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""" EfficientFormer-V2 |
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@article{ |
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li2022rethinking, |
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title={Rethinking Vision Transformers for MobileNet Size and Speed}, |
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author={Li, Yanyu and Hu, Ju and Wen, Yang and Evangelidis, Georgios and Salahi, Kamyar and Wang, Yanzhi and Tulyakov, Sergey and Ren, Jian}, |
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journal={arXiv preprint arXiv:2212.08059}, |
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year={2022} |
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} |
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Significantly refactored and cleaned up for timm from original at: https://github.com/snap-research/EfficientFormer |
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Original code licensed Apache 2.0, Copyright (c) 2022 Snap Inc. |
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Modifications and timm support by / Copyright 2023, Ross Wightman |
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""" |
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import math |
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from functools import partial |
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from typing import Dict |
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import torch |
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import torch.nn as nn |
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from timm.data import IMAGENET_DEFAULT_MEAN, IMAGENET_DEFAULT_STD |
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from timm.layers import create_conv2d, create_norm_layer, get_act_layer, get_norm_layer, ConvNormAct |
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from timm.layers import DropPath, trunc_normal_, to_2tuple, to_ntuple, ndgrid |
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from ._builder import build_model_with_cfg |
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from ._manipulate import checkpoint_seq |
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from ._registry import generate_default_cfgs, register_model |
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EfficientFormer_width = { |
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'L': (40, 80, 192, 384), |
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'S2': (32, 64, 144, 288), |
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'S1': (32, 48, 120, 224), |
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'S0': (32, 48, 96, 176), |
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} |
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EfficientFormer_depth = { |
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'L': (5, 5, 15, 10), |
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'S2': (4, 4, 12, 8), |
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'S1': (3, 3, 9, 6), |
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'S0': (2, 2, 6, 4), |
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} |
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EfficientFormer_expansion_ratios = { |
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'L': (4, 4, (4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4), (4, 4, 4, 3, 3, 3, 3, 4, 4, 4)), |
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'S2': (4, 4, (4, 4, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4), (4, 4, 3, 3, 3, 3, 4, 4)), |
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'S1': (4, 4, (4, 4, 3, 3, 3, 3, 4, 4, 4), (4, 4, 3, 3, 4, 4)), |
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'S0': (4, 4, (4, 3, 3, 3, 4, 4), (4, 3, 3, 4)), |
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} |
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class ConvNorm(nn.Module): |
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def __init__( |
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self, |
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in_channels, |
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out_channels, |
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kernel_size=1, |
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stride=1, |
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padding='', |
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dilation=1, |
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groups=1, |
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bias=True, |
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norm_layer='batchnorm2d', |
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norm_kwargs=None, |
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): |
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norm_kwargs = norm_kwargs or {} |
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super(ConvNorm, self).__init__() |
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self.conv = create_conv2d( |
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in_channels, |
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out_channels, |
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kernel_size, |
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stride=stride, |
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padding=padding, |
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dilation=dilation, |
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groups=groups, |
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bias=bias, |
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) |
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self.bn = create_norm_layer(norm_layer, out_channels, **norm_kwargs) |
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def forward(self, x): |
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x = self.conv(x) |
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x = self.bn(x) |
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return x |
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class Attention2d(torch.nn.Module): |
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attention_bias_cache: Dict[str, torch.Tensor] |
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def __init__( |
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self, |
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dim=384, |
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key_dim=32, |
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num_heads=8, |
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attn_ratio=4, |
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resolution=7, |
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act_layer=nn.GELU, |
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stride=None, |
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): |
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super().__init__() |
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self.num_heads = num_heads |
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self.scale = key_dim ** -0.5 |
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self.key_dim = key_dim |
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resolution = to_2tuple(resolution) |
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if stride is not None: |
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resolution = tuple([math.ceil(r / stride) for r in resolution]) |
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self.stride_conv = ConvNorm(dim, dim, kernel_size=3, stride=stride, groups=dim) |
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self.upsample = nn.Upsample(scale_factor=stride, mode='bilinear') |
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else: |
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self.stride_conv = None |
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self.upsample = None |
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self.resolution = resolution |
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self.N = self.resolution[0] * self.resolution[1] |
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self.d = int(attn_ratio * key_dim) |
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self.dh = int(attn_ratio * key_dim) * num_heads |
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self.attn_ratio = attn_ratio |
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kh = self.key_dim * self.num_heads |
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self.q = ConvNorm(dim, kh) |
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self.k = ConvNorm(dim, kh) |
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self.v = ConvNorm(dim, self.dh) |
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self.v_local = ConvNorm(self.dh, self.dh, kernel_size=3, groups=self.dh) |
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self.talking_head1 = nn.Conv2d(self.num_heads, self.num_heads, kernel_size=1) |
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self.talking_head2 = nn.Conv2d(self.num_heads, self.num_heads, kernel_size=1) |
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self.act = act_layer() |
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self.proj = ConvNorm(self.dh, dim, 1) |
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pos = torch.stack(ndgrid(torch.arange(self.resolution[0]), torch.arange(self.resolution[1]))).flatten(1) |
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rel_pos = (pos[..., :, None] - pos[..., None, :]).abs() |
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rel_pos = (rel_pos[0] * self.resolution[1]) + rel_pos[1] |
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self.attention_biases = torch.nn.Parameter(torch.zeros(num_heads, self.N)) |
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self.register_buffer('attention_bias_idxs', torch.LongTensor(rel_pos), persistent=False) |
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self.attention_bias_cache = {} |
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@torch.no_grad() |
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def train(self, mode=True): |
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super().train(mode) |
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if mode and self.attention_bias_cache: |
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self.attention_bias_cache = {} |
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def get_attention_biases(self, device: torch.device) -> torch.Tensor: |
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if torch.jit.is_tracing() or self.training: |
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return self.attention_biases[:, self.attention_bias_idxs] |
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else: |
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device_key = str(device) |
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if device_key not in self.attention_bias_cache: |
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self.attention_bias_cache[device_key] = self.attention_biases[:, self.attention_bias_idxs] |
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return self.attention_bias_cache[device_key] |
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def forward(self, x): |
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B, C, H, W = x.shape |
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if self.stride_conv is not None: |
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x = self.stride_conv(x) |
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q = self.q(x).reshape(B, self.num_heads, -1, self.N).permute(0, 1, 3, 2) |
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k = self.k(x).reshape(B, self.num_heads, -1, self.N).permute(0, 1, 2, 3) |
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v = self.v(x) |
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v_local = self.v_local(v) |
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v = v.reshape(B, self.num_heads, -1, self.N).permute(0, 1, 3, 2) |
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attn = (q @ k) * self.scale |
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attn = attn + self.get_attention_biases(x.device) |
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attn = self.talking_head1(attn) |
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attn = attn.softmax(dim=-1) |
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attn = self.talking_head2(attn) |
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x = (attn @ v).transpose(2, 3) |
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x = x.reshape(B, self.dh, self.resolution[0], self.resolution[1]) + v_local |
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if self.upsample is not None: |
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x = self.upsample(x) |
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x = self.act(x) |
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x = self.proj(x) |
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return x |
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class LocalGlobalQuery(torch.nn.Module): |
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def __init__(self, in_dim, out_dim): |
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super().__init__() |
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self.pool = nn.AvgPool2d(1, 2, 0) |
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self.local = nn.Conv2d(in_dim, in_dim, kernel_size=3, stride=2, padding=1, groups=in_dim) |
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self.proj = ConvNorm(in_dim, out_dim, 1) |
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def forward(self, x): |
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local_q = self.local(x) |
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pool_q = self.pool(x) |
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q = local_q + pool_q |
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q = self.proj(q) |
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return q |
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class Attention2dDownsample(torch.nn.Module): |
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attention_bias_cache: Dict[str, torch.Tensor] |
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def __init__( |
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self, |
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dim=384, |
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key_dim=16, |
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num_heads=8, |
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attn_ratio=4, |
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resolution=7, |
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out_dim=None, |
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act_layer=nn.GELU, |
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): |
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super().__init__() |
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self.num_heads = num_heads |
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self.scale = key_dim ** -0.5 |
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self.key_dim = key_dim |
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self.resolution = to_2tuple(resolution) |
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self.resolution2 = tuple([math.ceil(r / 2) for r in self.resolution]) |
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self.N = self.resolution[0] * self.resolution[1] |
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self.N2 = self.resolution2[0] * self.resolution2[1] |
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self.d = int(attn_ratio * key_dim) |
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self.dh = int(attn_ratio * key_dim) * num_heads |
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self.attn_ratio = attn_ratio |
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self.out_dim = out_dim or dim |
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kh = self.key_dim * self.num_heads |
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self.q = LocalGlobalQuery(dim, kh) |
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self.k = ConvNorm(dim, kh, 1) |
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self.v = ConvNorm(dim, self.dh, 1) |
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self.v_local = ConvNorm(self.dh, self.dh, kernel_size=3, stride=2, groups=self.dh) |
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self.act = act_layer() |
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self.proj = ConvNorm(self.dh, self.out_dim, 1) |
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self.attention_biases = nn.Parameter(torch.zeros(num_heads, self.N)) |
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k_pos = torch.stack(ndgrid(torch.arange(self.resolution[0]), torch.arange(self.resolution[1]))).flatten(1) |
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q_pos = torch.stack(ndgrid( |
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torch.arange(0, self.resolution[0], step=2), |
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torch.arange(0, self.resolution[1], step=2) |
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)).flatten(1) |
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rel_pos = (q_pos[..., :, None] - k_pos[..., None, :]).abs() |
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rel_pos = (rel_pos[0] * self.resolution[1]) + rel_pos[1] |
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self.register_buffer('attention_bias_idxs', rel_pos, persistent=False) |
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self.attention_bias_cache = {} |
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@torch.no_grad() |
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def train(self, mode=True): |
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super().train(mode) |
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if mode and self.attention_bias_cache: |
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self.attention_bias_cache = {} |
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def get_attention_biases(self, device: torch.device) -> torch.Tensor: |
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if torch.jit.is_tracing() or self.training: |
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return self.attention_biases[:, self.attention_bias_idxs] |
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else: |
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device_key = str(device) |
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if device_key not in self.attention_bias_cache: |
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self.attention_bias_cache[device_key] = self.attention_biases[:, self.attention_bias_idxs] |
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return self.attention_bias_cache[device_key] |
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def forward(self, x): |
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B, C, H, W = x.shape |
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q = self.q(x).reshape(B, self.num_heads, -1, self.N2).permute(0, 1, 3, 2) |
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k = self.k(x).reshape(B, self.num_heads, -1, self.N).permute(0, 1, 2, 3) |
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v = self.v(x) |
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v_local = self.v_local(v) |
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v = v.reshape(B, self.num_heads, -1, self.N).permute(0, 1, 3, 2) |
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attn = (q @ k) * self.scale |
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attn = attn + self.get_attention_biases(x.device) |
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attn = attn.softmax(dim=-1) |
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x = (attn @ v).transpose(2, 3) |
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x = x.reshape(B, self.dh, self.resolution2[0], self.resolution2[1]) + v_local |
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x = self.act(x) |
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x = self.proj(x) |
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return x |
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class Downsample(nn.Module): |
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def __init__( |
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self, |
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in_chs, |
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out_chs, |
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kernel_size=3, |
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stride=2, |
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padding=1, |
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resolution=7, |
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use_attn=False, |
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act_layer=nn.GELU, |
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norm_layer=nn.BatchNorm2d, |
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): |
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super().__init__() |
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kernel_size = to_2tuple(kernel_size) |
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stride = to_2tuple(stride) |
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padding = to_2tuple(padding) |
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norm_layer = norm_layer or nn.Identity() |
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self.conv = ConvNorm( |
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in_chs, |
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out_chs, |
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kernel_size=kernel_size, |
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stride=stride, |
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padding=padding, |
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norm_layer=norm_layer, |
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) |
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if use_attn: |
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self.attn = Attention2dDownsample( |
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dim=in_chs, |
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out_dim=out_chs, |
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resolution=resolution, |
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act_layer=act_layer, |
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) |
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else: |
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self.attn = None |
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def forward(self, x): |
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out = self.conv(x) |
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if self.attn is not None: |
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return self.attn(x) + out |
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return out |
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class ConvMlpWithNorm(nn.Module): |
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""" |
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Implementation of MLP with 1*1 convolutions. |
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Input: tensor with shape [B, C, H, W] |
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""" |
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def __init__( |
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self, |
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in_features, |
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hidden_features=None, |
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out_features=None, |
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act_layer=nn.GELU, |
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norm_layer=nn.BatchNorm2d, |
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drop=0., |
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mid_conv=False, |
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): |
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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 = ConvNormAct( |
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in_features, hidden_features, 1, |
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bias=True, norm_layer=norm_layer, act_layer=act_layer) |
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if mid_conv: |
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self.mid = ConvNormAct( |
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hidden_features, hidden_features, 3, |
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groups=hidden_features, bias=True, norm_layer=norm_layer, act_layer=act_layer) |
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else: |
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self.mid = nn.Identity() |
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self.drop1 = nn.Dropout(drop) |
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self.fc2 = ConvNorm(hidden_features, out_features, 1, norm_layer=norm_layer) |
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self.drop2 = 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.mid(x) |
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x = self.drop1(x) |
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x = self.fc2(x) |
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x = self.drop2(x) |
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return x |
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class LayerScale2d(nn.Module): |
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def __init__(self, dim, init_values=1e-5, inplace=False): |
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super().__init__() |
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self.inplace = inplace |
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self.gamma = nn.Parameter(init_values * torch.ones(dim)) |
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def forward(self, x): |
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gamma = self.gamma.view(1, -1, 1, 1) |
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return x.mul_(gamma) if self.inplace else x * gamma |
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class EfficientFormerV2Block(nn.Module): |
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def __init__( |
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self, |
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dim, |
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mlp_ratio=4., |
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act_layer=nn.GELU, |
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norm_layer=nn.BatchNorm2d, |
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proj_drop=0., |
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drop_path=0., |
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layer_scale_init_value=1e-5, |
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resolution=7, |
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stride=None, |
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use_attn=True, |
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): |
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super().__init__() |
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if use_attn: |
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self.token_mixer = Attention2d( |
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dim, |
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resolution=resolution, |
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act_layer=act_layer, |
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stride=stride, |
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) |
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self.ls1 = LayerScale2d( |
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dim, layer_scale_init_value) if layer_scale_init_value is not None else nn.Identity() |
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self.drop_path1 = DropPath(drop_path) if drop_path > 0. else nn.Identity() |
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else: |
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self.token_mixer = None |
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self.ls1 = None |
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self.drop_path1 = None |
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self.mlp = ConvMlpWithNorm( |
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in_features=dim, |
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hidden_features=int(dim * mlp_ratio), |
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act_layer=act_layer, |
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norm_layer=norm_layer, |
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drop=proj_drop, |
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mid_conv=True, |
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) |
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self.ls2 = LayerScale2d( |
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dim, layer_scale_init_value) if layer_scale_init_value is not None else nn.Identity() |
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self.drop_path2 = DropPath(drop_path) if drop_path > 0. else nn.Identity() |
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def forward(self, x): |
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if self.token_mixer is not None: |
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x = x + self.drop_path1(self.ls1(self.token_mixer(x))) |
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x = x + self.drop_path2(self.ls2(self.mlp(x))) |
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return x |
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class Stem4(nn.Sequential): |
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def __init__(self, in_chs, out_chs, act_layer=nn.GELU, norm_layer=nn.BatchNorm2d): |
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super().__init__() |
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self.stride = 4 |
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self.conv1 = ConvNormAct( |
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in_chs, out_chs // 2, kernel_size=3, stride=2, padding=1, bias=True, |
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norm_layer=norm_layer, act_layer=act_layer |
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) |
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self.conv2 = ConvNormAct( |
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out_chs // 2, out_chs, kernel_size=3, stride=2, padding=1, bias=True, |
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norm_layer=norm_layer, act_layer=act_layer |
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) |
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class EfficientFormerV2Stage(nn.Module): |
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def __init__( |
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self, |
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dim, |
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dim_out, |
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depth, |
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resolution=7, |
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downsample=True, |
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block_stride=None, |
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downsample_use_attn=False, |
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block_use_attn=False, |
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num_vit=1, |
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mlp_ratio=4., |
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proj_drop=.0, |
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drop_path=0., |
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layer_scale_init_value=1e-5, |
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act_layer=nn.GELU, |
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norm_layer=nn.BatchNorm2d, |
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|
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): |
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super().__init__() |
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self.grad_checkpointing = False |
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mlp_ratio = to_ntuple(depth)(mlp_ratio) |
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resolution = to_2tuple(resolution) |
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|
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if downsample: |
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self.downsample = Downsample( |
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dim, |
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dim_out, |
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use_attn=downsample_use_attn, |
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resolution=resolution, |
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norm_layer=norm_layer, |
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act_layer=act_layer, |
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) |
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dim = dim_out |
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resolution = tuple([math.ceil(r / 2) for r in resolution]) |
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else: |
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assert dim == dim_out |
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self.downsample = nn.Identity() |
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blocks = [] |
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for block_idx in range(depth): |
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remain_idx = depth - num_vit - 1 |
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b = EfficientFormerV2Block( |
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dim, |
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resolution=resolution, |
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stride=block_stride, |
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mlp_ratio=mlp_ratio[block_idx], |
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use_attn=block_use_attn and block_idx > remain_idx, |
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proj_drop=proj_drop, |
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drop_path=drop_path[block_idx], |
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layer_scale_init_value=layer_scale_init_value, |
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act_layer=act_layer, |
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norm_layer=norm_layer, |
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) |
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blocks += [b] |
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self.blocks = nn.Sequential(*blocks) |
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|
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def forward(self, x): |
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x = self.downsample(x) |
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if self.grad_checkpointing and not torch.jit.is_scripting(): |
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x = checkpoint_seq(self.blocks, x) |
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else: |
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x = self.blocks(x) |
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return x |
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|
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class EfficientFormerV2(nn.Module): |
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def __init__( |
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self, |
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depths, |
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in_chans=3, |
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img_size=224, |
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global_pool='avg', |
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embed_dims=None, |
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downsamples=None, |
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mlp_ratios=4, |
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norm_layer='batchnorm2d', |
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norm_eps=1e-5, |
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act_layer='gelu', |
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num_classes=1000, |
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drop_rate=0., |
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proj_drop_rate=0., |
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drop_path_rate=0., |
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layer_scale_init_value=1e-5, |
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num_vit=0, |
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distillation=True, |
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): |
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super().__init__() |
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assert global_pool in ('avg', '') |
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self.num_classes = num_classes |
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self.global_pool = global_pool |
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self.feature_info = [] |
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img_size = to_2tuple(img_size) |
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norm_layer = partial(get_norm_layer(norm_layer), eps=norm_eps) |
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act_layer = get_act_layer(act_layer) |
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|
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self.stem = Stem4(in_chans, embed_dims[0], act_layer=act_layer, norm_layer=norm_layer) |
|
prev_dim = embed_dims[0] |
|
stride = 4 |
|
|
|
num_stages = len(depths) |
|
dpr = [x.tolist() for x in torch.linspace(0, drop_path_rate, sum(depths)).split(depths)] |
|
downsamples = downsamples or (False,) + (True,) * (len(depths) - 1) |
|
mlp_ratios = to_ntuple(num_stages)(mlp_ratios) |
|
stages = [] |
|
for i in range(num_stages): |
|
curr_resolution = tuple([math.ceil(s / stride) for s in img_size]) |
|
stage = EfficientFormerV2Stage( |
|
prev_dim, |
|
embed_dims[i], |
|
depth=depths[i], |
|
resolution=curr_resolution, |
|
downsample=downsamples[i], |
|
block_stride=2 if i == 2 else None, |
|
downsample_use_attn=i >= 3, |
|
block_use_attn=i >= 2, |
|
num_vit=num_vit, |
|
mlp_ratio=mlp_ratios[i], |
|
proj_drop=proj_drop_rate, |
|
drop_path=dpr[i], |
|
layer_scale_init_value=layer_scale_init_value, |
|
act_layer=act_layer, |
|
norm_layer=norm_layer, |
|
) |
|
if downsamples[i]: |
|
stride *= 2 |
|
prev_dim = embed_dims[i] |
|
self.feature_info += [dict(num_chs=prev_dim, reduction=stride, module=f'stages.{i}')] |
|
stages.append(stage) |
|
self.stages = nn.Sequential(*stages) |
|
|
|
|
|
self.num_features = embed_dims[-1] |
|
self.norm = norm_layer(embed_dims[-1]) |
|
self.head_drop = nn.Dropout(drop_rate) |
|
self.head = nn.Linear(embed_dims[-1], num_classes) if num_classes > 0 else nn.Identity() |
|
self.dist = distillation |
|
if self.dist: |
|
self.head_dist = nn.Linear(embed_dims[-1], num_classes) if num_classes > 0 else nn.Identity() |
|
else: |
|
self.head_dist = None |
|
|
|
self.apply(self.init_weights) |
|
self.distilled_training = False |
|
|
|
|
|
def init_weights(self, m): |
|
if isinstance(m, nn.Linear): |
|
trunc_normal_(m.weight, std=.02) |
|
if m.bias is not None: |
|
nn.init.constant_(m.bias, 0) |
|
|
|
@torch.jit.ignore |
|
def no_weight_decay(self): |
|
return {k for k, _ in self.named_parameters() if 'attention_biases' in k} |
|
|
|
@torch.jit.ignore |
|
def group_matcher(self, coarse=False): |
|
matcher = dict( |
|
stem=r'^stem', |
|
blocks=[(r'^stages\.(\d+)', None), (r'^norm', (99999,))] |
|
) |
|
return matcher |
|
|
|
@torch.jit.ignore |
|
def set_grad_checkpointing(self, enable=True): |
|
for s in self.stages: |
|
s.grad_checkpointing = enable |
|
|
|
@torch.jit.ignore |
|
def get_classifier(self): |
|
return self.head, self.head_dist |
|
|
|
def reset_classifier(self, num_classes, global_pool=None): |
|
self.num_classes = num_classes |
|
if global_pool is not None: |
|
self.global_pool = global_pool |
|
self.head = nn.Linear(self.num_features, num_classes) if num_classes > 0 else nn.Identity() |
|
self.head_dist = nn.Linear(self.num_features, num_classes) if num_classes > 0 else nn.Identity() |
|
|
|
@torch.jit.ignore |
|
def set_distilled_training(self, enable=True): |
|
self.distilled_training = enable |
|
|
|
def forward_features(self, x): |
|
x = self.stem(x) |
|
x = self.stages(x) |
|
x = self.norm(x) |
|
return x |
|
|
|
def forward_head(self, x, pre_logits: bool = False): |
|
if self.global_pool == 'avg': |
|
x = x.mean(dim=(2, 3)) |
|
x = self.head_drop(x) |
|
if pre_logits: |
|
return x |
|
x, x_dist = self.head(x), self.head_dist(x) |
|
if self.distilled_training and self.training and not torch.jit.is_scripting(): |
|
|
|
return x, x_dist |
|
else: |
|
|
|
return (x + x_dist) / 2 |
|
|
|
def forward(self, x): |
|
x = self.forward_features(x) |
|
x = self.forward_head(x) |
|
return x |
|
|
|
|
|
def _cfg(url='', **kwargs): |
|
return { |
|
'url': url, |
|
'num_classes': 1000, 'input_size': (3, 224, 224), 'pool_size': None, 'fixed_input_size': True, |
|
'crop_pct': .95, 'interpolation': 'bicubic', |
|
'mean': IMAGENET_DEFAULT_MEAN, 'std': IMAGENET_DEFAULT_STD, |
|
'classifier': ('head', 'head_dist'), 'first_conv': 'stem.conv1.conv', |
|
**kwargs |
|
} |
|
|
|
|
|
default_cfgs = generate_default_cfgs({ |
|
'efficientformerv2_s0.snap_dist_in1k': _cfg( |
|
hf_hub_id='timm/', |
|
), |
|
'efficientformerv2_s1.snap_dist_in1k': _cfg( |
|
hf_hub_id='timm/', |
|
), |
|
'efficientformerv2_s2.snap_dist_in1k': _cfg( |
|
hf_hub_id='timm/', |
|
), |
|
'efficientformerv2_l.snap_dist_in1k': _cfg( |
|
hf_hub_id='timm/', |
|
), |
|
}) |
|
|
|
|
|
def _create_efficientformerv2(variant, pretrained=False, **kwargs): |
|
out_indices = kwargs.pop('out_indices', (0, 1, 2, 3)) |
|
model = build_model_with_cfg( |
|
EfficientFormerV2, variant, pretrained, |
|
feature_cfg=dict(flatten_sequential=True, out_indices=out_indices), |
|
**kwargs) |
|
return model |
|
|
|
|
|
@register_model |
|
def efficientformerv2_s0(pretrained=False, **kwargs) -> EfficientFormerV2: |
|
model_args = dict( |
|
depths=EfficientFormer_depth['S0'], |
|
embed_dims=EfficientFormer_width['S0'], |
|
num_vit=2, |
|
drop_path_rate=0.0, |
|
mlp_ratios=EfficientFormer_expansion_ratios['S0'], |
|
) |
|
return _create_efficientformerv2('efficientformerv2_s0', pretrained=pretrained, **dict(model_args, **kwargs)) |
|
|
|
|
|
@register_model |
|
def efficientformerv2_s1(pretrained=False, **kwargs) -> EfficientFormerV2: |
|
model_args = dict( |
|
depths=EfficientFormer_depth['S1'], |
|
embed_dims=EfficientFormer_width['S1'], |
|
num_vit=2, |
|
drop_path_rate=0.0, |
|
mlp_ratios=EfficientFormer_expansion_ratios['S1'], |
|
) |
|
return _create_efficientformerv2('efficientformerv2_s1', pretrained=pretrained, **dict(model_args, **kwargs)) |
|
|
|
|
|
@register_model |
|
def efficientformerv2_s2(pretrained=False, **kwargs) -> EfficientFormerV2: |
|
model_args = dict( |
|
depths=EfficientFormer_depth['S2'], |
|
embed_dims=EfficientFormer_width['S2'], |
|
num_vit=4, |
|
drop_path_rate=0.02, |
|
mlp_ratios=EfficientFormer_expansion_ratios['S2'], |
|
) |
|
return _create_efficientformerv2('efficientformerv2_s2', pretrained=pretrained, **dict(model_args, **kwargs)) |
|
|
|
|
|
@register_model |
|
def efficientformerv2_l(pretrained=False, **kwargs) -> EfficientFormerV2: |
|
model_args = dict( |
|
depths=EfficientFormer_depth['L'], |
|
embed_dims=EfficientFormer_width['L'], |
|
num_vit=6, |
|
drop_path_rate=0.1, |
|
mlp_ratios=EfficientFormer_expansion_ratios['L'], |
|
) |
|
return _create_efficientformerv2('efficientformerv2_l', pretrained=pretrained, **dict(model_args, **kwargs)) |
|
|
|
|