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""" 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, is_pos_embed=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)
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