diff --git a/tests/test_models.py b/tests/test_models.py index b77b29ff66fcff7b3157db310e1812a9d71848a9..3013d0b98c554370703dc0996752534284d5ec93 100644 --- a/tests/test_models.py +++ b/tests/test_models.py @@ -15,7 +15,7 @@ if hasattr(torch._C, '_jit_set_profiling_executor'): torch._C._jit_set_profiling_mode(False) # transformer models don't support many of the spatial / feature based model functionalities -NON_STD_FILTERS = ['vit_*', 'tnt_*', 'pit_*', 'swin_*', 'coat_*', 'cait_*', '*mixer_*', 'gmlp_*', 'resmlp_*'] +NON_STD_FILTERS = ['vit_*', 'tnt_*', 'pit_*', 'swin_*', 'coat_*', 'cait_*', '*mixer_*', 'gmlp_*', 'resmlp_*', 'twins_*'] NUM_NON_STD = len(NON_STD_FILTERS) # exclude models that cause specific test failures diff --git a/timm/models/__init__.py b/timm/models/__init__.py index 46ea155f8607ae0a81f0c2d3a55642495c6d3b1b..293b459db6ab56e69348a98208bdf82fd9a390ae 100644 --- a/timm/models/__init__.py +++ b/timm/models/__init__.py @@ -39,6 +39,7 @@ from .vision_transformer_hybrid import * from .vovnet import * from .xception import * from .xception_aligned import * +from .twins import * from .factory import create_model, split_model_name, safe_model_name from .helpers import load_checkpoint, resume_checkpoint, model_parameters diff --git a/timm/models/twins.py b/timm/models/twins.py new file mode 100644 index 0000000000000000000000000000000000000000..a534d1740cedb8ea37ce17ba9b1dd2306dab79ad --- /dev/null +++ b/timm/models/twins.py @@ -0,0 +1,431 @@ +""" Twins +A PyTorch impl of : `Twins: Revisiting the Design of Spatial Attention in Vision Transformers` + - https://arxiv.org/pdf/2104.13840.pdf + +Code/weights from https://github.com/Meituan-AutoML/Twins, original copyright/license info below + +""" +# -------------------------------------------------------- +# Twins +# Copyright (c) 2021 Meituan +# Licensed under The Apache 2.0 License [see LICENSE for details] +# Written by Xinjie Li, Xiangxiang Chu +# -------------------------------------------------------- +import math +from copy import deepcopy +from typing import Optional, Tuple + +import torch +import torch.nn as nn +import torch.nn.functional as F +from functools import partial + +from timm.data import IMAGENET_DEFAULT_MEAN, IMAGENET_DEFAULT_STD +from .layers import Mlp, DropPath, to_2tuple, trunc_normal_ +from .registry import register_model +from .vision_transformer import Attention +from .helpers import build_model_with_cfg, overlay_external_default_cfg + + +def _cfg(url='', **kwargs): + return { + 'url': url, + 'num_classes': 1000, 'input_size': (3, 224, 224), 'pool_size': None, + 'crop_pct': .9, 'interpolation': 'bicubic', 'fixed_input_size': True, + 'mean': IMAGENET_DEFAULT_MEAN, 'std': IMAGENET_DEFAULT_STD, + 'first_conv': 'patch_embed.proj', 'classifier': 'head', + **kwargs + } + + +default_cfgs = { + 'twins_pcpvt_small': _cfg( + url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vt3p-weights/twins_pcpvt_small-e70e7e7a.pth', + ), + 'twins_pcpvt_base': _cfg( + url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vt3p-weights/twins_pcpvt_base-e5ecb09b.pth', + ), + 'twins_pcpvt_large': _cfg( + url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vt3p-weights/twins_pcpvt_large-d273f802.pth', + ), + 'twins_svt_small': _cfg( + url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vt3p-weights/twins_svt_small-42e5f78c.pth', + ), + 'twins_svt_base': _cfg( + url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vt3p-weights/twins_svt_base-c2265010.pth', + ), + 'twins_svt_large': _cfg( + url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-vt3p-weights/twins_svt_large-90f6aaa9.pth', + ), +} + +Size_ = Tuple[int, int] + + +class LocallyGroupedAttn(nn.Module): + """ LSA: self attention within a group + """ + def __init__(self, dim, num_heads=8, attn_drop=0., proj_drop=0., ws=1): + assert ws != 1 + super(LocallyGroupedAttn, self).__init__() + assert dim % num_heads == 0, f"dim {dim} should be divided by num_heads {num_heads}." + + self.dim = dim + self.num_heads = num_heads + head_dim = dim // num_heads + self.scale = head_dim ** -0.5 + + self.qkv = nn.Linear(dim, dim * 3, bias=True) + self.attn_drop = nn.Dropout(attn_drop) + self.proj = nn.Linear(dim, dim) + self.proj_drop = nn.Dropout(proj_drop) + self.ws = ws + + def forward(self, x, size: Size_): + # There are two implementations for this function, zero padding or mask. We don't observe obvious difference for + # both. You can choose any one, we recommend forward_padding because it's neat. However, + # the masking implementation is more reasonable and accurate. + B, N, C = x.shape + H, W = size + x = x.view(B, H, W, C) + pad_l = pad_t = 0 + pad_r = (self.ws - W % self.ws) % self.ws + pad_b = (self.ws - H % self.ws) % self.ws + x = F.pad(x, (0, 0, pad_l, pad_r, pad_t, pad_b)) + _, Hp, Wp, _ = x.shape + _h, _w = Hp // self.ws, Wp // self.ws + x = x.reshape(B, _h, self.ws, _w, self.ws, C).transpose(2, 3) + qkv = self.qkv(x).reshape( + B, _h * _w, self.ws * self.ws, 3, self.num_heads, C // self.num_heads).permute(3, 0, 1, 4, 2, 5) + q, k, v = qkv[0], qkv[1], qkv[2] + attn = (q @ k.transpose(-2, -1)) * self.scale + attn = attn.softmax(dim=-1) + attn = self.attn_drop(attn) + attn = (attn @ v).transpose(2, 3).reshape(B, _h, _w, self.ws, self.ws, C) + x = attn.transpose(2, 3).reshape(B, _h * self.ws, _w * self.ws, C) + if pad_r > 0 or pad_b > 0: + x = x[:, :H, :W, :].contiguous() + x = x.reshape(B, N, C) + x = self.proj(x) + x = self.proj_drop(x) + return x + + # def forward_mask(self, x, size: Size_): + # B, N, C = x.shape + # H, W = size + # x = x.view(B, H, W, C) + # pad_l = pad_t = 0 + # pad_r = (self.ws - W % self.ws) % self.ws + # pad_b = (self.ws - H % self.ws) % self.ws + # x = F.pad(x, (0, 0, pad_l, pad_r, pad_t, pad_b)) + # _, Hp, Wp, _ = x.shape + # _h, _w = Hp // self.ws, Wp // self.ws + # mask = torch.zeros((1, Hp, Wp), device=x.device) + # mask[:, -pad_b:, :].fill_(1) + # mask[:, :, -pad_r:].fill_(1) + # + # x = x.reshape(B, _h, self.ws, _w, self.ws, C).transpose(2, 3) # B, _h, _w, ws, ws, C + # mask = mask.reshape(1, _h, self.ws, _w, self.ws).transpose(2, 3).reshape(1, _h * _w, self.ws * self.ws) + # attn_mask = mask.unsqueeze(2) - mask.unsqueeze(3) # 1, _h*_w, ws*ws, ws*ws + # attn_mask = attn_mask.masked_fill(attn_mask != 0, float(-1000.0)).masked_fill(attn_mask == 0, float(0.0)) + # qkv = self.qkv(x).reshape( + # B, _h * _w, self.ws * self.ws, 3, self.num_heads, C // self.num_heads).permute(3, 0, 1, 4, 2, 5) + # # n_h, B, _w*_h, nhead, ws*ws, dim + # q, k, v = qkv[0], qkv[1], qkv[2] # B, _h*_w, n_head, ws*ws, dim_head + # attn = (q @ k.transpose(-2, -1)) * self.scale # B, _h*_w, n_head, ws*ws, ws*ws + # attn = attn + attn_mask.unsqueeze(2) + # attn = attn.softmax(dim=-1) + # attn = self.attn_drop(attn) # attn @v -> B, _h*_w, n_head, ws*ws, dim_head + # attn = (attn @ v).transpose(2, 3).reshape(B, _h, _w, self.ws, self.ws, C) + # x = attn.transpose(2, 3).reshape(B, _h * self.ws, _w * self.ws, C) + # if pad_r > 0 or pad_b > 0: + # x = x[:, :H, :W, :].contiguous() + # x = x.reshape(B, N, C) + # x = self.proj(x) + # x = self.proj_drop(x) + # return x + + +class GlobalSubSampleAttn(nn.Module): + """ GSA: using a key to summarize the information for a group to be efficient. + """ + def __init__(self, dim, num_heads=8, attn_drop=0., proj_drop=0., sr_ratio=1): + super().__init__() + assert dim % num_heads == 0, f"dim {dim} should be divided by num_heads {num_heads}." + + self.dim = dim + self.num_heads = num_heads + head_dim = dim // num_heads + self.scale = head_dim ** -0.5 + + self.q = nn.Linear(dim, dim, bias=True) + self.kv = nn.Linear(dim, dim * 2, bias=True) + self.attn_drop = nn.Dropout(attn_drop) + self.proj = nn.Linear(dim, dim) + self.proj_drop = nn.Dropout(proj_drop) + + self.sr_ratio = sr_ratio + if sr_ratio > 1: + self.sr = nn.Conv2d(dim, dim, kernel_size=sr_ratio, stride=sr_ratio) + self.norm = nn.LayerNorm(dim) + else: + self.sr = None + self.norm = None + + def forward(self, x, size: Size_): + B, N, C = x.shape + q = self.q(x).reshape(B, N, self.num_heads, C // self.num_heads).permute(0, 2, 1, 3) + + if self.sr is not None: + x = x.permute(0, 2, 1).reshape(B, C, *size) + x = self.sr(x).reshape(B, C, -1).permute(0, 2, 1) + x = self.norm(x) + kv = self.kv(x).reshape(B, -1, 2, self.num_heads, C // self.num_heads).permute(2, 0, 3, 1, 4) + k, v = kv[0], kv[1] + + attn = (q @ k.transpose(-2, -1)) * self.scale + attn = attn.softmax(dim=-1) + attn = self.attn_drop(attn) + + x = (attn @ v).transpose(1, 2).reshape(B, N, C) + x = self.proj(x) + x = self.proj_drop(x) + + return x + + +class Block(nn.Module): + + def __init__(self, dim, num_heads, mlp_ratio=4., drop=0., attn_drop=0., drop_path=0., + act_layer=nn.GELU, norm_layer=nn.LayerNorm, sr_ratio=1, ws=None): + super().__init__() + self.norm1 = norm_layer(dim) + if ws is None: + self.attn = Attention(dim, num_heads, False, None, attn_drop, drop) + elif ws == 1: + self.attn = GlobalSubSampleAttn(dim, num_heads, attn_drop, drop, sr_ratio) + else: + self.attn = LocallyGroupedAttn(dim, num_heads, attn_drop, drop, ws) + self.drop_path = DropPath(drop_path) if drop_path > 0. else nn.Identity() + self.norm2 = norm_layer(dim) + mlp_hidden_dim = int(dim * mlp_ratio) + self.mlp = Mlp(in_features=dim, hidden_features=mlp_hidden_dim, act_layer=act_layer, drop=drop) + + def forward(self, x, size: Size_): + x = x + self.drop_path(self.attn(self.norm1(x), size)) + x = x + self.drop_path(self.mlp(self.norm2(x))) + return x + + +class PosConv(nn.Module): + # PEG from https://arxiv.org/abs/2102.10882 + def __init__(self, in_chans, embed_dim=768, stride=1): + super(PosConv, self).__init__() + self.proj = nn.Sequential(nn.Conv2d(in_chans, embed_dim, 3, stride, 1, bias=True, groups=embed_dim), ) + self.stride = stride + + def forward(self, x, size: Size_): + B, N, C = x.shape + cnn_feat_token = x.transpose(1, 2).view(B, C, *size) + x = self.proj(cnn_feat_token) + if self.stride == 1: + x += cnn_feat_token + x = x.flatten(2).transpose(1, 2) + return x + + def no_weight_decay(self): + return ['proj.%d.weight' % i for i in range(4)] + + +class PatchEmbed(nn.Module): + """ Image to Patch Embedding + """ + + def __init__(self, img_size=224, patch_size=16, in_chans=3, embed_dim=768): + super().__init__() + img_size = to_2tuple(img_size) + patch_size = to_2tuple(patch_size) + + self.img_size = img_size + self.patch_size = patch_size + assert img_size[0] % patch_size[0] == 0 and img_size[1] % patch_size[1] == 0, \ + f"img_size {img_size} should be divided by patch_size {patch_size}." + self.H, self.W = img_size[0] // patch_size[0], img_size[1] // patch_size[1] + self.num_patches = self.H * self.W + self.proj = nn.Conv2d(in_chans, embed_dim, kernel_size=patch_size, stride=patch_size) + self.norm = nn.LayerNorm(embed_dim) + + def forward(self, x) -> Tuple[torch.Tensor, Size_]: + B, C, H, W = x.shape + + x = self.proj(x).flatten(2).transpose(1, 2) + x = self.norm(x) + out_size = (H // self.patch_size[0], W // self.patch_size[1]) + + return x, out_size + + +class Twins(nn.Module): + """ Twins Vision Transfomer (Revisiting Spatial Attention) + + Adapted from PVT (PyramidVisionTransformer) class at https://github.com/whai362/PVT.git + """ + def __init__( + self, img_size=224, patch_size=4, in_chans=3, num_classes=1000, embed_dims=(64, 128, 256, 512), + num_heads=(1, 2, 4, 8), mlp_ratios=(4, 4, 4, 4), drop_rate=0., attn_drop_rate=0., drop_path_rate=0., + norm_layer=partial(nn.LayerNorm, eps=1e-6), depths=(3, 4, 6, 3), sr_ratios=(8, 4, 2, 1), wss=None, + block_cls=Block): + super().__init__() + self.num_classes = num_classes + self.depths = depths + + img_size = to_2tuple(img_size) + prev_chs = in_chans + self.patch_embeds = nn.ModuleList() + self.pos_drops = nn.ModuleList() + for i in range(len(depths)): + self.patch_embeds.append(PatchEmbed(img_size, patch_size, prev_chs, embed_dims[i])) + self.pos_drops.append(nn.Dropout(p=drop_rate)) + prev_chs = embed_dims[i] + img_size = tuple(t // patch_size for t in img_size) + patch_size = 2 + + self.blocks = nn.ModuleList() + dpr = [x.item() for x in torch.linspace(0, drop_path_rate, sum(depths))] # stochastic depth decay rule + cur = 0 + for k in range(len(depths)): + _block = nn.ModuleList([block_cls( + dim=embed_dims[k], num_heads=num_heads[k], mlp_ratio=mlp_ratios[k], drop=drop_rate, + attn_drop=attn_drop_rate, drop_path=dpr[cur + i], norm_layer=norm_layer, sr_ratio=sr_ratios[k], + ws=1 if wss is None or i % 2 == 1 else wss[k]) for i in range(depths[k])]) + self.blocks.append(_block) + cur += depths[k] + + self.pos_block = nn.ModuleList([PosConv(embed_dim, embed_dim) for embed_dim in embed_dims]) + + self.norm = norm_layer(embed_dims[-1]) + + # classification head + self.head = nn.Linear(embed_dims[-1], num_classes) if num_classes > 0 else nn.Identity() + + # init weights + self.apply(self._init_weights) + + @torch.jit.ignore + def no_weight_decay(self): + return set(['pos_block.' + n for n, p in self.pos_block.named_parameters()]) + + def get_classifier(self): + return self.head + + 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() + + def _init_weights(self, m): + if isinstance(m, nn.Linear): + trunc_normal_(m.weight, std=.02) + if isinstance(m, nn.Linear) and m.bias is not None: + nn.init.constant_(m.bias, 0) + elif isinstance(m, nn.LayerNorm): + nn.init.constant_(m.bias, 0) + nn.init.constant_(m.weight, 1.0) + elif isinstance(m, nn.Conv2d): + fan_out = m.kernel_size[0] * m.kernel_size[1] * m.out_channels + fan_out //= m.groups + m.weight.data.normal_(0, math.sqrt(2.0 / fan_out)) + if m.bias is not None: + m.bias.data.zero_() + elif isinstance(m, nn.BatchNorm2d): + m.weight.data.fill_(1.0) + m.bias.data.zero_() + + def forward_features(self, x): + B = x.shape[0] + for i, (embed, drop, blocks, pos_blk) in enumerate( + zip(self.patch_embeds, self.pos_drops, self.blocks, self.pos_block)): + x, size = embed(x) + x = drop(x) + for j, blk in enumerate(blocks): + x = blk(x, size) + if j == 0: + x = pos_blk(x, size) # PEG here + if i < len(self.depths) - 1: + x = x.reshape(B, *size, -1).permute(0, 3, 1, 2).contiguous() + x = self.norm(x) + return x.mean(dim=1) # GAP here + + def forward(self, x): + x = self.forward_features(x) + x = self.head(x) + return x + + +def _create_twins(variant, pretrained=False, default_cfg=None, **kwargs): + if default_cfg is None: + 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) + if kwargs.get('features_only', None): + raise RuntimeError('features_only not implemented for Vision Transformer models.') + + model = build_model_with_cfg( + Twins, variant, pretrained, + default_cfg=default_cfg, + img_size=img_size, + num_classes=num_classes, + **kwargs) + + return model + + +@register_model +def twins_pcpvt_small(pretrained=False, **kwargs): + model_kwargs = dict( + patch_size=4, embed_dims=[64, 128, 320, 512], num_heads=[1, 2, 5, 8], mlp_ratios=[8, 8, 4, 4], + depths=[3, 4, 6, 3], sr_ratios=[8, 4, 2, 1], **kwargs) + return _create_twins('twins_pcpvt_small', pretrained=pretrained, **model_kwargs) + + +@register_model +def twins_pcpvt_base(pretrained=False, **kwargs): + model_kwargs = dict( + patch_size=4, embed_dims=[64, 128, 320, 512], num_heads=[1, 2, 5, 8], mlp_ratios=[8, 8, 4, 4], + depths=[3, 4, 18, 3], sr_ratios=[8, 4, 2, 1], **kwargs) + return _create_twins('twins_pcpvt_base', pretrained=pretrained, **model_kwargs) + + +@register_model +def twins_pcpvt_large(pretrained=False, **kwargs): + model_kwargs = dict( + patch_size=4, embed_dims=[64, 128, 320, 512], num_heads=[1, 2, 5, 8], mlp_ratios=[8, 8, 4, 4], + depths=[3, 8, 27, 3], sr_ratios=[8, 4, 2, 1], **kwargs) + return _create_twins('twins_pcpvt_large', pretrained=pretrained, **model_kwargs) + + +@register_model +def twins_svt_small(pretrained=False, **kwargs): + model_kwargs = dict( + patch_size=4, embed_dims=[64, 128, 256, 512], num_heads=[2, 4, 8, 16], mlp_ratios=[4, 4, 4, 4], + depths=[2, 2, 10, 4], wss=[7, 7, 7, 7], sr_ratios=[8, 4, 2, 1], **kwargs) + return _create_twins('twins_svt_small', pretrained=pretrained, **model_kwargs) + + +@register_model +def twins_svt_base(pretrained=False, **kwargs): + model_kwargs = dict( + patch_size=4, embed_dims=[96, 192, 384, 768], num_heads=[3, 6, 12, 24], mlp_ratios=[4, 4, 4, 4], + depths=[2, 2, 18, 2], wss=[7, 7, 7, 7], sr_ratios=[8, 4, 2, 1], **kwargs) + return _create_twins('twins_svt_base', pretrained=pretrained, **model_kwargs) + + +@register_model +def twins_svt_large(pretrained=False, **kwargs): + model_kwargs = dict( + patch_size=4, embed_dims=[128, 256, 512, 1024], num_heads=[4, 8, 16, 32], mlp_ratios=[4, 4, 4, 4], + depths=[2, 2, 18, 2], wss=[7, 7, 7, 7], sr_ratios=[8, 4, 2, 1], **kwargs) + return _create_twins('twins_svt_large', pretrained=pretrained, **model_kwargs)