=192, depth=12, num_heads=3, mlp_ratio=4,
qkv_bias=True, norm_layer=partial(nn.LayerNorm, eps=1e-6), **kwargs)
return model
def vit_small(patch_size=16, **kwargs):
model = VisionTransformer(
patch_size=patch_size, embed_dim=384, depth=12, num_heads=6, mlp_ratio=4,
qkv_bias=True, norm_layer=partial(nn.LayerNorm, eps=1e-6), **kwargs)
return model
def vit_base(patch_size=16, **kwargs):
model = VisionTransformer(
patch_size=patch_size, embed_dim=768, depth=12, num_heads=12, mlp_ratio=4,
qkv_bias=True, norm_layer=partial(nn.LayerNorm, eps=1e-6), **kwargs)
return model
class DINOHead(nn.Module):
def __init__(self, in_dim, out_dim, use_bn=False, norm_last_layer=True, nlayers=3, hidden_dim=2048, bottleneck_dim=256):
super().__init__()
nlayers = max(nlayers, 1)
if nlayers == 1:
self.mlp = nn.Linear(in_dim, bottleneck_dim)
else:
layers = [nn.Linear(in_dim, hidden_dim)]
if use_bn:
layers.append(nn.BatchNorm1d(hidden_dim))
layers.append(nn.GELU())
for _ in range(nlayers - 2):
layers.append(nn.Linear(hidden_dim, hidden_dim))
if use_bn:
layers.append(nn.BatchNorm1d(hidden_dim))
layers.append(nn.GELU())
layers.append(nn.Linear(hidden_dim, bottleneck_dim))
self.mlp = nn.Sequential(*layers)
self.apply(self._init_weights)
self.last_layer = nn.utils.weight_norm(nn.Linear(bottleneck_dim, out_dim, bias=False))
self.last_layer.weight_g.data.fill_(1)
if norm_last_layer:
self.last_layer.weight_g.requires_grad = False
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)
def forward(self, x):
x = self.mlp(x)
x = nn.functional.normalize(x, dim=-1, p=2)
x = self.last_layer(x)
return x
#### code from hubconf
def dino_vits16(pretrained=True, **kwargs):
"""
ViT-Small/16x16 pre-trained with DINO.
Achieves 74.5% top-1 accuracy on ImageNet with k-NN classification.
"""
model = vit_small(patch_size=16, num_classes=0, **kwargs)
if pretrained:
state_dict = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/dino/dino_deitsmall16_pretrain/dino_deitsmall16_pretrain.pth",
map_location="cpu",
)
model.load_state_dict(state_dict, strict=True)
return model
def dino_vits8(pretrained=True, **kwargs):
"""
ViT-Small/8x8 pre-trained with DINO.
Achieves 78.3% top-1 accuracy on ImageNet with k-NN classification.
"""
model = vit_small(patch_size=8, num_classes=0, **kwargs)
if pretrained:
state_dict = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/dino/dino_deitsmall8_pretrain/dino_deitsmall8_pretrain.pth",
map_location="cpu",
)
model.load_state_dict(state_dict, strict=True)
return model
def dino_vitb16(pretrained=True, **kwargs):
"""
ViT-Base/16x16 pre-trained with DINO.
Achieves 76.1% top-1 accuracy on ImageNet with k-NN classification.
"""
model = vit_base(patch_size=16, num_classes=0, **kwargs)
if pretrained:
state_dict = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/dino/dino_vitbase16_pretrain/dino_vitbase16_pretrain.pth",
map_location="cpu",
)
model.load_state_dict(state_dict, strict=True)
return model
def dino_vitb8(pretrained=True, **kwargs):
"""
ViT-Base/8x8 pre-trained with DINO.
Achieves 77.4% top-1 accuracy on ImageNet with k-NN classification.
"""
model = vit_base(patch_size=8, num_classes=0, **kwargs)
if pretrained:
state_dict = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/dino/dino_vitbase8_pretrain/dino_vitbase8_pretrain.pth",
map_location="cpu",
)
model.load_state_dict(state_dict, strict=True)
return model
def dino_vitb_cifar10(pretrained=True, **kwargs):
"""
ViT-Base/16x16 pre-trained with DINO.
Achieves 76.1% top-1 accuracy on ImageNet with k-NN classification.
"""
model = vit_base(patch_size=16, num_classes=0, **kwargs)
if pretrained:
state_dict = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/dino/cifar100_ViT_B_dino.pth",
map_location="cpu",
)
model.load_state_dict(state_dict, strict=False)
return model
def dino_resnet50(pretrained=True, **kwargs):
"""
ResNet-50 pre-trained with DINO.
Achieves 75.3% top-1 accuracy on ImageNet linear evaluation benchmark (requires to train `fc`).
"""
from torchvision.models.resnet import resnet50
model = resnet50(pretrained=False, **kwargs)
model.fc = torch.nn.Identity()
if pretrained:
state_dict = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/dino/dino_resnet50_pretrain/dino_resnet50_pretrain.pth",
map_location="cpu",
)
model.load_state_dict(state_dict, strict=False)
return model
def dino_xcit_small_12_p16(pretrained=True, **kwargs):
"""
XCiT-Small-12/16 pre-trained with DINO.
"""
model = torch.hub.load('facebookresearch/xcit:main', "xcit_small_12_p16", num_classes=0, **kwargs)
if pretrained:
state_dict = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/dino/dino_xcit_small_12_p16_pretrain/dino_xcit_small_12_p16_pretrain.pth",
map_location="cpu",
)
model.load_state_dict(state_dict, strict=True)
return model
def dino_xcit_small_12_p8(pretrained=True, **kwargs):
"""
XCiT-Small-12/8 pre-trained with DINO.
"""
model = torch.hub.load('facebookresearch/xcit:main', "xcit_small_12_p8", num_classes=0, **kwargs)
if pretrained:
state_dict = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/dino/dino_xcit_small_12_p8_pretrain/dino_xcit_small_12_p8_pretrain.pth",
map_location="cpu",
)
model.load_state_dict(state_dict, strict=True)
return model
def dino_xcit_medium_24_p16(pretrained=True, **kwargs):
"""
XCiT-Medium-24/16 pre-trained with DINO.
"""
model = torch.hub.load('facebookresearch/xcit:main', "xcit_medium_24_p16", num_classes=0, **kwargs)
if pretrained:
state_dict = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/dino/dino_xcit_medium_24_p16_pretrain/dino_xcit_medium_24_p16_pretrain.pth",
map_location="cpu",
)
model.load_state_dict(state_dict, strict=True)
return model
def dino_xcit_medium_24_p8(pretrained=True, **kwargs):
"""
XCiT-Medium-24/8 pre-trained with DINO.
"""
model = torch.hub.load('facebookresearch/xcit:main', "xcit_medium_24_p8", num_classes=0, **kwargs)
if pretrained:
state_dict = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/dino/dino_xcit_medium_24_p8_pretrain/dino_xcit_medium_24_p8_pretrain.pth",
map_location="cpu",
)
model.load_state_dict(state_dict, strict=True)
return model