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""" |
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Copyright (c) 2022, salesforce.com, inc. |
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All rights reserved. |
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SPDX-License-Identifier: BSD-3-Clause |
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For full license text, see the LICENSE file in the repo root or https://opensource.org/licenses/BSD-3-Clause |
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Based on timm code base |
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https://github.com/rwightman/pytorch-image-models/tree/master/timm |
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""" |
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""" |
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Copyright (c) 2023, salesforce.com, inc. |
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All rights reserved. |
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SPDX-License-Identifier: BSD-3-Clause |
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For full license text, see the LICENSE file in the repo root or https://opensource.org/licenses/BSD-3-Clause |
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""" |
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""" |
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Copyright (c) 2023, salesforce.com, inc. |
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All rights reserved. |
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SPDX-License-Identifier: BSD-3-Clause |
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For full license text, see the LICENSE file in the repo root or https://opensource.org/licenses/BSD-3-Clause |
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""" |
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""" |
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* Copyright (c) 2023, salesforce.com, inc. |
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* All rights reserved. |
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* SPDX-License-Identifier: BSD-3-Clause |
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* For full license text, see LICENSE.txt file in the repo root or https://opensource.org/licenses/BSD-3-Clause |
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* By Junnan Li |
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* Based on huggingface code base |
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* https://github.com/huggingface/transformers/blob/v4.15.0/src/transformers/models/bert |
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""" |
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|
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from dataclasses import dataclass |
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|
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import torch |
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from einops import rearrange |
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from torch import Tensor, nn |
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from safetensors.torch import load_file as load_sft |
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|
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import torch.nn as nn |
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import torch |
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|
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|
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import os |
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|
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from typing import Any, Dict, List, Optional, Union |
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from transformers import LlamaTokenizer |
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|
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from PIL import Image |
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from torchvision import transforms |
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|
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import torch.utils.checkpoint as checkpoint |
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|
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DIFFUSION_NAME = 'stabilityai/stable-diffusion-2-1-unclip' |
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|
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import logging |
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|
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import torch |
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import torch.distributed as dist |
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import torch.nn as nn |
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from torch.cuda.amp import autocast as autocast |
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from torch.nn import functional as F |
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import numpy as np |
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from functools import partial |
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from einops import rearrange |
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|
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import contextlib |
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import logging |
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import os |
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import time |
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import datetime |
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|
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import torch |
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import torch.nn as nn |
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import torch.distributed as dist |
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import torch.nn.functional as F |
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|
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from timm.models.layers import drop_path, to_2tuple, trunc_normal_ |
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|
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from transformers import BertTokenizer |
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|
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import math |
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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 functools import partial |
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|
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from timm.models.vision_transformer import _cfg, PatchEmbed |
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from timm.models.registry import register_model |
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from timm.models.layers import trunc_normal_, DropPath |
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from timm.models.helpers import named_apply, adapt_input_conv |
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|
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import math |
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import os |
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import warnings |
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from dataclasses import dataclass |
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from typing import Optional, Tuple, Dict, Any |
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|
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import torch |
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from torch import Tensor, device, dtype, nn |
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import torch.utils.checkpoint |
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from torch.nn import CrossEntropyLoss |
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import torch.nn.functional as F |
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import numpy as np |
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from transformers.activations import ACT2FN |
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from transformers.file_utils import ( |
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ModelOutput, ) |
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from transformers.modeling_outputs import ( |
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BaseModelOutputWithPastAndCrossAttentions, |
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BaseModelOutputWithPoolingAndCrossAttentions, |
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CausalLMOutputWithCrossAttentions, |
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MaskedLMOutput, |
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MultipleChoiceModelOutput, |
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NextSentencePredictorOutput, |
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QuestionAnsweringModelOutput, |
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SequenceClassifierOutput, |
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TokenClassifierOutput, |
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) |
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from transformers.modeling_utils import ( |
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PreTrainedModel, |
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apply_chunking_to_forward, |
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find_pruneable_heads_and_indices, |
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prune_linear_layer, |
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) |
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from transformers.models.bert.configuration_bert import BertConfig |
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@dataclass |
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class AutoEncoderParams: |
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resolution: int |
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in_channels: int |
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downsample: int |
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ch: int |
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out_ch: int |
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ch_mult: list[int] |
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num_res_blocks: int |
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z_channels: int |
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scale_factor: float |
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shift_factor: float |
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|
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def swish(x: Tensor) -> Tensor: |
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return x * torch.sigmoid(x) |
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|
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class AttnBlock(nn.Module): |
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def __init__(self, in_channels: int): |
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super().__init__() |
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self.in_channels = in_channels |
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|
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self.norm = nn.GroupNorm(num_groups=32, num_channels=in_channels, eps=1e-6, affine=True) |
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self.q = nn.Conv2d(in_channels, in_channels, kernel_size=1) |
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self.k = nn.Conv2d(in_channels, in_channels, kernel_size=1) |
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self.v = nn.Conv2d(in_channels, in_channels, kernel_size=1) |
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self.proj_out = nn.Conv2d(in_channels, in_channels, kernel_size=1) |
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|
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def attention(self, h_: Tensor) -> Tensor: |
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h_ = self.norm(h_) |
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q = self.q(h_) |
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k = self.k(h_) |
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v = self.v(h_) |
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|
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b, c, h, w = q.shape |
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q = rearrange(q, "b c h w -> b 1 (h w) c").contiguous() |
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k = rearrange(k, "b c h w -> b 1 (h w) c").contiguous() |
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v = rearrange(v, "b c h w -> b 1 (h w) c").contiguous() |
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h_ = nn.functional.scaled_dot_product_attention(q, k, v) |
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return rearrange(h_, "b 1 (h w) c -> b c h w", h=h, w=w, c=c, b=b) |
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|
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def forward(self, x: Tensor) -> Tensor: |
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return x + self.proj_out(self.attention(x)) |
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|
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class ResnetBlock(nn.Module): |
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def __init__(self, in_channels: int, out_channels: int): |
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super().__init__() |
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self.in_channels = in_channels |
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out_channels = in_channels if out_channels is None else out_channels |
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self.out_channels = out_channels |
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|
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self.norm1 = nn.GroupNorm(num_groups=32, num_channels=in_channels, eps=1e-6, affine=True) |
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self.conv1 = nn.Conv2d(in_channels, out_channels, kernel_size=3, stride=1, padding=1) |
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self.norm2 = nn.GroupNorm(num_groups=32, num_channels=out_channels, eps=1e-6, affine=True) |
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self.conv2 = nn.Conv2d(out_channels, out_channels, kernel_size=3, stride=1, padding=1) |
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if self.in_channels != self.out_channels: |
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self.nin_shortcut = nn.Conv2d(in_channels, out_channels, kernel_size=1, stride=1, padding=0) |
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|
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def forward(self, x): |
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h = x |
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h = self.norm1(h) |
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h = swish(h) |
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h = self.conv1(h) |
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h = self.norm2(h) |
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h = swish(h) |
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h = self.conv2(h) |
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if self.in_channels != self.out_channels: |
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x = self.nin_shortcut(x) |
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return x + h |
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class Downsample(nn.Module): |
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def __init__(self, in_channels: int): |
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super().__init__() |
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self.conv = nn.Conv2d(in_channels, in_channels, kernel_size=3, stride=2, padding=0) |
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|
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def forward(self, x: Tensor): |
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pad = (0, 1, 0, 1) |
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x = nn.functional.pad(x, pad, mode="constant", value=0) |
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x = self.conv(x) |
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return x |
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class Upsample(nn.Module): |
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def __init__(self, in_channels: int): |
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super().__init__() |
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self.conv = nn.Conv2d(in_channels, in_channels, kernel_size=3, stride=1, padding=1) |
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|
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def forward(self, x: Tensor): |
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x = nn.functional.interpolate(x, scale_factor=2.0, mode="nearest") |
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x = self.conv(x) |
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return x |
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class Encoder(nn.Module): |
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def __init__( |
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self, |
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resolution: int, |
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in_channels: int, |
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ch: int, |
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ch_mult: list[int], |
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num_res_blocks: int, |
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z_channels: int, |
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): |
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super().__init__() |
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self.ch = ch |
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self.num_resolutions = len(ch_mult) |
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self.num_res_blocks = num_res_blocks |
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self.resolution = resolution |
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self.in_channels = in_channels |
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self.conv_in = nn.Conv2d(in_channels, self.ch, kernel_size=3, stride=1, padding=1) |
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curr_res = resolution |
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in_ch_mult = (1,) + tuple(ch_mult) |
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self.in_ch_mult = in_ch_mult |
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self.down = nn.ModuleList() |
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block_in = self.ch |
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for i_level in range(self.num_resolutions): |
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block = nn.ModuleList() |
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attn = nn.ModuleList() |
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block_in = ch * in_ch_mult[i_level] |
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block_out = ch * ch_mult[i_level] |
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for _ in range(self.num_res_blocks): |
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block.append(ResnetBlock(in_channels=block_in, out_channels=block_out)) |
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block_in = block_out |
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down = nn.Module() |
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down.block = block |
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down.attn = attn |
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if i_level != self.num_resolutions - 1: |
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down.downsample = Downsample(block_in) |
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curr_res = curr_res // 2 |
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self.down.append(down) |
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self.mid = nn.Module() |
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self.mid.block_1 = ResnetBlock(in_channels=block_in, out_channels=block_in) |
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self.mid.attn_1 = AttnBlock(block_in) |
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self.mid.block_2 = ResnetBlock(in_channels=block_in, out_channels=block_in) |
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self.norm_out = nn.GroupNorm(num_groups=32, num_channels=block_in, eps=1e-6, affine=True) |
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self.conv_out = nn.Conv2d(block_in, 2 * z_channels, kernel_size=3, stride=1, padding=1) |
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|
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def forward(self, x: Tensor) -> Tensor: |
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|
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hs = [self.conv_in(x)] |
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for i_level in range(self.num_resolutions): |
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for i_block in range(self.num_res_blocks): |
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h = self.down[i_level].block[i_block](hs[-1]) |
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if len(self.down[i_level].attn) > 0: |
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h = self.down[i_level].attn[i_block](h) |
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hs.append(h) |
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if i_level != self.num_resolutions - 1: |
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hs.append(self.down[i_level].downsample(hs[-1])) |
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|
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h = hs[-1] |
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h = self.mid.block_1(h) |
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h = self.mid.attn_1(h) |
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h = self.mid.block_2(h) |
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|
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h = self.norm_out(h) |
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h = swish(h) |
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h = self.conv_out(h) |
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return h |
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|
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class Decoder(nn.Module): |
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def __init__( |
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self, |
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ch: int, |
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out_ch: int, |
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ch_mult: list[int], |
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num_res_blocks: int, |
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in_channels: int, |
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resolution: int, |
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z_channels: int, |
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): |
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super().__init__() |
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self.ch = ch |
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self.num_resolutions = len(ch_mult) |
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self.num_res_blocks = num_res_blocks |
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self.resolution = resolution |
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self.in_channels = in_channels |
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self.ffactor = 2 ** (self.num_resolutions - 1) |
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block_in = ch * ch_mult[self.num_resolutions - 1] |
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curr_res = resolution // 2 ** (self.num_resolutions - 1) |
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self.z_shape = (1, z_channels, curr_res, curr_res) |
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self.conv_in = nn.Conv2d(z_channels, block_in, kernel_size=3, stride=1, padding=1) |
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|
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self.mid = nn.Module() |
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self.mid.block_1 = ResnetBlock(in_channels=block_in, out_channels=block_in) |
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self.mid.attn_1 = AttnBlock(block_in) |
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self.mid.block_2 = ResnetBlock(in_channels=block_in, out_channels=block_in) |
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|
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self.up = nn.ModuleList() |
|
for i_level in reversed(range(self.num_resolutions)): |
|
block = nn.ModuleList() |
|
attn = nn.ModuleList() |
|
block_out = ch * ch_mult[i_level] |
|
for _ in range(self.num_res_blocks + 1): |
|
block.append(ResnetBlock(in_channels=block_in, out_channels=block_out)) |
|
block_in = block_out |
|
up = nn.Module() |
|
up.block = block |
|
up.attn = attn |
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if i_level != 0: |
|
up.upsample = Upsample(block_in) |
|
curr_res = curr_res * 2 |
|
self.up.insert(0, up) |
|
|
|
|
|
self.norm_out = nn.GroupNorm(num_groups=32, num_channels=block_in, eps=1e-6, affine=True) |
|
self.conv_out = nn.Conv2d(block_in, out_ch, kernel_size=3, stride=1, padding=1) |
|
|
|
def forward(self, z: Tensor) -> Tensor: |
|
|
|
h = self.conv_in(z) |
|
|
|
|
|
h = self.mid.block_1(h) |
|
h = self.mid.attn_1(h) |
|
h = self.mid.block_2(h) |
|
|
|
|
|
for i_level in reversed(range(self.num_resolutions)): |
|
for i_block in range(self.num_res_blocks + 1): |
|
h = self.up[i_level].block[i_block](h) |
|
if len(self.up[i_level].attn) > 0: |
|
h = self.up[i_level].attn[i_block](h) |
|
if i_level != 0: |
|
h = self.up[i_level].upsample(h) |
|
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|
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h = self.norm_out(h) |
|
h = swish(h) |
|
h = self.conv_out(h) |
|
return h |
|
|
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|
|
class DiagonalGaussian(nn.Module): |
|
def __init__(self, sample: bool = True, chunk_dim: int = 1): |
|
super().__init__() |
|
self.sample = sample |
|
self.chunk_dim = chunk_dim |
|
|
|
def forward(self, z: Tensor) -> Tensor: |
|
mean, logvar = torch.chunk(z, 2, dim=self.chunk_dim) |
|
if self.sample: |
|
std = torch.exp(0.5 * logvar) |
|
return mean + std * torch.randn_like(mean) |
|
else: |
|
return mean |
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|
|
|
|
class AutoEncoder(nn.Module): |
|
def __init__(self, params: AutoEncoderParams): |
|
super().__init__() |
|
self.encoder = Encoder( |
|
resolution=params.resolution, |
|
in_channels=params.in_channels, |
|
ch=params.ch, |
|
ch_mult=params.ch_mult, |
|
num_res_blocks=params.num_res_blocks, |
|
z_channels=params.z_channels, |
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) |
|
self.decoder = Decoder( |
|
resolution=params.resolution, |
|
in_channels=params.in_channels, |
|
ch=params.ch, |
|
out_ch=params.out_ch, |
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ch_mult=params.ch_mult, |
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num_res_blocks=params.num_res_blocks, |
|
z_channels=params.z_channels, |
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) |
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self.reg = DiagonalGaussian() |
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|
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self.scale_factor = params.scale_factor |
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self.shift_factor = params.shift_factor |
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|
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def encode(self, x: Tensor) -> Tensor: |
|
z = self.reg(self.encoder(x)) |
|
z = self.scale_factor * (z - self.shift_factor) |
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return z |
|
|
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def decode(self, z: Tensor) -> Tensor: |
|
z = z / self.scale_factor + self.shift_factor |
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return self.decoder(z) |
|
|
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def forward(self, x: Tensor) -> Tensor: |
|
return self.decode(self.encode(x)) |
|
|
|
|
|
def print_load_warning(missing: list[str], unexpected: list[str]) -> None: |
|
if len(missing) > 0 and len(unexpected) > 0: |
|
print(f"Got {len(missing)} missing keys:\n\t" + "\n\t".join(missing)) |
|
print("\n" + "-" * 79 + "\n") |
|
print(f"Got {len(unexpected)} unexpected keys:\n\t" + "\n\t".join(unexpected)) |
|
elif len(missing) > 0: |
|
print(f"Got {len(missing)} missing keys:\n\t" + "\n\t".join(missing)) |
|
elif len(unexpected) > 0: |
|
print(f"Got {len(unexpected)} unexpected keys:\n\t" + "\n\t".join(unexpected)) |
|
|
|
|
|
def load_ae(local_path: str) -> AutoEncoder: |
|
ae_params = AutoEncoderParams( |
|
resolution=256, |
|
in_channels=3, |
|
downsample=8, |
|
ch=128, |
|
out_ch=3, |
|
ch_mult=[1, 2, 4, 4], |
|
num_res_blocks=2, |
|
z_channels=16, |
|
scale_factor=0.3611, |
|
shift_factor=0.1159, |
|
) |
|
|
|
|
|
ae = AutoEncoder(ae_params) |
|
|
|
if local_path is not None: |
|
sd = load_sft(local_path) |
|
missing, unexpected = ae.load_state_dict(sd, strict=False, assign=True) |
|
print_load_warning(missing, unexpected) |
|
return ae, ae_params |
|
|
|
|
|
|
|
class DropPathEvaVit(nn.Module): |
|
"""Drop paths (Stochastic Depth) per sample (when applied in main path of residual blocks). |
|
""" |
|
def __init__(self, drop_prob=None): |
|
super(DropPathEvaVit, self).__init__() |
|
self.drop_prob = drop_prob |
|
|
|
def forward(self, x): |
|
return drop_path(x, self.drop_prob, self.training) |
|
|
|
def extra_repr(self) -> str: |
|
return 'p={}'.format(self.drop_prob) |
|
|
|
|
|
class MlpEvaVit(nn.Module): |
|
def __init__(self, in_features, hidden_features=None, out_features=None, act_layer=nn.GELU, drop=0.): |
|
super().__init__() |
|
out_features = out_features or in_features |
|
hidden_features = hidden_features or in_features |
|
self.fc1 = nn.Linear(in_features, hidden_features) |
|
self.act = act_layer() |
|
self.fc2 = nn.Linear(hidden_features, out_features) |
|
self.drop = nn.Dropout(drop) |
|
|
|
def forward(self, x): |
|
x = self.fc1(x) |
|
x = self.act(x) |
|
|
|
|
|
x = self.fc2(x) |
|
x = self.drop(x) |
|
return x |
|
|
|
|
|
class AttentionEvaVit(nn.Module): |
|
def __init__(self, |
|
dim, |
|
num_heads=8, |
|
qkv_bias=False, |
|
qk_scale=None, |
|
attn_drop=0., |
|
proj_drop=0., |
|
window_size=None, |
|
attn_head_dim=None): |
|
super().__init__() |
|
self.num_heads = num_heads |
|
head_dim = dim // num_heads |
|
if attn_head_dim is not None: |
|
head_dim = attn_head_dim |
|
all_head_dim = head_dim * self.num_heads |
|
self.scale = qk_scale or head_dim**-0.5 |
|
|
|
self.qkv = nn.Linear(dim, all_head_dim * 3, bias=False) |
|
if qkv_bias: |
|
self.q_bias = nn.Parameter(torch.zeros(all_head_dim)) |
|
self.v_bias = nn.Parameter(torch.zeros(all_head_dim)) |
|
else: |
|
self.q_bias = None |
|
self.v_bias = None |
|
|
|
if window_size: |
|
self.window_size = window_size |
|
self.num_relative_distance = (2 * window_size[0] - 1) * (2 * window_size[1] - 1) + 3 |
|
self.relative_position_bias_table = nn.Parameter(torch.zeros(self.num_relative_distance, |
|
num_heads)) |
|
|
|
|
|
|
|
coords_h = torch.arange(window_size[0]) |
|
coords_w = torch.arange(window_size[1]) |
|
coords = torch.stack(torch.meshgrid([coords_h, coords_w])) |
|
coords_flatten = torch.flatten(coords, 1) |
|
relative_coords = coords_flatten[:, :, None] - coords_flatten[:, None, :] |
|
relative_coords = relative_coords.permute(1, 2, 0).contiguous() |
|
relative_coords[:, :, 0] += window_size[0] - 1 |
|
relative_coords[:, :, 1] += window_size[1] - 1 |
|
relative_coords[:, :, 0] *= 2 * window_size[1] - 1 |
|
relative_position_index = \ |
|
torch.zeros(size=(window_size[0] * window_size[1] + 1, ) * 2, dtype=relative_coords.dtype) |
|
relative_position_index[1:, 1:] = relative_coords.sum(-1) |
|
relative_position_index[0, 0:] = self.num_relative_distance - 3 |
|
relative_position_index[0:, 0] = self.num_relative_distance - 2 |
|
relative_position_index[0, 0] = self.num_relative_distance - 1 |
|
|
|
self.register_buffer("relative_position_index", relative_position_index) |
|
else: |
|
self.window_size = None |
|
self.relative_position_bias_table = None |
|
self.relative_position_index = None |
|
|
|
self.attn_drop = nn.Dropout(attn_drop) |
|
self.proj = nn.Linear(all_head_dim, dim) |
|
self.proj_drop = nn.Dropout(proj_drop) |
|
|
|
def forward(self, x, rel_pos_bias=None): |
|
B, N, C = x.shape |
|
qkv_bias = None |
|
if self.q_bias is not None: |
|
qkv_bias = torch.cat((self.q_bias, torch.zeros_like(self.v_bias, requires_grad=False), self.v_bias)) |
|
|
|
qkv = F.linear(input=x, weight=self.qkv.weight, bias=qkv_bias) |
|
qkv = qkv.reshape(B, N, 3, self.num_heads, -1).permute(2, 0, 3, 1, 4) |
|
q, k, v = qkv[0], qkv[1], qkv[2] |
|
|
|
q = q * self.scale |
|
attn = (q @ k.transpose(-2, -1)) |
|
|
|
if self.relative_position_bias_table is not None: |
|
relative_position_bias = \ |
|
self.relative_position_bias_table[self.relative_position_index.view(-1)].view( |
|
self.window_size[0] * self.window_size[1] + 1, |
|
self.window_size[0] * self.window_size[1] + 1, -1) |
|
relative_position_bias = relative_position_bias.permute(2, 0, 1).contiguous() |
|
attn = attn + relative_position_bias.unsqueeze(0) |
|
|
|
if rel_pos_bias is not None: |
|
attn = attn + rel_pos_bias |
|
|
|
attn = attn.softmax(dim=-1) |
|
attn = self.attn_drop(attn) |
|
|
|
x = (attn @ v).transpose(1, 2).reshape(B, N, -1) |
|
x = self.proj(x) |
|
x = self.proj_drop(x) |
|
return x |
|
|
|
|
|
class BlockEvaVit(nn.Module): |
|
def __init__(self, |
|
dim, |
|
num_heads, |
|
mlp_ratio=4., |
|
qkv_bias=False, |
|
qk_scale=None, |
|
drop=0., |
|
attn_drop=0., |
|
drop_path=0., |
|
init_values=None, |
|
act_layer=nn.GELU, |
|
norm_layer=nn.LayerNorm, |
|
window_size=None, |
|
attn_head_dim=None): |
|
super().__init__() |
|
self.norm1 = norm_layer(dim) |
|
self.attn = AttentionEvaVit(dim, |
|
num_heads=num_heads, |
|
qkv_bias=qkv_bias, |
|
qk_scale=qk_scale, |
|
attn_drop=attn_drop, |
|
proj_drop=drop, |
|
window_size=window_size, |
|
attn_head_dim=attn_head_dim) |
|
|
|
self.drop_path = DropPathEvaVit(drop_path) if drop_path > 0. else nn.Identity() |
|
self.norm2 = norm_layer(dim) |
|
mlp_hidden_dim = int(dim * mlp_ratio) |
|
self.mlp = MlpEvaVit(in_features=dim, hidden_features=mlp_hidden_dim, act_layer=act_layer, drop=drop) |
|
|
|
if init_values is not None and init_values > 0: |
|
self.gamma_1 = nn.Parameter(init_values * torch.ones((dim)), requires_grad=True) |
|
self.gamma_2 = nn.Parameter(init_values * torch.ones((dim)), requires_grad=True) |
|
else: |
|
self.gamma_1, self.gamma_2 = None, None |
|
|
|
def forward(self, x, rel_pos_bias=None): |
|
if self.gamma_1 is None: |
|
x = x + self.drop_path(self.attn(self.norm1(x), rel_pos_bias=rel_pos_bias)) |
|
x = x + self.drop_path(self.mlp(self.norm2(x))) |
|
else: |
|
x = x + self.drop_path(self.gamma_1 * self.attn(self.norm1(x), rel_pos_bias=rel_pos_bias)) |
|
x = x + self.drop_path(self.gamma_2 * self.mlp(self.norm2(x))) |
|
return x |
|
|
|
|
|
class PatchEmbedEvaVit(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) |
|
num_patches = (img_size[1] // patch_size[1]) * (img_size[0] // patch_size[0]) |
|
self.patch_shape = (img_size[0] // patch_size[0], img_size[1] // patch_size[1]) |
|
self.img_size = img_size |
|
self.patch_size = patch_size |
|
self.num_patches = num_patches |
|
|
|
self.proj = nn.Conv2d(in_chans, embed_dim, kernel_size=patch_size, stride=patch_size) |
|
|
|
def forward(self, x, **kwargs): |
|
B, C, H, W = x.shape |
|
|
|
assert H == self.img_size[0] and W == self.img_size[1], \ |
|
f"Input image size ({H}*{W}) doesn't match model ({self.img_size[0]}*{self.img_size[1]})." |
|
x = self.proj(x).flatten(2).transpose(1, 2) |
|
return x |
|
|
|
|
|
class RelativePositionBiasEvaVit(nn.Module): |
|
def __init__(self, window_size, num_heads): |
|
super().__init__() |
|
self.window_size = window_size |
|
self.num_relative_distance = (2 * window_size[0] - 1) * (2 * window_size[1] - 1) + 3 |
|
self.relative_position_bias_table = nn.Parameter(torch.zeros(self.num_relative_distance, |
|
num_heads)) |
|
|
|
|
|
|
|
coords_h = torch.arange(window_size[0]) |
|
coords_w = torch.arange(window_size[1]) |
|
coords = torch.stack(torch.meshgrid([coords_h, coords_w])) |
|
coords_flatten = torch.flatten(coords, 1) |
|
relative_coords = coords_flatten[:, :, None] - coords_flatten[:, None, :] |
|
relative_coords = relative_coords.permute(1, 2, 0).contiguous() |
|
relative_coords[:, :, 0] += window_size[0] - 1 |
|
relative_coords[:, :, 1] += window_size[1] - 1 |
|
relative_coords[:, :, 0] *= 2 * window_size[1] - 1 |
|
relative_position_index = \ |
|
torch.zeros(size=(window_size[0] * window_size[1] + 1,) * 2, dtype=relative_coords.dtype) |
|
relative_position_index[1:, 1:] = relative_coords.sum(-1) |
|
relative_position_index[0, 0:] = self.num_relative_distance - 3 |
|
relative_position_index[0:, 0] = self.num_relative_distance - 2 |
|
relative_position_index[0, 0] = self.num_relative_distance - 1 |
|
|
|
self.register_buffer("relative_position_index", relative_position_index) |
|
|
|
|
|
|
|
def forward(self): |
|
relative_position_bias = \ |
|
self.relative_position_bias_table[self.relative_position_index.view(-1)].view( |
|
self.window_size[0] * self.window_size[1] + 1, |
|
self.window_size[0] * self.window_size[1] + 1, -1) |
|
return relative_position_bias.permute(2, 0, 1).contiguous() |
|
|
|
|
|
class VisionTransformerEvaVit(nn.Module): |
|
""" Vision Transformer with support for patch or hybrid CNN input stage |
|
""" |
|
def __init__(self, |
|
img_size=224, |
|
patch_size=16, |
|
in_chans=3, |
|
num_classes=1000, |
|
embed_dim=768, |
|
depth=12, |
|
num_heads=12, |
|
mlp_ratio=4., |
|
qkv_bias=False, |
|
qk_scale=None, |
|
drop_rate=0., |
|
attn_drop_rate=0., |
|
drop_path_rate=0., |
|
norm_layer=nn.LayerNorm, |
|
init_values=None, |
|
use_abs_pos_emb=True, |
|
use_rel_pos_bias=False, |
|
use_shared_rel_pos_bias=False, |
|
use_mean_pooling=True, |
|
init_scale=0.001, |
|
use_checkpoint=False): |
|
super().__init__() |
|
self.image_size = img_size |
|
self.num_classes = num_classes |
|
self.num_features = self.embed_dim = embed_dim |
|
|
|
self.patch_embed = PatchEmbedEvaVit(img_size=img_size, patch_size=patch_size, in_chans=in_chans, embed_dim=embed_dim) |
|
num_patches = self.patch_embed.num_patches |
|
|
|
self.cls_token = nn.Parameter(torch.zeros(1, 1, embed_dim)) |
|
if use_abs_pos_emb: |
|
self.pos_embed = nn.Parameter(torch.zeros(1, num_patches + 1, embed_dim)) |
|
else: |
|
self.pos_embed = None |
|
self.pos_drop = nn.Dropout(p=drop_rate) |
|
|
|
if use_shared_rel_pos_bias: |
|
self.rel_pos_bias = RelativePositionBiasEvaVit(window_size=self.patch_embed.patch_shape, num_heads=num_heads) |
|
else: |
|
self.rel_pos_bias = None |
|
self.use_checkpoint = use_checkpoint |
|
|
|
dpr = [x.item() for x in torch.linspace(0, drop_path_rate, depth)] |
|
self.use_rel_pos_bias = use_rel_pos_bias |
|
self.blocks = nn.ModuleList([ |
|
BlockEvaVit(dim=embed_dim, |
|
num_heads=num_heads, |
|
mlp_ratio=mlp_ratio, |
|
qkv_bias=qkv_bias, |
|
qk_scale=qk_scale, |
|
drop=drop_rate, |
|
attn_drop=attn_drop_rate, |
|
drop_path=dpr[i], |
|
norm_layer=norm_layer, |
|
init_values=init_values, |
|
window_size=self.patch_embed.patch_shape if use_rel_pos_bias else None) for i in range(depth) |
|
]) |
|
|
|
|
|
|
|
|
|
if self.pos_embed is not None: |
|
trunc_normal_(self.pos_embed, std=.02) |
|
trunc_normal_(self.cls_token, std=.02) |
|
|
|
|
|
|
|
self.apply(self._init_weights) |
|
self.fix_init_weight() |
|
self.ln_vision = nn.LayerNorm(self.num_features) |
|
|
|
def fix_init_weight(self): |
|
def rescale(param, layer_id): |
|
param.div_(math.sqrt(2.0 * layer_id)) |
|
|
|
for layer_id, layer in enumerate(self.blocks): |
|
rescale(layer.attn.proj.weight.data, layer_id + 1) |
|
rescale(layer.mlp.fc2.weight.data, layer_id + 1) |
|
|
|
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) |
|
|
|
_initialize_weights = _init_weights |
|
|
|
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 forward_features(self, x): |
|
x = self.patch_embed(x) |
|
batch_size, seq_len, _ = x.size() |
|
|
|
cls_tokens = self.cls_token.expand(batch_size, -1, -1) |
|
x = torch.cat((cls_tokens, x), dim=1) |
|
if self.pos_embed is not None: |
|
x = x + self.pos_embed |
|
x = self.pos_drop(x) |
|
|
|
rel_pos_bias = self.rel_pos_bias() if self.rel_pos_bias is not None else None |
|
for blk in self.blocks: |
|
if self.use_checkpoint: |
|
x = checkpoint.checkpoint(blk, x, rel_pos_bias) |
|
else: |
|
x = blk(x, rel_pos_bias) |
|
return x |
|
|
|
def forward(self, x): |
|
x = self.forward_features(x) |
|
|
|
return x |
|
|
|
def get_intermediate_layers(self, x): |
|
x = self.patch_embed(x) |
|
batch_size, seq_len, _ = x.size() |
|
|
|
cls_tokens = self.cls_token.expand(batch_size, -1, -1) |
|
x = torch.cat((cls_tokens, x), dim=1) |
|
if self.pos_embed is not None: |
|
x = x + self.pos_embed |
|
x = self.pos_drop(x) |
|
|
|
features = [] |
|
rel_pos_bias = self.rel_pos_bias() if self.rel_pos_bias is not None else None |
|
for blk in self.blocks: |
|
x = blk(x, rel_pos_bias) |
|
features.append(x) |
|
|
|
return features |
|
|
|
def get_num_layer(self, var_name=""): |
|
if var_name in ("cls_token", "mask_token", "pos_embed"): |
|
return 0 |
|
elif var_name.startswith("patch_embed"): |
|
return 0 |
|
elif var_name.startswith("rel_pos_bias"): |
|
return len(self.blocks) - 1 |
|
elif var_name.startswith("blocks"): |
|
layer_id = int(var_name.split('.')[1]) |
|
return layer_id + 1 |
|
else: |
|
return len(self.blocks) |
|
|
|
|
|
def create_eva_vit_g(img_size=224, drop_path_rate=0.4, use_checkpoint=False, precision="fp16", cache_dir="./",): |
|
model = VisionTransformerEvaVit( |
|
img_size=img_size, |
|
patch_size=14, |
|
use_mean_pooling=False, |
|
embed_dim=1408, |
|
depth=39, |
|
num_heads=1408 // 88, |
|
mlp_ratio=4.3637, |
|
qkv_bias=True, |
|
drop_path_rate=drop_path_rate, |
|
norm_layer=partial(nn.LayerNorm, eps=1e-6), |
|
use_checkpoint=use_checkpoint, |
|
) |
|
cache_path = cache_dir |
|
state_dict = torch.load(cache_path+"/eva_vit_g.pth", map_location="cpu") |
|
interpolate_pos_embed(model, state_dict) |
|
|
|
incompatible_keys = model.load_state_dict(state_dict, strict=False) |
|
|
|
|
|
return model |
|
|
|
class BertEmbeddings(nn.Module): |
|
"""Construct the embeddings from word and position embeddings.""" |
|
def __init__(self, config): |
|
super().__init__() |
|
self.word_embeddings = nn.Embedding(config.vocab_size, config.hidden_size, padding_idx=config.pad_token_id) |
|
self.position_embeddings = nn.Embedding(config.max_position_embeddings, config.hidden_size) |
|
|
|
|
|
|
|
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps) |
|
self.dropout = nn.Dropout(config.hidden_dropout_prob) |
|
|
|
|
|
self.register_buffer("position_ids", torch.arange(config.max_position_embeddings).expand((1, -1))) |
|
self.position_embedding_type = getattr(config, "position_embedding_type", "absolute") |
|
|
|
self.config = config |
|
|
|
def forward( |
|
self, |
|
input_ids=None, |
|
position_ids=None, |
|
query_embeds=None, |
|
past_key_values_length=0, |
|
): |
|
if input_ids is not None: |
|
seq_length = input_ids.size()[1] |
|
else: |
|
seq_length = 0 |
|
|
|
if position_ids is None: |
|
position_ids = self.position_ids[:, past_key_values_length:seq_length + past_key_values_length].clone() |
|
|
|
if input_ids is not None: |
|
embeddings = self.word_embeddings(input_ids) |
|
if self.position_embedding_type == "absolute": |
|
position_embeddings = self.position_embeddings(position_ids) |
|
embeddings = embeddings + position_embeddings |
|
|
|
if query_embeds is not None: |
|
embeddings = torch.cat((query_embeds, embeddings), dim=1) |
|
|
|
else: |
|
embeddings = query_embeds |
|
|
|
embeddings = self.LayerNorm(embeddings) |
|
embeddings = self.dropout(embeddings) |
|
return embeddings |
|
|
|
|
|
class BertSelfAttention(nn.Module): |
|
def __init__(self, config, is_cross_attention): |
|
super().__init__() |
|
self.config = config |
|
if config.hidden_size % config.num_attention_heads != 0 and not hasattr(config, "embedding_size"): |
|
raise ValueError("The hidden size (%d) is not a multiple of the number of attention " |
|
"heads (%d)" % (config.hidden_size, config.num_attention_heads)) |
|
|
|
self.num_attention_heads = config.num_attention_heads |
|
self.attention_head_size = int(config.hidden_size / config.num_attention_heads) |
|
self.all_head_size = self.num_attention_heads * self.attention_head_size |
|
|
|
self.query = nn.Linear(config.hidden_size, self.all_head_size) |
|
if is_cross_attention: |
|
self.key = nn.Linear(config.encoder_width, self.all_head_size) |
|
self.value = nn.Linear(config.encoder_width, self.all_head_size) |
|
else: |
|
self.key = nn.Linear(config.hidden_size, self.all_head_size) |
|
self.value = nn.Linear(config.hidden_size, self.all_head_size) |
|
|
|
self.dropout = nn.Dropout(config.attention_probs_dropout_prob) |
|
self.position_embedding_type = getattr(config, "position_embedding_type", "absolute") |
|
if (self.position_embedding_type == "relative_key" or self.position_embedding_type == "relative_key_query"): |
|
self.max_position_embeddings = config.max_position_embeddings |
|
self.distance_embedding = nn.Embedding(2 * config.max_position_embeddings - 1, self.attention_head_size) |
|
self.save_attention = False |
|
|
|
def save_attn_gradients(self, attn_gradients): |
|
self.attn_gradients = attn_gradients |
|
|
|
def get_attn_gradients(self): |
|
return self.attn_gradients |
|
|
|
def save_attention_map(self, attention_map): |
|
self.attention_map = attention_map |
|
|
|
def get_attention_map(self): |
|
return self.attention_map |
|
|
|
def transpose_for_scores(self, x): |
|
new_x_shape = x.size()[:-1] + ( |
|
self.num_attention_heads, |
|
self.attention_head_size, |
|
) |
|
x = x.view(*new_x_shape) |
|
return x.permute(0, 2, 1, 3) |
|
|
|
def forward( |
|
self, |
|
hidden_states, |
|
attention_mask=None, |
|
head_mask=None, |
|
encoder_hidden_states=None, |
|
encoder_attention_mask=None, |
|
past_key_value=None, |
|
output_attentions=False, |
|
): |
|
|
|
|
|
|
|
|
|
is_cross_attention = encoder_hidden_states is not None |
|
|
|
if is_cross_attention: |
|
key_layer = self.transpose_for_scores(self.key(encoder_hidden_states)) |
|
value_layer = self.transpose_for_scores(self.value(encoder_hidden_states)) |
|
|
|
attention_mask = encoder_attention_mask |
|
elif past_key_value is not None: |
|
key_layer = self.transpose_for_scores(self.key(hidden_states)) |
|
value_layer = self.transpose_for_scores(self.value(hidden_states)) |
|
key_layer = torch.cat([past_key_value[0], key_layer], dim=2) |
|
value_layer = torch.cat([past_key_value[1], value_layer], dim=2) |
|
|
|
else: |
|
key_layer = self.transpose_for_scores(self.key(hidden_states)) |
|
value_layer = self.transpose_for_scores(self.value(hidden_states)) |
|
|
|
mixed_query_layer = self.query(hidden_states) |
|
|
|
query_layer = self.transpose_for_scores(mixed_query_layer) |
|
|
|
|
|
|
|
past_key_value = (key_layer, value_layer) |
|
|
|
|
|
|
|
attention_scores = torch.matmul(query_layer, key_layer.transpose(-1, -2)) |
|
|
|
|
|
|
|
|
|
|
|
|
|
if (self.position_embedding_type == "relative_key" or self.position_embedding_type == "relative_key_query"): |
|
seq_length = hidden_states.size()[1] |
|
position_ids_l = torch.arange(seq_length, dtype=torch.long, device=hidden_states.device).view(-1, 1) |
|
position_ids_r = torch.arange(seq_length, dtype=torch.long, device=hidden_states.device).view(1, -1) |
|
distance = position_ids_l - position_ids_r |
|
positional_embedding = self.distance_embedding(distance + self.max_position_embeddings - 1) |
|
positional_embedding = positional_embedding.to(dtype=query_layer.dtype) |
|
|
|
if self.position_embedding_type == "relative_key": |
|
relative_position_scores = torch.einsum("bhld,lrd->bhlr", query_layer, positional_embedding) |
|
attention_scores = attention_scores + relative_position_scores |
|
elif self.position_embedding_type == "relative_key_query": |
|
relative_position_scores_query = torch.einsum("bhld,lrd->bhlr", query_layer, positional_embedding) |
|
relative_position_scores_key = torch.einsum("bhrd,lrd->bhlr", key_layer, positional_embedding) |
|
attention_scores = (attention_scores + relative_position_scores_query + relative_position_scores_key) |
|
|
|
attention_scores = attention_scores / math.sqrt(self.attention_head_size) |
|
if attention_mask is not None: |
|
|
|
attention_scores = attention_scores + attention_mask |
|
|
|
|
|
attention_probs = nn.Softmax(dim=-1)(attention_scores) |
|
|
|
if is_cross_attention and self.save_attention: |
|
self.save_attention_map(attention_probs) |
|
attention_probs.register_hook(self.save_attn_gradients) |
|
|
|
|
|
|
|
attention_probs_dropped = self.dropout(attention_probs) |
|
|
|
|
|
if head_mask is not None: |
|
attention_probs_dropped = attention_probs_dropped * head_mask |
|
|
|
context_layer = torch.matmul(attention_probs_dropped, value_layer) |
|
|
|
context_layer = context_layer.permute(0, 2, 1, 3).contiguous() |
|
new_context_layer_shape = context_layer.size()[:-2] + (self.all_head_size, ) |
|
context_layer = context_layer.view(*new_context_layer_shape) |
|
|
|
outputs = ((context_layer, attention_probs) if output_attentions else (context_layer, )) |
|
|
|
outputs = outputs + (past_key_value, ) |
|
return outputs |
|
|
|
|
|
class BertSelfOutput(nn.Module): |
|
def __init__(self, config): |
|
super().__init__() |
|
self.dense = nn.Linear(config.hidden_size, config.hidden_size) |
|
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps) |
|
self.dropout = nn.Dropout(config.hidden_dropout_prob) |
|
|
|
def forward(self, hidden_states, input_tensor): |
|
hidden_states = self.dense(hidden_states) |
|
hidden_states = self.dropout(hidden_states) |
|
hidden_states = self.LayerNorm(hidden_states + input_tensor) |
|
return hidden_states |
|
|
|
|
|
class BertAttention(nn.Module): |
|
def __init__(self, config, is_cross_attention=False): |
|
super().__init__() |
|
self.self = BertSelfAttention(config, is_cross_attention) |
|
self.output = BertSelfOutput(config) |
|
self.pruned_heads = set() |
|
|
|
def prune_heads(self, heads): |
|
if len(heads) == 0: |
|
return |
|
heads, index = find_pruneable_heads_and_indices( |
|
heads, |
|
self.self.num_attention_heads, |
|
self.self.attention_head_size, |
|
self.pruned_heads, |
|
) |
|
|
|
|
|
self.self.query = prune_linear_layer(self.self.query, index) |
|
self.self.key = prune_linear_layer(self.self.key, index) |
|
self.self.value = prune_linear_layer(self.self.value, index) |
|
self.output.dense = prune_linear_layer(self.output.dense, index, dim=1) |
|
|
|
|
|
self.self.num_attention_heads = self.self.num_attention_heads - len(heads) |
|
self.self.all_head_size = (self.self.attention_head_size * self.self.num_attention_heads) |
|
self.pruned_heads = self.pruned_heads.union(heads) |
|
|
|
def forward( |
|
self, |
|
hidden_states, |
|
attention_mask=None, |
|
head_mask=None, |
|
encoder_hidden_states=None, |
|
encoder_attention_mask=None, |
|
past_key_value=None, |
|
output_attentions=False, |
|
): |
|
self_outputs = self.self( |
|
hidden_states, |
|
attention_mask, |
|
head_mask, |
|
encoder_hidden_states, |
|
encoder_attention_mask, |
|
past_key_value, |
|
output_attentions, |
|
) |
|
attention_output = self.output(self_outputs[0], hidden_states) |
|
|
|
outputs = (attention_output, ) + self_outputs[1:] |
|
return outputs |
|
|
|
|
|
class BertIntermediate(nn.Module): |
|
def __init__(self, config): |
|
super().__init__() |
|
self.dense = nn.Linear(config.hidden_size, config.intermediate_size) |
|
if isinstance(config.hidden_act, str): |
|
self.intermediate_act_fn = ACT2FN[config.hidden_act] |
|
else: |
|
self.intermediate_act_fn = config.hidden_act |
|
|
|
def forward(self, hidden_states): |
|
hidden_states = self.dense(hidden_states) |
|
hidden_states = self.intermediate_act_fn(hidden_states) |
|
return hidden_states |
|
|
|
|
|
class BertOutput(nn.Module): |
|
def __init__(self, config): |
|
super().__init__() |
|
self.dense = nn.Linear(config.intermediate_size, config.hidden_size) |
|
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps) |
|
self.dropout = nn.Dropout(config.hidden_dropout_prob) |
|
|
|
def forward(self, hidden_states, input_tensor): |
|
hidden_states = self.dense(hidden_states) |
|
hidden_states = self.dropout(hidden_states) |
|
hidden_states = self.LayerNorm(hidden_states + input_tensor) |
|
return hidden_states |
|
|
|
|
|
class BertLayer(nn.Module): |
|
def __init__(self, config, layer_num): |
|
super().__init__() |
|
self.config = config |
|
self.chunk_size_feed_forward = config.chunk_size_feed_forward |
|
self.seq_len_dim = 1 |
|
self.attention = BertAttention(config) |
|
self.layer_num = layer_num |
|
if (self.config.add_cross_attention and layer_num % self.config.cross_attention_freq == 0): |
|
self.crossattention = BertAttention(config, is_cross_attention=self.config.add_cross_attention) |
|
self.has_cross_attention = True |
|
else: |
|
self.has_cross_attention = False |
|
self.intermediate = BertIntermediate(config) |
|
self.output = BertOutput(config) |
|
|
|
self.intermediate_query = BertIntermediate(config) |
|
self.output_query = BertOutput(config) |
|
|
|
def forward( |
|
self, |
|
hidden_states, |
|
attention_mask=None, |
|
head_mask=None, |
|
encoder_hidden_states=None, |
|
encoder_attention_mask=None, |
|
past_key_value=None, |
|
output_attentions=False, |
|
query_length=0, |
|
): |
|
|
|
self_attn_past_key_value = (past_key_value[:2] if past_key_value is not None else None) |
|
|
|
|
|
|
|
|
|
self_attention_outputs = self.attention( |
|
hidden_states, |
|
attention_mask, |
|
head_mask, |
|
output_attentions=output_attentions, |
|
past_key_value=self_attn_past_key_value, |
|
) |
|
|
|
|
|
|
|
attention_output = self_attention_outputs[0] |
|
outputs = self_attention_outputs[1:-1] |
|
|
|
present_key_value = self_attention_outputs[-1] |
|
|
|
|
|
if query_length > 0: |
|
query_attention_output = attention_output[:, :query_length, :] |
|
|
|
if self.has_cross_attention: |
|
assert (encoder_hidden_states is not None), "encoder_hidden_states must be given for cross-attention layers" |
|
|
|
cross_attention_outputs = self.crossattention( |
|
query_attention_output, |
|
attention_mask, |
|
head_mask, |
|
encoder_hidden_states, |
|
encoder_attention_mask, |
|
output_attentions=output_attentions, |
|
) |
|
query_attention_output = cross_attention_outputs[0] |
|
outputs = (outputs + cross_attention_outputs[1:-1]) |
|
|
|
layer_output = apply_chunking_to_forward( |
|
self.feed_forward_chunk_query, |
|
self.chunk_size_feed_forward, |
|
self.seq_len_dim, |
|
query_attention_output, |
|
) |
|
if attention_output.shape[1] > query_length: |
|
layer_output_text = apply_chunking_to_forward( |
|
self.feed_forward_chunk, |
|
self.chunk_size_feed_forward, |
|
self.seq_len_dim, |
|
attention_output[:, query_length:, :], |
|
) |
|
layer_output = torch.cat([layer_output, layer_output_text], dim=1) |
|
else: |
|
layer_output = apply_chunking_to_forward( |
|
self.feed_forward_chunk, |
|
self.chunk_size_feed_forward, |
|
self.seq_len_dim, |
|
attention_output, |
|
) |
|
outputs = (layer_output, ) + outputs |
|
|
|
outputs = outputs + (present_key_value, ) |
|
|
|
return outputs |
|
|
|
def feed_forward_chunk(self, attention_output): |
|
intermediate_output = self.intermediate(attention_output) |
|
layer_output = self.output(intermediate_output, attention_output) |
|
return layer_output |
|
|
|
def feed_forward_chunk_query(self, attention_output): |
|
intermediate_output = self.intermediate_query(attention_output) |
|
layer_output = self.output_query(intermediate_output, attention_output) |
|
return layer_output |
|
|
|
|
|
class BertEncoder(nn.Module): |
|
def __init__(self, config): |
|
super().__init__() |
|
self.config = config |
|
self.layer = nn.ModuleList([BertLayer(config, i) for i in range(config.num_hidden_layers)]) |
|
|
|
def forward( |
|
self, |
|
hidden_states, |
|
attention_mask=None, |
|
head_mask=None, |
|
encoder_hidden_states=None, |
|
encoder_attention_mask=None, |
|
past_key_values=None, |
|
use_cache=None, |
|
output_attentions=False, |
|
output_hidden_states=False, |
|
return_dict=True, |
|
query_length=0, |
|
): |
|
all_hidden_states = () if output_hidden_states else None |
|
all_self_attentions = () if output_attentions else None |
|
all_cross_attentions = (() if output_attentions and self.config.add_cross_attention else None) |
|
|
|
next_decoder_cache = () if use_cache else None |
|
|
|
for i in range(self.config.num_hidden_layers): |
|
layer_module = self.layer[i] |
|
if output_hidden_states: |
|
all_hidden_states = all_hidden_states + (hidden_states, ) |
|
|
|
layer_head_mask = head_mask[i] if head_mask is not None else None |
|
past_key_value = past_key_values[i] if past_key_values is not None else None |
|
|
|
|
|
|
|
if getattr(self.config, "gradient_checkpointing", False) and self.training: |
|
|
|
if use_cache: |
|
logger.warn("`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`...") |
|
use_cache = False |
|
|
|
def create_custom_forward(module): |
|
def custom_forward(*inputs): |
|
return module(*inputs, past_key_value, output_attentions, query_length) |
|
|
|
return custom_forward |
|
|
|
layer_outputs = torch.utils.checkpoint.checkpoint( |
|
create_custom_forward(layer_module), |
|
hidden_states, |
|
attention_mask, |
|
layer_head_mask, |
|
encoder_hidden_states, |
|
encoder_attention_mask, |
|
) |
|
else: |
|
layer_outputs = layer_module( |
|
hidden_states, |
|
attention_mask, |
|
layer_head_mask, |
|
encoder_hidden_states, |
|
encoder_attention_mask, |
|
past_key_value, |
|
output_attentions, |
|
query_length, |
|
) |
|
|
|
|
|
|
|
|
|
hidden_states = layer_outputs[0] |
|
if use_cache: |
|
next_decoder_cache += (layer_outputs[-1], ) |
|
|
|
if output_attentions: |
|
all_self_attentions = all_self_attentions + (layer_outputs[1], ) |
|
all_cross_attentions = all_cross_attentions + (layer_outputs[2], ) |
|
|
|
if output_hidden_states: |
|
all_hidden_states = all_hidden_states + (hidden_states, ) |
|
|
|
if not return_dict: |
|
return tuple(v for v in [ |
|
hidden_states, |
|
next_decoder_cache, |
|
all_hidden_states, |
|
all_self_attentions, |
|
all_cross_attentions, |
|
] if v is not None) |
|
return BaseModelOutputWithPastAndCrossAttentions( |
|
last_hidden_state=hidden_states, |
|
past_key_values=next_decoder_cache, |
|
hidden_states=all_hidden_states, |
|
attentions=all_self_attentions, |
|
cross_attentions=all_cross_attentions, |
|
) |
|
|
|
|
|
class BertPooler(nn.Module): |
|
def __init__(self, config): |
|
super().__init__() |
|
self.dense = nn.Linear(config.hidden_size, config.hidden_size) |
|
self.activation = nn.Tanh() |
|
|
|
def forward(self, hidden_states): |
|
|
|
|
|
first_token_tensor = hidden_states[:, 0] |
|
pooled_output = self.dense(first_token_tensor) |
|
pooled_output = self.activation(pooled_output) |
|
return pooled_output |
|
|
|
|
|
class BertPredictionHeadTransform(nn.Module): |
|
def __init__(self, config): |
|
super().__init__() |
|
self.dense = nn.Linear(config.hidden_size, config.hidden_size) |
|
if isinstance(config.hidden_act, str): |
|
self.transform_act_fn = ACT2FN[config.hidden_act] |
|
else: |
|
self.transform_act_fn = config.hidden_act |
|
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps) |
|
|
|
def forward(self, hidden_states): |
|
hidden_states = self.dense(hidden_states) |
|
hidden_states = self.transform_act_fn(hidden_states) |
|
hidden_states = self.LayerNorm(hidden_states) |
|
return hidden_states |
|
|
|
|
|
class BertLMPredictionHead(nn.Module): |
|
def __init__(self, config): |
|
super().__init__() |
|
self.transform = BertPredictionHeadTransform(config) |
|
|
|
|
|
|
|
self.decoder = nn.Linear(config.hidden_size, config.vocab_size, bias=False) |
|
|
|
self.bias = nn.Parameter(torch.zeros(config.vocab_size)) |
|
|
|
|
|
self.decoder.bias = self.bias |
|
|
|
def forward(self, hidden_states): |
|
hidden_states = self.transform(hidden_states) |
|
hidden_states = self.decoder(hidden_states) |
|
return hidden_states |
|
|
|
|
|
class BertOnlyMLMHead(nn.Module): |
|
def __init__(self, config): |
|
super().__init__() |
|
self.predictions = BertLMPredictionHead(config) |
|
|
|
def forward(self, sequence_output): |
|
prediction_scores = self.predictions(sequence_output) |
|
return prediction_scores |
|
|
|
|
|
class BertPreTrainedModel(PreTrainedModel): |
|
""" |
|
An abstract class to handle weights initialization and a simple interface for downloading and loading pretrained |
|
models. |
|
""" |
|
|
|
config_class = BertConfig |
|
base_model_prefix = "bert" |
|
_keys_to_ignore_on_load_missing = [r"position_ids"] |
|
|
|
def _init_weights(self, module): |
|
"""Initialize the weights""" |
|
if isinstance(module, (nn.Linear, nn.Embedding)): |
|
|
|
|
|
module.weight.data.normal_(mean=0.0, std=self.config.initializer_range) |
|
elif isinstance(module, nn.LayerNorm): |
|
module.bias.data.zero_() |
|
module.weight.data.fill_(1.0) |
|
if isinstance(module, nn.Linear) and module.bias is not None: |
|
module.bias.data.zero_() |
|
|
|
|
|
class BertModel(BertPreTrainedModel): |
|
""" |
|
The model can behave as an encoder (with only self-attention) as well as a decoder, in which case a layer of |
|
cross-attention is added between the self-attention layers, following the architecture described in `Attention is |
|
all you need <https://arxiv.org/abs/1706.03762>`__ by Ashish Vaswani, Noam Shazeer, Niki Parmar, Jakob Uszkoreit, |
|
Llion Jones, Aidan N. Gomez, Lukasz Kaiser and Illia Polosukhin. |
|
argument and :obj:`add_cross_attention` set to :obj:`True`; an :obj:`encoder_hidden_states` is then expected as an |
|
input to the forward pass. |
|
""" |
|
def __init__(self, config, add_pooling_layer=False): |
|
super().__init__(config) |
|
self.config = config |
|
|
|
self.embeddings = BertEmbeddings(config) |
|
|
|
self.encoder = BertEncoder(config) |
|
|
|
self.pooler = BertPooler(config) if add_pooling_layer else None |
|
|
|
self.init_weights() |
|
|
|
def get_input_embeddings(self): |
|
return self.embeddings.word_embeddings |
|
|
|
def set_input_embeddings(self, value): |
|
self.embeddings.word_embeddings = value |
|
|
|
def _prune_heads(self, heads_to_prune): |
|
""" |
|
Prunes heads of the model. heads_to_prune: dict of {layer_num: list of heads to prune in this layer} See base |
|
class PreTrainedModel |
|
""" |
|
for layer, heads in heads_to_prune.items(): |
|
self.encoder.layer[layer].attention.prune_heads(heads) |
|
|
|
def get_extended_attention_mask( |
|
self, |
|
attention_mask: Tensor, |
|
input_shape: Tuple[int], |
|
device: device, |
|
is_decoder: bool, |
|
is_casual: bool, |
|
has_query: bool = False, |
|
) -> Tensor: |
|
""" |
|
Makes broadcastable attention and causal masks so that future and masked tokens are ignored. |
|
|
|
Arguments: |
|
attention_mask (:obj:`torch.Tensor`): |
|
Mask with ones indicating tokens to attend to, zeros for tokens to ignore. |
|
input_shape (:obj:`Tuple[int]`): |
|
The shape of the input to the model. |
|
device: (:obj:`torch.device`): |
|
The device of the input to the model. |
|
|
|
Returns: |
|
:obj:`torch.Tensor` The extended attention mask, with a the same dtype as :obj:`attention_mask.dtype`. |
|
""" |
|
|
|
|
|
|
|
if attention_mask.dim() == 3: |
|
extended_attention_mask = attention_mask[:, None, :, :] |
|
elif attention_mask.dim() == 2: |
|
|
|
|
|
|
|
if is_decoder or is_casual: |
|
batch_size, seq_length = input_shape |
|
|
|
if not is_decoder and seq_length > 32: |
|
query_length = 32 |
|
text_length = seq_length - query_length |
|
query_ids = torch.arange(query_length, device=device) |
|
query_causal_mask = (query_ids[None, None, :].repeat(batch_size, query_length, 1) <= query_ids[None, :, |
|
None]) |
|
causal_mask = torch.ones((batch_size, seq_length, seq_length), device=device) |
|
causal_mask[:, :query_length, :query_length] = query_causal_mask |
|
|
|
|
|
|
|
else: |
|
seq_ids = torch.arange(seq_length, device=device) |
|
causal_mask = (seq_ids[None, None, :].repeat(batch_size, seq_length, 1) <= seq_ids[None, :, None]) |
|
|
|
|
|
|
|
causal_mask = causal_mask.to(attention_mask.dtype) |
|
|
|
|
|
|
|
|
|
if causal_mask.shape[1] < attention_mask.shape[1]: |
|
prefix_seq_len = attention_mask.shape[1] - causal_mask.shape[1] |
|
if has_query: |
|
causal_mask = torch.cat( |
|
[ |
|
torch.zeros( |
|
(batch_size, prefix_seq_len, seq_length), |
|
device=device, |
|
dtype=causal_mask.dtype, |
|
), |
|
causal_mask, |
|
], |
|
axis=1, |
|
) |
|
causal_mask = torch.cat( |
|
[ |
|
torch.ones( |
|
(batch_size, causal_mask.shape[1], prefix_seq_len), |
|
device=device, |
|
dtype=causal_mask.dtype, |
|
), |
|
causal_mask, |
|
], |
|
axis=-1, |
|
) |
|
|
|
|
|
extended_attention_mask = (causal_mask[:, None, :, :] * attention_mask[:, None, None, :]) |
|
|
|
|
|
else: |
|
extended_attention_mask = attention_mask[:, None, None, :] |
|
|
|
else: |
|
raise ValueError("Wrong shape for input_ids (shape {}) or attention_mask (shape {})".format( |
|
input_shape, attention_mask.shape)) |
|
|
|
|
|
|
|
|
|
|
|
|
|
extended_attention_mask = extended_attention_mask.to(dtype=self.dtype) |
|
extended_attention_mask = (1.0 - extended_attention_mask) * -10000.0 |
|
return extended_attention_mask |
|
|
|
def forward( |
|
self, |
|
input_ids=None, |
|
attention_mask=None, |
|
position_ids=None, |
|
head_mask=None, |
|
query_embeds=None, |
|
encoder_hidden_states=None, |
|
encoder_attention_mask=None, |
|
past_key_values=None, |
|
use_cache=None, |
|
output_attentions=None, |
|
output_hidden_states=None, |
|
return_dict=None, |
|
is_decoder=False, |
|
): |
|
r""" |
|
encoder_hidden_states (:obj:`torch.FloatTensor` of shape :obj:`(batch_size, sequence_length, hidden_size)`, `optional`): |
|
Sequence of hidden-states at the output of the last layer of the encoder. Used in the cross-attention if |
|
the model is configured as a decoder. |
|
encoder_attention_mask (:obj:`torch.FloatTensor` of shape :obj:`(batch_size, sequence_length)`, `optional`): |
|
Mask to avoid performing attention on the padding token indices of the encoder input. This mask is used in |
|
the cross-attention if the model is configured as a decoder. Mask values selected in ``[0, 1]``: |
|
- 1 for tokens that are **not masked**, |
|
- 0 for tokens that are **masked**. |
|
past_key_values (:obj:`tuple(tuple(torch.FloatTensor))` of length :obj:`config.n_layers` with each tuple having 4 tensors of shape :obj:`(batch_size, num_heads, sequence_length - 1, embed_size_per_head)`): |
|
Contains precomputed key and value hidden states of the attention blocks. Can be used to speed up decoding. |
|
If :obj:`past_key_values` are used, the user can optionally input only the last :obj:`decoder_input_ids` |
|
(those that don't have their past key value states given to this model) of shape :obj:`(batch_size, 1)` |
|
instead of all :obj:`decoder_input_ids` of shape :obj:`(batch_size, sequence_length)`. |
|
use_cache (:obj:`bool`, `optional`): |
|
If set to :obj:`True`, :obj:`past_key_values` key value states are returned and can be used to speed up |
|
decoding (see :obj:`past_key_values`). |
|
""" |
|
output_attentions = (output_attentions if output_attentions is not None else self.config.output_attentions) |
|
output_hidden_states = (output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states) |
|
return_dict = (return_dict if return_dict is not None else self.config.use_return_dict) |
|
|
|
|
|
|
|
if input_ids is None: |
|
assert (query_embeds is not None), "You have to specify query_embeds when input_ids is None" |
|
|
|
|
|
if query_embeds is not None and query_embeds.shape[1] == 32: |
|
is_casual = True |
|
else: |
|
is_casual = False |
|
past_key_values_length = (past_key_values[0][0].shape[2] - |
|
self.config.query_length if past_key_values is not None else 0) |
|
|
|
query_length = query_embeds.shape[1] if query_embeds is not None else 0 |
|
|
|
embedding_output = self.embeddings( |
|
input_ids=input_ids, |
|
position_ids=position_ids, |
|
query_embeds=query_embeds, |
|
past_key_values_length=past_key_values_length, |
|
) |
|
|
|
input_shape = embedding_output.size()[:-1] |
|
batch_size, seq_length = input_shape |
|
device = embedding_output.device |
|
|
|
|
|
if attention_mask is None: |
|
attention_mask = torch.ones(((batch_size, seq_length + past_key_values_length)), device=device) |
|
|
|
|
|
|
|
|
|
if is_decoder: |
|
|
|
extended_attention_mask = self.get_extended_attention_mask( |
|
attention_mask, |
|
input_ids.shape, |
|
device, |
|
is_decoder, |
|
is_casual, |
|
has_query=(query_embeds is not None), |
|
) |
|
else: |
|
extended_attention_mask = self.get_extended_attention_mask( |
|
attention_mask, |
|
input_shape, |
|
device, |
|
is_decoder, |
|
is_casual, |
|
) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
if encoder_hidden_states is not None: |
|
if type(encoder_hidden_states) == list: |
|
encoder_batch_size, encoder_sequence_length, _ = encoder_hidden_states[0].size() |
|
else: |
|
( |
|
encoder_batch_size, |
|
encoder_sequence_length, |
|
_, |
|
) = encoder_hidden_states.size() |
|
encoder_hidden_shape = (encoder_batch_size, encoder_sequence_length) |
|
|
|
if type(encoder_attention_mask) == list: |
|
encoder_extended_attention_mask = [self.invert_attention_mask(mask) for mask in encoder_attention_mask] |
|
elif encoder_attention_mask is None: |
|
encoder_attention_mask = torch.ones(encoder_hidden_shape, device=device) |
|
encoder_extended_attention_mask = self.invert_attention_mask(encoder_attention_mask) |
|
else: |
|
encoder_extended_attention_mask = self.invert_attention_mask(encoder_attention_mask) |
|
|
|
else: |
|
encoder_extended_attention_mask = None |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
head_mask = self.get_head_mask(head_mask, self.config.num_hidden_layers) |
|
|
|
|
|
encoder_outputs = self.encoder( |
|
embedding_output, |
|
attention_mask=extended_attention_mask, |
|
head_mask=head_mask, |
|
encoder_hidden_states=encoder_hidden_states, |
|
encoder_attention_mask=encoder_extended_attention_mask, |
|
past_key_values=past_key_values, |
|
use_cache=use_cache, |
|
output_attentions=output_attentions, |
|
output_hidden_states=output_hidden_states, |
|
return_dict=return_dict, |
|
query_length=query_length, |
|
) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
sequence_output = encoder_outputs[0] |
|
pooled_output = (self.pooler(sequence_output) if self.pooler is not None else None) |
|
|
|
if not return_dict: |
|
return (sequence_output, pooled_output) + encoder_outputs[1:] |
|
|
|
return BaseModelOutputWithPoolingAndCrossAttentions( |
|
last_hidden_state=sequence_output, |
|
pooler_output=pooled_output, |
|
past_key_values=encoder_outputs.past_key_values, |
|
hidden_states=encoder_outputs.hidden_states, |
|
attentions=encoder_outputs.attentions, |
|
cross_attentions=encoder_outputs.cross_attentions, |
|
) |
|
|
|
|
|
class BertLMHeadModel(BertPreTrainedModel): |
|
|
|
_keys_to_ignore_on_load_unexpected = [r"pooler"] |
|
_keys_to_ignore_on_load_missing = [r"position_ids", r"predictions.decoder.bias"] |
|
|
|
def __init__(self, config): |
|
super().__init__(config) |
|
|
|
self.bert = BertModel(config, add_pooling_layer=False) |
|
self.cls = BertOnlyMLMHead(config) |
|
|
|
self.init_weights() |
|
|
|
def get_output_embeddings(self): |
|
return self.cls.predictions.decoder |
|
|
|
def set_output_embeddings(self, new_embeddings): |
|
self.cls.predictions.decoder = new_embeddings |
|
|
|
def forward( |
|
self, |
|
input_ids=None, |
|
attention_mask=None, |
|
position_ids=None, |
|
head_mask=None, |
|
query_embeds=None, |
|
encoder_hidden_states=None, |
|
encoder_attention_mask=None, |
|
labels=None, |
|
past_key_values=None, |
|
use_cache=True, |
|
output_attentions=None, |
|
output_hidden_states=None, |
|
return_dict=None, |
|
return_logits=False, |
|
is_decoder=True, |
|
reduction="mean", |
|
): |
|
r""" |
|
encoder_hidden_states (:obj:`torch.FloatTensor` of shape :obj:`(batch_size, sequence_length, hidden_size)`, `optional`): |
|
Sequence of hidden-states at the output of the last layer of the encoder. Used in the cross-attention if |
|
the model is configured as a decoder. |
|
encoder_attention_mask (:obj:`torch.FloatTensor` of shape :obj:`(batch_size, sequence_length)`, `optional`): |
|
Mask to avoid performing attention on the padding token indices of the encoder input. This mask is used in |
|
the cross-attention if the model is configured as a decoder. Mask values selected in ``[0, 1]``: |
|
- 1 for tokens that are **not masked**, |
|
- 0 for tokens that are **masked**. |
|
labels (:obj:`torch.LongTensor` of shape :obj:`(batch_size, sequence_length)`, `optional`): |
|
Labels for computing the left-to-right language modeling loss (next word prediction). Indices should be in |
|
``[-100, 0, ..., config.vocab_size]`` (see ``input_ids`` docstring) Tokens with indices set to ``-100`` are |
|
ignored (masked), the loss is only computed for the tokens with labels n ``[0, ..., config.vocab_size]`` |
|
past_key_values (:obj:`tuple(tuple(torch.FloatTensor))` of length :obj:`config.n_layers` with each tuple having 4 tensors of shape :obj:`(batch_size, num_heads, sequence_length - 1, embed_size_per_head)`): |
|
Contains precomputed key and value hidden states of the attention blocks. Can be used to speed up decoding. |
|
If :obj:`past_key_values` are used, the user can optionally input only the last :obj:`decoder_input_ids` |
|
(those that don't have their past key value states given to this model) of shape :obj:`(batch_size, 1)` |
|
instead of all :obj:`decoder_input_ids` of shape :obj:`(batch_size, sequence_length)`. |
|
use_cache (:obj:`bool`, `optional`): |
|
If set to :obj:`True`, :obj:`past_key_values` key value states are returned and can be used to speed up |
|
decoding (see :obj:`past_key_values`). |
|
Returns: |
|
Example:: |
|
>>> from transformers import BertTokenizer, BertLMHeadModel, BertConfig |
|
>>> import torch |
|
>>> tokenizer = BertTokenizer.from_pretrained('bert-base-cased') |
|
>>> config = BertConfig.from_pretrained("bert-base-cased") |
|
>>> model = BertLMHeadModel.from_pretrained('bert-base-cased', config=config) |
|
>>> inputs = tokenizer("Hello, my dog is cute", return_tensors="pt") |
|
>>> outputs = model(**inputs) |
|
>>> prediction_logits = outputs.logits |
|
""" |
|
return_dict = (return_dict if return_dict is not None else self.config.use_return_dict) |
|
if labels is not None: |
|
use_cache = False |
|
if past_key_values is not None: |
|
query_embeds = None |
|
|
|
|
|
outputs = self.bert( |
|
input_ids, |
|
attention_mask=attention_mask, |
|
position_ids=position_ids, |
|
head_mask=head_mask, |
|
query_embeds=query_embeds, |
|
encoder_hidden_states=encoder_hidden_states, |
|
encoder_attention_mask=encoder_attention_mask, |
|
past_key_values=past_key_values, |
|
use_cache=use_cache, |
|
output_attentions=output_attentions, |
|
output_hidden_states=output_hidden_states, |
|
return_dict=return_dict, |
|
is_decoder=is_decoder, |
|
) |
|
|
|
sequence_output = outputs[0] |
|
if query_embeds is not None: |
|
sequence_output = outputs[0][:, query_embeds.shape[1]:, :] |
|
|
|
prediction_scores = self.cls(sequence_output) |
|
|
|
if return_logits: |
|
return prediction_scores[:, :-1, :].contiguous() |
|
|
|
lm_loss = None |
|
if labels is not None: |
|
|
|
shifted_prediction_scores = prediction_scores[:, :-1, :].contiguous() |
|
labels = labels[:, 1:].contiguous() |
|
loss_fct = CrossEntropyLoss(reduction=reduction, label_smoothing=0.1) |
|
lm_loss = loss_fct( |
|
shifted_prediction_scores.view(-1, self.config.vocab_size), |
|
labels.view(-1), |
|
) |
|
if reduction == "none": |
|
lm_loss = lm_loss.view(prediction_scores.size(0), -1).sum(1) |
|
|
|
if not return_dict: |
|
output = (prediction_scores, ) + outputs[2:] |
|
return ((lm_loss, ) + output) if lm_loss is not None else output |
|
|
|
return CausalLMOutputWithCrossAttentions( |
|
loss=lm_loss, |
|
logits=prediction_scores, |
|
past_key_values=outputs.past_key_values, |
|
hidden_states=outputs.hidden_states, |
|
attentions=outputs.attentions, |
|
cross_attentions=outputs.cross_attentions, |
|
) |
|
|
|
def prepare_inputs_for_generation(self, input_ids, query_embeds, past=None, attention_mask=None, **model_kwargs): |
|
|
|
if attention_mask is None: |
|
attention_mask = input_ids.new_ones(input_ids.shape) |
|
query_mask = input_ids.new_ones(query_embeds.shape[:-1]) |
|
attention_mask = torch.cat([query_mask, attention_mask], dim=-1) |
|
|
|
|
|
if past is not None: |
|
input_ids = input_ids[:, -1:] |
|
|
|
return { |
|
"input_ids": input_ids, |
|
"query_embeds": query_embeds, |
|
"attention_mask": attention_mask, |
|
"past_key_values": past, |
|
"encoder_hidden_states": model_kwargs.get("encoder_hidden_states", None), |
|
"encoder_attention_mask": model_kwargs.get("encoder_attention_mask", None), |
|
"is_decoder": True, |
|
} |
|
|
|
def _reorder_cache(self, past, beam_idx): |
|
reordered_past = () |
|
for layer_past in past: |
|
reordered_past += (tuple(past_state.index_select(0, beam_idx) for past_state in layer_past), ) |
|
return reordered_past |
|
|
|
|
|
class BertForMaskedLM(BertPreTrainedModel): |
|
|
|
_keys_to_ignore_on_load_unexpected = [r"pooler"] |
|
_keys_to_ignore_on_load_missing = [r"position_ids", r"predictions.decoder.bias"] |
|
|
|
def __init__(self, config): |
|
super().__init__(config) |
|
|
|
self.bert = BertModel(config, add_pooling_layer=False) |
|
self.cls = BertOnlyMLMHead(config) |
|
|
|
self.init_weights() |
|
|
|
def get_output_embeddings(self): |
|
return self.cls.predictions.decoder |
|
|
|
def set_output_embeddings(self, new_embeddings): |
|
self.cls.predictions.decoder = new_embeddings |
|
|
|
def forward( |
|
self, |
|
input_ids=None, |
|
attention_mask=None, |
|
position_ids=None, |
|
head_mask=None, |
|
query_embeds=None, |
|
encoder_hidden_states=None, |
|
encoder_attention_mask=None, |
|
labels=None, |
|
output_attentions=None, |
|
output_hidden_states=None, |
|
return_dict=None, |
|
return_logits=False, |
|
is_decoder=False, |
|
): |
|
r""" |
|
labels (:obj:`torch.LongTensor` of shape :obj:`(batch_size, sequence_length)`, `optional`): |
|
Labels for computing the masked language modeling loss. Indices should be in ``[-100, 0, ..., |
|
config.vocab_size]`` (see ``input_ids`` docstring) Tokens with indices set to ``-100`` are ignored |
|
(masked), the loss is only computed for the tokens with labels in ``[0, ..., config.vocab_size]`` |
|
""" |
|
|
|
return_dict = (return_dict if return_dict is not None else self.config.use_return_dict) |
|
|
|
outputs = self.bert( |
|
input_ids, |
|
attention_mask=attention_mask, |
|
position_ids=position_ids, |
|
head_mask=head_mask, |
|
query_embeds=query_embeds, |
|
encoder_hidden_states=encoder_hidden_states, |
|
encoder_attention_mask=encoder_attention_mask, |
|
output_attentions=output_attentions, |
|
output_hidden_states=output_hidden_states, |
|
return_dict=return_dict, |
|
is_decoder=is_decoder, |
|
) |
|
|
|
if query_embeds is not None: |
|
sequence_output = outputs[0][:, query_embeds.shape[1]:, :] |
|
prediction_scores = self.cls(sequence_output) |
|
|
|
if return_logits: |
|
return prediction_scores |
|
|
|
masked_lm_loss = None |
|
if labels is not None: |
|
loss_fct = CrossEntropyLoss() |
|
masked_lm_loss = loss_fct(prediction_scores.view(-1, self.config.vocab_size), labels.view(-1)) |
|
|
|
if not return_dict: |
|
output = (prediction_scores, ) + outputs[2:] |
|
return (((masked_lm_loss, ) + output) if masked_lm_loss is not None else output) |
|
|
|
return MaskedLMOutput( |
|
loss=masked_lm_loss, |
|
logits=prediction_scores, |
|
hidden_states=outputs.hidden_states, |
|
attentions=outputs.attentions, |
|
) |
|
|
|
class Mlp(nn.Module): |
|
"""MLP as used in Vision Transformer, MLP-Mixer and related networks""" |
|
def __init__( |
|
self, |
|
in_features, |
|
hidden_features=None, |
|
out_features=None, |
|
act_layer=nn.GELU, |
|
drop=0.0, |
|
): |
|
super().__init__() |
|
out_features = out_features or in_features |
|
hidden_features = hidden_features or in_features |
|
self.fc1 = nn.Linear(in_features, hidden_features) |
|
self.act = act_layer() |
|
self.fc2 = nn.Linear(hidden_features, out_features) |
|
self.drop = nn.Dropout(drop) |
|
|
|
def forward(self, x): |
|
x = self.fc1(x) |
|
x = self.act(x) |
|
x = self.drop(x) |
|
x = self.fc2(x) |
|
x = self.drop(x) |
|
return x |
|
|
|
|
|
class Attention(nn.Module): |
|
def __init__( |
|
self, |
|
dim, |
|
num_heads=8, |
|
qkv_bias=False, |
|
qk_scale=None, |
|
attn_drop=0.0, |
|
proj_drop=0.0, |
|
): |
|
super().__init__() |
|
self.num_heads = num_heads |
|
head_dim = dim // num_heads |
|
|
|
self.scale = qk_scale or head_dim**-0.5 |
|
self.qkv = nn.Linear(dim, dim * 3, bias=qkv_bias) |
|
self.attn_drop = nn.Dropout(attn_drop) |
|
self.proj = nn.Linear(dim, dim) |
|
self.proj_drop = nn.Dropout(proj_drop) |
|
self.attn_gradients = None |
|
self.attention_map = None |
|
|
|
def save_attn_gradients(self, attn_gradients): |
|
self.attn_gradients = attn_gradients |
|
|
|
def get_attn_gradients(self): |
|
return self.attn_gradients |
|
|
|
def save_attention_map(self, attention_map): |
|
self.attention_map = attention_map |
|
|
|
def get_attention_map(self): |
|
return self.attention_map |
|
|
|
def forward(self, x, register_hook=False): |
|
B, N, C = x.shape |
|
qkv = (self.qkv(x).reshape(B, N, 3, self.num_heads, C // self.num_heads).permute(2, 0, 3, 1, 4)) |
|
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) |
|
|
|
if register_hook: |
|
self.save_attention_map(attn) |
|
attn.register_hook(self.save_attn_gradients) |
|
|
|
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=4.0, |
|
qkv_bias=False, |
|
qk_scale=None, |
|
drop=0.0, |
|
attn_drop=0.0, |
|
drop_path=0.0, |
|
act_layer=nn.GELU, |
|
norm_layer=nn.LayerNorm, |
|
use_grad_checkpointing=False, |
|
): |
|
super().__init__() |
|
self.norm1 = norm_layer(dim) |
|
self.attn = Attention( |
|
dim, |
|
num_heads=num_heads, |
|
qkv_bias=qkv_bias, |
|
qk_scale=qk_scale, |
|
attn_drop=attn_drop, |
|
proj_drop=drop, |
|
) |
|
|
|
self.drop_path = DropPath(drop_path) if drop_path > 0.0 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, register_hook=False): |
|
x = x + self.drop_path(self.attn(self.norm1(x), register_hook=register_hook)) |
|
x = x + self.drop_path(self.mlp(self.norm2(x))) |
|
return x |
|
|
|
|
|
class VisionTransformer(nn.Module): |
|
"""Vision Transformer |
|
A PyTorch impl of : `An Image is Worth 16x16 Words: Transformers for Image Recognition at Scale` - |
|
https://arxiv.org/abs/2010.11929 |
|
""" |
|
def __init__( |
|
self, |
|
img_size=224, |
|
patch_size=16, |
|
in_chans=3, |
|
num_classes=1000, |
|
embed_dim=768, |
|
depth=12, |
|
num_heads=12, |
|
mlp_ratio=4.0, |
|
qkv_bias=True, |
|
qk_scale=None, |
|
representation_size=None, |
|
drop_rate=0.0, |
|
attn_drop_rate=0.0, |
|
drop_path_rate=0.0, |
|
norm_layer=None, |
|
use_grad_checkpointing=False, |
|
ckpt_layer=0, |
|
): |
|
""" |
|
Args: |
|
img_size (int, tuple): input image size |
|
patch_size (int, tuple): patch size |
|
in_chans (int): number of input channels |
|
num_classes (int): number of classes for classification head |
|
embed_dim (int): embedding dimension |
|
depth (int): depth of transformer |
|
num_heads (int): number of attention heads |
|
mlp_ratio (int): ratio of mlp hidden dim to embedding dim |
|
qkv_bias (bool): enable bias for qkv if True |
|
qk_scale (float): override default qk scale of head_dim ** -0.5 if set |
|
representation_size (Optional[int]): enable and set representation layer (pre-logits) to this value if set |
|
drop_rate (float): dropout rate |
|
attn_drop_rate (float): attention dropout rate |
|
drop_path_rate (float): stochastic depth rate |
|
norm_layer: (nn.Module): normalization layer |
|
""" |
|
super().__init__() |
|
self.num_features = (self.embed_dim) = embed_dim |
|
norm_layer = norm_layer or partial(nn.LayerNorm, eps=1e-6) |
|
|
|
self.patch_embed = PatchEmbed( |
|
img_size=img_size, |
|
patch_size=patch_size, |
|
in_chans=in_chans, |
|
embed_dim=embed_dim, |
|
) |
|
|
|
num_patches = self.patch_embed.num_patches |
|
|
|
self.cls_token = nn.Parameter(torch.zeros(1, 1, embed_dim)) |
|
self.pos_embed = nn.Parameter(torch.zeros(1, num_patches + 1, embed_dim)) |
|
self.pos_drop = nn.Dropout(p=drop_rate) |
|
|
|
dpr = [x.item() for x in torch.linspace(0, drop_path_rate, depth)] |
|
self.blocks = nn.ModuleList([ |
|
Block( |
|
dim=embed_dim, |
|
num_heads=num_heads, |
|
mlp_ratio=mlp_ratio, |
|
qkv_bias=qkv_bias, |
|
qk_scale=qk_scale, |
|
drop=drop_rate, |
|
attn_drop=attn_drop_rate, |
|
drop_path=dpr[i], |
|
norm_layer=norm_layer, |
|
use_grad_checkpointing=(use_grad_checkpointing and i >= depth - ckpt_layer), |
|
) for i in range(depth) |
|
]) |
|
self.norm = norm_layer(embed_dim) |
|
|
|
trunc_normal_(self.pos_embed, std=0.02) |
|
trunc_normal_(self.cls_token, std=0.02) |
|
self.apply(self._init_weights) |
|
|
|
def _init_weights(self, m): |
|
if isinstance(m, nn.Linear): |
|
trunc_normal_(m.weight, std=0.02) |
|
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) |
|
|
|
@torch.jit.ignore |
|
def no_weight_decay(self): |
|
return {"pos_embed", "cls_token"} |
|
|
|
def forward(self, x, register_blk=-1): |
|
B = x.shape[0] |
|
x = self.patch_embed(x) |
|
|
|
cls_tokens = self.cls_token.expand(B, -1, -1) |
|
x = torch.cat((cls_tokens, x), dim=1) |
|
|
|
x = x + self.pos_embed[:, :x.size(1), :] |
|
x = self.pos_drop(x) |
|
|
|
for i, blk in enumerate(self.blocks): |
|
x = blk(x, register_blk == i) |
|
x = self.norm(x) |
|
|
|
return x |
|
|
|
|
|
@torch.no_grad() |
|
def _load_weights(model: VisionTransformer, checkpoint_path: str, prefix: str = ""): |
|
"""Load weights from .npz checkpoints for official Google Brain Flax implementation""" |
|
import numpy as np |
|
|
|
def _n2p(w, t=True): |
|
if w.ndim == 4 and w.shape[0] == w.shape[1] == w.shape[2] == 1: |
|
w = w.flatten() |
|
if t: |
|
if w.ndim == 4: |
|
w = w.transpose([3, 2, 0, 1]) |
|
elif w.ndim == 3: |
|
w = w.transpose([2, 0, 1]) |
|
elif w.ndim == 2: |
|
w = w.transpose([1, 0]) |
|
return torch.from_numpy(w) |
|
|
|
w = np.load(checkpoint_path) |
|
if not prefix and "opt/target/embedding/kernel" in w: |
|
prefix = "opt/target/" |
|
|
|
if hasattr(model.patch_embed, "backbone"): |
|
|
|
backbone = model.patch_embed.backbone |
|
stem_only = not hasattr(backbone, "stem") |
|
stem = backbone if stem_only else backbone.stem |
|
stem.conv.weight.copy_(adapt_input_conv(stem.conv.weight.shape[1], _n2p(w[f"{prefix}conv_root/kernel"]))) |
|
stem.norm.weight.copy_(_n2p(w[f"{prefix}gn_root/scale"])) |
|
stem.norm.bias.copy_(_n2p(w[f"{prefix}gn_root/bias"])) |
|
if not stem_only: |
|
for i, stage in enumerate(backbone.stages): |
|
for j, block in enumerate(stage.blocks): |
|
bp = f"{prefix}block{i + 1}/unit{j + 1}/" |
|
for r in range(3): |
|
getattr(block, f"conv{r + 1}").weight.copy_(_n2p(w[f"{bp}conv{r + 1}/kernel"])) |
|
getattr(block, f"norm{r + 1}").weight.copy_(_n2p(w[f"{bp}gn{r + 1}/scale"])) |
|
getattr(block, f"norm{r + 1}").bias.copy_(_n2p(w[f"{bp}gn{r + 1}/bias"])) |
|
if block.downsample is not None: |
|
block.downsample.conv.weight.copy_(_n2p(w[f"{bp}conv_proj/kernel"])) |
|
block.downsample.norm.weight.copy_(_n2p(w[f"{bp}gn_proj/scale"])) |
|
block.downsample.norm.bias.copy_(_n2p(w[f"{bp}gn_proj/bias"])) |
|
embed_conv_w = _n2p(w[f"{prefix}embedding/kernel"]) |
|
else: |
|
embed_conv_w = adapt_input_conv(model.patch_embed.proj.weight.shape[1], _n2p(w[f"{prefix}embedding/kernel"])) |
|
model.patch_embed.proj.weight.copy_(embed_conv_w) |
|
model.patch_embed.proj.bias.copy_(_n2p(w[f"{prefix}embedding/bias"])) |
|
model.cls_token.copy_(_n2p(w[f"{prefix}cls"], t=False)) |
|
pos_embed_w = _n2p(w[f"{prefix}Transformer/posembed_input/pos_embedding"], t=False) |
|
if pos_embed_w.shape != model.pos_embed.shape: |
|
pos_embed_w = resize_pos_embed( |
|
pos_embed_w, |
|
model.pos_embed, |
|
getattr(model, "num_tokens", 1), |
|
model.patch_embed.grid_size, |
|
) |
|
model.pos_embed.copy_(pos_embed_w) |
|
model.norm.weight.copy_(_n2p(w[f"{prefix}Transformer/encoder_norm/scale"])) |
|
model.norm.bias.copy_(_n2p(w[f"{prefix}Transformer/encoder_norm/bias"])) |
|
|
|
|
|
|
|
|
|
|
|
|
|
for i, block in enumerate(model.blocks.children()): |
|
block_prefix = f"{prefix}Transformer/encoderblock_{i}/" |
|
mha_prefix = block_prefix + "MultiHeadDotProductAttention_1/" |
|
block.norm1.weight.copy_(_n2p(w[f"{block_prefix}LayerNorm_0/scale"])) |
|
block.norm1.bias.copy_(_n2p(w[f"{block_prefix}LayerNorm_0/bias"])) |
|
block.attn.qkv.weight.copy_( |
|
torch.cat([_n2p(w[f"{mha_prefix}{n}/kernel"], t=False).flatten(1).T for n in ("query", "key", "value")])) |
|
block.attn.qkv.bias.copy_( |
|
torch.cat([_n2p(w[f"{mha_prefix}{n}/bias"], t=False).reshape(-1) for n in ("query", "key", "value")])) |
|
block.attn.proj.weight.copy_(_n2p(w[f"{mha_prefix}out/kernel"]).flatten(1)) |
|
block.attn.proj.bias.copy_(_n2p(w[f"{mha_prefix}out/bias"])) |
|
for r in range(2): |
|
getattr(block.mlp, f"fc{r + 1}").weight.copy_(_n2p(w[f"{block_prefix}MlpBlock_3/Dense_{r}/kernel"])) |
|
getattr(block.mlp, f"fc{r + 1}").bias.copy_(_n2p(w[f"{block_prefix}MlpBlock_3/Dense_{r}/bias"])) |
|
block.norm2.weight.copy_(_n2p(w[f"{block_prefix}LayerNorm_2/scale"])) |
|
block.norm2.bias.copy_(_n2p(w[f"{block_prefix}LayerNorm_2/bias"])) |
|
|
|
|
|
def resize_pos_embed(posemb, posemb_new, num_tokens=1, gs_new=()): |
|
|
|
|
|
print("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))) |
|
if not len(gs_new): |
|
gs_new = [int(math.sqrt(ntok_new))] * 2 |
|
assert len(gs_new) >= 2 |
|
print("Position embedding grid-size from %s to %s", [gs_old, 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, mode="bicubic", align_corners=False) |
|
posemb_grid = posemb_grid.permute(0, 2, 3, 1).reshape(1, gs_new[0] * gs_new[1], -1) |
|
posemb = torch.cat([posemb_tok, posemb_grid], dim=1) |
|
return |
|
|
|
|
|
def interpolate_pos_embed(pos_embed_checkpoint, visual_encoder): |
|
|
|
embedding_size = pos_embed_checkpoint.shape[-1] |
|
num_patches = visual_encoder.patch_embed.num_patches |
|
num_extra_tokens = visual_encoder.pos_embed.shape[-2] - num_patches |
|
|
|
orig_size = int((pos_embed_checkpoint.shape[-2] - num_extra_tokens)**0.5) |
|
|
|
new_size = int(num_patches**0.5) |
|
|
|
if orig_size != new_size: |
|
|
|
extra_tokens = pos_embed_checkpoint[:, :num_extra_tokens] |
|
|
|
pos_tokens = pos_embed_checkpoint[:, num_extra_tokens:] |
|
pos_tokens = pos_tokens.reshape(-1, orig_size, orig_size, embedding_size).permute(0, 3, 1, 2) |
|
pos_tokens = torch.nn.functional.interpolate(pos_tokens, size=(new_size, new_size), mode="bicubic", align_corners=False) |
|
pos_tokens = pos_tokens.permute(0, 2, 3, 1).flatten(1, 2) |
|
new_pos_embed = torch.cat((extra_tokens, pos_tokens), dim=1) |
|
print("reshape position embedding from %d to %d" % (orig_size**2, new_size**2)) |
|
|
|
return new_pos_embed |
|
else: |
|
return pos_embed_checkpoint |
|
|
|
|
|
class Blip2Base(PreTrainedModel): |
|
config_class = BertConfig |
|
|
|
def __init__(self, config): |
|
super().__init__(config) |
|
|
|
@property |
|
def device(self): |
|
return list(self.parameters())[0].device |
|
|
|
@classmethod |
|
def init_tokenizer(cls, truncation_side="right"): |
|
tokenizer = BertTokenizer.from_pretrained("bert-base-uncased", truncation_side=truncation_side) |
|
tokenizer.add_special_tokens({"bos_token": "[DEC]"}) |
|
return tokenizer |
|
|
|
@classmethod |
|
def init_Qformer(cls, encoder_config, num_query_token, vision_width, cross_attention_freq=2, cache_dir=""): |
|
|
|
encoder_config = BertConfig.from_pretrained("bert-base-uncased") |
|
encoder_config.encoder_width = vision_width |
|
|
|
encoder_config.add_cross_attention = True |
|
encoder_config.cross_attention_freq = cross_attention_freq |
|
encoder_config.query_length = num_query_token |
|
Qformer = BertLMHeadModel(encoder_config) |
|
query_tokens = nn.Parameter(torch.zeros(1, num_query_token, encoder_config.hidden_size)) |
|
query_tokens.data.normal_(mean=0.0, std=encoder_config.initializer_range) |
|
return Qformer, query_tokens |
|
|
|
|
|
|
|
class VectorQuantizer2(nn.Module): |
|
""" |
|
Improved version over VectorQuantizer, can be used as a drop-in replacement. Mostly |
|
avoids costly matrix multiplications and allows for post-hoc remapping of indices. |
|
""" |
|
|
|
|
|
|
|
|
|
def __init__(self, n_e, e_dim, beta, remap=None, unknown_index="random", sane_index_shape=False, legacy=True): |
|
super().__init__() |
|
self.n_e = n_e |
|
self.e_dim = e_dim |
|
self.beta = beta |
|
self.legacy = legacy |
|
|
|
self.embedding = nn.Embedding(self.n_e, self.e_dim) |
|
self.embedding.weight.data.uniform_(-1.0 / self.n_e, 1.0 / self.n_e) |
|
|
|
self.remap = remap |
|
if self.remap is not None: |
|
self.register_buffer("used", torch.tensor(np.load(self.remap))) |
|
self.re_embed = self.used.shape[0] |
|
self.unknown_index = unknown_index |
|
if self.unknown_index == "extra": |
|
self.unknown_index = self.re_embed |
|
self.re_embed = self.re_embed + 1 |
|
print(f"Remapping {self.n_e} indices to {self.re_embed} indices. " |
|
f"Using {self.unknown_index} for unknown indices.") |
|
else: |
|
self.re_embed = n_e |
|
|
|
self.sane_index_shape = sane_index_shape |
|
|
|
def remap_to_used(self, inds): |
|
ishape = inds.shape |
|
assert len(ishape) > 1 |
|
inds = inds.reshape(ishape[0], -1) |
|
used = self.used.to(inds) |
|
match = (inds[:, :, None] == used[None, None, ...]).long() |
|
new = match.argmax(-1) |
|
unknown = match.sum(2) < 1 |
|
if self.unknown_index == "random": |
|
new[unknown] = torch.randint(0, self.re_embed, size=new[unknown].shape).to(device=new.device) |
|
else: |
|
new[unknown] = self.unknown_index |
|
return new.reshape(ishape) |
|
|
|
def unmap_to_all(self, inds): |
|
ishape = inds.shape |
|
assert len(ishape) > 1 |
|
inds = inds.reshape(ishape[0], -1) |
|
used = self.used.to(inds) |
|
if self.re_embed > self.used.shape[0]: |
|
inds[inds >= self.used.shape[0]] = 0 |
|
back = torch.gather(used[None, :][inds.shape[0] * [0], :], 1, inds) |
|
return back.reshape(ishape) |
|
|
|
|
|
|
|
|
|
def forward(self, z, temp=None, rescale_logits=False, return_logits=False): |
|
assert temp is None or temp == 1.0, "Only for interface compatible with Gumbel" |
|
assert rescale_logits is False, "Only for interface compatible with Gumbel" |
|
assert return_logits is False, "Only for interface compatible with Gumbel" |
|
|
|
|
|
bz = z.shape[0] |
|
z_flattened = z.view(-1, self.e_dim) |
|
|
|
|
|
|
|
d = torch.sum(z_flattened ** 2, dim=1, keepdim=True) + \ |
|
torch.sum(self.embedding.weight**2, dim=1) - 2 * \ |
|
torch.einsum('bd,dn->bn', z_flattened, rearrange(self.embedding.weight, 'n d -> d n')) |
|
|
|
min_encoding_indices = torch.argmin(d, dim=1) |
|
z_q = self.embedding(min_encoding_indices).view(z.shape) |
|
perplexity = None |
|
min_encodings = None |
|
|
|
|
|
if not self.legacy: |
|
loss = self.beta * torch.mean((z_q.detach() - z)**2) + torch.mean((z_q - z.detach())**2) |
|
else: |
|
loss = torch.mean((z_q.detach() - z)**2) + self.beta * torch.mean((z_q - z.detach())**2) |
|
|
|
|
|
z_q = z + (z_q - z).detach() |
|
|
|
|
|
|
|
z_q = z_q.reshape(bz, -1, z_q.shape[-1]) |
|
if self.remap is not None: |
|
min_encoding_indices = min_encoding_indices.reshape(z.shape[0], -1) |
|
min_encoding_indices = self.remap_to_used(min_encoding_indices) |
|
min_encoding_indices = min_encoding_indices.reshape(-1, 1) |
|
|
|
if self.sane_index_shape: |
|
min_encoding_indices = min_encoding_indices.reshape(z_q.shape[0], z_q.shape[2], z_q.shape[3]) |
|
|
|
return z_q, loss, min_encoding_indices |
|
|
|
def get_codebook_entry(self, indices, shape=None): |
|
|
|
if self.remap is not None: |
|
indices = indices.reshape(shape[0], -1) |
|
indices = self.unmap_to_all(indices) |
|
indices = indices.reshape(-1) |
|
|
|
|
|
z_q = self.embedding(indices) |
|
|
|
if shape is not None: |
|
z_q = z_q.view(shape) |
|
|
|
z_q = z_q.permute(0, 3, 1, 2).contiguous() |
|
|
|
return z_q |
|
|
|
|
|
class Blip2QformerQuantizer(Blip2Base): |
|
""" |
|
BLIP2 first-stage model with Q-former and ViT. |
|
Supported model types: |
|
- pretrained: pretrained model with vit-g |
|
- pretrain_vitL: pretrained model with vit-large |
|
- coco: fintuned model on coco |
|
Usage: |
|
>>> from lavis.models import load_model |
|
>>> model = load_model("blip2", "pretrain") |
|
""" |
|
|
|
PRETRAINED_MODEL_CONFIG_DICT = { |
|
"pretrain": "configs/models/blip2/blip2_pretrain.yaml", |
|
"pretrain_vitL": "configs/models/blip2/blip2_pretrain_vitL.yaml", |
|
"coco": "configs/models/blip2/blip2_coco.yaml", |
|
} |
|
|
|
def __init__(self, |
|
config, |
|
img_size=224, |
|
drop_path_rate=0, |
|
use_grad_checkpoint=False, |
|
freeze_vit=True, |
|
num_query_token=32, |
|
cross_attention_freq=2, |
|
embed_dim=256, |
|
max_txt_len=32, |
|
codebook_embed_dim=32, |
|
n_embed=8192, |
|
recon_s=True, |
|
blocks_for_image=True, |
|
decode_depth=4, |
|
use_recon_s_for_image=False, |
|
image_features_dim=1024, |
|
visual_encoder_num_features=1408, |
|
cache_dir="./"): |
|
super().__init__(config) |
|
|
|
self.tokenizer = self.init_tokenizer() |
|
|
|
self.codebook_embed_dim = codebook_embed_dim |
|
self.n_embed = n_embed |
|
self.recon_s = recon_s |
|
self.blocks_for_image = blocks_for_image |
|
self.use_recon_s_for_image = use_recon_s_for_image |
|
self.depth = decode_depth |
|
self.image_features_dim = image_features_dim |
|
|
|
self.Qformer, self.query_tokens = self.init_Qformer(config, num_query_token, visual_encoder_num_features, cache_dir=cache_dir) |
|
|
|
self.Qformer.cls = None |
|
self.Qformer.bert.embeddings.word_embeddings = None |
|
self.Qformer.bert.embeddings.position_embeddings = None |
|
for layer in self.Qformer.bert.encoder.layer: |
|
layer.output = None |
|
layer.intermediate = None |
|
|
|
for name, param in self.Qformer.named_parameters(): |
|
param.requires_grad = False |
|
self.query_tokens.requires_grad = False |
|
|
|
self.quantize = VectorQuantizer2(n_embed, codebook_embed_dim, beta=0.25, remap=None, sane_index_shape=False) |
|
|
|
self.encode_task_layer = nn.Sequential( |
|
nn.Linear(self.Qformer.config.hidden_size, self.Qformer.config.hidden_size), |
|
nn.Tanh(), |
|
nn.Linear(self.Qformer.config.hidden_size, codebook_embed_dim) |
|
) |
|
|
|
self.decode_task_layer = nn.Sequential( |
|
nn.Linear(codebook_embed_dim, codebook_embed_dim), |
|
nn.Tanh(), |
|
nn.Linear(codebook_embed_dim, self.Qformer.config.hidden_size) |
|
) |
|
|
|
self.quantize = self.quantize.eval() |
|
self.quantize.training = False |
|
for name, param in self.named_parameters(): |
|
if 'quantize' in name or 'encode_task_layer' in name or 'decode_task_layer' in name: |
|
|
|
param.requires_grad = False |
|
|
|
if self.recon_s: |
|
self.pos_embed = nn.Parameter(torch.zeros(1, num_query_token, self.Qformer.config.hidden_size)) |
|
self.blocks = nn.ModuleList([ |
|
Block(dim=self.Qformer.config.hidden_size, |
|
num_heads=12, |
|
mlp_ratio=4.0, |
|
qkv_bias=True, |
|
qk_scale=None, |
|
drop=0.0, |
|
attn_drop=0.0, |
|
drop_path=0.0, |
|
norm_layer=partial(nn.LayerNorm, eps=1e-6)) for i in range(self.depth) |
|
]) |
|
|
|
if self.blocks_for_image: |
|
self.pos_embed_image = nn.Parameter(torch.zeros(1, num_query_token, self.Qformer.config.hidden_size)) |
|
self.blocks_image = nn.ModuleList([ |
|
Block(dim=self.Qformer.config.hidden_size, |
|
num_heads=12, |
|
mlp_ratio=4.0, |
|
qkv_bias=True, |
|
qk_scale=None, |
|
drop=0.0, |
|
attn_drop=0.0, |
|
drop_path=0.0, |
|
norm_layer=partial(nn.LayerNorm, eps=1e-6)) for i in range(self.depth) |
|
]) |
|
|
|
self.image_down = nn.Sequential( |
|
nn.Linear(self.Qformer.config.hidden_size, 256, bias=False), |
|
nn.ReLU(), |
|
nn.Linear(256, 128, bias=False), |
|
nn.ReLU(), |
|
nn.Linear(128, 32, bias=False), |
|
) |
|
self.distill_image_proj = nn.Linear(num_query_token * 32, image_features_dim) |
|
|
|
def get_codebook_indices_only(self, visual_encoder, image): |
|
with torch.no_grad(): |
|
image_embeds = visual_encoder.ln_vision(visual_encoder(image)) |
|
image_atts = torch.ones(image_embeds.size()[:-1], dtype=torch.long).to(image.device) |
|
query_tokens = self.query_tokens.expand(image_embeds.shape[0], -1, -1) |
|
query_output = self.Qformer.bert( |
|
query_embeds=query_tokens, |
|
encoder_hidden_states=image_embeds, |
|
encoder_attention_mask=image_atts, |
|
return_dict=True, |
|
) |
|
|
|
query_output_down = self.encode_task_layer(query_output.last_hidden_state) |
|
quant, loss_embed, embed_ind = self.quantize(query_output_down) |
|
embed_ind = embed_ind.reshape(quant.shape[0], -1) |
|
|
|
return embed_ind |
|
|
|
def get_codebook_indices(self, visual_encoder, image): |
|
with torch.no_grad(): |
|
image_embeds = visual_encoder.ln_vision(visual_encoder(image)) |
|
image_atts = torch.ones(image_embeds.size()[:-1], dtype=torch.long).to(image.device) |
|
query_tokens = self.query_tokens.expand(image_embeds.shape[0], -1, -1) |
|
query_output = self.Qformer.bert( |
|
query_embeds=query_tokens, |
|
encoder_hidden_states=image_embeds, |
|
encoder_attention_mask=image_atts, |
|
return_dict=True, |
|
) |
|
|
|
query_output_down = self.encode_task_layer(query_output.last_hidden_state) |
|
quant, loss_embed, embed_ind = self.quantize(query_output_down) |
|
embed_ind = embed_ind.reshape(quant.shape[0], -1) |
|
|
|
query_output_up = self.decode_task_layer(quant) |
|
|
|
return embed_ind, query_output_up |
|
|
|
def get_codebook_entry(self, indices): |
|
with torch.no_grad(): |
|
quant_embedding = self.quantize.get_codebook_entry(indices) |
|
|
|
|
|
|
|
query_output_up = self.decode_task_layer(quant_embedding) |
|
|
|
pos_embed_image = self.pos_embed_image.repeat(query_output_up.shape[0], 1, 1) |
|
query_output_up_pos_image = query_output_up + pos_embed_image |
|
for blk in self.blocks_image: |
|
query_output_up_pos_image = blk(query_output_up_pos_image) |
|
query_output_up = query_output_up_pos_image |
|
|
|
reverse_output = self.image_down(query_output_up) |
|
reverse_output = reverse_output.reshape(reverse_output.shape[0], -1) |
|
reverse_output_proj = self.distill_image_proj(reverse_output) |
|
|
|
return reverse_output_proj |
|
|
|
@classmethod |
|
def get_vision_encoder(cls,model_name="eva_vit_g", |
|
img_size=224, |
|
drop_path_rate=0, |
|
use_grad_checkpoint=False, |
|
precision="fp32", |
|
cache_dir="./"): |
|
visual_encoder = create_eva_vit_g(img_size, drop_path_rate, use_grad_checkpoint, precision, cache_dir=cache_dir) |
|
visual_encoder.ln_vision = nn.LayerNorm(visual_encoder.num_features) |
|
for name, param in visual_encoder.named_parameters(): |
|
param.requires_grad = False |
|
visual_encoder = visual_encoder.eval() |
|
visual_encoder.ln_vision.weight.requires_grad = False |
|
visual_encoder.ln_vision.bias.requires_grad = False |
|
return visual_encoder |
|
|
|
class Seed2Tokenizer(PreTrainedModel): |
|
config_class = BertConfig |
|
base_model_prefix = "model" |
|
def __init__(self, |
|
config, |
|
image_size=224, |
|
drop_path_rate=0.4): |
|
super().__init__(config) |
|
|
|
model = Blip2QformerQuantizer(config) |
|
|
|
|
|
|
|
|
|
processor = transforms.Compose([ |
|
transforms.Resize((image_size, image_size), interpolation=3), |
|
|
|
|
|
transforms.ToTensor(), |
|
transforms.Normalize(mean=(0.48145466, 0.4578275, 0.40821073), std=(0.26862954, 0.26130258, 0.27577711)) |
|
]) |
|
|
|
shape_latents = torch.Size([1, 4, 96, 96]) |
|
self.register_buffer("latents",torch.randn(shape_latents, generator=None, layout=torch.strided)) |
|
|
|
|
|
|
|
self.model = model |
|
self.processor = processor |
|
self.visual_encoder = VisionTransformerEvaVit( |
|
img_size=image_size, |
|
patch_size=14, |
|
use_mean_pooling=False, |
|
embed_dim=1408, |
|
depth=39, |
|
num_heads=1408 // 88, |
|
mlp_ratio=4.3637, |
|
qkv_bias=True, |
|
drop_path_rate=drop_path_rate, |
|
norm_layer=partial(nn.LayerNorm, eps=1e-6), |
|
use_checkpoint=False, |
|
) |
|
|
|
|
|
def __len__(self): |
|
return self.model.n_embed |
|
|
|
def encode(self, image_torch, visual_encoder=None): |
|
'''Convert a batch of img to code |
|
Args: |
|
model: The tokenizer model. |
|
img: [b, c, h, w] |
|
''' |
|
if visual_encoder is None: |
|
visual_encoder = self.visual_encoder |
|
if len(image_torch.shape) == 3: |
|
image_torch = image_torch.unsqueeze(0) |
|
|
|
image_torch = image_torch.to(dtype=self.latents.dtype) |
|
image_torch = image_torch.to(self.device) |
|
|
|
img = image_torch |
|
|
|
|
|
|
|
with torch.no_grad(): |
|
id = self.model.get_codebook_indices_only(visual_encoder, img) |
|
return id.view(img.shape[0], -1) |
|
|
|
def decode(self, diffusion_model, indices, guidance_scale=10, noise_level=0, num_inference_steps=20,): |
|
image_embeds = self.model.get_codebook_entry(indices) |
|
image_embeds = image_embeds.to(dtype=diffusion_model.dtype, device=diffusion_model.device) |
|
image = diffusion_model( |
|
image_embeds=image_embeds, |
|
guidance_scale=guidance_scale, |
|
noise_level=noise_level, |
|
num_inference_steps=num_inference_steps, |
|
latents=self.latents.to(dtype=diffusion_model.dtype, device=diffusion_model.device), |
|
).images |
|
return image |
|
|
|
@property |
|
def num_image_tokens(self): |
|
return 8192 |
|
|
|
def encode_image( |
|
self, |
|
image_path=None, |
|
image_pil=None, |
|
image_torch=None, |
|
image_size: int = 224, |
|
visual_encoder = None, |
|
|
|
): |
|
assert (image_path is None) + (image_pil is None) + (image_torch is None) == 2 |
|
if visual_encoder is None: |
|
visual_encoder = self.visual_encoder |
|
|
|
if image_path is not None: |
|
image_pil = Image.open(image_path).convert('RGB') |
|
|
|
if image_pil is not None: |
|
image_torch = self.processor(image_pil) |
|
|
|
image_torch = image_torch.to(self.device) |
|
image_torch = image_torch.to(dtype=self.latents.dtype) |
|
return self.encode(image_torch, visual_encoder) |
|
|