You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

1019 lines
38 KiB

# Copyright 2024 Google AI and The HuggingFace 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 Siglip model."""
from collections.abc import Callable
from dataclasses import dataclass
from typing import Any
import numpy as np
import torch
from torch import nn
from ... import initialization as init
from ...activations import ACT2FN
from ...modeling_attn_mask_utils import _prepare_4d_attention_mask
from ...modeling_layers import GradientCheckpointingLayer
from ...modeling_outputs import BaseModelOutput, BaseModelOutputWithPooling, ImageClassifierOutput
from ...modeling_utils import ALL_ATTENTION_FUNCTIONS, PreTrainedModel
from ...processing_utils import Unpack
from ...utils import (
ModelOutput,
TransformersKwargs,
auto_docstring,
can_return_tuple,
torch_int,
)
from ...utils.generic import check_model_inputs, is_flash_attention_requested
from .configuration_siglip import SiglipConfig, SiglipTextConfig, SiglipVisionConfig
@dataclass
@auto_docstring(
custom_intro="""
Base class for vision model's outputs that also contains image embeddings of the pooling of the last hidden states.
"""
)
# Copied from transformers.models.clip.modeling_clip.CLIPVisionModelOutput with CLIP->Siglip
class SiglipVisionModelOutput(ModelOutput):
r"""
image_embeds (`torch.FloatTensor` of shape `(batch_size, output_dim)` *optional* returned when model is initialized with `with_projection=True`):
The image embeddings obtained by applying the projection layer to the pooler_output.
"""
image_embeds: torch.FloatTensor | None = None
last_hidden_state: torch.FloatTensor | None = None
hidden_states: tuple[torch.FloatTensor, ...] | None = None
attentions: tuple[torch.FloatTensor, ...] | None = None
@dataclass
@auto_docstring(
custom_intro="""
Base class for text model's outputs that also contains a pooling of the last hidden states.
"""
)
# Copied from transformers.models.clip.modeling_clip.CLIPTextModelOutput with CLIP->Siglip
class SiglipTextModelOutput(ModelOutput):
r"""
text_embeds (`torch.FloatTensor` of shape `(batch_size, output_dim)` *optional* returned when model is initialized with `with_projection=True`):
The text embeddings obtained by applying the projection layer to the pooler_output.
"""
text_embeds: torch.FloatTensor | None = None
last_hidden_state: torch.FloatTensor | None = None
hidden_states: tuple[torch.FloatTensor, ...] | None = None
attentions: tuple[torch.FloatTensor, ...] | None = None
@dataclass
@auto_docstring
# Copied from transformers.models.clip.modeling_clip.CLIPOutput with CLIP->Siglip
class SiglipOutput(ModelOutput):
r"""
loss (`torch.FloatTensor` of shape `(1,)`, *optional*, returned when `return_loss` is `True`):
Contrastive loss for image-text similarity.
logits_per_image (`torch.FloatTensor` of shape `(image_batch_size, text_batch_size)`):
The scaled dot product scores between `image_embeds` and `text_embeds`. This represents the image-text
similarity scores.
logits_per_text (`torch.FloatTensor` of shape `(text_batch_size, image_batch_size)`):
The scaled dot product scores between `text_embeds` and `image_embeds`. This represents the text-image
similarity scores.
text_embeds (`torch.FloatTensor` of shape `(batch_size, output_dim`):
The text embeddings obtained by applying the projection layer to the pooled output of [`SiglipTextModel`].
image_embeds (`torch.FloatTensor` of shape `(batch_size, output_dim`):
The image embeddings obtained by applying the projection layer to the pooled output of [`SiglipVisionModel`].
text_model_output (`BaseModelOutputWithPooling`):
The output of the [`SiglipTextModel`].
vision_model_output (`BaseModelOutputWithPooling`):
The output of the [`SiglipVisionModel`].
"""
loss: torch.FloatTensor | None = None
logits_per_image: torch.FloatTensor | None = None
logits_per_text: torch.FloatTensor | None = None
text_embeds: torch.FloatTensor | None = None
image_embeds: torch.FloatTensor | None = None
text_model_output: BaseModelOutputWithPooling = None
vision_model_output: BaseModelOutputWithPooling = None
def to_tuple(self) -> tuple[Any]:
return tuple(
self[k] if k not in ["text_model_output", "vision_model_output"] else getattr(self, k).to_tuple()
for k in self.keys()
)
class SiglipVisionEmbeddings(nn.Module):
def __init__(self, config: SiglipVisionConfig):
super().__init__()
self.config = config
self.embed_dim = config.hidden_size
self.image_size = config.image_size
self.patch_size = config.patch_size
self.patch_embedding = nn.Conv2d(
in_channels=config.num_channels,
out_channels=self.embed_dim,
kernel_size=self.patch_size,
stride=self.patch_size,
padding="valid",
)
self.num_patches = (self.image_size // self.patch_size) ** 2
self.num_positions = self.num_patches
self.position_embedding = nn.Embedding(self.num_positions, self.embed_dim)
self.register_buffer("position_ids", torch.arange(self.num_positions).expand((1, -1)), persistent=False)
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 and no class embeddings.
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]
num_positions = self.position_embedding.weight.shape[0]
# 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_embedding(self.position_ids)
patch_pos_embed = self.position_embedding.weight.unsqueeze(0)
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 patch_pos_embed
def forward(self, pixel_values: torch.FloatTensor, interpolate_pos_encoding=False) -> torch.Tensor:
_, _, height, width = pixel_values.shape
target_dtype = self.patch_embedding.weight.dtype
patch_embeds = self.patch_embedding(pixel_values.to(dtype=target_dtype)) # shape = [*, width, grid, grid]
embeddings = patch_embeds.flatten(2).transpose(1, 2)
if interpolate_pos_encoding:
embeddings = embeddings + self.interpolate_pos_encoding(embeddings, height, width)
else:
embeddings = embeddings + self.position_embedding(self.position_ids)
return embeddings
# Copied from transformers.models.clip.modeling_clip.CLIPTextEmbeddings with CLIP->Siglip
class SiglipTextEmbeddings(nn.Module):
def __init__(self, config: SiglipTextConfig):
super().__init__()
embed_dim = config.hidden_size
self.token_embedding = nn.Embedding(config.vocab_size, embed_dim)
self.position_embedding = nn.Embedding(config.max_position_embeddings, embed_dim)
# position_ids (1, len position emb) is contiguous in memory and exported when serialized
self.register_buffer(
"position_ids", torch.arange(config.max_position_embeddings).expand((1, -1)), persistent=False
)
def forward(
self,
input_ids: torch.LongTensor | None = None,
position_ids: torch.LongTensor | None = None,
inputs_embeds: torch.FloatTensor | None = None,
) -> torch.Tensor:
seq_length = input_ids.shape[-1] if input_ids is not None else inputs_embeds.shape[-2]
max_position_embedding = self.position_embedding.weight.shape[0]
if seq_length > max_position_embedding:
raise ValueError(
f"Sequence length must be less than max_position_embeddings (got `sequence length`: "
f"{seq_length} and max_position_embeddings: {max_position_embedding}"
)
if position_ids is None:
position_ids = self.position_ids[:, :seq_length]
if inputs_embeds is None:
inputs_embeds = self.token_embedding(input_ids)
position_embeddings = self.position_embedding(position_ids)
embeddings = inputs_embeds + position_embeddings
return embeddings
def eager_attention_forward(
module: nn.Module,
query: torch.Tensor,
key: torch.Tensor,
value: torch.Tensor,
attention_mask: torch.Tensor | None,
scaling: float,
dropout: float = 0.0,
**kwargs,
):
attn_weights = torch.matmul(query, key.transpose(-1, -2)) * scaling
if attention_mask is not None:
attn_weights = attn_weights + attention_mask
attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(query.dtype)
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 SiglipAttention(nn.Module):
"""Multi-headed attention from 'Attention Is All You Need' paper"""
def __init__(self, config):
super().__init__()
self.config = config
self.embed_dim = config.hidden_size
self.num_heads = config.num_attention_heads
self.head_dim = self.embed_dim // self.num_heads
if self.head_dim * self.num_heads != self.embed_dim:
raise ValueError(
f"embed_dim must be divisible by num_heads (got `embed_dim`: {self.embed_dim} and `num_heads`:"
f" {self.num_heads})."
)
self.scale = self.head_dim**-0.5
self.dropout = config.attention_dropout
self.is_causal = False
self.k_proj = nn.Linear(self.embed_dim, self.embed_dim)
self.v_proj = nn.Linear(self.embed_dim, self.embed_dim)
self.q_proj = nn.Linear(self.embed_dim, self.embed_dim)
self.out_proj = nn.Linear(self.embed_dim, self.embed_dim)
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.Tensor | None = None,
**kwargs,
) -> tuple[torch.Tensor, torch.Tensor | None]:
"""Input shape: Batch x Time x Channel"""
batch_size, seq_length, embed_dim = hidden_states.shape
queries = self.q_proj(hidden_states)
keys = self.k_proj(hidden_states)
values = self.v_proj(hidden_states)
queries = queries.view(batch_size, seq_length, self.num_heads, self.head_dim).transpose(1, 2)
keys = keys.view(batch_size, seq_length, self.num_heads, self.head_dim).transpose(1, 2)
values = values.view(batch_size, seq_length, self.num_heads, self.head_dim).transpose(1, 2)
attention_interface: Callable = ALL_ATTENTION_FUNCTIONS.get_interface(
self.config._attn_implementation, eager_attention_forward
)
attn_output, attn_weights = attention_interface(
self,
queries,
keys,
values,
attention_mask,
is_causal=self.is_causal,
scaling=self.scale,
dropout=0.0 if not self.training else self.dropout,
)
attn_output = attn_output.reshape(batch_size, seq_length, embed_dim).contiguous()
attn_output = self.out_proj(attn_output)
return attn_output, attn_weights
# Copied from transformers.models.clip.modeling_clip.CLIPMLP with CLIP->Siglip
class SiglipMLP(nn.Module):
def __init__(self, config):
super().__init__()
self.config = config
self.activation_fn = ACT2FN[config.hidden_act]
self.fc1 = nn.Linear(config.hidden_size, config.intermediate_size)
self.fc2 = nn.Linear(config.intermediate_size, config.hidden_size)
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
hidden_states = self.fc1(hidden_states)
hidden_states = self.activation_fn(hidden_states)
hidden_states = self.fc2(hidden_states)
return hidden_states
class SiglipEncoderLayer(GradientCheckpointingLayer):
def __init__(self, config: SiglipVisionConfig | SiglipTextConfig):
super().__init__()
self.embed_dim = config.hidden_size
self.layer_norm1 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
self.self_attn = SiglipAttention(config)
self.layer_norm2 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
self.mlp = SiglipMLP(config)
@auto_docstring
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.Tensor,
**kwargs: Unpack[TransformersKwargs],
) -> torch.FloatTensor:
residual = hidden_states
hidden_states = self.layer_norm1(hidden_states)
hidden_states, _ = self.self_attn(
hidden_states=hidden_states,
attention_mask=attention_mask,
**kwargs,
)
hidden_states = residual + hidden_states
residual = hidden_states
hidden_states = self.layer_norm2(hidden_states)
hidden_states = self.mlp(hidden_states)
hidden_states = residual + hidden_states
return hidden_states
@auto_docstring
class SiglipPreTrainedModel(PreTrainedModel):
config: SiglipConfig
base_model_prefix = "siglip"
input_modalities = ("image", "text")
supports_gradient_checkpointing = True
_no_split_modules = [
"SiglipTextEmbeddings",
"SiglipVisionEmbeddings",
"SiglipEncoderLayer",
"SiglipMultiheadAttentionPoolingHead",
]
_supports_flash_attn = True
_supports_sdpa = True
_supports_flex_attn = True
_supports_attention_backend = True
_can_record_outputs = {
"hidden_states": SiglipEncoderLayer,
"attentions": SiglipAttention,
}
@torch.no_grad()
def _init_weights(self, module):
"""Initialize the weights"""
if isinstance(module, SiglipVisionEmbeddings):
width = (
self.config.vision_config.hidden_size
if isinstance(self.config, SiglipConfig)
else self.config.hidden_size
)
init.normal_(module.position_embedding.weight, std=1 / np.sqrt(width))
if hasattr(module, "position_ids"):
init.copy_(module.position_ids, torch.arange(module.position_ids.shape[-1]).expand((1, -1)))
elif isinstance(module, nn.Embedding):
init.default_flax_embed_init_(module.weight)
elif isinstance(module, SiglipAttention):
init.xavier_uniform_(module.q_proj.weight)
init.xavier_uniform_(module.k_proj.weight)
init.xavier_uniform_(module.v_proj.weight)
init.xavier_uniform_(module.out_proj.weight)
init.zeros_(module.q_proj.bias)
init.zeros_(module.k_proj.bias)
init.zeros_(module.v_proj.bias)
init.zeros_(module.out_proj.bias)
elif isinstance(module, SiglipMLP):
init.xavier_uniform_(module.fc1.weight)
init.xavier_uniform_(module.fc2.weight)
init.normal_(module.fc1.bias, std=1e-6)
init.normal_(module.fc2.bias, std=1e-6)
elif isinstance(module, SiglipMultiheadAttentionPoolingHead):
init.xavier_uniform_(module.probe)
init.xavier_uniform_(module.attention.in_proj_weight)
init.zeros_(module.attention.in_proj_bias)
elif isinstance(module, SiglipModel):
init.zeros_(module.logit_scale)
init.zeros_(module.logit_bias)
elif isinstance(module, SiglipForImageClassification):
init.normal_(
module.classifier.weight,
std=self.config.vision_config.hidden_size**-0.5 * self.config.initializer_factor,
)
elif isinstance(module, (nn.Linear, nn.Conv2d)):
init.lecun_normal_(module.weight)
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, SiglipTextEmbeddings):
init.copy_(module.position_ids, torch.arange(module.position_ids.shape[-1]).expand((1, -1)))
# Copied from transformers.models.altclip.modeling_altclip.AltCLIPEncoder with AltCLIP->Siglip
class SiglipEncoder(nn.Module):
"""
Transformer encoder consisting of `config.num_hidden_layers` self attention layers. Each layer is a
[`SiglipEncoderLayer`].
Args:
config: SiglipConfig
"""
def __init__(self, config: SiglipConfig):
super().__init__()
self.config = config
self.layers = nn.ModuleList([SiglipEncoderLayer(config) for _ in range(config.num_hidden_layers)])
self.gradient_checkpointing = False
# Ignore copy
@auto_docstring
def forward(
self,
inputs_embeds,
attention_mask: torch.Tensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> BaseModelOutput:
hidden_states = inputs_embeds
for encoder_layer in self.layers:
hidden_states = encoder_layer(
hidden_states,
attention_mask,
**kwargs,
)
return BaseModelOutput(last_hidden_state=hidden_states)
class SiglipTextTransformer(SiglipPreTrainedModel):
_input_embed_layer = "token_embedding"
def __init__(self, config: SiglipTextConfig):
super().__init__(config)
self.config = config
embed_dim = config.hidden_size
self.embeddings = SiglipTextEmbeddings(config)
self.encoder = SiglipEncoder(config)
self.final_layer_norm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)
self.head = nn.Linear(embed_dim, config.projection_size)
self.post_init()
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: torch.Tensor | None = None,
attention_mask: torch.Tensor | None = None,
position_ids: torch.Tensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> BaseModelOutputWithPooling:
if input_ids is None:
raise ValueError("You have to specify input_ids")
input_shape = input_ids.size()
input_ids = input_ids.view(-1, input_shape[-1])
hidden_states = self.embeddings(input_ids=input_ids, position_ids=position_ids)
# note: SigLIP's text model does not use a causal mask, unlike the original CLIP model.
# expand attention_mask
uses_flash_attention = is_flash_attention_requested(self.config)
if uses_flash_attention:
attention_mask = None
elif attention_mask is not None and not uses_flash_attention:
# [batch_size, seq_len] -> [batch_size, 1, tgt_seq_len, src_seq_len]
attention_mask = _prepare_4d_attention_mask(attention_mask, hidden_states.dtype)
encoder_outputs: BaseModelOutput = self.encoder(
inputs_embeds=hidden_states,
attention_mask=attention_mask,
**kwargs,
)
last_hidden_state = encoder_outputs.last_hidden_state
last_hidden_state = self.final_layer_norm(last_hidden_state)
# The model uses the last token's hidden state, which may be padding.
pooled_output = last_hidden_state[:, -1, :]
pooled_output = self.head(pooled_output)
return BaseModelOutputWithPooling(
last_hidden_state=last_hidden_state,
pooler_output=pooled_output,
)
@auto_docstring(
custom_intro="""
The text model from SigLIP without any head or projection on top.
"""
)
class SiglipTextModel(SiglipPreTrainedModel):
config: SiglipTextConfig
input_modalities = ("text",)
def __init__(self, config: SiglipTextConfig):
super().__init__(config)
self.text_model = SiglipTextTransformer(config)
# Initialize weights and apply final processing
self.post_init()
def get_input_embeddings(self) -> nn.Module:
return self.text_model.embeddings.token_embedding
def set_input_embeddings(self, value):
self.text_model.embeddings.token_embedding = value
@check_model_inputs(tie_last_hidden_states=False)
@auto_docstring
def forward(
self,
input_ids: torch.Tensor | None = None,
attention_mask: torch.Tensor | None = None,
position_ids: torch.Tensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> BaseModelOutputWithPooling:
r"""
Examples:
```python
>>> from transformers import AutoTokenizer, SiglipTextModel
>>> model = SiglipTextModel.from_pretrained("google/siglip-base-patch16-224")
>>> tokenizer = AutoTokenizer.from_pretrained("google/siglip-base-patch16-224")
>>> # important: make sure to set padding="max_length" as that's how the model was trained
>>> inputs = tokenizer(["a photo of a cat", "a photo of a dog"], padding="max_length", return_tensors="pt")
>>> outputs = model(**inputs)
>>> last_hidden_state = outputs.last_hidden_state
>>> pooled_output = outputs.pooler_output # pooled (EOS token) states
```"""
return self.text_model(
input_ids=input_ids,
attention_mask=attention_mask,
position_ids=position_ids,
**kwargs,
)
class SiglipVisionTransformer(SiglipPreTrainedModel):
_input_embed_layer = "patch_embedding"
def __init__(self, config: SiglipVisionConfig):
super().__init__(config)
self.config = config
embed_dim = config.hidden_size
self.embeddings = SiglipVisionEmbeddings(config)
self.encoder = SiglipEncoder(config)
self.post_layernorm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)
self.use_head = True if not hasattr(config, "vision_use_head") else config.vision_use_head
if self.use_head:
self.head = SiglipMultiheadAttentionPoolingHead(config)
self.post_init()
@auto_docstring
def forward(
self,
pixel_values,
interpolate_pos_encoding: bool | None = False,
**kwargs: Unpack[TransformersKwargs],
) -> BaseModelOutputWithPooling:
hidden_states = self.embeddings(pixel_values, interpolate_pos_encoding=interpolate_pos_encoding)
encoder_outputs: BaseModelOutput = self.encoder(
inputs_embeds=hidden_states,
**kwargs,
)
last_hidden_state = encoder_outputs.last_hidden_state
last_hidden_state = self.post_layernorm(last_hidden_state)
pooler_output = self.head(last_hidden_state) if self.use_head else None
return BaseModelOutputWithPooling(
last_hidden_state=last_hidden_state,
pooler_output=pooler_output,
)
class SiglipMultiheadAttentionPoolingHead(nn.Module):
"""Multihead Attention Pooling."""
def __init__(self, config: SiglipVisionConfig):
super().__init__()
self.probe = nn.Parameter(torch.randn(1, 1, config.hidden_size))
self.attention = torch.nn.MultiheadAttention(config.hidden_size, config.num_attention_heads, batch_first=True)
self.layernorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.mlp = SiglipMLP(config)
def forward(self, hidden_state):
batch_size = hidden_state.shape[0]
probe = self.probe.repeat(batch_size, 1, 1)
hidden_state = self.attention(probe, hidden_state, hidden_state)[0]
residual = hidden_state
hidden_state = self.layernorm(hidden_state)
hidden_state = residual + self.mlp(hidden_state)
return hidden_state[:, 0]
@auto_docstring(
custom_intro="""
The vision model from SigLIP without any head or projection on top.
"""
)
class SiglipVisionModel(SiglipPreTrainedModel):
config: SiglipVisionConfig
main_input_name = "pixel_values"
input_modalities = ("image",)
def __init__(self, config: SiglipVisionConfig):
super().__init__(config)
self.vision_model = SiglipVisionTransformer(config)
# Initialize weights and apply final processing
self.post_init()
def get_input_embeddings(self) -> nn.Module:
return self.vision_model.embeddings.patch_embedding
@check_model_inputs(tie_last_hidden_states=False)
@auto_docstring
def forward(
self,
pixel_values,
interpolate_pos_encoding: bool = False,
**kwargs: Unpack[TransformersKwargs],
) -> BaseModelOutputWithPooling:
r"""
Examples:
```python
>>> from PIL import Image
>>> import httpx
>>> from io import BytesIO
>>> from transformers import AutoProcessor, SiglipVisionModel
>>> model = SiglipVisionModel.from_pretrained("google/siglip-base-patch16-224")
>>> processor = AutoProcessor.from_pretrained("google/siglip-base-patch16-224")
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> with httpx.stream("GET", url) as response:
... image = Image.open(BytesIO(response.read()))
>>> inputs = processor(images=image, return_tensors="pt")
>>> outputs = model(**inputs)
>>> last_hidden_state = outputs.last_hidden_state
>>> pooled_output = outputs.pooler_output # pooled features
```"""
return self.vision_model(
pixel_values=pixel_values,
interpolate_pos_encoding=interpolate_pos_encoding,
**kwargs,
)
@auto_docstring
class SiglipModel(SiglipPreTrainedModel):
config: SiglipConfig
def __init__(self, config: SiglipConfig):
super().__init__(config)
if not isinstance(config.text_config, SiglipTextConfig):
raise TypeError(
"config.text_config is expected to be of type SiglipTextConfig but is of type"
f" {type(config.text_config)}."
)
if not isinstance(config.vision_config, SiglipVisionConfig):
raise TypeError(
"config.vision_config is expected to be of type SiglipVisionConfig but is of type"
f" {type(config.vision_config)}."
)
text_config = config.text_config
vision_config = config.vision_config
# First, initialize the text and vision models with proper attention implementation
text_model = SiglipTextModel._from_config(text_config)
vision_model = SiglipVisionModel._from_config(vision_config)
# Second, get the text and vision submodules (for backward compatibility)
self.text_model = text_model.text_model
self.vision_model = vision_model.vision_model
self.logit_scale = nn.Parameter(torch.randn(1))
self.logit_bias = nn.Parameter(torch.randn(1))
# Initialize weights and apply final processing
self.post_init()
def get_input_embeddings(self) -> nn.Module:
return self.text_model.embeddings.token_embedding
def set_input_embeddings(self, value: nn.Module):
self.text_model.embeddings.token_embedding = value
@can_return_tuple
@auto_docstring
def get_text_features(
self,
input_ids: torch.Tensor,
attention_mask: torch.Tensor | None = None,
position_ids: torch.Tensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple | BaseModelOutputWithPooling:
r"""
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModel
>>> import torch
>>> model = AutoModel.from_pretrained("google/siglip-base-patch16-224")
>>> tokenizer = AutoTokenizer.from_pretrained("google/siglip-base-patch16-224")
>>> # important: make sure to set padding="max_length" as that's how the model was trained
>>> inputs = tokenizer(["a photo of a cat", "a photo of a dog"], padding="max_length", return_tensors="pt")
>>> with torch.no_grad():
... text_features = model.get_text_features(**inputs)
```"""
return self.text_model(
input_ids=input_ids,
attention_mask=attention_mask,
position_ids=position_ids,
**kwargs,
)
@can_return_tuple
@auto_docstring
def get_image_features(
self,
pixel_values: torch.FloatTensor,
interpolate_pos_encoding: bool = False,
**kwargs: Unpack[TransformersKwargs],
) -> tuple | BaseModelOutputWithPooling:
r"""
Examples:
```python
>>> import torch
>>> from transformers import AutoProcessor, AutoModel
>>> from transformers.image_utils import load_image
>>> model = AutoModel.from_pretrained("google/siglip-base-patch16-224")
>>> processor = AutoProcessor.from_pretrained("google/siglip-base-patch16-224")
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> image = load_image(url)
>>> inputs = processor(images=image, return_tensors="pt")
>>> with torch.no_grad():
... image_features = model.get_image_features(**inputs)
```"""
return self.vision_model(
pixel_values=pixel_values,
interpolate_pos_encoding=interpolate_pos_encoding,
**kwargs,
)
# NOTE: SiglipModel uses Pretrained backbones, so we don't need to add `check_model_inputs` here
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: torch.LongTensor | None = None,
pixel_values: torch.FloatTensor | None = None,
attention_mask: torch.Tensor | None = None,
position_ids: torch.LongTensor | None = None,
return_loss: bool | None = None,
interpolate_pos_encoding: bool = False,
**kwargs: Unpack[TransformersKwargs],
) -> SiglipOutput:
r"""
return_loss (`bool`, *optional*):
Whether or not to return the contrastive loss.
Examples:
```python
>>> from PIL import Image
>>> import httpx
>>> from io import BytesIO
>>> from transformers import AutoProcessor, AutoModel
>>> import torch
>>> model = AutoModel.from_pretrained("google/siglip-base-patch16-224")
>>> processor = AutoProcessor.from_pretrained("google/siglip-base-patch16-224")
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> with httpx.stream("GET", url) as response:
... image = Image.open(BytesIO(response.read()))
>>> texts = ["a photo of 2 cats", "a photo of 2 dogs"]
>>> # important: we pass `padding=max_length` since the model was trained with this
>>> inputs = processor(text=texts, images=image, padding="max_length", return_tensors="pt")
>>> with torch.no_grad():
... outputs = model(**inputs)
>>> logits_per_image = outputs.logits_per_image
>>> probs = torch.sigmoid(logits_per_image) # these are the probabilities
>>> print(f"{probs[0][0]:.1%} that image 0 is '{texts[0]}'")
31.9% that image 0 is 'a photo of 2 cats'
```"""
vision_outputs: BaseModelOutputWithPooling = self.vision_model(
pixel_values=pixel_values,
interpolate_pos_encoding=interpolate_pos_encoding,
**kwargs,
)
text_outputs: BaseModelOutputWithPooling = self.text_model(
input_ids=input_ids,
attention_mask=attention_mask,
position_ids=position_ids,
**kwargs,
)
image_embeds = vision_outputs.pooler_output
text_embeds = text_outputs.pooler_output
# normalized features
image_embeds = image_embeds / image_embeds.norm(p=2, dim=-1, keepdim=True)
text_embeds = text_embeds / text_embeds.norm(p=2, dim=-1, keepdim=True)
# cosine similarity as logits
logits_per_text = torch.matmul(text_embeds, image_embeds.t().to(text_embeds.device))
logit_scale, logit_bias = self.logit_scale.to(text_embeds.device), self.logit_bias.to(text_embeds.device)
logits_per_text = logits_per_text * logit_scale.exp() + logit_bias
logits_per_image = logits_per_text.t()
loss = None
if return_loss:
# Adapted from https://github.com/google-research/big_vision/blob/01edb81a4716f93a48be43b3a4af14e29cdb3a7f/big_vision/trainers/proj/image_text/siglip.py#L287
eye = torch.eye(logits_per_text.size(0), device=logits_per_text.device)
m1_diag1 = -torch.ones_like(logits_per_text) + 2 * eye
loglik = torch.nn.functional.logsigmoid(m1_diag1 * logits_per_text)
nll = -torch.sum(loglik, dim=-1)
loss = nll.mean()
return SiglipOutput(
loss=loss,
logits_per_image=logits_per_image,
logits_per_text=logits_per_text,
text_embeds=text_embeds,
image_embeds=image_embeds,
text_model_output=text_outputs,
vision_model_output=vision_outputs,
)
@auto_docstring(
custom_intro="""
SigLIP vision encoder with an image classification head on top (a linear layer on top of the pooled final hidden states of
the patch tokens) e.g. for ImageNet.
"""
)
class SiglipForImageClassification(SiglipPreTrainedModel):
main_input_name = "pixel_values"
input_modalities = ("image",)
def __init__(self, config: SiglipConfig) -> None:
super().__init__(config)
self.num_labels = config.num_labels
# Create the vision model with proper attention
# and take only vision_model submodule (for backward compatibility)
vision_model = SiglipVisionModel._from_config(config.vision_config)
self.vision_model = vision_model.vision_model
# Classifier head
self.classifier = (
nn.Linear(config.vision_config.hidden_size, config.num_labels) if config.num_labels > 0 else nn.Identity()
)
# Initialize weights and apply final processing
self.post_init()
def get_input_embeddings(self) -> nn.Module:
return self.vision_model.embeddings.patch_embedding
def set_input_embeddings(self, value: nn.Module):
self.vision_model.embeddings.patch_embedding = value
@check_model_inputs
@auto_docstring
def forward(
self,
pixel_values: torch.Tensor | None = None,
labels: torch.Tensor | None = None,
interpolate_pos_encoding: bool = False,
**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).
Examples:
```python
>>> from transformers import AutoImageProcessor, SiglipForImageClassification
>>> import torch
>>> from PIL import Image
>>> import httpx
>>> from io import BytesIO
>>> torch.manual_seed(3) # doctest: +IGNORE_RESULT
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> with httpx.stream("GET", url) as response:
... image = Image.open(BytesIO(response.read()))
>>> # note: we are loading a `SiglipModel` from the hub here,
>>> # so the head will be randomly initialized, hence the predictions will be random if seed is not set above.
>>> image_processor = AutoImageProcessor.from_pretrained("google/siglip-base-patch16-224")
>>> model = SiglipForImageClassification.from_pretrained("google/siglip-base-patch16-224")
>>> inputs = image_processor(images=image, return_tensors="pt")
>>> outputs = model(**inputs)
>>> logits = outputs.logits
>>> # model predicts one of the two classes
>>> predicted_class_idx = logits.argmax(-1).item()
>>> print("Predicted class:", model.config.id2label[predicted_class_idx])
Predicted class: LABEL_1
```"""
outputs: BaseModelOutputWithPooling = self.vision_model(
pixel_values,
interpolate_pos_encoding=interpolate_pos_encoding,
**kwargs,
)
sequence_output = outputs.last_hidden_state
# average pool the patch tokens
sequence_output = torch.mean(sequence_output, dim=1)
# apply classifier
logits = self.classifier(sequence_output)
loss = None
if labels is not None:
loss = self.loss_function(labels, logits, self.config)
return ImageClassifierOutput(
loss=loss,
logits=logits,
)
__all__ = [
"SiglipModel",
"SiglipPreTrainedModel",
"SiglipTextModel",
"SiglipVisionModel",
"SiglipForImageClassification",
]