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- # Copyright 2021 Google AI, Ross Wightman, The HuggingFace Inc. team. All rights reserved.
- #
- # Licensed under the Apache License, Version 2.0 (the "License");
- # you may not use this file except in compliance with the License.
- # You may obtain a copy of the License at
- #
- # http://www.apache.org/licenses/LICENSE-2.0
- #
- # Unless required by applicable law or agreed to in writing, software
- # distributed under the License is distributed on an "AS IS" BASIS,
- # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- # See the License for the specific language governing permissions and
- # limitations under the License.
- """PyTorch ViT model."""
- import collections.abc
- import math
- from collections.abc import Callable
- import torch
- from torch import nn
- from ... import initialization as init
- from ...activations import ACT2FN
- from ...modeling_layers import GradientCheckpointingLayer
- from ...modeling_outputs import (
- BaseModelOutput,
- BaseModelOutputWithPooling,
- ImageClassifierOutput,
- MaskedImageModelingOutput,
- )
- from ...modeling_utils import ALL_ATTENTION_FUNCTIONS, PreTrainedModel
- from ...processing_utils import Unpack
- from ...utils import TransformersKwargs, auto_docstring, logging, torch_int
- from ...utils.generic import can_return_tuple, merge_with_config_defaults
- from ...utils.output_capturing import capture_outputs
- from .configuration_vit import ViTConfig
- logger = logging.get_logger(__name__)
- class ViTEmbeddings(nn.Module):
- """
- Construct the CLS token, position and patch embeddings. Optionally, also the mask token.
- """
- def __init__(self, config: ViTConfig, use_mask_token: bool = False):
- super().__init__()
- self.cls_token = nn.Parameter(torch.randn(1, 1, config.hidden_size))
- self.mask_token = nn.Parameter(torch.zeros(1, 1, config.hidden_size)) if use_mask_token else None
- self.patch_embeddings = ViTPatchEmbeddings(config)
- num_patches = self.patch_embeddings.num_patches
- self.position_embeddings = nn.Parameter(torch.randn(1, num_patches + 1, config.hidden_size))
- self.dropout = nn.Dropout(config.hidden_dropout_prob)
- self.patch_size = config.patch_size
- self.config = config
- def interpolate_pos_encoding(self, embeddings: torch.Tensor, height: int, width: int) -> torch.Tensor:
- """
- This method allows to interpolate the pre-trained position encodings, to be able to use the model on higher resolution
- images. This method is also adapted to support torch.jit tracing.
- Adapted from:
- - https://github.com/facebookresearch/dino/blob/de9ee3df6cf39fac952ab558447af1fa1365362a/vision_transformer.py#L174-L194, and
- - https://github.com/facebookresearch/dinov2/blob/e1277af2ba9496fbadf7aec6eba56e8d882d1e35/dinov2/models/vision_transformer.py#L179-L211
- """
- num_patches = embeddings.shape[1] - 1
- num_positions = self.position_embeddings.shape[1] - 1
- # always interpolate when tracing to ensure the exported model works for dynamic input shapes
- if not torch.jit.is_tracing() and num_patches == num_positions and height == width:
- return self.position_embeddings
- class_pos_embed = self.position_embeddings[:, :1]
- patch_pos_embed = self.position_embeddings[:, 1:]
- dim = embeddings.shape[-1]
- new_height = height // self.patch_size
- new_width = width // self.patch_size
- sqrt_num_positions = torch_int(num_positions**0.5)
- patch_pos_embed = patch_pos_embed.reshape(1, sqrt_num_positions, sqrt_num_positions, dim)
- patch_pos_embed = patch_pos_embed.permute(0, 3, 1, 2)
- patch_pos_embed = nn.functional.interpolate(
- patch_pos_embed,
- size=(new_height, new_width),
- mode="bicubic",
- align_corners=False,
- )
- patch_pos_embed = patch_pos_embed.permute(0, 2, 3, 1).view(1, -1, dim)
- return torch.cat((class_pos_embed, patch_pos_embed), dim=1)
- def forward(
- self,
- pixel_values: torch.Tensor,
- bool_masked_pos: torch.BoolTensor | None = None,
- interpolate_pos_encoding: bool = False,
- ) -> torch.Tensor:
- batch_size, num_channels, height, width = pixel_values.shape
- embeddings = self.patch_embeddings(pixel_values, interpolate_pos_encoding=interpolate_pos_encoding)
- if bool_masked_pos is not None:
- seq_length = embeddings.shape[1]
- mask_tokens = self.mask_token.expand(batch_size, seq_length, -1)
- # replace the masked visual tokens by mask_tokens
- mask = bool_masked_pos.unsqueeze(-1).type_as(mask_tokens)
- embeddings = embeddings * (1.0 - mask) + mask_tokens * mask
- # add the [CLS] token to the embedded patch tokens
- cls_tokens = self.cls_token.expand(batch_size, -1, -1)
- embeddings = torch.cat((cls_tokens, embeddings), dim=1)
- # add positional encoding to each token
- if interpolate_pos_encoding:
- embeddings = embeddings + self.interpolate_pos_encoding(embeddings, height, width)
- else:
- embeddings = embeddings + self.position_embeddings
- embeddings = self.dropout(embeddings)
- return embeddings
- class ViTPatchEmbeddings(nn.Module):
- """
- This class turns `pixel_values` of shape `(batch_size, num_channels, height, width)` into the initial
- `hidden_states` (patch embeddings) of shape `(batch_size, seq_length, hidden_size)` to be consumed by a
- Transformer.
- """
- def __init__(self, config: ViTConfig):
- super().__init__()
- image_size, patch_size = config.image_size, config.patch_size
- num_channels, hidden_size = config.num_channels, config.hidden_size
- image_size = image_size if isinstance(image_size, collections.abc.Iterable) else (image_size, image_size)
- patch_size = patch_size if isinstance(patch_size, collections.abc.Iterable) else (patch_size, patch_size)
- num_patches = (image_size[1] // patch_size[1]) * (image_size[0] // patch_size[0])
- self.image_size = image_size
- self.patch_size = patch_size
- self.num_channels = num_channels
- self.num_patches = num_patches
- self.projection = nn.Conv2d(num_channels, hidden_size, kernel_size=patch_size, stride=patch_size)
- def forward(self, pixel_values: torch.Tensor, interpolate_pos_encoding: bool = False) -> torch.Tensor:
- batch_size, num_channels, height, width = pixel_values.shape
- if num_channels != self.num_channels:
- raise ValueError(
- "Make sure that the channel dimension of the pixel values match with the one set in the configuration."
- f" Expected {self.num_channels} but got {num_channels}."
- )
- if not interpolate_pos_encoding:
- if height != self.image_size[0] or width != self.image_size[1]:
- raise ValueError(
- f"Input image size ({height}*{width}) doesn't match model"
- f" ({self.image_size[0]}*{self.image_size[1]})."
- )
- embeddings = self.projection(pixel_values).flatten(2).transpose(1, 2)
- return embeddings
- # Copied from transformers.models.bert.modeling_bert.eager_attention_forward
- def eager_attention_forward(
- module: nn.Module,
- query: torch.Tensor,
- key: torch.Tensor,
- value: torch.Tensor,
- attention_mask: torch.Tensor | None,
- scaling: float | None = None,
- dropout: float = 0.0,
- **kwargs: Unpack[TransformersKwargs],
- ):
- if scaling is None:
- scaling = query.size(-1) ** -0.5
- # Take the dot product between "query" and "key" to get the raw attention scores.
- attn_weights = torch.matmul(query, key.transpose(2, 3)) * scaling
- if attention_mask is not None:
- attn_weights = attn_weights + attention_mask
- attn_weights = nn.functional.softmax(attn_weights, dim=-1)
- attn_weights = nn.functional.dropout(attn_weights, p=dropout, training=module.training)
- attn_output = torch.matmul(attn_weights, value)
- attn_output = attn_output.transpose(1, 2).contiguous()
- return attn_output, attn_weights
- class ViTSelfAttention(nn.Module):
- def __init__(self, config: ViTConfig):
- super().__init__()
- if config.hidden_size % config.num_attention_heads != 0 and not hasattr(config, "embedding_size"):
- raise ValueError(
- f"The hidden size {config.hidden_size} is not a multiple of the number of attention "
- f"heads {config.num_attention_heads}."
- )
- self.config = config
- 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.dropout_prob = config.attention_probs_dropout_prob
- self.scaling = self.attention_head_size**-0.5
- self.is_causal = False
- self.query = nn.Linear(config.hidden_size, self.all_head_size, bias=config.qkv_bias)
- self.key = nn.Linear(config.hidden_size, self.all_head_size, bias=config.qkv_bias)
- self.value = nn.Linear(config.hidden_size, self.all_head_size, bias=config.qkv_bias)
- def forward(
- self,
- hidden_states: torch.Tensor,
- **kwargs: Unpack[TransformersKwargs],
- ) -> tuple[torch.Tensor, torch.Tensor]:
- batch_size = hidden_states.shape[0]
- new_shape = batch_size, -1, self.num_attention_heads, self.attention_head_size
- key_layer = self.key(hidden_states).view(*new_shape).transpose(1, 2)
- value_layer = self.value(hidden_states).view(*new_shape).transpose(1, 2)
- query_layer = self.query(hidden_states).view(*new_shape).transpose(1, 2)
- attention_interface: Callable = ALL_ATTENTION_FUNCTIONS.get_interface(
- self.config._attn_implementation, eager_attention_forward
- )
- context_layer, attention_probs = attention_interface(
- self,
- query_layer,
- key_layer,
- value_layer,
- None,
- is_causal=self.is_causal,
- scaling=self.scaling,
- dropout=0.0 if not self.training else self.dropout_prob,
- **kwargs,
- )
- new_context_layer_shape = context_layer.size()[:-2] + (self.all_head_size,)
- context_layer = context_layer.reshape(new_context_layer_shape)
- return context_layer, attention_probs
- class ViTSelfOutput(nn.Module):
- """
- The residual connection is defined in ViTLayer instead of here (as is the case with other models), due to the
- layernorm applied before each block.
- """
- def __init__(self, config: ViTConfig):
- super().__init__()
- self.dense = nn.Linear(config.hidden_size, config.hidden_size)
- self.dropout = nn.Dropout(config.hidden_dropout_prob)
- def forward(self, hidden_states: torch.Tensor, input_tensor: torch.Tensor) -> torch.Tensor:
- hidden_states = self.dense(hidden_states)
- hidden_states = self.dropout(hidden_states)
- return hidden_states
- class ViTAttention(nn.Module):
- def __init__(self, config: ViTConfig):
- super().__init__()
- self.attention = ViTSelfAttention(config)
- self.output = ViTSelfOutput(config)
- def forward(
- self,
- hidden_states: torch.Tensor,
- **kwargs: Unpack[TransformersKwargs],
- ) -> torch.Tensor:
- self_attn_output, _ = self.attention(hidden_states, **kwargs)
- output = self.output(self_attn_output, hidden_states)
- return output
- class ViTIntermediate(nn.Module):
- def __init__(self, config: ViTConfig):
- 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: torch.Tensor) -> torch.Tensor:
- hidden_states = self.dense(hidden_states)
- hidden_states = self.intermediate_act_fn(hidden_states)
- return hidden_states
- class ViTOutput(nn.Module):
- def __init__(self, config: ViTConfig):
- super().__init__()
- self.dense = nn.Linear(config.intermediate_size, config.hidden_size)
- self.dropout = nn.Dropout(config.hidden_dropout_prob)
- def forward(self, hidden_states: torch.Tensor, input_tensor: torch.Tensor) -> torch.Tensor:
- hidden_states = self.dense(hidden_states)
- hidden_states = self.dropout(hidden_states)
- hidden_states = hidden_states + input_tensor
- return hidden_states
- class ViTLayer(GradientCheckpointingLayer):
- """This corresponds to the Block class in the timm implementation."""
- def __init__(self, config: ViTConfig):
- super().__init__()
- self.chunk_size_feed_forward = config.chunk_size_feed_forward
- self.seq_len_dim = 1
- self.attention = ViTAttention(config)
- self.intermediate = ViTIntermediate(config)
- self.output = ViTOutput(config)
- self.layernorm_before = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
- self.layernorm_after = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
- def forward(
- self,
- hidden_states: torch.Tensor,
- **kwargs: Unpack[TransformersKwargs],
- ) -> torch.Tensor:
- hidden_states_norm = self.layernorm_before(hidden_states)
- attention_output = self.attention(hidden_states_norm, **kwargs)
- # first residual connection
- hidden_states = attention_output + hidden_states
- # in ViT, layernorm is also applied after self-attention
- layer_output = self.layernorm_after(hidden_states)
- layer_output = self.intermediate(layer_output)
- # second residual connection is done here
- layer_output = self.output(layer_output, hidden_states)
- return layer_output
- class ViTEncoder(nn.Module):
- def __init__(self, config: ViTConfig):
- super().__init__()
- self.config = config
- self.layer = nn.ModuleList([ViTLayer(config) for _ in range(config.num_hidden_layers)])
- self.gradient_checkpointing = False
- def forward(
- self,
- hidden_states: torch.Tensor,
- **kwargs: Unpack[TransformersKwargs],
- ) -> BaseModelOutput:
- for layer_module in self.layer:
- hidden_states = layer_module(hidden_states, **kwargs)
- return BaseModelOutput(last_hidden_state=hidden_states)
- @auto_docstring
- class ViTPreTrainedModel(PreTrainedModel):
- config: ViTConfig
- base_model_prefix = "vit"
- main_input_name = "pixel_values"
- input_modalities = ("image",)
- supports_gradient_checkpointing = True
- _no_split_modules = ["ViTEmbeddings", "ViTLayer"]
- _supports_sdpa = True
- _supports_flash_attn = True
- _supports_flex_attn = True
- _supports_attention_backend = True
- _can_record_outputs = {
- "hidden_states": ViTLayer,
- "attentions": ViTSelfAttention,
- }
- @torch.no_grad()
- def _init_weights(self, module: nn.Linear | nn.Conv2d | nn.LayerNorm):
- """Initialize the weights"""
- if isinstance(module, nn.Linear | nn.Conv2d):
- init.trunc_normal_(module.weight, mean=0.0, std=self.config.initializer_range)
- if module.bias is not None:
- init.zeros_(module.bias)
- elif isinstance(module, nn.LayerNorm):
- init.zeros_(module.bias)
- init.ones_(module.weight)
- elif isinstance(module, ViTEmbeddings):
- init.trunc_normal_(module.position_embeddings, mean=0.0, std=self.config.initializer_range)
- init.trunc_normal_(module.cls_token, mean=0.0, std=self.config.initializer_range)
- if module.mask_token is not None:
- init.zeros_(module.mask_token)
- @auto_docstring
- class ViTModel(ViTPreTrainedModel):
- def __init__(self, config: ViTConfig, add_pooling_layer: bool = True, use_mask_token: bool = False):
- r"""
- add_pooling_layer (bool, *optional*, defaults to `True`):
- Whether to add a pooling layer
- use_mask_token (`bool`, *optional*, defaults to `False`):
- Whether to use a mask token for masked image modeling.
- """
- super().__init__(config)
- self.config = config
- self.embeddings = ViTEmbeddings(config, use_mask_token=use_mask_token)
- self.encoder = ViTEncoder(config)
- self.layernorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
- self.pooler = ViTPooler(config) if add_pooling_layer else None
- # Initialize weights and apply final processing
- self.post_init()
- def get_input_embeddings(self) -> ViTPatchEmbeddings:
- return self.embeddings.patch_embeddings
- @merge_with_config_defaults
- @capture_outputs(tie_last_hidden_states=False)
- @auto_docstring
- def forward(
- self,
- pixel_values: torch.Tensor | None = None,
- bool_masked_pos: torch.BoolTensor | None = None,
- interpolate_pos_encoding: bool | None = None,
- **kwargs: Unpack[TransformersKwargs],
- ) -> BaseModelOutputWithPooling:
- r"""
- bool_masked_pos (`torch.BoolTensor` of shape `(batch_size, num_patches)`, *optional*):
- Boolean masked positions. Indicates which patches are masked (1) and which aren't (0).
- """
- if pixel_values is None:
- raise ValueError("You have to specify pixel_values")
- # TODO: maybe have a cleaner way to cast the input (from `ImageProcessor` side?)
- expected_dtype = self.embeddings.patch_embeddings.projection.weight.dtype
- if pixel_values.dtype != expected_dtype:
- pixel_values = pixel_values.to(expected_dtype)
- embedding_output = self.embeddings(
- pixel_values, bool_masked_pos=bool_masked_pos, interpolate_pos_encoding=interpolate_pos_encoding
- )
- encoder_outputs: BaseModelOutput = self.encoder(embedding_output)
- sequence_output = encoder_outputs.last_hidden_state
- sequence_output = self.layernorm(sequence_output)
- pooled_output = self.pooler(sequence_output) if self.pooler is not None else None
- return BaseModelOutputWithPooling(last_hidden_state=sequence_output, pooler_output=pooled_output)
- class ViTPooler(nn.Module):
- def __init__(self, config: ViTConfig):
- super().__init__()
- self.dense = nn.Linear(config.hidden_size, config.pooler_output_size)
- self.activation = ACT2FN[config.pooler_act]
- def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
- # We "pool" the model by simply taking the hidden state corresponding
- # to the first token.
- first_token_tensor = hidden_states[:, 0]
- pooled_output = self.dense(first_token_tensor)
- pooled_output = self.activation(pooled_output)
- return pooled_output
- @auto_docstring(
- custom_intro="""
- ViT Model with a decoder on top for masked image modeling, as proposed in [SimMIM](https://huggingface.co/papers/2111.09886).
- <Tip>
- Note that we provide a script to pre-train this model on custom data in our [examples
- directory](https://github.com/huggingface/transformers/tree/main/examples/pytorch/image-pretraining).
- </Tip>
- """
- )
- class ViTForMaskedImageModeling(ViTPreTrainedModel):
- def __init__(self, config: ViTConfig):
- super().__init__(config)
- self.vit = ViTModel(config, add_pooling_layer=False, use_mask_token=True)
- self.decoder = nn.Sequential(
- nn.Conv2d(
- in_channels=config.hidden_size,
- out_channels=config.encoder_stride**2 * config.num_channels,
- kernel_size=1,
- ),
- nn.PixelShuffle(config.encoder_stride),
- )
- # Initialize weights and apply final processing
- self.post_init()
- @can_return_tuple
- @auto_docstring
- def forward(
- self,
- pixel_values: torch.Tensor | None = None,
- bool_masked_pos: torch.BoolTensor | None = None,
- interpolate_pos_encoding: bool | None = None,
- **kwargs: Unpack[TransformersKwargs],
- ) -> MaskedImageModelingOutput:
- r"""
- bool_masked_pos (`torch.BoolTensor` of shape `(batch_size, num_patches)`):
- Boolean masked positions. Indicates which patches are masked (1) and which aren't (0).
- Examples:
- ```python
- >>> from transformers import AutoImageProcessor, ViTForMaskedImageModeling
- >>> import torch
- >>> from PIL import Image
- >>> import httpx
- >>> from io import BytesIO
- >>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
- >>> with httpx.stream("GET", url) as response:
- ... image = Image.open(BytesIO(response.read()))
- >>> image_processor = AutoImageProcessor.from_pretrained("google/vit-base-patch16-224-in21k")
- >>> model = ViTForMaskedImageModeling.from_pretrained("google/vit-base-patch16-224-in21k")
- >>> num_patches = (model.config.image_size // model.config.patch_size) ** 2
- >>> pixel_values = image_processor(images=image, return_tensors="pt").pixel_values
- >>> # create random boolean mask of shape (batch_size, num_patches)
- >>> bool_masked_pos = torch.randint(low=0, high=2, size=(1, num_patches)).bool()
- >>> outputs = model(pixel_values, bool_masked_pos=bool_masked_pos)
- >>> loss, reconstructed_pixel_values = outputs.loss, outputs.reconstruction
- >>> list(reconstructed_pixel_values.shape)
- [1, 3, 224, 224]
- ```"""
- if bool_masked_pos is not None and (self.config.patch_size != self.config.encoder_stride):
- raise ValueError(
- "When `bool_masked_pos` is provided, `patch_size` must be equal to `encoder_stride` to ensure that "
- "the reconstructed image has the same dimensions as the input. "
- f"Got `patch_size` = {self.config.patch_size} and `encoder_stride` = {self.config.encoder_stride}."
- )
- outputs: BaseModelOutputWithPooling = self.vit(
- pixel_values,
- bool_masked_pos=bool_masked_pos,
- interpolate_pos_encoding=interpolate_pos_encoding,
- **kwargs,
- )
- sequence_output = outputs.last_hidden_state
- # Reshape to (batch_size, num_channels, height, width)
- sequence_output = sequence_output[:, 1:]
- batch_size, sequence_length, num_channels = sequence_output.shape
- height = width = math.floor(sequence_length**0.5)
- sequence_output = sequence_output.permute(0, 2, 1).reshape(batch_size, num_channels, height, width)
- # Reconstruct pixel values
- reconstructed_pixel_values = self.decoder(sequence_output)
- masked_im_loss = None
- if bool_masked_pos is not None:
- size = self.config.image_size // self.config.patch_size
- bool_masked_pos = bool_masked_pos.reshape(-1, size, size)
- mask = (
- bool_masked_pos.repeat_interleave(self.config.patch_size, 1)
- .repeat_interleave(self.config.patch_size, 2)
- .unsqueeze(1)
- .contiguous()
- )
- reconstruction_loss = nn.functional.l1_loss(pixel_values, reconstructed_pixel_values, reduction="none")
- masked_im_loss = (reconstruction_loss * mask).sum() / (mask.sum() + 1e-5) / self.config.num_channels
- return MaskedImageModelingOutput(
- loss=masked_im_loss,
- reconstruction=reconstructed_pixel_values,
- hidden_states=outputs.hidden_states,
- attentions=outputs.attentions,
- )
- @auto_docstring(
- custom_intro="""
- ViT Model transformer with an image classification head on top (a linear layer on top of the final hidden state of
- the [CLS] token) e.g. for ImageNet.
- <Tip>
- Note that it's possible to fine-tune ViT on higher resolution images than the ones it has been trained on, by
- setting `interpolate_pos_encoding` to `True` in the forward of the model. This will interpolate the pre-trained
- position embeddings to the higher resolution.
- </Tip>
- """
- )
- class ViTForImageClassification(ViTPreTrainedModel):
- def __init__(self, config: ViTConfig):
- super().__init__(config)
- self.num_labels = config.num_labels
- self.vit = ViTModel(config, add_pooling_layer=False)
- # Classifier head
- self.classifier = nn.Linear(config.hidden_size, config.num_labels) if config.num_labels > 0 else nn.Identity()
- # Initialize weights and apply final processing
- self.post_init()
- @can_return_tuple
- @auto_docstring
- def forward(
- self,
- pixel_values: torch.Tensor | None = None,
- labels: torch.Tensor | None = None,
- interpolate_pos_encoding: bool | None = None,
- **kwargs: Unpack[TransformersKwargs],
- ) -> ImageClassifierOutput:
- r"""
- labels (`torch.LongTensor` of shape `(batch_size,)`, *optional*):
- Labels for computing the image classification/regression loss. Indices should be in `[0, ...,
- config.num_labels - 1]`. If `config.num_labels == 1` a regression loss is computed (Mean-Square loss), If
- `config.num_labels > 1` a classification loss is computed (Cross-Entropy).
- """
- outputs: BaseModelOutputWithPooling = self.vit(
- pixel_values,
- interpolate_pos_encoding=interpolate_pos_encoding,
- **kwargs,
- )
- sequence_output = outputs.last_hidden_state
- pooled_output = sequence_output[:, 0, :]
- logits = self.classifier(pooled_output)
- loss = None
- if labels is not None:
- loss = self.loss_function(labels, logits, self.config, **kwargs)
- return ImageClassifierOutput(
- loss=loss,
- logits=logits,
- hidden_states=outputs.hidden_states,
- attentions=outputs.attentions,
- )
- __all__ = ["ViTForImageClassification", "ViTForMaskedImageModeling", "ViTModel", "ViTPreTrainedModel"]
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