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813 lines
37 KiB
813 lines
37 KiB
""" Vision Transformer (ViT) in PyTorch
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A PyTorch implement of Vision Transformers as described in
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'An Image Is Worth 16 x 16 Words: Transformers for Image Recognition at Scale' - https://arxiv.org/abs/2010.11929
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The official jax code is released and available at https://github.com/google-research/vision_transformer
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Acknowledgments:
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* The paper authors for releasing code and weights, thanks!
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* I fixed my class token impl based on Phil Wang's https://github.com/lucidrains/vit-pytorch ... check it out
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for some einops/einsum fun
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* Simple transformer style inspired by Andrej Karpathy's https://github.com/karpathy/minGPT
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* Bert reference code checks against Huggingface Transformers and Tensorflow Bert
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DeiT model defs and weights from https://github.com/facebookresearch/deit,
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paper `DeiT: Data-efficient Image Transformers` - https://arxiv.org/abs/2012.12877
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Hacked together by / Copyright 2020 Ross Wightman
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"""
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import math
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import logging
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from functools import partial
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from collections import OrderedDict
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from copy import deepcopy
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import torch
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import torch.nn as nn
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import torch.nn.functional as F
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from timm.data import IMAGENET_DEFAULT_MEAN, IMAGENET_DEFAULT_STD
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from .helpers import build_model_with_cfg, overlay_external_default_cfg
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from .layers import DropPath, to_2tuple, trunc_normal_, lecun_normal_
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from .registry import register_model
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_logger = logging.getLogger(__name__)
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def _cfg(url='', **kwargs):
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return {
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'url': url,
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'num_classes': 1000, 'input_size': (3, 224, 224), 'pool_size': None,
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'crop_pct': .9, 'interpolation': 'bicubic',
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'mean': IMAGENET_DEFAULT_MEAN, 'std': IMAGENET_DEFAULT_STD,
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'first_conv': 'patch_embed.proj', 'classifier': 'head',
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**kwargs
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}
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default_cfgs = {
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# patch models (my experiments)
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'vit_small_patch16_224': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-weights/vit_small_p16_224-15ec54c9.pth',
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),
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# patch models (weights ported from official Google JAX impl)
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'vit_base_patch16_224': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vitjx/jx_vit_base_p16_224-80ecf9dd.pth',
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mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5),
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),
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'vit_base_patch32_224': _cfg(
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url='', # no official model weights for this combo, only for in21k
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mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5)),
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'vit_base_patch16_384': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vitjx/jx_vit_base_p16_384-83fb41ba.pth',
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input_size=(3, 384, 384), mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5), crop_pct=1.0),
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'vit_base_patch32_384': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vitjx/jx_vit_base_p32_384-830016f5.pth',
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input_size=(3, 384, 384), mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5), crop_pct=1.0),
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'vit_large_patch16_224': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vitjx/jx_vit_large_p16_224-4ee7a4dc.pth',
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mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5)),
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'vit_large_patch32_224': _cfg(
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url='', # no official model weights for this combo, only for in21k
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mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5)),
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'vit_large_patch16_384': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vitjx/jx_vit_large_p16_384-b3be5167.pth',
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input_size=(3, 384, 384), mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5), crop_pct=1.0),
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'vit_large_patch32_384': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vitjx/jx_vit_large_p32_384-9b920ba8.pth',
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input_size=(3, 384, 384), mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5), crop_pct=1.0),
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# patch models, imagenet21k (weights ported from official Google JAX impl)
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'vit_base_patch16_224_in21k': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vitjx/jx_vit_base_patch16_224_in21k-e5005f0a.pth',
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num_classes=21843, mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5)),
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'vit_base_patch32_224_in21k': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vitjx/jx_vit_base_patch32_224_in21k-8db57226.pth',
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num_classes=21843, mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5)),
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'vit_large_patch16_224_in21k': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vitjx/jx_vit_large_patch16_224_in21k-606da67d.pth',
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num_classes=21843, mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5)),
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'vit_large_patch32_224_in21k': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vitjx/jx_vit_large_patch32_224_in21k-9046d2e7.pth',
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num_classes=21843, mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5)),
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'vit_huge_patch14_224_in21k': _cfg(
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hf_hub='timm/vit_huge_patch14_224_in21k',
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num_classes=21843, mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5)),
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# deit models (FB weights)
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'vit_deit_tiny_patch16_224': _cfg(
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url='https://dl.fbaipublicfiles.com/deit/deit_tiny_patch16_224-a1311bcf.pth'),
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'vit_deit_tiny_patch16_224_in21k': _cfg(num_classes=21843),
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'vit_deit_tiny_patch16_384': _cfg(input_size=(3, 384, 384)),
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'vit_deit_small_patch16_224': _cfg(
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url='https://dl.fbaipublicfiles.com/deit/deit_small_patch16_224-cd65a155.pth'),
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'vit_deit_small_patch16_224_in21k': _cfg(num_classes=21843),
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'vit_deit_small_patch16_384': _cfg(input_size=(3, 384, 384)),
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'vit_deit_small_patch32_224': _cfg(),
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'vit_deit_small_patch32_224_in21k': _cfg(num_classes=21843),
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'vit_deit_small_patch32_384': _cfg(input_size=(3, 384, 384)),
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'vit_deit_base_patch16_224': _cfg(
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url='https://dl.fbaipublicfiles.com/deit/deit_base_patch16_224-b5f2ef4d.pth',),
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'vit_deit_base_patch16_384': _cfg(
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url='https://dl.fbaipublicfiles.com/deit/deit_base_patch16_384-8de9b5d1.pth',
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input_size=(3, 384, 384), crop_pct=1.0),
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'vit_deit_tiny_distilled_patch16_224': _cfg(
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url='https://dl.fbaipublicfiles.com/deit/deit_tiny_distilled_patch16_224-b40b3cf7.pth',
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classifier=('head', 'head_dist')),
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'vit_deit_small_distilled_patch16_224': _cfg(
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url='https://dl.fbaipublicfiles.com/deit/deit_small_distilled_patch16_224-649709d9.pth',
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classifier=('head', 'head_dist')),
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'vit_deit_base_distilled_patch16_224': _cfg(
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url='https://dl.fbaipublicfiles.com/deit/deit_base_distilled_patch16_224-df68dfff.pth',
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classifier=('head', 'head_dist')),
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'vit_deit_base_distilled_patch16_384': _cfg(
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url='https://dl.fbaipublicfiles.com/deit/deit_base_distilled_patch16_384-d0272ac0.pth',
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input_size=(3, 384, 384), crop_pct=1.0, classifier=('head', 'head_dist')),
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}
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class Mlp(nn.Module):
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def __init__(self, in_features, hidden_features=None, out_features=None, act_layer=nn.GELU, drop=0.):
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super().__init__()
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out_features = out_features or in_features
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hidden_features = hidden_features or in_features
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self.fc1 = nn.Linear(in_features, hidden_features)
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self.act = act_layer()
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self.fc2 = nn.Linear(hidden_features, out_features)
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self.drop = nn.Dropout(drop)
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def forward(self, x):
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x = self.fc1(x)
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x = self.act(x)
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x = self.drop(x)
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x = self.fc2(x)
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x = self.drop(x)
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return x
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class Attention(nn.Module):
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def __init__(self, dim, num_heads=8, qkv_bias=False, qk_scale=None, attn_drop=0., proj_drop=0.):
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super().__init__()
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self.num_heads = num_heads
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head_dim = dim // num_heads
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self.scale = qk_scale or head_dim ** -0.5
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self.qkv = nn.Linear(dim, dim * 3, bias=qkv_bias)
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self.attn_drop = nn.Dropout(attn_drop)
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self.proj = nn.Linear(dim, dim)
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self.proj_drop = nn.Dropout(proj_drop)
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def forward(self, x):
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B, N, C = x.shape
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qkv = self.qkv(x).reshape(B, N, 3, self.num_heads, C // self.num_heads).permute(2, 0, 3, 1, 4)
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q, k, v = qkv[0], qkv[1], qkv[2] # make torchscript happy (cannot use tensor as tuple)
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attn = (q @ k.transpose(-2, -1)) * self.scale
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attn = attn.softmax(dim=-1)
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attn = self.attn_drop(attn)
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x = (attn @ v).transpose(1, 2).reshape(B, N, C)
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x = self.proj(x)
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x = self.proj_drop(x)
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return x
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class Block(nn.Module):
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def __init__(self, dim, num_heads, mlp_ratio=4., qkv_bias=False, qk_scale=None, drop=0., attn_drop=0.,
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drop_path=0., act_layer=nn.GELU, norm_layer=nn.LayerNorm):
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super().__init__()
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self.norm1 = norm_layer(dim)
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self.attn = Attention(
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dim, num_heads=num_heads, qkv_bias=qkv_bias, qk_scale=qk_scale, attn_drop=attn_drop, proj_drop=drop)
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# NOTE: drop path for stochastic depth, we shall see if this is better than dropout here
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self.drop_path = DropPath(drop_path) if drop_path > 0. else nn.Identity()
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self.norm2 = norm_layer(dim)
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mlp_hidden_dim = int(dim * mlp_ratio)
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self.mlp = Mlp(in_features=dim, hidden_features=mlp_hidden_dim, act_layer=act_layer, drop=drop)
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def forward(self, x):
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x = x + self.drop_path(self.attn(self.norm1(x)))
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x = x + self.drop_path(self.mlp(self.norm2(x)))
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return x
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class PatchEmbed(nn.Module):
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""" Image to Patch Embedding
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"""
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def __init__(self, img_size=224, patch_size=16, in_chans=3, embed_dim=768):
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super().__init__()
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img_size = to_2tuple(img_size)
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patch_size = to_2tuple(patch_size)
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num_patches = (img_size[1] // patch_size[1]) * (img_size[0] // patch_size[0])
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self.img_size = img_size
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self.patch_size = patch_size
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self.num_patches = num_patches
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self.proj = nn.Conv2d(in_chans, embed_dim, kernel_size=patch_size, stride=patch_size)
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def forward(self, x):
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B, C, H, W = x.shape
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# FIXME look at relaxing size constraints
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assert H == self.img_size[0] and W == self.img_size[1], \
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f"Input image size ({H}*{W}) doesn't match model ({self.img_size[0]}*{self.img_size[1]})."
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x = self.proj(x).flatten(2).transpose(1, 2)
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return x
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class HybridEmbed(nn.Module):
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""" CNN Feature Map Embedding
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Extract feature map from CNN, flatten, project to embedding dim.
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"""
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def __init__(self, backbone, img_size=224, patch_size=1, feature_size=None, in_chans=3, embed_dim=768):
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super().__init__()
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assert isinstance(backbone, nn.Module)
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img_size = to_2tuple(img_size)
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patch_size = to_2tuple(patch_size)
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self.img_size = img_size
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self.patch_size = patch_size
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self.backbone = backbone
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if feature_size is None:
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with torch.no_grad():
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# NOTE Most reliable way of determining output dims is to run forward pass
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training = backbone.training
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if training:
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backbone.eval()
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o = self.backbone(torch.zeros(1, in_chans, img_size[0], img_size[1]))
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if isinstance(o, (list, tuple)):
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o = o[-1] # last feature if backbone outputs list/tuple of features
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feature_size = o.shape[-2:]
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feature_dim = o.shape[1]
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backbone.train(training)
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else:
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feature_size = to_2tuple(feature_size)
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if hasattr(self.backbone, 'feature_info'):
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feature_dim = self.backbone.feature_info.channels()[-1]
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else:
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feature_dim = self.backbone.num_features
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assert feature_size[0] % patch_size[0] == 0 and feature_size[1] % patch_size[1] == 0
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self.num_patches = feature_size[0] // patch_size[0] * feature_size[1] // patch_size[1]
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self.proj = nn.Conv2d(feature_dim, embed_dim, kernel_size=patch_size, stride=patch_size)
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def forward(self, x):
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x = self.backbone(x)
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if isinstance(x, (list, tuple)):
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x = x[-1] # last feature if backbone outputs list/tuple of features
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x = self.proj(x).flatten(2).transpose(1, 2)
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return x
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class VisionTransformer(nn.Module):
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""" Vision Transformer
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A PyTorch impl of : `An Image is Worth 16x16 Words: Transformers for Image Recognition at Scale`
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- https://arxiv.org/abs/2010.11929
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Includes distillation token & head support for `DeiT: Data-efficient Image Transformers`
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- https://arxiv.org/abs/2012.12877
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"""
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def __init__(self, img_size=224, patch_size=16, in_chans=3, num_classes=1000, embed_dim=768, depth=12,
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num_heads=12, mlp_ratio=4., qkv_bias=True, qk_scale=None, representation_size=None, distilled=False,
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drop_rate=0., attn_drop_rate=0., drop_path_rate=0., hybrid_backbone=None, norm_layer=None,
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act_layer=None, weight_init=''):
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"""
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Args:
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img_size (int, tuple): input image size
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patch_size (int, tuple): patch size
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in_chans (int): number of input channels
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num_classes (int): number of classes for classification head
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embed_dim (int): embedding dimension
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depth (int): depth of transformer
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num_heads (int): number of attention heads
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mlp_ratio (int): ratio of mlp hidden dim to embedding dim
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qkv_bias (bool): enable bias for qkv if True
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qk_scale (float): override default qk scale of head_dim ** -0.5 if set
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representation_size (Optional[int]): enable and set representation layer (pre-logits) to this value if set
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distilled (bool): model includes a distillation token and head as in DeiT models
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drop_rate (float): dropout rate
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attn_drop_rate (float): attention dropout rate
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drop_path_rate (float): stochastic depth rate
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hybrid_backbone (nn.Module): CNN backbone to use in-place of PatchEmbed module
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norm_layer: (nn.Module): normalization layer
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weight_init: (str): weight init scheme
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"""
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super().__init__()
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self.num_classes = num_classes
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self.num_features = self.embed_dim = embed_dim # num_features for consistency with other models
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self.num_tokens = 2 if distilled else 1
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norm_layer = norm_layer or partial(nn.LayerNorm, eps=1e-6)
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act_layer = act_layer or nn.GELU
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patch_size = patch_size or (1 if hybrid_backbone is not None else 16)
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if hybrid_backbone is not None:
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self.patch_embed = HybridEmbed(
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hybrid_backbone, img_size=img_size, patch_size=patch_size, in_chans=in_chans, embed_dim=embed_dim)
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else:
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self.patch_embed = PatchEmbed(
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img_size=img_size, patch_size=patch_size, in_chans=in_chans, embed_dim=embed_dim)
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num_patches = self.patch_embed.num_patches
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self.cls_token = nn.Parameter(torch.zeros(1, 1, embed_dim))
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self.dist_token = nn.Parameter(torch.zeros(1, 1, embed_dim)) if distilled else None
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self.pos_embed = nn.Parameter(torch.zeros(1, num_patches + self.num_tokens, embed_dim))
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self.pos_drop = nn.Dropout(p=drop_rate)
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dpr = [x.item() for x in torch.linspace(0, drop_path_rate, depth)] # stochastic depth decay rule
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self.blocks = nn.Sequential(*[
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Block(
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dim=embed_dim, num_heads=num_heads, mlp_ratio=mlp_ratio, qkv_bias=qkv_bias, qk_scale=qk_scale,
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drop=drop_rate, attn_drop=attn_drop_rate, drop_path=dpr[i], norm_layer=norm_layer, act_layer=act_layer)
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for i in range(depth)])
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self.norm = norm_layer(embed_dim)
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# Representation layer
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if representation_size and not distilled:
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self.num_features = representation_size
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self.pre_logits = nn.Sequential(OrderedDict([
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('fc', nn.Linear(embed_dim, representation_size)),
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('act', nn.Tanh())
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]))
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else:
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self.pre_logits = nn.Identity()
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# Classifier head(s)
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self.head = nn.Linear(self.num_features, num_classes) if num_classes > 0 else nn.Identity()
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self.head_dist = nn.Linear(self.embed_dim, self.num_classes) \
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if num_classes > 0 and distilled else nn.Identity()
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# Weight init
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assert weight_init in ('jax', 'jax_nlhb', 'nlhb', '')
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head_bias = -math.log(self.num_classes) if 'nlhb' in weight_init else 0.
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trunc_normal_(self.pos_embed, std=.02)
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if weight_init.startswith('jax'):
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# leave cls token as zeros to match jax impl
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for n, m in self.named_modules():
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_init_weights_jax(m, n, head_bias=head_bias)
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else:
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trunc_normal_(self.cls_token, std=.02)
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if self.dist_token is not None:
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trunc_normal_(self.dist_token, std=.02)
|
|
for n, m in self.named_modules():
|
|
self._init_weights(m, n, head_bias=head_bias)
|
|
|
|
def _init_weights(self, m, n: str = '', head_bias: float = 0., init_conv=False):
|
|
# This impl does not exactly match the official JAX version.
|
|
# When called w/o n, head_bias, init_conv args it will behave exactly the same
|
|
# as my original init for compatibility with downstream use cases (ie DeiT).
|
|
if isinstance(m, nn.Linear):
|
|
if n.startswith('head'):
|
|
nn.init.zeros_(m.weight)
|
|
nn.init.constant_(m.bias, head_bias)
|
|
elif n.startswith('pre_logits'):
|
|
lecun_normal_(m.weight)
|
|
nn.init.zeros_(m.bias)
|
|
else:
|
|
trunc_normal_(m.weight, std=.02)
|
|
if m.bias is not None:
|
|
nn.init.zeros_(m.bias)
|
|
elif init_conv and isinstance(m, nn.Conv2d):
|
|
# NOTE conv was left to pytorch default init originally
|
|
lecun_normal_(m.weight)
|
|
if m.bias is not None:
|
|
nn.init.zeros_(m.bias)
|
|
elif isinstance(m, nn.LayerNorm):
|
|
nn.init.zeros_(m.bias)
|
|
nn.init.ones_(m.weight)
|
|
|
|
@torch.jit.ignore
|
|
def no_weight_decay(self):
|
|
return {'pos_embed', 'cls_token', 'dist_token'}
|
|
|
|
def get_classifier(self):
|
|
if self.dist_token is None:
|
|
return self.head
|
|
else:
|
|
return self.head, self.head_dist
|
|
|
|
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()
|
|
self.head_dist = nn.Linear(self.embed_dim, self.num_classes) \
|
|
if num_classes > 0 and self.dist_token is not None else nn.Identity()
|
|
|
|
def forward_features(self, x):
|
|
x = self.patch_embed(x)
|
|
cls_token = self.cls_token.expand(x.shape[0], -1, -1) # stole cls_tokens impl from Phil Wang, thanks
|
|
if self.dist_token is None:
|
|
x = torch.cat((cls_token, x), dim=1)
|
|
else:
|
|
x = torch.cat((cls_token, self.dist_token.expand(x.shape[0], -1, -1), x), dim=1)
|
|
x = self.pos_drop(x + self.pos_embed)
|
|
x = self.blocks(x)
|
|
x = self.norm(x)
|
|
if self.dist_token is None:
|
|
return self.pre_logits(x[:, 0])
|
|
else:
|
|
return x[:, 0], x[:, 1]
|
|
|
|
def forward(self, x):
|
|
x = self.forward_features(x)
|
|
if isinstance(x, tuple):
|
|
x, x_dist = self.head(x[0]), self.head_dist(x[1])
|
|
if self.training and not torch.jit.is_scripting():
|
|
# during inference, return the average of both classifier predictions
|
|
return x, x_dist
|
|
else:
|
|
return (x + x_dist) / 2
|
|
else:
|
|
x = self.head(x)
|
|
return x
|
|
|
|
|
|
def _init_weights_jax(m: nn.Module, n: str, head_bias: float = 0.):
|
|
# A weight init scheme closer to the official JAX impl than my original init
|
|
# NOTE: requires module name so cannot be used via module.apply()
|
|
if isinstance(m, nn.Linear):
|
|
if n.startswith('head'):
|
|
nn.init.zeros_(m.weight)
|
|
nn.init.constant_(m.bias, head_bias)
|
|
elif n.startswith('pre_logits'):
|
|
lecun_normal_(m.weight)
|
|
nn.init.zeros_(m.bias)
|
|
else:
|
|
nn.init.xavier_uniform_(m.weight)
|
|
if m.bias is not None:
|
|
if 'mlp' in n:
|
|
nn.init.normal_(m.bias, 0, 1e-6)
|
|
else:
|
|
nn.init.zeros_(m.bias)
|
|
elif isinstance(m, nn.Conv2d):
|
|
lecun_normal_(m.weight)
|
|
if m.bias is not None:
|
|
nn.init.zeros_(m.bias)
|
|
elif isinstance(m, nn.LayerNorm):
|
|
nn.init.zeros_(m.bias)
|
|
nn.init.ones_(m.weight)
|
|
|
|
|
|
def resize_pos_embed(posemb, posemb_new, num_tokens=1):
|
|
# Rescale the grid of position embeddings when loading from state_dict. Adapted from
|
|
# https://github.com/google-research/vision_transformer/blob/00883dd691c63a6830751563748663526e811cee/vit_jax/checkpoint.py#L224
|
|
_logger.info('Resized position embedding: %s to %s', posemb.shape, posemb_new.shape)
|
|
ntok_new = posemb_new.shape[1]
|
|
if num_tokens:
|
|
posemb_tok, posemb_grid = posemb[:, :num_tokens], posemb[0, num_tokens:]
|
|
ntok_new -= num_tokens
|
|
else:
|
|
posemb_tok, posemb_grid = posemb[:, :0], posemb[0]
|
|
gs_old = int(math.sqrt(len(posemb_grid)))
|
|
gs_new = int(math.sqrt(ntok_new))
|
|
_logger.info('Position embedding grid-size from %s to %s', gs_old, gs_new)
|
|
posemb_grid = posemb_grid.reshape(1, gs_old, gs_old, -1).permute(0, 3, 1, 2)
|
|
posemb_grid = F.interpolate(posemb_grid, size=(gs_new, gs_new), mode='bilinear')
|
|
posemb_grid = posemb_grid.permute(0, 2, 3, 1).reshape(1, gs_new * gs_new, -1)
|
|
posemb = torch.cat([posemb_tok, posemb_grid], dim=1)
|
|
return posemb
|
|
|
|
|
|
def checkpoint_filter_fn(state_dict, model):
|
|
""" convert patch embedding weight from manual patchify + linear proj to conv"""
|
|
out_dict = {}
|
|
if 'model' in state_dict:
|
|
# For deit models
|
|
state_dict = state_dict['model']
|
|
for k, v in state_dict.items():
|
|
if 'patch_embed.proj.weight' in k and len(v.shape) < 4:
|
|
# For old models that I trained prior to conv based patchification
|
|
O, I, H, W = model.patch_embed.proj.weight.shape
|
|
v = v.reshape(O, -1, H, W)
|
|
elif k == 'pos_embed' and v.shape != model.pos_embed.shape:
|
|
# To resize pos embedding when using model at different size from pretrained weights
|
|
v = resize_pos_embed(v, model.pos_embed, getattr(model, 'num_tokens', 1))
|
|
out_dict[k] = v
|
|
return out_dict
|
|
|
|
|
|
def _create_vision_transformer(variant, pretrained=False, **kwargs):
|
|
default_cfg = deepcopy(default_cfgs[variant])
|
|
overlay_external_default_cfg(default_cfg, kwargs)
|
|
default_num_classes = default_cfg['num_classes']
|
|
default_img_size = default_cfg['input_size'][-2:]
|
|
|
|
num_classes = kwargs.pop('num_classes', default_num_classes)
|
|
img_size = kwargs.pop('img_size', default_img_size)
|
|
repr_size = kwargs.pop('representation_size', None)
|
|
if repr_size is not None and num_classes != default_num_classes:
|
|
# Remove representation layer if fine-tuning. This may not always be the desired action,
|
|
# but I feel better than doing nothing by default for fine-tuning. Perhaps a better interface?
|
|
_logger.warning("Removing representation layer for fine-tuning.")
|
|
repr_size = None
|
|
|
|
if kwargs.get('features_only', None):
|
|
raise RuntimeError('features_only not implemented for Vision Transformer models.')
|
|
|
|
model = build_model_with_cfg(
|
|
VisionTransformer, variant, pretrained,
|
|
default_cfg=default_cfg,
|
|
img_size=img_size,
|
|
num_classes=num_classes,
|
|
representation_size=repr_size,
|
|
pretrained_filter_fn=checkpoint_filter_fn,
|
|
**kwargs)
|
|
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_small_patch16_224(pretrained=False, **kwargs):
|
|
""" My custom 'small' ViT model. embed_dim=768, depth=8, num_heads=8, mlp_ratio=3.
|
|
NOTE:
|
|
* this differs from the DeiT based 'small' definitions with embed_dim=384, depth=12, num_heads=6
|
|
* this model does not have a bias for QKV (unlike the official ViT and DeiT models)
|
|
"""
|
|
model_kwargs = dict(
|
|
patch_size=16, embed_dim=768, depth=8, num_heads=8, mlp_ratio=3.,
|
|
qkv_bias=False, norm_layer=nn.LayerNorm, **kwargs)
|
|
if pretrained:
|
|
# NOTE my scale was wrong for original weights, leaving this here until I have better ones for this model
|
|
model_kwargs.setdefault('qk_scale', 768 ** -0.5)
|
|
model = _create_vision_transformer('vit_small_patch16_224', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_base_patch16_224(pretrained=False, **kwargs):
|
|
""" ViT-Base (ViT-B/16) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-1k weights fine-tuned from in21k @ 224x224, source https://github.com/google-research/vision_transformer.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=768, depth=12, num_heads=12, **kwargs)
|
|
model = _create_vision_transformer('vit_base_patch16_224', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_base_patch32_224(pretrained=False, **kwargs):
|
|
""" ViT-Base (ViT-B/32) from original paper (https://arxiv.org/abs/2010.11929). No pretrained weights.
|
|
"""
|
|
model_kwargs = dict(patch_size=32, embed_dim=768, depth=12, num_heads=12, **kwargs)
|
|
model = _create_vision_transformer('vit_base_patch32_224', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_base_patch16_384(pretrained=False, **kwargs):
|
|
""" ViT-Base model (ViT-B/16) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-1k weights fine-tuned from in21k @ 384x384, source https://github.com/google-research/vision_transformer.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=768, depth=12, num_heads=12, **kwargs)
|
|
model = _create_vision_transformer('vit_base_patch16_384', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_base_patch32_384(pretrained=False, **kwargs):
|
|
""" ViT-Base model (ViT-B/32) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-1k weights fine-tuned from in21k @ 384x384, source https://github.com/google-research/vision_transformer.
|
|
"""
|
|
model_kwargs = dict(patch_size=32, embed_dim=768, depth=12, num_heads=12, **kwargs)
|
|
model = _create_vision_transformer('vit_base_patch32_384', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_large_patch16_224(pretrained=False, **kwargs):
|
|
""" ViT-Large model (ViT-L/32) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-1k weights fine-tuned from in21k @ 224x224, source https://github.com/google-research/vision_transformer.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=1024, depth=24, num_heads=16, **kwargs)
|
|
model = _create_vision_transformer('vit_large_patch16_224', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_large_patch32_224(pretrained=False, **kwargs):
|
|
""" ViT-Large model (ViT-L/32) from original paper (https://arxiv.org/abs/2010.11929). No pretrained weights.
|
|
"""
|
|
model_kwargs = dict(patch_size=32, embed_dim=1024, depth=24, num_heads=16, **kwargs)
|
|
model = _create_vision_transformer('vit_large_patch32_224', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_large_patch16_384(pretrained=False, **kwargs):
|
|
""" ViT-Large model (ViT-L/16) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-1k weights fine-tuned from in21k @ 384x384, source https://github.com/google-research/vision_transformer.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=1024, depth=24, num_heads=16, **kwargs)
|
|
model = _create_vision_transformer('vit_large_patch16_384', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_large_patch32_384(pretrained=False, **kwargs):
|
|
""" ViT-Large model (ViT-L/32) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-1k weights fine-tuned from in21k @ 384x384, source https://github.com/google-research/vision_transformer.
|
|
"""
|
|
model_kwargs = dict(patch_size=32, embed_dim=1024, depth=24, num_heads=16, **kwargs)
|
|
model = _create_vision_transformer('vit_large_patch32_384', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_base_patch16_224_in21k(pretrained=False, **kwargs):
|
|
""" ViT-Base model (ViT-B/16) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-21k weights @ 224x224, source https://github.com/google-research/vision_transformer.
|
|
"""
|
|
model_kwargs = dict(
|
|
patch_size=16, embed_dim=768, depth=12, num_heads=12, representation_size=768, **kwargs)
|
|
model = _create_vision_transformer('vit_base_patch16_224_in21k', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_base_patch32_224_in21k(pretrained=False, **kwargs):
|
|
""" ViT-Base model (ViT-B/32) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-21k weights @ 224x224, source https://github.com/google-research/vision_transformer.
|
|
"""
|
|
model_kwargs = dict(
|
|
patch_size=32, embed_dim=768, depth=12, num_heads=12, representation_size=768, **kwargs)
|
|
model = _create_vision_transformer('vit_base_patch32_224_in21k', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_large_patch16_224_in21k(pretrained=False, **kwargs):
|
|
""" ViT-Large model (ViT-L/16) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-21k weights @ 224x224, source https://github.com/google-research/vision_transformer.
|
|
"""
|
|
model_kwargs = dict(
|
|
patch_size=16, embed_dim=1024, depth=24, num_heads=16, representation_size=1024, **kwargs)
|
|
model = _create_vision_transformer('vit_large_patch16_224_in21k', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_large_patch32_224_in21k(pretrained=False, **kwargs):
|
|
""" ViT-Large model (ViT-L/32) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-21k weights @ 224x224, source https://github.com/google-research/vision_transformer.
|
|
"""
|
|
model_kwargs = dict(
|
|
patch_size=32, embed_dim=1024, depth=24, num_heads=16, representation_size=1024, **kwargs)
|
|
model = _create_vision_transformer('vit_large_patch32_224_in21k', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_huge_patch14_224_in21k(pretrained=False, **kwargs):
|
|
""" ViT-Huge model (ViT-H/14) from original paper (https://arxiv.org/abs/2010.11929).
|
|
ImageNet-21k weights @ 224x224, source https://github.com/google-research/vision_transformer.
|
|
NOTE: converted weights not currently available, too large for github release hosting.
|
|
"""
|
|
model_kwargs = dict(
|
|
patch_size=14, embed_dim=1280, depth=32, num_heads=16, representation_size=1280, **kwargs)
|
|
model = _create_vision_transformer('vit_huge_patch14_224_in21k', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_tiny_patch16_224(pretrained=False, **kwargs):
|
|
""" DeiT-tiny model @ 224x224 from paper (https://arxiv.org/abs/2012.12877).
|
|
ImageNet-1k weights from https://github.com/facebookresearch/deit.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=192, depth=12, num_heads=3, **kwargs)
|
|
model = _create_vision_transformer('vit_deit_tiny_patch16_224', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_tiny_patch16_224_in21k(pretrained=False, **kwargs):
|
|
""" DeiT-tiny model"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=192, depth=12, num_heads=3, representation_size=192, **kwargs)
|
|
model = _create_vision_transformer('vit_deit_tiny_patch16_224_in21k', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_tiny_patch16_384(pretrained=False, **kwargs):
|
|
""" DeiT-tiny model"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=192, depth=12, num_heads=3, **kwargs)
|
|
model = _create_vision_transformer('vit_deit_tiny_patch16_384', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_small_patch16_224(pretrained=False, **kwargs):
|
|
""" DeiT-small model @ 224x224 from paper (https://arxiv.org/abs/2012.12877).
|
|
ImageNet-1k weights from https://github.com/facebookresearch/deit.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=384, depth=12, num_heads=6, **kwargs)
|
|
model = _create_vision_transformer('vit_deit_small_patch16_224', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_small_patch16_224_in21k(pretrained=False, **kwargs):
|
|
""" DeiT-small """
|
|
model_kwargs = dict(patch_size=16, embed_dim=384, depth=12, num_heads=6, representation_size=384, **kwargs)
|
|
model = _create_vision_transformer('vit_deit_small_patch16_224_in21k', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_small_patch16_384(pretrained=False, **kwargs):
|
|
""" DeiT-small """
|
|
model_kwargs = dict(patch_size=16, embed_dim=384, depth=12, num_heads=6, **kwargs)
|
|
model = _create_vision_transformer('vit_deit_small_patch16_384', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_small_patch32_224(pretrained=False, **kwargs):
|
|
""" DeiT-small model @ 224x224 from paper (https://arxiv.org/abs/2012.12877).
|
|
ImageNet-1k weights from https://github.com/facebookresearch/deit.
|
|
"""
|
|
model_kwargs = dict(patch_size=32, embed_dim=384, depth=12, num_heads=6, **kwargs)
|
|
model = _create_vision_transformer('vit_deit_small_patch32_224', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_small_patch32_224_in21k(pretrained=False, **kwargs):
|
|
""" DeiT-small """
|
|
model_kwargs = dict(patch_size=32, embed_dim=384, depth=12, num_heads=6, representation_size=384, **kwargs)
|
|
model = _create_vision_transformer('vit_deit_small_patch32_224_in21k', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_small_patch32_384(pretrained=False, **kwargs):
|
|
""" DeiT-small """
|
|
model_kwargs = dict(patch_size=32, embed_dim=384, depth=12, num_heads=6, **kwargs)
|
|
model = _create_vision_transformer('vit_deit_small_patch32_384', pretrained=pretrained, **model_kwargs)
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return model
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@register_model
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def vit_deit_base_patch16_224(pretrained=False, **kwargs):
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""" DeiT base model @ 224x224 from paper (https://arxiv.org/abs/2012.12877).
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|
ImageNet-1k weights from https://github.com/facebookresearch/deit.
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|
"""
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model_kwargs = dict(patch_size=16, embed_dim=768, depth=12, num_heads=12, **kwargs)
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model = _create_vision_transformer('vit_deit_base_patch16_224', pretrained=pretrained, **model_kwargs)
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return model
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|
|
|
|
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@register_model
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|
def vit_deit_base_patch16_384(pretrained=False, **kwargs):
|
|
""" DeiT base model @ 384x384 from paper (https://arxiv.org/abs/2012.12877).
|
|
ImageNet-1k weights from https://github.com/facebookresearch/deit.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=768, depth=12, num_heads=12, **kwargs)
|
|
model = _create_vision_transformer('vit_deit_base_patch16_384', pretrained=pretrained, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_tiny_distilled_patch16_224(pretrained=False, **kwargs):
|
|
""" DeiT-tiny distilled model @ 224x224 from paper (https://arxiv.org/abs/2012.12877).
|
|
ImageNet-1k weights from https://github.com/facebookresearch/deit.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=192, depth=12, num_heads=3, **kwargs)
|
|
model = _create_vision_transformer(
|
|
'vit_deit_tiny_distilled_patch16_224', pretrained=pretrained, distilled=True, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_small_distilled_patch16_224(pretrained=False, **kwargs):
|
|
""" DeiT-small distilled model @ 224x224 from paper (https://arxiv.org/abs/2012.12877).
|
|
ImageNet-1k weights from https://github.com/facebookresearch/deit.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=384, depth=12, num_heads=6, **kwargs)
|
|
model = _create_vision_transformer(
|
|
'vit_deit_small_distilled_patch16_224', pretrained=pretrained, distilled=True, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_base_distilled_patch16_224(pretrained=False, **kwargs):
|
|
""" DeiT-base distilled model @ 224x224 from paper (https://arxiv.org/abs/2012.12877).
|
|
ImageNet-1k weights from https://github.com/facebookresearch/deit.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=768, depth=12, num_heads=12, **kwargs)
|
|
model = _create_vision_transformer(
|
|
'vit_deit_base_distilled_patch16_224', pretrained=pretrained, distilled=True, **model_kwargs)
|
|
return model
|
|
|
|
|
|
@register_model
|
|
def vit_deit_base_distilled_patch16_384(pretrained=False, **kwargs):
|
|
""" DeiT-base distilled model @ 384x384 from paper (https://arxiv.org/abs/2012.12877).
|
|
ImageNet-1k weights from https://github.com/facebookresearch/deit.
|
|
"""
|
|
model_kwargs = dict(patch_size=16, embed_dim=768, depth=12, num_heads=12, **kwargs)
|
|
model = _create_vision_transformer(
|
|
'vit_deit_base_distilled_patch16_384', pretrained=pretrained, distilled=True, **model_kwargs)
|
|
return model
|