File size: 30,165 Bytes
053d443 |
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 |
""" ViTamin
Paper: Designing Scalable Vison Models in the Vision-Language Era
@misc{chen2023designing,
title={Designing Scalable Vison Models in the Vision-Language Era},
author={Jieneng Chen and Qihang Yu and Xiaohui Shen and Alan Yuille and Liang-Cheih Chen},
year={2023},
archivePrefix={arXiv},
primaryClass={cs.CV}
}
Based on Apache 2.0 licensed code at https://github.com/ViTamin/ViTamin
Modifications and timm support by Jieneng Chen 2023
Adapted from timm codebase, thanks!
"""
from functools import partial
from typing import List, Tuple
from dataclasses import dataclass, replace
from typing import Callable, Optional, Union, Tuple, List, Sequence
import math, time
from torch.jit import Final
import torch
import torch.nn as nn
import torch.nn.functional as F
import timm
from torch.utils.checkpoint import checkpoint
from timm.models.layers import create_attn, get_norm_layer, get_norm_act_layer, create_conv2d, make_divisible, trunc_normal_tf_
from timm.layers import to_2tuple, DropPath, Format # , trunc_normal_
from timm.layers.norm_act import _create_act
from timm.models._registry import register_model
from timm.models._manipulate import named_apply, checkpoint_seq
from timm.models._builder import build_model_with_cfg
from timm.models.vision_transformer import get_act_layer, Type, LayerType, Mlp, Block, PatchEmbed, VisionTransformer, checkpoint_filter_fn, get_init_weights_vit, init_weights_vit_timm, _load_weights
import logging
from collections import OrderedDict
@dataclass
class VitConvCfg:
expand_ratio: float = 4.0
expand_output: bool = True # calculate expansion channels from output (vs input chs)
kernel_size: int = 3
group_size: int = 1 # 1 == depthwise
pre_norm_act: bool = False # activation after pre-norm
stride_mode: str = 'dw' # stride done via one of 'pool', '1x1', 'dw'
pool_type: str = 'avg2'
downsample_pool_type: str = 'avg2'
act_layer: str = 'gelu' # stem & stage 1234
norm_layer: str = ''
norm_layer_cl: str = ''
norm_eps: Optional[float] = None
down_shortcut: Optional[bool] = True
mlp: str = 'mlp'
def __post_init__(self):
use_mbconv = True
if not self.norm_layer:
self.norm_layer = 'batchnorm2d' if use_mbconv else 'layernorm2d'
if not self.norm_layer_cl and not use_mbconv:
self.norm_layer_cl = 'layernorm'
if self.norm_eps is None:
self.norm_eps = 1e-5 if use_mbconv else 1e-6
self.downsample_pool_type = self.downsample_pool_type or self.pool_type
@dataclass
class VitCfg:
embed_dim: Tuple[Union[int, Tuple[int, ...]], ...] = (96, 192, 384, 768)
depths: Tuple[Union[int, Tuple[int, ...]], ...] = (2, 3, 5, 2)
stem_width: int = 64
conv_cfg: VitConvCfg = VitConvCfg()
weight_init: str = 'vit_eff'
head_type: str = ""
stem_type: str = "stem"
def _init_conv(module, name, scheme=''):
if isinstance(module, nn.Conv2d):
fan_out = module.kernel_size[0] * module.kernel_size[1] * module.out_channels
fan_out //= module.groups
nn.init.normal_(module.weight, 0, math.sqrt(2.0 / fan_out))
if module.bias is not None:
nn.init.zeros_(module.bias)
class Stem(nn.Module):
def __init__(
self,
in_chs: int,
out_chs: int,
act_layer: str = 'gelu',
norm_layer: str = 'layernorm2d',
norm_eps: float = 1e-6,
bias: bool = True,
):
super().__init__()
self.grad_checkpointing=False
norm_act_layer = partial(get_norm_act_layer(norm_layer, act_layer), eps=norm_eps)
self.out_chs = out_chs
self.conv1 = create_conv2d(in_chs, out_chs, 3, stride=2, bias=bias)
self.norm1 = norm_act_layer(out_chs)
self.conv2 = create_conv2d(out_chs, out_chs, 3, stride=1, bias=bias)
named_apply(_init_conv, self)
def forward(self, x):
if self.grad_checkpointing:
x = checkpoint(self.conv1, x)
x = self.norm1(x)
x = checkpoint(self.conv2, x)
else:
x = self.conv1(x)
x = self.norm1(x)
x = self.conv2(x)
return x
class Downsample2d(nn.Module):
def __init__(
self,
dim: int,
dim_out: int,
bias: bool = True,
):
super().__init__()
self.pool = nn.AvgPool2d(kernel_size=3, stride=2, padding=1, count_include_pad=False)
if dim != dim_out:
self.expand = nn.Conv2d(dim, dim_out, 1, bias=bias) # 1x1 conv
else:
self.expand = nn.Identity()
def forward(self, x):
x = self.pool(x)
x = self.expand(x)
return x
class StridedConv(nn.Module):
""" downsample 2d as well
"""
def __init__(
self,
kernel_size=3,
stride=2,
padding=1,
in_chans=3,
embed_dim=768,
):
super().__init__()
self.proj = nn.Conv2d(in_chans, embed_dim, kernel_size=kernel_size, stride=stride, padding=padding)
norm_layer = partial(get_norm_layer('layernorm2d'), eps=1e-6)
self.norm = norm_layer(in_chans)
def forward(self, x):
x = self.norm(x)
x = self.proj(x)
return x
class MbConvLNBlock(nn.Module):
def __init__(
self,
in_chs: int,
out_chs: int,
stride: int = 1,
drop_path: float = 0.,
kernel_size: int = 3,
norm_layer: str = 'layernorm2d',
norm_eps: float = 1e-6,
act_layer: str = 'gelu',
expand_ratio: float = 4.0,
):
super(MbConvLNBlock, self).__init__()
self.stride, self.in_chs, self.out_chs = stride, in_chs, out_chs
mid_chs = make_divisible(out_chs * expand_ratio)
prenorm_act_layer = partial(get_norm_act_layer(norm_layer, act_layer), eps=norm_eps)
if stride == 2:
self.shortcut = Downsample2d(in_chs, out_chs, bias=True)
elif in_chs != out_chs:
self.shortcut = nn.Conv2d(in_chs, out_chs, 1, bias=True)
else:
self.shortcut = nn.Identity()
self.pre_norm = prenorm_act_layer(in_chs, apply_act=False)
self.down = nn.Identity()
self.conv1_1x1 = create_conv2d(in_chs, mid_chs, 1, stride=1, bias=True)
self.act1 = _create_act(act_layer, inplace=True)
self.act2 = _create_act(act_layer, inplace=True)
self.conv2_kxk = create_conv2d(mid_chs, mid_chs, kernel_size, stride=stride, dilation=1, groups=mid_chs, bias=True)
self.conv3_1x1 = create_conv2d(mid_chs, out_chs, 1, bias=True)
self.drop_path = DropPath(drop_path) if drop_path > 0. else nn.Identity()
def init_weights(self, scheme=''):
named_apply(partial(_init_conv, scheme=scheme), self)
def forward(self, x):
shortcut = self.shortcut(x)
x = self.pre_norm(x)
x = self.down(x) # nn.Identity()
# 1x1 expansion conv & act
x = self.conv1_1x1(x)
x = self.act1(x)
# (strided) depthwise 3x3 conv & act
x = self.conv2_kxk(x)
x = self.act2(x)
# 1x1 linear projection to output width
x = self.conv3_1x1(x)
x = self.drop_path(x) + shortcut
return x
class MbConvStages(nn.Module):
""" stage 1 and stage 2 of ViTamin: MBConv-LN blocks
"""
def __init__(
self,
cfg: VitCfg,
img_size: Union[int, Tuple[int, int]] = 224, # place holder
in_chans: int = 3,
):
super().__init__()
self.grad_checkpointing = False
self.stem = Stem(
in_chs=in_chans,
out_chs=cfg.stem_width,
)
stages = []
self.num_stages = len(cfg.embed_dim)
for s, dim in enumerate(cfg.embed_dim[:2]):
blocks = []
stage_in_chs = cfg.embed_dim[s-1] if s>0 else cfg.stem_width
for d in range(cfg.depths[s]):
blocks += [MbConvLNBlock(
in_chs = stage_in_chs if d==0 else dim,
out_chs = dim,
stride = 2 if d == 0 else 1,
)]
blocks = nn.Sequential(*blocks)
stages += [blocks]
self.stages = nn.ModuleList(stages)
self.pool = StridedConv(
stride=2,
in_chans=cfg.embed_dim[1],
embed_dim=cfg.embed_dim[2]
)
def forward(self, x):
x = self.stem(x)
if self.grad_checkpointing and not torch.jit.is_scripting():
for stage in self.stages:
x = checkpoint_seq(stage, x)
x = checkpoint(self.pool, x)
else:
for stage in self.stages:
x = stage(x)
x = self.pool(x)
return x
class GeGluMlp(nn.Module):
def __init__(
self,
in_features,
hidden_features,
act_layer = None,
drop = 0.0,
):
super().__init__()
norm_layer = partial(get_norm_layer('layernorm'), eps=1e-6)
self.norm = norm_layer(in_features)
self.act = nn.GELU()
self.w0 = nn.Linear(in_features, hidden_features)
self.w1 = nn.Linear(in_features, hidden_features)
self.w2 = nn.Linear(hidden_features, in_features)
def forward(self, x):
x = self.norm(x)
x = self.act(self.w0(x)) * self.w1(x)
x = self.w2(x)
return x
class HybridEmbed(nn.Module):
"""
Extract feature map from stage 1-2, flatten, project to embedding dim.
"""
def __init__(
self,
backbone,
img_size=224,
patch_size=1,
feature_size=None,
in_chans=3,
embed_dim=1024,
bias=True,
dynamic_img_pad=False,
):
super().__init__()
assert isinstance(backbone, nn.Module)
img_size = to_2tuple(img_size)
patch_size = to_2tuple(patch_size)
self.img_size = img_size
self.patch_size = patch_size
self.backbone = backbone
if feature_size is None:
feature_size = img_size[0] // 16
feature_size = to_2tuple(feature_size)
if hasattr(self.backbone, 'feature_info'):
feature_dim = self.backbone.feature_info.channels()[-1]
elif hasattr(self.backbone, 'num_features'):
feature_dim = self.backbone.num_features
else:
feature_dim = embed_dim
assert feature_size[0] % patch_size[0] == 0 and feature_size[1] % patch_size[1] == 0
self.grid_size = (feature_size[0] // patch_size[0], feature_size[1] // patch_size[1])
self.num_patches = self.grid_size[0] * self.grid_size[1]
self.proj = nn.Identity()
def forward(self, x):
x = self.backbone(x)
if isinstance(x, (list, tuple)):
x = x[-1] # last feature if backbone outputs list/tuple of features
x = self.proj(x)
x = x.flatten(2).transpose(1, 2)
return x
def _trunc_normal_(tensor, mean, std, a, b):
# rewrite timm trunc normal
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)
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_() # NOTE: deleted as "erfinv_cuda" not implemented for 'BFloat16'
# 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.):
with torch.no_grad():
return _trunc_normal_(tensor, mean, std, a, b)
class ViTamin(nn.Module):
""" hack timm VisionTransformer
"""
dynamic_img_size: Final[bool]
def __init__(
self,
img_size: Union[int, Tuple[int, int]] = 224,
patch_size: Union[int, Tuple[int, int]] = 16,
in_chans: int = 3,
num_classes: int = 1000,
global_pool = 'token',
embed_dim: int = 768,
depth: int = 12,
num_heads: int = 12,
mlp_ratio: float = 4.,
qkv_bias: bool = True,
qk_norm: bool = False,
init_values: Optional[float] = None,
class_token: bool = True,
no_embed_class: bool = False,
reg_tokens: int = 0,
pre_norm: bool = False,
fc_norm: Optional[bool] = None,
dynamic_img_size: bool = False,
dynamic_img_pad: bool = False,
drop_rate: float = 0.,
pos_drop_rate: float = 0.,
patch_drop_rate: float = 0.,
proj_drop_rate: float = 0.,
attn_drop_rate: float = 0.,
drop_path_rate: float = 0.,
weight_init = '',
fix_init: bool = False,
embed_layer: Callable = PatchEmbed,
norm_layer: Optional[LayerType] = None,
act_layer: Optional[LayerType] = None,
block_fn: Type[nn.Module] = Block,
mlp_layer: Type[nn.Module] = Mlp,
is_pos_embed: bool = True
) -> None:
"""
Args:
img_size: Input image size.
patch_size: Patch size.
in_chans: Number of image input channels.
num_classes: Mumber of classes for classification head.
global_pool: Type of global pooling for final sequence (default: 'token').
embed_dim: Transformer embedding dimension.
depth: Depth of transformer.
num_heads: Number of attention heads.
mlp_ratio: Ratio of mlp hidden dim to embedding dim.
qkv_bias: Enable bias for qkv projections if True.
init_values: Layer-scale init values (layer-scale enabled if not None).
class_token: Use class token.
no_embed_class: Don't include position embeddings for class (or reg) tokens.
reg_tokens: Number of register tokens.
fc_norm: Pre head norm after pool (instead of before), if None, enabled when global_pool == 'avg'.
drop_rate: Head dropout rate.
pos_drop_rate: Position embedding dropout rate.
attn_drop_rate: Attention dropout rate.
drop_path_rate: Stochastic depth rate.
weight_init: Weight initialization scheme.
fix_init: Apply weight initialization fix (scaling w/ layer index).
embed_layer: Patch embedding layer.
norm_layer: Normalization layer.
act_layer: MLP activation layer.
block_fn: Transformer block layer.
"""
super().__init__()
assert global_pool in ('', 'avg', 'token', 'map')
assert class_token or global_pool != 'token'
use_fc_norm = global_pool == 'avg' if fc_norm is None else fc_norm
norm_layer = get_norm_layer(norm_layer) or partial(nn.LayerNorm, eps=1e-6)
act_layer = get_act_layer(act_layer) or nn.GELU
self.num_classes = num_classes
self.global_pool = global_pool
self.num_features = self.embed_dim = embed_dim # num_features for consistency with other models
self.num_prefix_tokens = 1 if class_token else 0
self.num_prefix_tokens += reg_tokens
self.num_reg_tokens = reg_tokens
self.has_class_token = class_token
self.no_embed_class = no_embed_class # don't embed prefix positions (includes reg)
self.dynamic_img_size = dynamic_img_size
self.grad_checkpointing = False
self.is_pos_embed = is_pos_embed
embed_args = {}
if dynamic_img_size:
# flatten deferred until after pos embed
embed_args.update(dict(strict_img_size=False, output_fmt='NHWC'))
# stage_1_2 = MbConvStages(cfg=VitCfg(
# embed_dim=(160, 320, 1024),
# depths=(2, 4, 1),
# stem_width=160,
# conv_cfg = VitConvCfg(
# norm_layer='layernorm2d',
# norm_eps=1e-6,
# ),
# head_type='1d',
# ),
# )
# self.patch_embed = HybridEmbed(
# stage_1_2,
# img_size=img_size,
# patch_size=1,
# in_chans=in_chans,
# embed_dim=embed_dim,
# bias=not pre_norm,
# dynamic_img_pad=dynamic_img_pad,
# **embed_args,)
self.patch_embed = embed_layer(
img_size=img_size,
patch_size=patch_size,
in_chans=in_chans,
embed_dim=embed_dim,
bias=not pre_norm, # disable bias if pre-norm is used (e.g. CLIP)
)
num_patches = self.patch_embed.num_patches
self.cls_token = nn.Parameter(torch.zeros(1, 1, embed_dim)) if class_token else None
self.reg_token = nn.Parameter(torch.zeros(1, reg_tokens, embed_dim)) if reg_tokens else None
if self.is_pos_embed:
embed_len = num_patches if no_embed_class else num_patches + self.num_prefix_tokens
self.pos_embed = nn.Parameter(torch.randn(1, embed_len, embed_dim) * .02)
else:
self.pos_embed = None
self.pos_drop = nn.Dropout(p=pos_drop_rate)
if patch_drop_rate > 0:
self.patch_drop = PatchDropout(
patch_drop_rate,
num_prefix_tokens=self.num_prefix_tokens,
)
else:
self.patch_drop = nn.Identity()
self.norm_pre = norm_layer(embed_dim) if pre_norm else nn.Identity()
dpr = [x.item() for x in torch.linspace(0, drop_path_rate, depth)] # stochastic depth decay rule
self.blocks = nn.Sequential(*[
block_fn(
dim=embed_dim,
num_heads=num_heads,
mlp_ratio=mlp_ratio,
qkv_bias=qkv_bias,
qk_norm=qk_norm,
init_values=init_values,
proj_drop=proj_drop_rate,
attn_drop=attn_drop_rate,
drop_path=dpr[i],
norm_layer=norm_layer,
act_layer=act_layer,
mlp_layer=mlp_layer,
)
for i in range(depth)])
self.norm = norm_layer(embed_dim) if not use_fc_norm else nn.Identity()
# Classifier Head
if global_pool == 'map':
self.attn_pool = AttentionPoolLatent(
self.embed_dim,
num_heads=num_heads,
mlp_ratio=mlp_ratio,
norm_layer=norm_layer,
)
else:
self.attn_pool = None
self.fc_norm = norm_layer(embed_dim) if use_fc_norm else nn.Identity()
self.head_drop = nn.Dropout(drop_rate)
self.head = nn.Linear(self.embed_dim, num_classes) if num_classes > 0 else nn.Identity()
if weight_init != 'skip':
self.init_weights(weight_init)
if fix_init:
self.fix_init_weight()
def init_weights(self, mode=''):
assert mode in ('jax', 'jax_nlhb', 'moco', '')
head_bias = -math.log(self.num_classes) if 'nlhb' in mode else 0.
if self.is_pos_embed:
trunc_normal_(self.pos_embed, std=.02)
if self.cls_token is not None:
nn.init.normal_(self.cls_token, std=1e-6)
named_apply(get_init_weights_vit(mode, head_bias), self)
def _init_weights(self, m):
# this fn left here for compat with downstream users
init_weights_vit_timm(m)
@torch.jit.ignore()
def load_pretrained(self, checkpoint_path, prefix=''):
_load_weights(self, checkpoint_path, prefix)
@torch.jit.ignore
def no_weight_decay(self):
if self.is_pos_embed:
return {'pos_embed', 'cls_token', 'dist_token'}
else:
return {'cls_token', 'dist_token'}
@torch.jit.ignore
def group_matcher(self, coarse=False):
return dict(
stem=r'^cls_token|pos_embed|patch_embed', # stem and embed
blocks=[(r'^blocks\.(\d+)', None), (r'^norm', (99999,))]
)
@torch.jit.ignore
def set_grad_checkpointing(self, enable=True):
self.grad_checkpointing = enable
self.patch_embed.backbone.stem.grad_checkpointing = enable # disable https://blog.csdn.net/lhx526080338/article/details/127894671?utm_medium=distribute.pc_relevant.none-task-blog-2~default~baidujs_baidulandingword~default-1-127894671-blog-125562110.235^v38^pc_relevant_anti_t3_base&spm=1001.2101.3001.4242.2&utm_relevant_index=4
self.patch_embed.backbone.grad_checkpointing = enable
@torch.jit.ignore
def get_classifier(self):
return self.head
def reset_classifier(self, num_classes: int, global_pool=None):
self.num_classes = num_classes
if global_pool is not None:
assert global_pool in ('', 'avg', 'token')
self.global_pool = global_pool
self.head = nn.Linear(self.embed_dim, num_classes) if num_classes > 0 else nn.Identity()
def _pos_embed(self, x):
if self.no_embed_class:
# deit-3, updated JAX (big vision)
# position embedding does not overlap with class token, add then concat
x = x + self.pos_embed
if self.cls_token is not None:
x = torch.cat((self.cls_token.expand(x.shape[0], -1, -1), x), dim=1)
else:
# original timm, JAX, and deit vit impl
# pos_embed has entry for class token, concat then add
if self.cls_token is not None:
x = torch.cat((self.cls_token.expand(x.shape[0], -1, -1), x), dim=1)
x = x + self.pos_embed
return self.pos_drop(x)
def forward_features(self, x: torch.Tensor) -> torch.Tensor:
x = self.patch_embed(x)
if self.is_pos_embed:
x = self._pos_embed(x)
x = self.patch_drop(x)
x = self.norm_pre(x)
if self.grad_checkpointing and not torch.jit.is_scripting():
x = checkpoint_seq(self.blocks, x)
else:
x = self.blocks(x)
x = self.norm(x)
return x
def forward_head(self, x: torch.Tensor, pre_logits: bool = False) -> torch.Tensor:
if self.attn_pool is not None:
x = self.attn_pool(x)
elif self.global_pool == 'avg':
x = x[:, self.num_prefix_tokens:].mean(dim=1)
elif self.global_pool:
x = x[:, 0] # class token
x = self.fc_norm(x)
x = self.head_drop(x)
return x if pre_logits else self.head(x)
def forward(self, x: torch.Tensor) -> torch.Tensor:
x = self.forward_features(x)
x = self.forward_head(x)
return x
def _create_vision_transformer(variant, pretrained=False, **kwargs):
if kwargs.get('features_only', None):
raise RuntimeError('features_only not implemented for Vision Transformer models.')
return build_model_with_cfg(
ViTamin, # ViTamin
variant,
pretrained,
pretrained_filter_fn=checkpoint_filter_fn,
**kwargs,
)
def _create_vision_transformer_hybrid(variant, backbone, pretrained=False, **kwargs):
embed_layer = partial(HybridEmbed, backbone=backbone)
kwargs.setdefault('patch_size', 1) # default patch size for hybrid models if not set
return _create_vision_transformer(variant, pretrained=pretrained, embed_layer=embed_layer, **kwargs)
@register_model
def vitamin_small(pretrained=False, **kwargs) -> VisionTransformer:
stage_1_2 = MbConvStages(cfg=VitCfg(
embed_dim=(64, 128, 384),
depths=(2, 4, 1),
stem_width=64,
conv_cfg = VitConvCfg(
norm_layer='layernorm2d',
norm_eps=1e-6,
),
head_type='1d',
),
)
stage3_args = dict(embed_dim=384, depth=14, num_heads=6, mlp_layer=GeGluMlp, mlp_ratio=2., class_token=False, global_pool='avg')
model = _create_vision_transformer_hybrid('vitamin_small', backbone=stage_1_2, pretrained=pretrained, **dict(stage3_args, **kwargs))
return model
@register_model
def vitamin_base(pretrained=False, **kwargs) -> VisionTransformer:
stage_1_2 = MbConvStages(cfg=VitCfg(
embed_dim=(128, 256, 768),
depths=(2, 4, 1),
stem_width=128,
conv_cfg = VitConvCfg(
norm_layer='layernorm2d',
norm_eps=1e-6,
),
head_type='1d',
),
)
stage3_args = dict(embed_dim=768, depth=14, num_heads=12, mlp_layer=GeGluMlp, mlp_ratio=2., class_token=False, global_pool='avg')
model = _create_vision_transformer_hybrid('vitamin_base', backbone=stage_1_2, pretrained=pretrained, **dict(stage3_args, **kwargs))
return model
@register_model
def vitamin_large(pretrained=False, **kwargs) -> VisionTransformer:
stage_1_2 = MbConvStages(cfg=VitCfg(
embed_dim=(160, 320, 1024),
depths=(2, 4, 1),
stem_width=160,
conv_cfg = VitConvCfg(
norm_layer='layernorm2d',
norm_eps=1e-6,
),
head_type='1d',
),
)
stage3_args = dict(embed_dim=1024, depth=31, num_heads=16, mlp_layer=GeGluMlp, mlp_ratio=2., class_token=False, global_pool='avg')
model = _create_vision_transformer_hybrid(
'vitamin_large', backbone=stage_1_2, pretrained=pretrained, **dict(stage3_args, **kwargs))
return model
@register_model
def vitamin_large_256(pretrained=False, **kwargs) -> VisionTransformer:
backbone = MbConvStages(cfg=VitCfg(
embed_dim=(160, 320, 1024),
depths=(2, 4, 1),
stem_width=160,
conv_cfg = VitConvCfg(
norm_layer='layernorm2d',
norm_eps=1e-6,
),
head_type='1d',
),
)
model_args = dict(img_size=256, embed_dim=1024, depth=31, num_heads=16, mlp_layer=GeGluMlp, mlp_ratio=2., class_token=False, global_pool='avg')
model = _create_vision_transformer_hybrid(
'vitamin_large_256', backbone=backbone, pretrained=pretrained, **dict(model_args, **kwargs))
return model
@register_model
def vitamin_large_336(pretrained=False, **kwargs) -> VisionTransformer:
backbone = MbConvStages(cfg=VitCfg(
embed_dim=(160, 320, 1024),
depths=(2, 4, 1),
stem_width=160,
conv_cfg = VitConvCfg(
norm_layer='layernorm2d',
norm_eps=1e-6,
),
head_type='1d',
),
)
model_args = dict(img_size=336, embed_dim=1024, depth=31, num_heads=16, mlp_layer=GeGluMlp, mlp_ratio=2., class_token=False, global_pool='avg')
model = _create_vision_transformer_hybrid(
'vitamin_large_336', backbone=backbone, pretrained=pretrained, **dict(model_args, **kwargs))
return model
@register_model
def vitamin_large_384(pretrained=False, **kwargs) -> VisionTransformer:
backbone = MbConvStages(cfg=VitCfg(
embed_dim=(160, 320, 1024),
depths=(2, 4, 1),
stem_width=160,
conv_cfg = VitConvCfg(
norm_layer='layernorm2d',
norm_eps=1e-6,
),
head_type='1d',
),
)
model_args = dict(img_size=384, embed_dim=1024, depth=31, num_heads=16, mlp_layer=GeGluMlp, mlp_ratio=2., class_token=False, global_pool='avg')
model = _create_vision_transformer_hybrid(
'vitamin_large_384', backbone=backbone, pretrained=pretrained, **dict(model_args, **kwargs))
return model
@register_model
def vitamin_xlarge_256(pretrained=False, **kwargs) -> VisionTransformer:
backbone = MbConvStages(cfg=VitCfg(
embed_dim=(192, 384, 1152),
depths=(2, 4, 1),
stem_width=192,
conv_cfg = VitConvCfg(
norm_layer='layernorm2d',
norm_eps=1e-6,
),
head_type='1d',
),
)
model_args = dict(img_size=256, embed_dim=1152, depth=32, num_heads=16, mlp_layer=GeGluMlp, mlp_ratio=2., class_token=False, is_pos_embed=False, global_pool='avg')
model = _create_vision_transformer_hybrid(
'vitamin_xlarge_256', backbone=backbone, pretrained=pretrained, **dict(model_args, **kwargs))
return model
@register_model
def vitamin_xlarge_384(pretrained=False, **kwargs) -> VisionTransformer:
backbone = MbConvStages(cfg=VitCfg(
embed_dim=(192, 384, 1152),
depths=(2, 4, 1),
stem_width=192,
conv_cfg = VitConvCfg(
norm_layer='layernorm2d',
norm_eps=1e-6,
),
head_type='1d',
),
)
model_args = dict(img_size=384, embed_dim=1152, depth=32, num_heads=16, mlp_layer=GeGluMlp, mlp_ratio=2., class_token=False, is_pos_embed=False, global_pool='avg')
model = _create_vision_transformer_hybrid(
'vitamin_xlarge_384', backbone=backbone, pretrained=pretrained, **dict(model_args, **kwargs))
return model
def count_params(model: nn.Module):
return sum([m.numel() for m in model.parameters()])
def count_stage_params(model: nn.Module, prefix='none'):
collections = []
for name, m in model.named_parameters():
print(name)
if name.startswith(prefix):
collections.append(m.numel())
return sum(collections)
if __name__ == "__main__":
model = timm.create_model('vitamin_large', num_classes=10).cuda()
# x = torch.rand([2,3,224,224]).cuda()
check_keys(model)
|