team-10/venv/Lib/site-packages/transformers/models/siglip2/modeling_siglip2.py

1302 lines
53 KiB
Python
Raw Normal View History

2025-08-02 02:00:33 +02:00
# 🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨
# This file was automatically generated from src/transformers/models/siglip2/modular_siglip2.py.
# Do NOT edit this file manually as any edits will be overwritten by the generation of
# the file from the modular. If any change should be done, please apply the change to the
# modular_siglip2.py file directly. One of our CI enforces this.
# 🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨
# coding=utf-8
# Copyright 2025 The HuggingFace Inc. team.
#
# 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.
import math
import warnings
from dataclasses import dataclass
from typing import Any, Callable, Optional, Union
import numpy as np
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss
from torch.nn.init import _calculate_fan_in_and_fan_out
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 ...utils import ModelOutput, auto_docstring, can_return_tuple
from .configuration_siglip2 import Siglip2Config, Siglip2TextConfig, Siglip2VisionConfig
@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.
"""
)
class Siglip2VisionOutput(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: Optional[torch.FloatTensor] = None
last_hidden_state: Optional[torch.FloatTensor] = None
hidden_states: Optional[tuple[torch.FloatTensor, ...]] = None
attentions: Optional[tuple[torch.FloatTensor, ...]] = None
@dataclass
@auto_docstring(
custom_intro="""
Base class for text model's outputs that also contains a pooling of the last hidden states.
"""
)
class Siglip2TextOutput(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: Optional[torch.FloatTensor] = None
last_hidden_state: Optional[torch.FloatTensor] = None
hidden_states: Optional[tuple[torch.FloatTensor, ...]] = None
attentions: Optional[tuple[torch.FloatTensor, ...]] = None
@dataclass
@auto_docstring
class Siglip2Output(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 [`Siglip2TextModel`].
image_embeds (`torch.FloatTensor` of shape `(batch_size, output_dim`):
The image embeddings obtained by applying the projection layer to the pooled output of [`Siglip2VisionModel`].
text_model_output (`BaseModelOutputWithPooling`):
The output of the [`Siglip2TextModel`].
vision_model_output (`BaseModelOutputWithPooling`):
The output of the [`Siglip2VisionModel`].
"""
loss: Optional[torch.FloatTensor] = None
logits_per_image: Optional[torch.FloatTensor] = None
logits_per_text: Optional[torch.FloatTensor] = None
text_embeds: Optional[torch.FloatTensor] = None
image_embeds: Optional[torch.FloatTensor] = 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 Siglip2VisionEmbeddings(nn.Module):
def __init__(self, config: Siglip2VisionConfig):
super().__init__()
self.config = config
self.embed_dim = config.hidden_size
self.patch_size = config.patch_size
self.patch_embedding = nn.Linear(
in_features=config.num_channels * self.patch_size * self.patch_size,
out_features=self.embed_dim,
)
self.num_patches = config.num_patches
self.position_embedding_size = int(self.num_patches**0.5)
self.position_embedding = nn.Embedding(self.num_patches, self.embed_dim)
@staticmethod
def resize_positional_embeddings(
positional_embeddings: torch.Tensor,
spatial_shapes: torch.LongTensor,
max_length: int,
) -> torch.Tensor:
"""
Resize positional embeddings to image-specific size and pad to a fixed size.
Args:
positional_embeddings (`torch.Tensor`):
Position embeddings of shape (height, width, embed_dim)
spatial_shapes (`torch.LongTensor`):
Spatial shapes of shape (batch_size, 2) to resize the positional embeddings to
max_length (`int`):
Maximum length of the positional embeddings to pad resized positional embeddings to
Returns:
`torch.Tensor`: Embeddings of shape (batch_size, max_length, embed_dim)
"""
batch_size = spatial_shapes.shape[0]
embed_dim = positional_embeddings.shape[-1]
source_dtype = positional_embeddings.dtype
resulted_positional_embeddings = torch.empty(
(batch_size, max_length, embed_dim),
device=positional_embeddings.device,
dtype=source_dtype,
)
# (height, width, embed_dim) -> (1, embed_dim, height, width) for interpolation
positional_embeddings = positional_embeddings.permute(2, 0, 1).unsqueeze(0)
# Upcast to float32 on CPU because antialias is not supported for bfloat16/float16 on CPU
if positional_embeddings.device.type == "cpu":
positional_embeddings = positional_embeddings.to(torch.float32)
for i in range(batch_size):
# (1, dim, height, width) -> (1, dim, target_height, target_width)
height, width = spatial_shapes[i]
resized_embeddings = F.interpolate(
positional_embeddings,
size=(height, width),
mode="bilinear",
align_corners=False,
antialias=True,
)
# (1, dim, target_height, target_width) -> (target_height * target_width, dim)
resized_embeddings = resized_embeddings.reshape(embed_dim, height * width).transpose(0, 1)
# Cast to original dtype
resized_embeddings = resized_embeddings.to(source_dtype)
resulted_positional_embeddings[i, : height * width] = resized_embeddings
resulted_positional_embeddings[i, height * width :] = resized_embeddings[0]
return resulted_positional_embeddings
def forward(self, pixel_values: torch.FloatTensor, spatial_shapes: torch.LongTensor) -> torch.Tensor:
"""
Args:
pixel_values (`torch.FloatTensor`):
Pixel values of shape (batch_size, max_num_patches, num_channels * patch_size * patch_size)
spatial_shapes (`list[tuple[int, int]]`):
Spatial shapes of shape (batch_size, 2) to resize the positional embeddings to
"""
# Apply patch embeddings to already patchified pixel values
target_dtype = self.patch_embedding.weight.dtype
patch_embeds = self.patch_embedding(pixel_values.to(dtype=target_dtype))
# Get positional resized and padded positional embeddings
positional_embeddings = self.position_embedding.weight.reshape(
self.position_embedding_size, self.position_embedding_size, -1
)
resized_positional_embeddings = self.resize_positional_embeddings(
positional_embeddings, spatial_shapes, max_length=pixel_values.shape[1]
)
# Add positional embeddings to patch embeddings
embeddings = patch_embeds + resized_positional_embeddings
return embeddings
def eager_attention_forward(
module: nn.Module,
query: torch.Tensor,
key: torch.Tensor,
value: torch.Tensor,
attention_mask: Optional[torch.Tensor],
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 Siglip2Attention(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: Optional[torch.Tensor] = None,
**kwargs,
) -> tuple[torch.Tensor, Optional[torch.Tensor]]:
"""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 = eager_attention_forward
if self.config._attn_implementation != "eager":
attention_interface = ALL_ATTENTION_FUNCTIONS[self.config._attn_implementation]
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
class Siglip2MLP(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 Siglip2EncoderLayer(GradientCheckpointingLayer):
def __init__(self, config: Union[Siglip2VisionConfig, Siglip2TextConfig]):
super().__init__()
self.embed_dim = config.hidden_size
self.layer_norm1 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
self.self_attn = Siglip2Attention(config)
self.layer_norm2 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
self.mlp = Siglip2MLP(config)
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.Tensor,
output_attentions: Optional[bool] = False,
) -> tuple[torch.FloatTensor]:
"""
Args:
hidden_states (`torch.FloatTensor`):
Input to the layer of shape `(batch, seq_len, embed_dim)`.
attention_mask (`torch.FloatTensor`):
Attention mask of shape `(batch, 1, q_len, k_v_seq_len)` where padding elements are indicated by very large negative values.
output_attentions (`bool`, *optional*, defaults to `False`):
Whether or not to return the attentions tensors of all attention layers. See `attentions` under
returned tensors for more detail.
"""
residual = hidden_states
hidden_states = self.layer_norm1(hidden_states)
hidden_states, attn_weights = self.self_attn(
hidden_states=hidden_states,
attention_mask=attention_mask,
output_attentions=output_attentions,
)
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
outputs = (hidden_states,)
if output_attentions:
outputs += (attn_weights,)
return outputs
class Siglip2Encoder(nn.Module):
"""
Transformer encoder consisting of `config.num_hidden_layers` self attention layers. Each layer is a
[`Siglip2EncoderLayer`].
Args:
config: Siglip2Config
"""
def __init__(self, config: Siglip2Config):
super().__init__()
self.config = config
self.layers = nn.ModuleList([Siglip2EncoderLayer(config) for _ in range(config.num_hidden_layers)])
self.gradient_checkpointing = False
# Ignore copy
@can_return_tuple
def forward(
self,
inputs_embeds,
attention_mask: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
) -> BaseModelOutput:
r"""
Args:
inputs_embeds (`torch.FloatTensor` of shape `(batch_size, sequence_length, hidden_size)`):
Optionally, instead of passing `input_ids` you can choose to directly pass an embedded representation.
This is useful if you want more control over how to convert `input_ids` indices into associated vectors
than the model's internal embedding lookup matrix.
attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`:
- 1 for tokens that are **not masked**,
- 0 for tokens that are **masked**.
[What are attention masks?](../glossary#attention-mask)
output_attentions (`bool`, *optional*):
Whether or not to return the attentions tensors of all attention layers. See `attentions` under
returned tensors for more detail.
output_hidden_states (`bool`, *optional*):
Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors
for more detail.
return_dict (`bool`, *optional*):
Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
"""
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
)
encoder_states = () if output_hidden_states else None
all_attentions = () if output_attentions else None
hidden_states = inputs_embeds
for encoder_layer in self.layers:
if output_hidden_states:
encoder_states = encoder_states + (hidden_states,)
layer_outputs = encoder_layer(
hidden_states,
attention_mask,
output_attentions=output_attentions,
)
hidden_states = layer_outputs[0]
if output_attentions:
all_attentions = all_attentions + (layer_outputs[1],)
if output_hidden_states:
encoder_states = encoder_states + (hidden_states,)
return BaseModelOutput(
last_hidden_state=hidden_states,
hidden_states=encoder_states,
attentions=all_attentions,
)
class Siglip2VisionTransformer(nn.Module):
def __init__(self, config: Siglip2VisionConfig):
super().__init__()
self.config = config
embed_dim = config.hidden_size
self.embeddings = Siglip2VisionEmbeddings(config)
self.encoder = Siglip2Encoder(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 = Siglip2MultiheadAttentionPoolingHead(config)
self._use_flash_attention_2 = config._attn_implementation == "flash_attention_2"
@can_return_tuple
@auto_docstring
def forward(
self,
pixel_values: torch.FloatTensor,
attention_mask: torch.Tensor,
spatial_shapes: torch.LongTensor,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
) -> BaseModelOutputWithPooling:
r"""
spatial_shapes (`torch.LongTensor` of shape `(batch_size, 2)`):
Tensor containing the spatial dimensions (height, width) of the input images.
"""
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
)
hidden_states = self.embeddings(pixel_values, spatial_shapes)
if attention_mask is not None and not self._use_flash_attention_2:
# [batch_size, seq_len] -> [batch_size, 1, tgt_seq_len, src_seq_len]
encoder_attention_mask = _prepare_4d_attention_mask(attention_mask, hidden_states.dtype)
else:
encoder_attention_mask = attention_mask
encoder_outputs: BaseModelOutput = self.encoder(
inputs_embeds=hidden_states,
attention_mask=encoder_attention_mask,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
)
last_hidden_state = encoder_outputs.last_hidden_state
last_hidden_state = self.post_layernorm(last_hidden_state)
pooler_output = self.head(last_hidden_state, attention_mask) if self.use_head else None
return BaseModelOutputWithPooling(
last_hidden_state=last_hidden_state,
pooler_output=pooler_output,
hidden_states=encoder_outputs.hidden_states,
attentions=encoder_outputs.attentions,
)
class Siglip2TextEmbeddings(nn.Module):
def __init__(self, config: Siglip2TextConfig):
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: Optional[torch.LongTensor] = None,
position_ids: Optional[torch.LongTensor] = None,
inputs_embeds: Optional[torch.FloatTensor] = 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 _trunc_normal_(tensor, mean, std, a, b):
# Cut & paste from PyTorch official master until it's in a few official releases - RW
# Method based on https://people.sc.fsu.edu/~jburkardt/presentations/truncated_normal.pdf
def norm_cdf(x):
# Computes standard normal cumulative distribution function
return (1.0 + math.erf(x / math.sqrt(2.0))) / 2.0
if (mean < a - 2 * std) or (mean > b + 2 * std):
warnings.warn(
"mean is more than 2 std from [a, b] in nn.init.trunc_normal_. "
"The distribution of values may be incorrect.",
stacklevel=2,
)
# Values are generated by using a truncated uniform distribution and
# then using the inverse CDF for the normal distribution.
# Get upper and lower cdf values
l = norm_cdf((a - mean) / std)
u = norm_cdf((b - mean) / std)
# Uniformly fill tensor with values from [l, u], then translate to
# [2l-1, 2u-1].
tensor.uniform_(2 * l - 1, 2 * u - 1)
# Use inverse cdf transform for normal distribution to get truncated
# standard normal
tensor.erfinv_()
# Transform to proper mean, std
tensor.mul_(std * math.sqrt(2.0))
tensor.add_(mean)
# Clamp to ensure it's in the proper range
tensor.clamp_(min=a, max=b)
def trunc_normal_tf_(
tensor: torch.Tensor, mean: float = 0.0, std: float = 1.0, a: float = -2.0, b: float = 2.0
) -> torch.Tensor:
"""Fills the input Tensor with values drawn from a truncated
normal distribution. The values are effectively drawn from the
normal distribution :math:`\\mathcal{N}(\text{mean}, \text{std}^2)`
with values outside :math:`[a, b]` redrawn until they are within
the bounds. The method used for generating the random values works
best when :math:`a \\leq \text{mean} \\leq b`.
NOTE: this 'tf' variant behaves closer to Tensorflow / JAX impl where the
bounds [a, b] are applied when sampling the normal distribution with mean=0, std=1.0
and the result is subsequently scaled and shifted by the mean and std args.
Args:
tensor: an n-dimensional `torch.Tensor`
mean: the mean of the normal distribution
std: the standard deviation of the normal distribution
a: the minimum cutoff value
b: the maximum cutoff value
"""
with torch.no_grad():
_trunc_normal_(tensor, 0, 1.0, a, b)
tensor.mul_(std).add_(mean)
def variance_scaling_(tensor, scale=1.0, mode="fan_in", distribution="normal"):
fan_in, fan_out = _calculate_fan_in_and_fan_out(tensor)
if mode == "fan_in":
denom = fan_in
elif mode == "fan_out":
denom = fan_out
elif mode == "fan_avg":
denom = (fan_in + fan_out) / 2
variance = scale / denom
if distribution == "truncated_normal":
# constant is stddev of standard normal truncated to (-2, 2)
trunc_normal_tf_(tensor, std=math.sqrt(variance) / 0.87962566103423978)
elif distribution == "normal":
with torch.no_grad():
tensor.normal_(std=math.sqrt(variance))
elif distribution == "uniform":
bound = math.sqrt(3 * variance)
with torch.no_grad():
tensor.uniform_(-bound, bound)
else:
raise ValueError(f"invalid distribution {distribution}")
def lecun_normal_(tensor):
variance_scaling_(tensor, mode="fan_in", distribution="truncated_normal")
def default_flax_embed_init(tensor):
variance_scaling_(tensor, mode="fan_in", distribution="normal")
class Siglip2TextTransformer(nn.Module):
def __init__(self, config: Siglip2TextConfig):
super().__init__()
self.config = config
embed_dim = config.hidden_size
self.embeddings = Siglip2TextEmbeddings(config)
self.encoder = Siglip2Encoder(config)
self.final_layer_norm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)
self.head = nn.Linear(embed_dim, config.projection_size)
self._use_flash_attention_2 = config._attn_implementation == "flash_attention_2"
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: Optional[torch.Tensor] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
) -> BaseModelOutputWithPooling:
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
)
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: Siglip2's text model does not use a causal mask, unlike the original CLIP model.
# expand attention_mask
if attention_mask is not None and not self._use_flash_attention_2:
# [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,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
)
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,
hidden_states=encoder_outputs.hidden_states,
attentions=encoder_outputs.attentions,
)
@auto_docstring
class Siglip2PreTrainedModel(PreTrainedModel):
config: Siglip2Config
base_model_prefix = "siglip2"
supports_gradient_checkpointing = True
_no_split_modules = [
"Siglip2TextEmbeddings",
"Siglip2VisionEmbeddings",
"Siglip2EncoderLayer",
"Siglip2MultiheadAttentionPoolingHead",
]
_supports_flash_attn = True
_supports_sdpa = True
_supports_flex_attn = True
_supports_attention_backend = True
def _init_weights(self, module):
"""Initialize the weights"""
if isinstance(module, Siglip2VisionEmbeddings):
width = (
self.config.vision_config.hidden_size
if isinstance(self.config, Siglip2Config)
else self.config.hidden_size
)
nn.init.normal_(module.position_embedding.weight, std=1 / np.sqrt(width))
elif isinstance(module, nn.Embedding):
default_flax_embed_init(module.weight)
elif isinstance(module, Siglip2Attention):
nn.init.xavier_uniform_(module.q_proj.weight)
nn.init.xavier_uniform_(module.k_proj.weight)
nn.init.xavier_uniform_(module.v_proj.weight)
nn.init.xavier_uniform_(module.out_proj.weight)
nn.init.zeros_(module.q_proj.bias)
nn.init.zeros_(module.k_proj.bias)
nn.init.zeros_(module.v_proj.bias)
nn.init.zeros_(module.out_proj.bias)
elif isinstance(module, Siglip2MLP):
nn.init.xavier_uniform_(module.fc1.weight)
nn.init.xavier_uniform_(module.fc2.weight)
nn.init.normal_(module.fc1.bias, std=1e-6)
nn.init.normal_(module.fc2.bias, std=1e-6)
elif isinstance(module, Siglip2MultiheadAttentionPoolingHead):
nn.init.xavier_uniform_(module.probe.data)
nn.init.xavier_uniform_(module.attention.in_proj_weight.data)
nn.init.zeros_(module.attention.in_proj_bias.data)
elif isinstance(module, Siglip2Model):
logit_scale_init = torch.log(torch.tensor(1.0))
module.logit_scale.data.fill_(logit_scale_init)
module.logit_bias.data.zero_()
elif isinstance(module, Siglip2ForImageClassification):
nn.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)):
lecun_normal_(module.weight)
if module.bias is not None:
nn.init.zeros_(module.bias)
elif isinstance(module, nn.LayerNorm):
module.bias.data.zero_()
module.weight.data.fill_(1.0)
@auto_docstring(
custom_intro="""
The text model from Siglip2 without any head or projection on top.
"""
)
class Siglip2TextModel(Siglip2PreTrainedModel):
config: Siglip2TextConfig
def __init__(self, config: Siglip2TextConfig):
super().__init__(config)
self.text_model = Siglip2TextTransformer(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
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: Optional[torch.Tensor] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
) -> BaseModelOutputWithPooling:
r"""
Examples:
```python
>>> from transformers import AutoTokenizer, Siglip2TextModel
>>> model = Siglip2TextModel.from_pretrained("google/siglip2-base-patch16-224")
>>> tokenizer = AutoTokenizer.from_pretrained("google/siglip2-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,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
)
class Siglip2MultiheadAttentionPoolingHead(nn.Module):
"""Multihead Attention Pooling."""
def __init__(self, config: Siglip2VisionConfig):
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 = Siglip2MLP(config)
self.num_heads = config.num_attention_heads
def forward(self, hidden_state: torch.Tensor, attention_mask: Optional[torch.Tensor] = None) -> torch.Tensor:
batch_size = hidden_state.shape[0]
probe = self.probe.repeat(batch_size, 1, 1)
if attention_mask is not None:
target_len, source_len = probe.shape[1], hidden_state.shape[1]
attention_mask = _prepare_4d_attention_mask(attention_mask, hidden_state.dtype, target_len)
attention_mask = attention_mask.repeat(1, self.num_heads, target_len, 1)
attention_mask = attention_mask.reshape(-1, target_len, source_len)
hidden_state = self.attention(probe, hidden_state, hidden_state, attn_mask=attention_mask)[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 Siglip2 without any head or projection on top.
"""
)
class Siglip2VisionModel(Siglip2PreTrainedModel):
config: Siglip2VisionConfig
main_input_name = "pixel_values"
def __init__(self, config: Siglip2VisionConfig):
super().__init__(config)
self.vision_model = Siglip2VisionTransformer(config)
# Initialize weights and apply final processing
self.post_init()
def get_input_embeddings(self) -> nn.Module:
return self.vision_model.embeddings.patch_embedding
@can_return_tuple
@auto_docstring
def forward(
self,
pixel_values: torch.FloatTensor,
pixel_attention_mask: torch.Tensor,
spatial_shapes: torch.LongTensor,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
) -> BaseModelOutputWithPooling:
r"""
pixel_attention_mask (`torch.Tensor` of shape `(batch_size, image_size, image_size)`, *optional*):
Mask to avoid performing attention on padding pixel indices.
spatial_shapes (`torch.LongTensor` of shape `(batch_size, 2)`):
Tensor containing the spatial dimensions (height, width) of the input images.
Examples:
```python
>>> from PIL import Image
>>> import requests
>>> from transformers import AutoProcessor, Siglip2VisionModel
>>> model = Siglip2VisionModel.from_pretrained("google/siglip2-base-patch16-224")
>>> processor = AutoProcessor.from_pretrained("google/siglip2-base-patch16-224")
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> image = Image.open(requests.get(url, stream=True).raw)
>>> 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,
attention_mask=pixel_attention_mask,
spatial_shapes=spatial_shapes,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
)
@auto_docstring
class Siglip2Model(Siglip2PreTrainedModel):
config: Siglip2Config
def __init__(self, config: Siglip2Config):
super().__init__(config)
if not isinstance(config.text_config, Siglip2TextConfig):
raise TypeError(
"config.text_config is expected to be of type Siglip2TextConfig but is of type"
f" {type(config.text_config)}."
)
if not isinstance(config.vision_config, Siglip2VisionConfig):
raise TypeError(
"config.vision_config is expected to be of type Siglip2VisionConfig 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 = Siglip2TextModel._from_config(text_config)
vision_model = Siglip2VisionModel._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()
@auto_docstring
def get_text_features(
self,
input_ids: Optional[torch.Tensor] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
) -> torch.FloatTensor:
r"""
Returns:
text_features (`torch.FloatTensor` of shape `(batch_size, output_dim`): The text embeddings obtained by
applying the projection layer to the pooled output of [`Siglip2TextModel`].
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModel
>>> import torch
>>> model = AutoModel.from_pretrained("google/siglip2-base-patch16-224")
>>> tokenizer = AutoTokenizer.from_pretrained("google/siglip2-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)
```"""
# Use Siglip2 model's config for some fields (if specified) instead of those of vision & text components.
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
)
text_outputs: BaseModelOutputWithPooling = self.text_model(
input_ids=input_ids,
attention_mask=attention_mask,
position_ids=position_ids,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
)
pooled_output = text_outputs.pooler_output
return pooled_output
@auto_docstring
def get_image_features(
self,
pixel_values: Optional[torch.FloatTensor] = None,
pixel_attention_mask: Optional[torch.Tensor] = None,
spatial_shapes: Optional[torch.LongTensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
) -> torch.FloatTensor:
r"""
pixel_attention_mask (`torch.Tensor` of shape `(batch_size, image_size, image_size)`, *optional*):
Mask to avoid performing attention on padding pixel indices.
spatial_shapes (`torch.LongTensor` of shape `(batch_size, 2)`):
Tensor containing the spatial dimensions (height, width) of the input images.
Returns:
image_features (`torch.FloatTensor` of shape `(batch_size, output_dim`): The image embeddings obtained by
applying the projection layer to the pooled output of [`Siglip2VisionModel`].
Examples:
```python
>>> from PIL import Image
>>> import requests
>>> from transformers import AutoProcessor, AutoModel
>>> import torch
>>> model = AutoModel.from_pretrained("google/siglip2-base-patch16-224")
>>> processor = AutoProcessor.from_pretrained("google/siglip2-base-patch16-224")
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> image = Image.open(requests.get(url, stream=True).raw)
>>> inputs = processor(images=image, return_tensors="pt")
>>> with torch.no_grad():
... image_features = model.get_image_features(**inputs)
```
"""
# Use Siglip2Model's config for some fields (if specified) instead of those of vision & text components.
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
)
vision_outputs: BaseModelOutputWithPooling = self.vision_model(
pixel_values=pixel_values,
attention_mask=pixel_attention_mask,
spatial_shapes=spatial_shapes,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
)
pooled_output = vision_outputs.pooler_output
return pooled_output
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: Optional[torch.LongTensor] = None,
pixel_values: Optional[torch.FloatTensor] = None,
pixel_attention_mask: Optional[torch.Tensor] = None,
spatial_shapes: Optional[torch.LongTensor] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
return_loss: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
) -> Siglip2Output:
r"""
pixel_attention_mask (`torch.Tensor` of shape `(batch_size, image_size, image_size)`, *optional*):
Mask to avoid performing attention on padding pixel indices.
spatial_shapes (`torch.LongTensor` of shape `(batch_size, 2)`):
Tensor containing the spatial dimensions (height, width) of the input images.
return_loss (`bool`, *optional*):
Whether or not to return the contrastive loss.
Examples:
```python
>>> from PIL import Image
>>> import requests
>>> from transformers import AutoProcessor, AutoModel
>>> import torch
>>> model = AutoModel.from_pretrained("google/siglip2-base-patch16-224")
>>> processor = AutoProcessor.from_pretrained("google/siglip2-base-patch16-224")
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> image = Image.open(requests.get(url, stream=True).raw)
>>> 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'
```
"""
# Use Siglip2 model's config for some fields (if specified) instead of those of vision & text components.
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
)
vision_outputs: BaseModelOutputWithPooling = self.vision_model(
pixel_values=pixel_values,
attention_mask=pixel_attention_mask,
spatial_shapes=spatial_shapes,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
)
text_outputs: BaseModelOutputWithPooling = self.text_model(
input_ids=input_ids,
attention_mask=attention_mask,
position_ids=position_ids,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
)
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/siglip2.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 Siglip2Output(
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="""
Siglip2 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 Siglip2ForImageClassification(Siglip2PreTrainedModel):
main_input_name = "pixel_values"
def __init__(self, config: Siglip2Config) -> 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 = Siglip2VisionModel._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()
@can_return_tuple
@auto_docstring
def forward(
self,
pixel_values: Optional[torch.Tensor] = None,
pixel_attention_mask: Optional[torch.Tensor] = None,
spatial_shapes: Optional[torch.LongTensor] = None,
labels: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
) -> ImageClassifierOutput:
r"""
pixel_attention_mask (`torch.Tensor` of shape `(batch_size, image_size, image_size)`, *optional*):
Mask to avoid performing attention on padding pixel indices.
spatial_shapes (`torch.LongTensor` of shape `(batch_size, 2)`):
Tensor containing the spatial dimensions (height, width) of the input images.
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, Siglip2ForImageClassification
>>> import torch
>>> from PIL import Image
>>> import requests
>>> torch.manual_seed(3) # doctest: +IGNORE_RESULT
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> image = Image.open(requests.get(url, stream=True).raw)
>>> # note: we are loading a `Siglip2Model` 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/siglip2-base-patch16-224")
>>> model = Siglip2ForImageClassification.from_pretrained("google/siglip2-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
```
"""
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
)
outputs: BaseModelOutputWithPooling = self.vision_model(
pixel_values,
attention_mask=pixel_attention_mask,
spatial_shapes=spatial_shapes,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
)
sequence_output = outputs.last_hidden_state
# average pool the patch tokens
if pixel_attention_mask is not None:
pool_mask = pixel_attention_mask[..., None].to(sequence_output.device)
sequence_output = torch.sum(sequence_output * pool_mask, dim=1) / torch.sum(pool_mask, dim=1)
else:
sequence_output = torch.mean(sequence_output, dim=1)
# apply classifier
logits = self.classifier(sequence_output)
loss = None
if labels is not None:
# move labels to correct device to enable model parallelism
labels = labels.to(logits.device)
if self.config.problem_type is None:
if self.num_labels == 1:
self.config.problem_type = "regression"
elif self.num_labels > 1 and (labels.dtype == torch.long or labels.dtype == torch.int):
self.config.problem_type = "single_label_classification"
else:
self.config.problem_type = "multi_label_classification"
if self.config.problem_type == "regression":
loss_fct = MSELoss()
if self.num_labels == 1:
loss = loss_fct(logits.squeeze(), labels.squeeze())
else:
loss = loss_fct(logits, labels)
elif self.config.problem_type == "single_label_classification":
loss_fct = CrossEntropyLoss()
loss = loss_fct(logits.view(-1, self.num_labels), labels.view(-1))
elif self.config.problem_type == "multi_label_classification":
loss_fct = BCEWithLogitsLoss()
loss = loss_fct(logits, labels)
return ImageClassifierOutput(
loss=loss,
logits=logits,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
__all__ = [
"Siglip2Model",
"Siglip2PreTrainedModel",
"Siglip2TextModel",
"Siglip2VisionModel",
"Siglip2ForImageClassification",
]