team-10/venv/Lib/site-packages/transformers/models/git/modeling_git.py
2025-08-02 02:00:33 +02:00

1460 lines
61 KiB
Python

# coding=utf-8
# Copyright 2022 Microsoft Research and 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 GIT model."""
import math
from dataclasses import dataclass
from typing import Callable, Optional, Union
import torch
import torch.utils.checkpoint
from torch import nn
from ...activations import ACT2FN
from ...cache_utils import Cache, DynamicCache
from ...generation import GenerationMixin
from ...modeling_attn_mask_utils import _prepare_4d_attention_mask
from ...modeling_layers import GradientCheckpointingLayer
from ...modeling_outputs import (
BaseModelOutput,
BaseModelOutputWithPast,
BaseModelOutputWithPooling,
CausalLMOutputWithPast,
)
from ...modeling_utils import ALL_ATTENTION_FUNCTIONS, PreTrainedModel
from ...pytorch_utils import apply_chunking_to_forward, find_pruneable_heads_and_indices, prune_linear_layer
from ...utils import (
ModelOutput,
auto_docstring,
can_return_tuple,
logging,
torch_int,
)
from .configuration_git import GitConfig, GitVisionConfig
logger = logging.get_logger(__name__)
@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->Git
class GitVisionModelOutput(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
class GitEmbeddings(nn.Module):
"""Construct the embeddings from word and position embeddings."""
def __init__(self, config):
super().__init__()
self.word_embeddings = nn.Embedding(config.vocab_size, config.hidden_size, padding_idx=config.pad_token_id)
self.position_embeddings = nn.Embedding(config.max_position_embeddings, config.hidden_size)
# self.LayerNorm is not snake-cased to stick with TensorFlow model variable name and be able to load
# any TensorFlow checkpoint file
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.dropout = nn.Dropout(config.hidden_dropout_prob)
# position_ids (1, len position emb) is contiguous in memory and exported when serialized
self.position_embedding_type = getattr(config, "position_embedding_type", "absolute")
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,
past_key_values_length: int = 0,
) -> torch.Tensor:
if input_ids is not None:
input_shape = input_ids.size()
else:
input_shape = inputs_embeds.size()[:-1]
seq_length = input_shape[1]
if position_ids is None:
position_ids = self.position_ids[:, past_key_values_length : seq_length + past_key_values_length]
if inputs_embeds is None:
embeddings = self.word_embeddings(input_ids)
else:
embeddings = inputs_embeds
if self.position_embedding_type == "absolute":
position_embeddings = self.position_embeddings(position_ids)
embeddings += position_embeddings
embeddings = self.LayerNorm(embeddings)
embeddings = self.dropout(embeddings)
return embeddings
class GitSelfAttention(nn.Module):
def __init__(self, config, position_embedding_type=None, layer_idx=None):
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.layer_idx = layer_idx
if layer_idx is None:
logger.warning_once(
f"Instantiating {self.__class__.__name__} without passing a `layer_idx` is not recommended and will "
"lead to errors during the forward call if caching is used. Please make sure to provide a `layer_idx` "
"when creating this class."
)
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.image_patch_tokens = int((config.vision_config.image_size / config.vision_config.patch_size) ** 2 + 1)
if config.num_image_with_embedding is not None:
self.image_patch_tokens *= config.num_image_with_embedding
self.query = nn.Linear(config.hidden_size, self.all_head_size)
self.key = nn.Linear(config.hidden_size, self.all_head_size)
self.value = nn.Linear(config.hidden_size, self.all_head_size)
self.dropout = nn.Dropout(config.attention_probs_dropout_prob)
self.position_embedding_type = position_embedding_type or getattr(
config, "position_embedding_type", "absolute"
)
if self.position_embedding_type == "relative_key" or self.position_embedding_type == "relative_key_query":
self.max_position_embeddings = config.max_position_embeddings
self.distance_embedding = nn.Embedding(2 * config.max_position_embeddings - 1, self.attention_head_size)
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: Optional[torch.FloatTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
past_key_value: Optional[Cache] = None,
output_attentions: Optional[bool] = False,
pixel_values_present: Optional[bool] = False,
) -> tuple[torch.Tensor]:
batch_size, seq_length, _ = hidden_states.shape
query_layer = (
self.query(hidden_states)
.view(batch_size, -1, self.num_attention_heads, self.attention_head_size)
.transpose(1, 2)
)
cutoff = self.image_patch_tokens if pixel_values_present else 0
key_layer = (
self.key(hidden_states)
.view(batch_size, -1, self.num_attention_heads, self.attention_head_size)
.transpose(1, 2)
)
value_layer = (
self.value(hidden_states)
.view(batch_size, -1, self.num_attention_heads, self.attention_head_size)
.transpose(1, 2)
)
if past_key_value is not None:
# NOTE: like in other caches, we store the text component. In GIT it means we discard the image component.
key_layer_past, value_layer_past = past_key_value.update(
key_layer[:, :, cutoff:, :], value_layer[:, :, cutoff:, :], self.layer_idx
)
key_layer = torch.cat([key_layer[:, :, :cutoff, :], key_layer_past], dim=2)
value_layer = torch.cat([value_layer[:, :, :cutoff, :], value_layer_past], dim=2)
# Take the dot product between "query" and "key" to get the raw attention scores.
attention_scores = torch.matmul(query_layer, key_layer.transpose(-1, -2))
if self.position_embedding_type == "relative_key" or self.position_embedding_type == "relative_key_query":
query_length, key_length = query_layer.shape[2], key_layer.shape[2]
if past_key_value is not None:
position_ids_l = torch.tensor(key_length - 1, dtype=torch.long, device=hidden_states.device).view(
-1, 1
)
else:
position_ids_l = torch.arange(query_length, dtype=torch.long, device=hidden_states.device).view(-1, 1)
position_ids_r = torch.arange(key_length, dtype=torch.long, device=hidden_states.device).view(1, -1)
distance = position_ids_l - position_ids_r
positional_embedding = self.distance_embedding(distance + self.max_position_embeddings - 1)
positional_embedding = positional_embedding.to(dtype=query_layer.dtype) # fp16 compatibility
if self.position_embedding_type == "relative_key":
relative_position_scores = torch.einsum("bhld,lrd->bhlr", query_layer, positional_embedding)
attention_scores = attention_scores + relative_position_scores
elif self.position_embedding_type == "relative_key_query":
relative_position_scores_query = torch.einsum("bhld,lrd->bhlr", query_layer, positional_embedding)
relative_position_scores_key = torch.einsum("bhrd,lrd->bhlr", key_layer, positional_embedding)
attention_scores = attention_scores + relative_position_scores_query + relative_position_scores_key
attention_scores = attention_scores / math.sqrt(self.attention_head_size)
if attention_mask is not None:
# Apply the attention mask is (precomputed for all layers in GitModel forward() function)
attention_scores = attention_scores + attention_mask
# Normalize the attention scores to probabilities.
attention_probs = nn.functional.softmax(attention_scores, dim=-1)
# This is actually dropping out entire tokens to attend to, which might
# seem a bit unusual, but is taken from the original Transformer paper.
attention_probs = self.dropout(attention_probs)
# Mask heads if we want to
if head_mask is not None:
attention_probs = attention_probs * head_mask
context_layer = torch.matmul(attention_probs, value_layer)
context_layer = context_layer.permute(0, 2, 1, 3).contiguous()
new_context_layer_shape = context_layer.size()[:-2] + (self.all_head_size,)
context_layer = context_layer.view(new_context_layer_shape)
return context_layer, attention_probs
# Copied from transformers.models.bert.modeling_bert.BertSelfOutput
class GitSelfOutput(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = nn.Linear(config.hidden_size, config.hidden_size)
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.dropout = nn.Dropout(config.hidden_dropout_prob)
def forward(self, hidden_states: torch.Tensor, input_tensor: torch.Tensor) -> torch.Tensor:
hidden_states = self.dense(hidden_states)
hidden_states = self.dropout(hidden_states)
hidden_states = self.LayerNorm(hidden_states + input_tensor)
return hidden_states
GIT_SELF_ATTENTION_CLASSES = {
"eager": GitSelfAttention,
}
class GitAttention(nn.Module):
def __init__(self, config, position_embedding_type=None, layer_idx=None):
super().__init__()
self.self = GIT_SELF_ATTENTION_CLASSES[config._attn_implementation](
config, position_embedding_type=position_embedding_type, layer_idx=layer_idx
)
self.output = GitSelfOutput(config)
self.pruned_heads = set()
# Copied from transformers.models.bert.modeling_bert.BertAttention.prune_heads
def prune_heads(self, heads):
if len(heads) == 0:
return
heads, index = find_pruneable_heads_and_indices(
heads, self.self.num_attention_heads, self.self.attention_head_size, self.pruned_heads
)
# Prune linear layers
self.self.query = prune_linear_layer(self.self.query, index)
self.self.key = prune_linear_layer(self.self.key, index)
self.self.value = prune_linear_layer(self.self.value, index)
self.output.dense = prune_linear_layer(self.output.dense, index, dim=1)
# Update hyper params and store pruned heads
self.self.num_attention_heads = self.self.num_attention_heads - len(heads)
self.self.all_head_size = self.self.attention_head_size * self.self.num_attention_heads
self.pruned_heads = self.pruned_heads.union(heads)
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: Optional[torch.FloatTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
past_key_value: Optional[Cache] = None,
output_attentions: Optional[bool] = False,
pixel_values_present: Optional[bool] = False,
) -> tuple[torch.Tensor]:
attn_output, self_attn_weights = self.self(
hidden_states,
attention_mask,
head_mask,
past_key_value,
output_attentions,
pixel_values_present,
)
attention_output = self.output(attn_output, hidden_states)
return attention_output, self_attn_weights
# Copied from transformers.models.bert.modeling_bert.BertIntermediate
class GitIntermediate(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = nn.Linear(config.hidden_size, config.intermediate_size)
if isinstance(config.hidden_act, str):
self.intermediate_act_fn = ACT2FN[config.hidden_act]
else:
self.intermediate_act_fn = config.hidden_act
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
hidden_states = self.dense(hidden_states)
hidden_states = self.intermediate_act_fn(hidden_states)
return hidden_states
# Copied from transformers.models.bert.modeling_bert.BertOutput
class GitOutput(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = nn.Linear(config.intermediate_size, config.hidden_size)
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.dropout = nn.Dropout(config.hidden_dropout_prob)
def forward(self, hidden_states: torch.Tensor, input_tensor: torch.Tensor) -> torch.Tensor:
hidden_states = self.dense(hidden_states)
hidden_states = self.dropout(hidden_states)
hidden_states = self.LayerNorm(hidden_states + input_tensor)
return hidden_states
class GitLayer(GradientCheckpointingLayer):
def __init__(self, config, layer_idx=None):
super().__init__()
self.chunk_size_feed_forward = config.chunk_size_feed_forward
self.seq_len_dim = 1
self.attention = GitAttention(config, layer_idx=layer_idx)
self.intermediate = GitIntermediate(config)
self.output = GitOutput(config)
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: Optional[torch.FloatTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
past_key_value: Optional[Cache] = None,
output_attentions: Optional[bool] = False,
pixel_values_present: Optional[bool] = False,
) -> tuple[torch.Tensor]:
# decoder uni-directional self-attention cached key/values tuple is at positions 1,2
attention_output, self_attention_weights = self.attention(
hidden_states,
attention_mask,
head_mask,
output_attentions=output_attentions,
past_key_value=past_key_value,
pixel_values_present=pixel_values_present,
)
layer_output = apply_chunking_to_forward(
self.feed_forward_chunk, self.chunk_size_feed_forward, self.seq_len_dim, attention_output
)
return layer_output, self_attention_weights
def feed_forward_chunk(self, attention_output):
intermediate_output = self.intermediate(attention_output)
layer_output = self.output(intermediate_output, attention_output)
return layer_output
class GitEncoder(nn.Module):
def __init__(self, config):
super().__init__()
self.config = config
self.layer = nn.ModuleList([GitLayer(config, i) for i in range(config.num_hidden_layers)])
self.gradient_checkpointing = False
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: Optional[torch.FloatTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
past_key_values: Optional[Union[Cache, tuple[tuple[torch.FloatTensor]]]] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = False,
output_hidden_states: Optional[bool] = False,
pixel_values_present: Optional[bool] = False,
return_dict: Optional[bool] = True,
) -> Union[tuple[torch.Tensor], BaseModelOutputWithPast]:
if self.gradient_checkpointing and self.training:
if use_cache:
logger.warning_once(
"`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`..."
)
use_cache = False
# TODO (joao): remove this exception in v4.56 -- it exists for users that try to pass a legacy cache
if not isinstance(past_key_values, (type(None), Cache)):
raise ValueError("The `past_key_values` should be either a `Cache` object or `None`.")
if use_cache and past_key_values is None:
past_key_values = DynamicCache()
all_hidden_states = () if output_hidden_states else None
all_self_attentions = () if output_attentions else None
for i, layer_module in enumerate(self.layer):
if output_hidden_states:
all_hidden_states = all_hidden_states + (hidden_states,)
layer_head_mask = head_mask[i] if head_mask is not None else None
layer_outputs = layer_module(
hidden_states,
attention_mask,
layer_head_mask,
past_key_values,
output_attentions,
pixel_values_present,
)
hidden_states = layer_outputs[0]
if output_attentions:
all_self_attentions = all_self_attentions + (layer_outputs[1],)
if output_hidden_states:
all_hidden_states = all_hidden_states + (hidden_states,)
if not return_dict:
return tuple(
v
for v in [
hidden_states,
past_key_values,
all_hidden_states,
all_self_attentions,
]
if v is not None
)
return BaseModelOutputWithPast(
last_hidden_state=hidden_states,
past_key_values=past_key_values,
hidden_states=all_hidden_states,
attentions=all_self_attentions,
)
@auto_docstring
class GitPreTrainedModel(PreTrainedModel):
config: GitConfig
base_model_prefix = "git"
supports_gradient_checkpointing = True
def _init_weights(self, module):
"""Initialize the weights"""
if isinstance(module, GitVisionEmbeddings):
nn.init.normal_(module.class_embedding, mean=0.0, std=self.config.initializer_range)
nn.init.normal_(module.patch_embedding.weight, std=self.config.initializer_range)
nn.init.normal_(module.position_embedding.weight, std=self.config.initializer_range)
if isinstance(module, nn.Linear):
# Slightly different from the TF version which uses truncated_normal for initialization
# cf https://github.com/pytorch/pytorch/pull/5617
module.weight.data.normal_(mean=0.0, std=self.config.initializer_range)
if module.bias is not None:
module.bias.data.zero_()
elif isinstance(module, nn.Embedding):
module.weight.data.normal_(mean=0.0, std=self.config.initializer_range)
if module.padding_idx is not None:
module.weight.data[module.padding_idx].zero_()
elif isinstance(module, nn.LayerNorm):
module.bias.data.zero_()
module.weight.data.fill_(1.0)
# Copied from transformers.models.clip.modeling_clip.CLIPVisionEmbeddings with CLIP->Git
class GitVisionEmbeddings(nn.Module):
def __init__(self, config: GitVisionConfig):
super().__init__()
self.config = config
self.embed_dim = config.hidden_size
self.image_size = config.image_size
self.patch_size = config.patch_size
self.class_embedding = nn.Parameter(torch.randn(self.embed_dim))
self.patch_embedding = nn.Conv2d(
in_channels=config.num_channels,
out_channels=self.embed_dim,
kernel_size=self.patch_size,
stride=self.patch_size,
bias=False,
)
self.num_patches = (self.image_size // self.patch_size) ** 2
self.num_positions = self.num_patches + 1
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.
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
position_embedding = self.position_embedding.weight.unsqueeze(0)
num_positions = position_embedding.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_embedding(self.position_ids)
class_pos_embed = position_embedding[:, :1]
patch_pos_embed = position_embedding[:, 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.FloatTensor, interpolate_pos_encoding=False) -> torch.Tensor:
batch_size, _, height, width = pixel_values.shape
if not interpolate_pos_encoding and (height != self.image_size or width != self.image_size):
raise ValueError(
f"Input image size ({height}*{width}) doesn't match model ({self.image_size}*{self.image_size})."
)
target_dtype = self.patch_embedding.weight.dtype
patch_embeds = self.patch_embedding(pixel_values.to(dtype=target_dtype)) # shape = [*, width, grid, grid]
patch_embeds = patch_embeds.flatten(2).transpose(1, 2)
class_embeds = self.class_embedding.expand(batch_size, 1, -1)
embeddings = torch.cat([class_embeds, patch_embeds], dim=1)
if interpolate_pos_encoding:
embeddings = embeddings + self.interpolate_pos_encoding(embeddings, height, width)
else:
embeddings = embeddings + self.position_embedding(self.position_ids)
return embeddings
class GitVisionMLP(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
# Copied from transformers.models.siglip.modeling_siglip.eager_attention_forward
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 GitVisionAttention(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,
causal_attention_mask: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = False,
) -> 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)
# CLIP text model uses both `causal_attention_mask` and `attention_mask`
# in case FA2 kernel is called, `is_causal` should be inferred from `causal_attention_mask`
if self.config._attn_implementation != "flash_attention_2":
if attention_mask is not None and causal_attention_mask is not None:
attention_mask = attention_mask + causal_attention_mask
elif causal_attention_mask is not None:
attention_mask = causal_attention_mask
else:
self.is_causal = causal_attention_mask is not None
attention_interface: Callable = eager_attention_forward
if self.config._attn_implementation != "eager":
if self.config._attn_implementation == "sdpa" and output_attentions:
logger.warning_once(
"`torch.nn.functional.scaled_dot_product_attention` does not support `output_attentions=True`. Falling back to "
'eager attention. This warning can be removed using the argument `attn_implementation="eager"` when loading the model.'
)
else:
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)
if not output_attentions:
attn_weights = None
return attn_output, attn_weights
# Copied from transformers.models.altclip.modeling_altclip.AltCLIPEncoderLayer with AltCLIP->GitVision
class GitVisionEncoderLayer(GradientCheckpointingLayer):
def __init__(self, config: GitVisionConfig):
super().__init__()
self.embed_dim = config.hidden_size
self.self_attn = GitVisionAttention(config)
self.layer_norm1 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
self.mlp = GitVisionMLP(config)
self.layer_norm2 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.Tensor,
causal_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 size
`(batch, 1, tgt_len, src_len)` where padding elements are indicated by very large negative values.
`(config.encoder_attention_heads,)`.
output_attentions (`bool`, *optional*):
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,
causal_attention_mask=causal_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
# Copied from transformers.models.altclip.modeling_altclip.AltCLIPEncoder with AltCLIP->GitVision, CLIPConfig
class GitVisionEncoder(nn.Module):
"""
Transformer encoder consisting of `config.num_hidden_layers` self attention layers. Each layer is a
[`GitVisionEncoderLayer`].
Args:
config: GitVisionConfig
"""
def __init__(self, config: GitVisionConfig):
super().__init__()
self.config = config
self.layers = nn.ModuleList([GitVisionEncoderLayer(config) for _ in range(config.num_hidden_layers)])
self.gradient_checkpointing = False
@can_return_tuple
def forward(
self,
inputs_embeds,
attention_mask: Optional[torch.Tensor] = None,
causal_attention_mask: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
) -> Union[tuple, 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)
causal_attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
Causal mask for the text model. 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
)
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
encoder_states = () if output_hidden_states else None
all_attentions = () if output_attentions else None
hidden_states = inputs_embeds
for idx, encoder_layer in enumerate(self.layers):
if output_hidden_states:
encoder_states = encoder_states + (hidden_states,)
layer_outputs = encoder_layer(
hidden_states,
attention_mask,
causal_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 GitVisionTransformer(nn.Module):
# Copied from transformers.models.altclip.modeling_altclip.AltCLIPVisionTransformer.__init__ with AltCLIPEncoder->GitVisionEncoder, AltCLIP->Git
def __init__(self, config: GitVisionConfig):
super().__init__()
self.config = config
embed_dim = config.hidden_size
self.embeddings = GitVisionEmbeddings(config)
self.pre_layrnorm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)
self.encoder = GitVisionEncoder(config)
self.post_layernorm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)
@auto_docstring
def forward(
self,
pixel_values: Optional[torch.FloatTensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
interpolate_pos_encoding: Optional[bool] = False,
return_dict: Optional[bool] = None,
) -> Union[tuple, BaseModelOutput]:
output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
output_hidden_states = (
output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
)
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
if pixel_values is None:
raise ValueError("You have to specify pixel_values")
hidden_states = self.embeddings(pixel_values, interpolate_pos_encoding=interpolate_pos_encoding)
hidden_states = self.pre_layrnorm(hidden_states)
encoder_outputs = self.encoder(
inputs_embeds=hidden_states,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
last_hidden_state = encoder_outputs[0]
last_hidden_state = self.post_layernorm(last_hidden_state)
if not return_dict:
return (last_hidden_state,) + encoder_outputs[1:]
return BaseModelOutput(
last_hidden_state=last_hidden_state,
hidden_states=encoder_outputs.hidden_states,
attentions=encoder_outputs.attentions,
)
@auto_docstring(
custom_intro="""
The vision model from CLIP, used in GIT, without any head or projection on top.
"""
)
class GitVisionModel(GitPreTrainedModel):
config: GitVisionConfig
main_input_name = "pixel_values"
# Copied from transformers.models.clip.modeling_clip.CLIPVisionModel.__init__ with CLIP->Git
def __init__(self, config: GitVisionConfig):
super().__init__(config)
self.vision_model = GitVisionTransformer(config)
# Initialize weights and apply final processing
self.post_init()
def get_input_embeddings(self) -> nn.Module:
return self.vision_model.embeddings.patch_embedding
@auto_docstring
def forward(
self,
pixel_values: Optional[torch.FloatTensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
interpolate_pos_encoding: bool = False,
return_dict: Optional[bool] = None,
) -> Union[tuple, BaseModelOutput]:
r"""
Examples:
```python
>>> from PIL import Image
>>> import requests
>>> from transformers import AutoProcessor, GitVisionModel
>>> processor = AutoProcessor.from_pretrained("microsoft/git-base")
>>> model = GitVisionModel.from_pretrained("microsoft/git-base")
>>> 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
```"""
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
return self.vision_model(
pixel_values=pixel_values,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
interpolate_pos_encoding=interpolate_pos_encoding,
return_dict=return_dict,
)
class GitProjection(nn.Module):
def __init__(self, config: GitConfig):
super().__init__()
self.config = config
self.visual_projection = nn.Sequential(
nn.Linear(config.vision_config.hidden_size, config.hidden_size),
nn.LayerNorm(config.hidden_size, eps=config.vision_config.layer_norm_eps),
)
def forward(self, embeddings: torch.Tensor) -> torch.Tensor:
return self.visual_projection(embeddings)
@auto_docstring(
custom_intro="""
The bare GIT Model transformer consisting of a CLIP image encoder and text decoder outputting raw hidden-states
"""
)
class GitModel(GitPreTrainedModel):
def __init__(self, config):
super().__init__(config)
self.config = config
self.embeddings = GitEmbeddings(config)
self.image_encoder = GitVisionModel(config.vision_config)
self.encoder = GitEncoder(config)
self.visual_projection = GitProjection(config)
if config.num_image_with_embedding is not None:
self.img_temperal_embedding = nn.ParameterList(
nn.Parameter(torch.zeros(1, 1, config.vision_config.hidden_size))
for _ in range(config.num_image_with_embedding)
)
# Initialize weights and apply final processing
self.post_init()
def get_input_embeddings(self):
return self.embeddings.word_embeddings
def set_input_embeddings(self, value):
self.embeddings.word_embeddings = value
def _prune_heads(self, heads_to_prune):
"""
Prunes heads of the model. heads_to_prune: dict of {layer_num: list of heads to prune in this layer} See base
class PreTrainedModel
"""
for layer, heads in heads_to_prune.items():
self.encoder.layer[layer].attention.prune_heads(heads)
def _generate_future_mask(self, size: int, dtype: torch.dtype, device: torch.device) -> torch.Tensor:
# Default mask is for forward direction. Flip for backward direction.
mask = torch.triu(torch.ones(size, size, device=device, dtype=dtype), diagonal=1)
mask = mask.masked_fill(mask == 1, float("-inf"))
return mask
def create_attention_mask(self, tgt, memory, tgt_mask, past_key_values_length, memory_key_padding_mask=None):
num_tgt = tgt.shape[1]
num_memory = memory.shape[1]
device = tgt.device
dtype = tgt.dtype
top_left = torch.zeros((num_memory, num_memory), device=device, dtype=dtype)
top_right = torch.full(
(num_memory, num_tgt + past_key_values_length),
float("-inf"),
device=tgt.device,
dtype=dtype,
)
bottom_left = torch.zeros(
(num_tgt, num_memory),
dtype=dtype,
device=tgt_mask.device,
)
if past_key_values_length > 0:
tgt_mask = torch.zeros(
(tgt_mask.shape[0], tgt_mask.shape[0] + past_key_values_length),
dtype=dtype,
device=tgt_mask.device,
)
left = torch.cat((top_left, bottom_left), dim=0)
right = torch.cat((top_right, tgt_mask.to(dtype)), dim=0)
full_attention_mask = torch.cat((left, right), dim=1)[None, :]
if memory_key_padding_mask is None:
memory_key_padding_mask = torch.full((memory.shape[0], memory.shape[1]), fill_value=False, device=device)
# if it is False, it means valid. That is, it is not a padding
if memory_key_padding_mask.dtype != torch.bool:
raise ValueError("Memory key padding mask must be a boolean tensor.")
zero_negative_infinity = torch.zeros_like(memory_key_padding_mask, dtype=tgt.dtype)
zero_negative_infinity[memory_key_padding_mask] = float("-inf")
full_attention_mask = full_attention_mask.expand(
(memory_key_padding_mask.shape[0], num_memory + num_tgt, num_memory + past_key_values_length + num_tgt)
)
full_attention_mask = full_attention_mask.clone()
origin_left = full_attention_mask[:, :, :num_memory]
update = zero_negative_infinity[:, None, :]
full_attention_mask[:, :, :num_memory] = origin_left + update
# add axis for multi-head
full_attention_mask = full_attention_mask[:, None, :, :]
return full_attention_mask
@auto_docstring
def forward(
self,
input_ids: Optional[torch.Tensor] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.Tensor] = None,
pixel_values: Optional[torch.Tensor] = None,
head_mask: Optional[torch.Tensor] = None,
inputs_embeds: Optional[torch.Tensor] = None,
past_key_values: Optional[Union[Cache, list[torch.FloatTensor]]] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
interpolate_pos_encoding: bool = False,
return_dict: Optional[bool] = None,
) -> Union[tuple[torch.Tensor], BaseModelOutputWithPooling]:
r"""
Examples:
```python
>>> from transformers import AutoProcessor, AutoModel
>>> import requests
>>> from PIL import Image
>>> processor = AutoProcessor.from_pretrained("microsoft/git-base")
>>> model = AutoModel.from_pretrained("microsoft/git-base")
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> image = Image.open(requests.get(url, stream=True).raw)
>>> text = "this is an image of two cats"
>>> inputs = processor(images=image, text=text, return_tensors="pt")
>>> outputs = model(**inputs)
>>> last_hidden_state = outputs.last_hidden_state
```"""
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
)
use_cache = use_cache if use_cache is not None else self.config.use_cache
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
if input_ids is not None and inputs_embeds is not None:
raise ValueError("You cannot specify both input_ids and inputs_embeds at the same time")
elif input_ids is not None:
self.warn_if_padding_and_no_attention_mask(input_ids, attention_mask)
input_shape = input_ids.size()
elif inputs_embeds is not None:
input_shape = inputs_embeds.size()[:-1]
else:
raise ValueError("You have to specify either input_ids or inputs_embeds")
seq_length = input_shape[1]
# past_key_values_length
past_key_values_length = 0
if past_key_values is not None:
past_key_values_length = (
past_key_values.get_seq_length()
if not isinstance(past_key_values, Cache)
else past_key_values.get_seq_length()
)
# Prepare head mask if needed
# 1.0 in head_mask indicate we keep the head
# attention_probs has shape bsz x n_heads x N x N
# input head_mask has shape [num_heads] or [num_hidden_layers x num_heads]
# and head_mask is converted to shape [num_hidden_layers x batch x num_heads x seq_length x seq_length]
head_mask = self.get_head_mask(head_mask, self.config.num_hidden_layers)
projected_visual_features = None
if pixel_values is not None:
if pixel_values.ndim == 4:
# here we assume pixel_values is of shape (batch_size, num_channels, height, width)
visual_features = self.image_encoder(
pixel_values, interpolate_pos_encoding=interpolate_pos_encoding
).last_hidden_state
elif pixel_values.ndim == 5:
# here we assume pixel_values is of shape (batch_size, num_frames, num_channels, height, width)
visual_features = []
for frame_idx in range(pixel_values.shape[1]):
visual_features_frame = self.image_encoder(
pixel_values[:, frame_idx, :, :], interpolate_pos_encoding=interpolate_pos_encoding
).last_hidden_state
visual_features_frame += self.img_temperal_embedding[frame_idx]
visual_features.append(visual_features_frame)
# finally, concatenate all features along sequence dimension
visual_features = torch.cat(visual_features, dim=1)
else:
raise ValueError("pixel_values must be of rank 4 or 5")
projected_visual_features = self.visual_projection(visual_features)
embedding_output = self.embeddings(
input_ids=input_ids,
position_ids=position_ids,
inputs_embeds=inputs_embeds,
past_key_values_length=past_key_values_length,
)
if projected_visual_features is None:
projected_visual_features = torch.zeros(
(embedding_output.shape[0], 0, embedding_output.shape[2]),
dtype=embedding_output.dtype,
device=embedding_output.device,
)
# Repeat visual features to match embedding batch size.
projected_visual_features = projected_visual_features.repeat(
embedding_output.size(0) // projected_visual_features.size(0), 1, 1
)
# concatenate patch token and text token embeddings
hidden_states = torch.cat((projected_visual_features, embedding_output), dim=1)
# By default, an additive causal mask is created
# for masking the future (one direction).
tgt_mask = self._generate_future_mask(seq_length, embedding_output.dtype, embedding_output.device)
# Create an attention mask of shape (batch_size, 1, tgt_seq_len, src_seq_len)
combined_attention_mask = self.create_attention_mask(
tgt=embedding_output,
memory=projected_visual_features,
tgt_mask=tgt_mask,
past_key_values_length=past_key_values_length,
)
if attention_mask is not None:
# if the user provides an attention mask, we add it to the default one
# [bsz, seq_len] -> [bsz, 1, tgt_seq_len, src_seq_len]
expanded_attn_mask = _prepare_4d_attention_mask(
attention_mask, embedding_output.dtype, tgt_len=input_shape[-1]
).to(embedding_output.device)
if past_key_values_length > 0:
expanded_attn_mask = expanded_attn_mask[:, :, -past_key_values_length:, :]
else:
combined_attention_mask[:, :, -input_shape[1] :, -input_shape[1] :] += expanded_attn_mask
encoder_outputs = self.encoder(
hidden_states,
attention_mask=combined_attention_mask,
head_mask=head_mask,
past_key_values=past_key_values,
use_cache=use_cache,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
pixel_values_present=pixel_values is not None,
)
sequence_output = encoder_outputs[0]
if not return_dict:
return (sequence_output,) + encoder_outputs[1:]
return BaseModelOutputWithPast(
last_hidden_state=sequence_output,
past_key_values=encoder_outputs.past_key_values,
hidden_states=encoder_outputs.hidden_states,
attentions=encoder_outputs.attentions,
)
@auto_docstring(
custom_intro="""
GIT Model with a `language modeling` head on top for autoregressive language modeling.
"""
)
class GitForCausalLM(GitPreTrainedModel, GenerationMixin):
_tied_weights_keys = ["output.weight"]
def __init__(self, config):
super().__init__(config)
self.git = GitModel(config)
self.output = nn.Linear(config.hidden_size, config.vocab_size)
# Initialize weights and apply final processing
self.post_init()
def get_output_embeddings(self):
return self.output
def set_output_embeddings(self, new_embeddings):
self.output = new_embeddings
@auto_docstring
def forward(
self,
input_ids: Optional[torch.Tensor] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.Tensor] = None,
pixel_values: Optional[torch.Tensor] = None,
head_mask: Optional[torch.Tensor] = None,
inputs_embeds: Optional[torch.Tensor] = None,
labels: Optional[torch.Tensor] = None,
past_key_values: Optional[Union[Cache, list[torch.Tensor]]] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
interpolate_pos_encoding: bool = False,
return_dict: Optional[bool] = None,
**kwargs,
) -> Union[tuple[torch.Tensor], CausalLMOutputWithPast]:
r"""
labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Labels for computing the left-to-right language modeling loss (next word prediction). Indices should be in
`[-100, 0, ..., config.vocab_size]` (see `input_ids` docstring) Tokens with indices set to `-100` are
ignored (masked), the loss is only computed for the tokens with labels n `[0, ..., config.vocab_size]`
Examples:
Image captioning example:
```python
>>> from transformers import AutoProcessor, AutoModelForCausalLM
>>> import requests
>>> from PIL import Image
>>> processor = AutoProcessor.from_pretrained("microsoft/git-base-coco")
>>> model = AutoModelForCausalLM.from_pretrained("microsoft/git-base-coco")
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> image = Image.open(requests.get(url, stream=True).raw)
>>> pixel_values = processor(images=image, return_tensors="pt").pixel_values
>>> generated_ids = model.generate(pixel_values=pixel_values, max_length=50)
>>> generated_caption = processor.batch_decode(generated_ids, skip_special_tokens=True)[0]
>>> print(generated_caption)
two cats sleeping on a pink blanket next to remotes.
```
Visual question answering (VQA) example:
```python
>>> from transformers import AutoProcessor, AutoModelForCausalLM
>>> from huggingface_hub import hf_hub_download
>>> from PIL import Image
>>> processor = AutoProcessor.from_pretrained("microsoft/git-base-textvqa")
>>> model = AutoModelForCausalLM.from_pretrained("microsoft/git-base-textvqa")
>>> file_path = hf_hub_download(repo_id="nielsr/textvqa-sample", filename="bus.png", repo_type="dataset")
>>> image = Image.open(file_path).convert("RGB")
>>> pixel_values = processor(images=image, return_tensors="pt").pixel_values
>>> question = "what does the front of the bus say at the top?"
>>> input_ids = processor(text=question, add_special_tokens=False).input_ids
>>> input_ids = [processor.tokenizer.cls_token_id] + input_ids
>>> input_ids = torch.tensor(input_ids).unsqueeze(0)
>>> generated_ids = model.generate(pixel_values=pixel_values, input_ids=input_ids, max_length=50)
>>> print(processor.batch_decode(generated_ids, skip_special_tokens=True))
['what does the front of the bus say at the top? special']
```
Video captioning example:
```python
>>> import av
>>> import numpy as np
>>> from PIL import Image
>>> from huggingface_hub import hf_hub_download
>>> from transformers import AutoProcessor, AutoModelForCausalLM
>>> processor = AutoProcessor.from_pretrained("microsoft/git-base-vatex")
>>> model = AutoModelForCausalLM.from_pretrained("microsoft/git-base-vatex")
>>> # set seed for reproducibility
>>> np.random.seed(45)
>>> def read_video_pyav(container, indices):
... '''
... Decode the video with PyAV decoder.
... Args:
... container (`av.container.input.InputContainer`): PyAV container.
... indices (`list[int]`): List of frame indices to decode.
... Returns:
... result (np.ndarray): np array of decoded frames of shape (num_frames, height, width, 3).
... '''
... frames = []
... container.seek(0)
... start_index = indices[0]
... end_index = indices[-1]
... for i, frame in enumerate(container.decode(video=0)):
... if i > end_index:
... break
... if i >= start_index and i in indices:
... frames.append(frame)
... return np.stack([x.to_ndarray(format="rgb24") for x in frames])
>>> def sample_frame_indices(clip_len, frame_sample_rate, seg_len):
... '''
... Sample a given number of frame indices from the video.
... Args:
... clip_len (`int`): Total number of frames to sample.
... frame_sample_rate (`int`): Sample every n-th frame.
... seg_len (`int`): Maximum allowed index of sample's last frame.
... Returns:
... indices (`list[int]`): List of sampled frame indices
... '''
... converted_len = int(clip_len * frame_sample_rate)
... end_idx = np.random.randint(converted_len, seg_len)
... start_idx = end_idx - converted_len
... indices = np.linspace(start_idx, end_idx, num=clip_len)
... indices = np.clip(indices, start_idx, end_idx - 1).astype(np.int64)
... return indices
>>> # load video
>>> file_path = hf_hub_download(
... repo_id="nielsr/video-demo", filename="eating_spaghetti.mp4", repo_type="dataset"
... )
>>> container = av.open(file_path)
>>> # sample frames
>>> num_frames = model.config.num_image_with_embedding
>>> indices = sample_frame_indices(
... clip_len=num_frames, frame_sample_rate=4, seg_len=container.streams.video[0].frames
... )
>>> frames = read_video_pyav(container, indices)
>>> pixel_values = processor(images=list(frames), return_tensors="pt").pixel_values
>>> generated_ids = model.generate(pixel_values=pixel_values, max_length=50)
>>> print("Generated caption:", processor.batch_decode(generated_ids, skip_special_tokens=True))
Generated caption: ['a woman is sitting at a table and she is talking about the food she is holding.']
```
"""
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
if labels is not None:
use_cache = False
outputs = self.git(
input_ids,
attention_mask=attention_mask,
position_ids=position_ids,
pixel_values=pixel_values,
head_mask=head_mask,
inputs_embeds=inputs_embeds,
past_key_values=past_key_values,
use_cache=use_cache,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
interpolate_pos_encoding=interpolate_pos_encoding,
return_dict=return_dict,
)
sequence_output = outputs[0]
logits = self.output(sequence_output)
loss = None
if labels is not None:
# we are doing next-token prediction; shift prediction scores and input ids by one
num_image_tokens = self.git.encoder.layer[0].attention.self.image_patch_tokens
shifted_logits = logits[:, num_image_tokens:-1, :].contiguous()
labels = labels[:, 1:].contiguous()
loss = self.loss_function(
shifted_logits.view(-1, self.config.vocab_size),
labels.view(-1),
vocab_size=self.config.vocab_size,
**kwargs,
)
if not return_dict:
output = (logits,) + outputs[1:]
return ((loss,) + output) if loss is not None else output
return CausalLMOutputWithPast(
loss=loss,
logits=logits,
past_key_values=outputs.past_key_values,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
def prepare_inputs_for_generation(
self, input_ids, past_key_values=None, attention_mask=None, use_cache=None, **kwargs
):
# Overwritten -- `git` has special cache handling and doesn't support generating from `inputs_embeds` atm
# cut decoder_input_ids if past_key_values is used
if past_key_values is not None:
past_length = past_key_values.get_seq_length()
# Some generation methods already pass only the last input ID
if input_ids.shape[1] > past_length:
remove_prefix_length = past_length
else:
# Default to old behavior: keep only final ID
remove_prefix_length = input_ids.shape[1] - 1
input_ids = input_ids[:, remove_prefix_length:]
# if model is used as a decoder in encoder-decoder model, the decoder attention mask is created on the fly
input_shape = input_ids.shape
if attention_mask is None:
attention_mask = input_ids.new_ones(input_shape)
return {
"input_ids": input_ids,
"attention_mask": attention_mask,
"pixel_values": kwargs.get("pixel_values", None),
"past_key_values": past_key_values,
"use_cache": use_cache,
}
__all__ = ["GitForCausalLM", "GitModel", "GitPreTrainedModel", "GitVisionModel"]