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

1048 lines
43 KiB
Python

# coding=utf-8
# Copyright 2022 Multimedia Computing Group, Nanjing University 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 VideoMAE (masked autoencoder) model."""
import collections.abc
from copy import deepcopy
from dataclasses import dataclass
from typing import Callable, Optional, Union
import numpy as np
import torch
import torch.utils.checkpoint
from torch import nn
from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss
from ...activations import ACT2FN
from ...modeling_layers import GradientCheckpointingLayer
from ...modeling_outputs import BaseModelOutput, ImageClassifierOutput
from ...modeling_utils import ALL_ATTENTION_FUNCTIONS, PreTrainedModel
from ...pytorch_utils import find_pruneable_heads_and_indices, prune_linear_layer
from ...utils import (
ModelOutput,
auto_docstring,
logging,
)
from ...utils.constants import IMAGENET_DEFAULT_MEAN, IMAGENET_DEFAULT_STD
from .configuration_videomae import VideoMAEConfig
logger = logging.get_logger(__name__)
@dataclass
@auto_docstring(
custom_intro="""
Class for VideoMAEDecoder's outputs, with potential hidden states and attentions.
"""
)
class VideoMAEDecoderOutput(ModelOutput):
r"""
logits (`torch.FloatTensor` of shape `(batch_size, patch_size ** 2 * num_channels)`):
Pixel reconstruction logits.
"""
logits: Optional[torch.FloatTensor] = None
hidden_states: Optional[tuple[torch.FloatTensor]] = None
attentions: Optional[tuple[torch.FloatTensor]] = None
@dataclass
@auto_docstring(
custom_intro="""
Class for VideoMAEForPreTraining's outputs, with potential hidden states and attentions.
"""
)
class VideoMAEForPreTrainingOutput(ModelOutput):
r"""
loss (`torch.FloatTensor` of shape `(1,)`):
Pixel reconstruction loss.
logits (`torch.FloatTensor` of shape `(batch_size, patch_size ** 2 * num_channels)`):
Pixel reconstruction logits.
"""
loss: Optional[torch.FloatTensor] = None
logits: Optional[torch.FloatTensor] = None
hidden_states: Optional[tuple[torch.FloatTensor]] = None
attentions: Optional[tuple[torch.FloatTensor]] = None
# sin-cos position encoding
# https://github.com/jadore801120/attention-is-all-you-need-pytorch/blob/master/transformer/Models.py#L31
def get_sinusoid_encoding_table(n_position, d_hid):
"""Sinusoid position encoding table"""
# TODO: make it with torch instead of numpy
def get_position_angle_vec(position):
return [position / np.power(10000, 2 * (hid_j // 2) / d_hid) for hid_j in range(d_hid)]
sinusoid_table = np.array([get_position_angle_vec(pos_i) for pos_i in range(n_position)])
sinusoid_table[:, 0::2] = np.sin(sinusoid_table[:, 0::2]) # dim 2i
sinusoid_table[:, 1::2] = np.cos(sinusoid_table[:, 1::2]) # dim 2i+1
return torch.FloatTensor(sinusoid_table).unsqueeze(0)
class VideoMAEEmbeddings(nn.Module):
"""
Construct the patch and position embeddings.
"""
def __init__(self, config):
super().__init__()
self.patch_embeddings = VideoMAEPatchEmbeddings(config)
self.num_patches = self.patch_embeddings.num_patches
# fixed sin-cos embedding
self.position_embeddings = get_sinusoid_encoding_table(self.num_patches, config.hidden_size)
self.config = config
def forward(self, pixel_values, bool_masked_pos):
# create patch embeddings
embeddings = self.patch_embeddings(pixel_values)
# add position embeddings
embeddings = embeddings + self.position_embeddings.detach().type_as(embeddings).to(
device=embeddings.device, copy=True
)
# only keep visible patches
# ~bool_masked_pos means visible
if bool_masked_pos is not None:
batch_size, _, num_channels = embeddings.shape
embeddings = embeddings[~bool_masked_pos]
embeddings = embeddings.reshape(batch_size, -1, num_channels)
return embeddings
class VideoMAEPatchEmbeddings(nn.Module):
"""
Video to Patch Embedding. This module turns a batch of videos of shape (batch_size, num_frames, num_channels,
height, width) into a tensor of shape (batch_size, seq_len, hidden_size) to be consumed by a Transformer encoder.
The seq_len (the number of patches) equals (number of frames // tubelet_size) * (height // patch_size) * (width //
patch_size).
"""
def __init__(self, config):
super().__init__()
image_size = config.image_size
patch_size = config.patch_size
num_channels = config.num_channels
hidden_size = config.hidden_size
num_frames = config.num_frames
tubelet_size = config.tubelet_size
image_size = image_size if isinstance(image_size, collections.abc.Iterable) else (image_size, image_size)
patch_size = patch_size if isinstance(patch_size, collections.abc.Iterable) else (patch_size, patch_size)
self.image_size = image_size
self.patch_size = patch_size
self.tubelet_size = int(tubelet_size)
num_patches = (
(image_size[1] // patch_size[1]) * (image_size[0] // patch_size[0]) * (num_frames // self.tubelet_size)
)
self.num_channels = num_channels
self.num_patches = num_patches
self.projection = nn.Conv3d(
in_channels=num_channels,
out_channels=hidden_size,
kernel_size=(self.tubelet_size, patch_size[0], patch_size[1]),
stride=(self.tubelet_size, patch_size[0], patch_size[1]),
)
def forward(self, pixel_values):
batch_size, num_frames, num_channels, height, width = pixel_values.shape
if num_channels != self.num_channels:
raise ValueError(
"Make sure that the channel dimension of the pixel values match with the one set in the configuration."
)
if height != self.image_size[0] or width != self.image_size[1]:
raise ValueError(
f"Input image size ({height}*{width}) doesn't match model ({self.image_size[0]}*{self.image_size[1]})."
)
# permute to (batch_size, num_channels, num_frames, height, width)
pixel_values = pixel_values.permute(0, 2, 1, 3, 4)
embeddings = self.projection(pixel_values).flatten(2).transpose(1, 2)
return embeddings
# Copied from transformers.models.vit.modeling_vit.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,
):
# Take the dot product between "query" and "key" to get the raw attention scores.
attn_weights = torch.matmul(query, key.transpose(-1, -2)) * scaling
# Normalize the attention scores to probabilities.
attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(query.dtype)
# This is actually dropping out entire tokens to attend to, which might
# seem a bit unusual, but is taken from the original Transformer paper.
attn_weights = nn.functional.dropout(attn_weights, p=dropout, training=module.training)
# Mask heads if we want to
if attention_mask is not None:
attn_weights = attn_weights * attention_mask
attn_output = torch.matmul(attn_weights, value)
attn_output = attn_output.transpose(1, 2).contiguous()
return attn_output, attn_weights
class VideoMAESelfAttention(nn.Module):
def __init__(self, config: VideoMAEConfig) -> 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.config = config
self.num_attention_heads = config.num_attention_heads
self.attention_head_size = int(config.hidden_size / config.num_attention_heads)
self.all_head_size = self.num_attention_heads * self.attention_head_size
self.dropout_prob = config.attention_probs_dropout_prob
self.scaling = self.attention_head_size**-0.5
self.is_causal = False
self.query = nn.Linear(config.hidden_size, self.all_head_size, bias=False)
self.key = nn.Linear(config.hidden_size, self.all_head_size, bias=False)
self.value = nn.Linear(config.hidden_size, self.all_head_size, bias=False)
if config.qkv_bias:
self.q_bias = nn.Parameter(torch.zeros(self.all_head_size))
self.v_bias = nn.Parameter(torch.zeros(self.all_head_size))
else:
self.q_bias = None
self.v_bias = None
def forward(
self, hidden_states, head_mask: Optional[torch.Tensor] = None, output_attentions: bool = False
) -> Union[tuple[torch.Tensor, torch.Tensor], tuple[torch.Tensor]]:
batch_size, seq_length, _ = hidden_states.shape
k_bias = torch.zeros_like(self.v_bias, requires_grad=False) if self.q_bias is not None else None
keys = nn.functional.linear(input=hidden_states, weight=self.key.weight, bias=k_bias)
values = nn.functional.linear(input=hidden_states, weight=self.value.weight, bias=self.v_bias)
queries = nn.functional.linear(input=hidden_states, weight=self.query.weight, bias=self.q_bias)
key_layer = keys.view(batch_size, -1, self.num_attention_heads, self.attention_head_size).transpose(1, 2)
value_layer = values.view(batch_size, -1, self.num_attention_heads, self.attention_head_size).transpose(1, 2)
query_layer = queries.view(batch_size, -1, self.num_attention_heads, self.attention_head_size).transpose(1, 2)
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]
context_layer, attention_probs = attention_interface(
self,
query_layer,
key_layer,
value_layer,
head_mask,
is_causal=self.is_causal,
scaling=self.scaling,
dropout=0.0 if not self.training else self.dropout_prob,
)
new_context_layer_shape = context_layer.size()[:-2] + (self.all_head_size,)
context_layer = context_layer.reshape(new_context_layer_shape)
outputs = (context_layer, attention_probs) if output_attentions else (context_layer,)
return outputs
# Copied from transformers.models.vit.modeling_vit.ViTSelfOutput with ViT->VideoMAE
class VideoMAESelfOutput(nn.Module):
"""
The residual connection is defined in VideoMAELayer instead of here (as is the case with other models), due to the
layernorm applied before each block.
"""
def __init__(self, config: VideoMAEConfig) -> None:
super().__init__()
self.dense = nn.Linear(config.hidden_size, config.hidden_size)
self.dropout = nn.Dropout(config.hidden_dropout_prob)
def forward(self, hidden_states: torch.Tensor, input_tensor: torch.Tensor) -> torch.Tensor:
hidden_states = self.dense(hidden_states)
hidden_states = self.dropout(hidden_states)
return hidden_states
# Copied from transformers.models.vit.modeling_vit.ViTAttention with ViT->VideoMAE
class VideoMAEAttention(nn.Module):
def __init__(self, config: VideoMAEConfig) -> None:
super().__init__()
self.attention = VideoMAESelfAttention(config)
self.output = VideoMAESelfOutput(config)
self.pruned_heads = set()
def prune_heads(self, heads: set[int]) -> None:
if len(heads) == 0:
return
heads, index = find_pruneable_heads_and_indices(
heads, self.attention.num_attention_heads, self.attention.attention_head_size, self.pruned_heads
)
# Prune linear layers
self.attention.query = prune_linear_layer(self.attention.query, index)
self.attention.key = prune_linear_layer(self.attention.key, index)
self.attention.value = prune_linear_layer(self.attention.value, index)
self.output.dense = prune_linear_layer(self.output.dense, index, dim=1)
# Update hyper params and store pruned heads
self.attention.num_attention_heads = self.attention.num_attention_heads - len(heads)
self.attention.all_head_size = self.attention.attention_head_size * self.attention.num_attention_heads
self.pruned_heads = self.pruned_heads.union(heads)
def forward(
self,
hidden_states: torch.Tensor,
head_mask: Optional[torch.Tensor] = None,
output_attentions: bool = False,
) -> Union[tuple[torch.Tensor, torch.Tensor], tuple[torch.Tensor]]:
self_outputs = self.attention(hidden_states, head_mask, output_attentions)
attention_output = self.output(self_outputs[0], hidden_states)
outputs = (attention_output,) + self_outputs[1:] # add attentions if we output them
return outputs
# Copied from transformers.models.vit.modeling_vit.ViTIntermediate ViT->VideoMAE
class VideoMAEIntermediate(nn.Module):
def __init__(self, config: VideoMAEConfig) -> None:
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.vit.modeling_vit.ViTOutput ViT->VideoMAE
class VideoMAEOutput(nn.Module):
def __init__(self, config: VideoMAEConfig) -> None:
super().__init__()
self.dense = nn.Linear(config.intermediate_size, config.hidden_size)
self.dropout = nn.Dropout(config.hidden_dropout_prob)
def forward(self, hidden_states: torch.Tensor, input_tensor: torch.Tensor) -> torch.Tensor:
hidden_states = self.dense(hidden_states)
hidden_states = self.dropout(hidden_states)
hidden_states = hidden_states + input_tensor
return hidden_states
# Copied from transformers.models.vit.modeling_vit.ViTLayer with ViT->VideoMAE,VIT->VIDEOMAE
class VideoMAELayer(GradientCheckpointingLayer):
"""This corresponds to the Block class in the timm implementation."""
def __init__(self, config: VideoMAEConfig) -> None:
super().__init__()
self.chunk_size_feed_forward = config.chunk_size_feed_forward
self.seq_len_dim = 1
self.attention = VideoMAEAttention(config)
self.intermediate = VideoMAEIntermediate(config)
self.output = VideoMAEOutput(config)
self.layernorm_before = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.layernorm_after = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
def forward(
self,
hidden_states: torch.Tensor,
head_mask: Optional[torch.Tensor] = None,
output_attentions: bool = False,
) -> Union[tuple[torch.Tensor, torch.Tensor], tuple[torch.Tensor]]:
self_attention_outputs = self.attention(
self.layernorm_before(hidden_states), # in VideoMAE, layernorm is applied before self-attention
head_mask,
output_attentions=output_attentions,
)
attention_output = self_attention_outputs[0]
outputs = self_attention_outputs[1:] # add self attentions if we output attention weights
# first residual connection
hidden_states = attention_output + hidden_states
# in VideoMAE, layernorm is also applied after self-attention
layer_output = self.layernorm_after(hidden_states)
layer_output = self.intermediate(layer_output)
# second residual connection is done here
layer_output = self.output(layer_output, hidden_states)
outputs = (layer_output,) + outputs
return outputs
# Copied from transformers.models.vit.modeling_vit.ViTEncoder with ViT->VideoMAE
class VideoMAEEncoder(nn.Module):
def __init__(self, config: VideoMAEConfig) -> None:
super().__init__()
self.config = config
self.layer = nn.ModuleList([VideoMAELayer(config) for _ in range(config.num_hidden_layers)])
self.gradient_checkpointing = False
def forward(
self,
hidden_states: torch.Tensor,
head_mask: Optional[torch.Tensor] = None,
output_attentions: bool = False,
output_hidden_states: bool = False,
return_dict: bool = True,
) -> Union[tuple, BaseModelOutput]:
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, layer_head_mask, output_attentions)
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, all_hidden_states, all_self_attentions] if v is not None)
return BaseModelOutput(
last_hidden_state=hidden_states,
hidden_states=all_hidden_states,
attentions=all_self_attentions,
)
@auto_docstring
class VideoMAEPreTrainedModel(PreTrainedModel):
config: VideoMAEConfig
base_model_prefix = "videomae"
main_input_name = "pixel_values"
supports_gradient_checkpointing = True
_supports_sdpa = True
_supports_flash_attn = True
_supports_flex_attn = True
_supports_attention_backend = True
def _init_weights(self, module):
"""Initialize the weights"""
if isinstance(module, (nn.Linear, nn.Conv3d)):
# 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.LayerNorm):
module.bias.data.zero_()
module.weight.data.fill_(1.0)
@auto_docstring
class VideoMAEModel(VideoMAEPreTrainedModel):
def __init__(self, config):
super().__init__(config)
self.config = config
self.embeddings = VideoMAEEmbeddings(config)
self.encoder = VideoMAEEncoder(config)
if config.use_mean_pooling:
self.layernorm = None
else:
self.layernorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
# Initialize weights and apply final processing
self.post_init()
def get_input_embeddings(self):
return self.embeddings.patch_embeddings
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)
@auto_docstring
def forward(
self,
pixel_values: torch.FloatTensor,
bool_masked_pos: Optional[torch.BoolTensor] = None,
head_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"""
bool_masked_pos (`torch.BoolTensor` of shape `(batch_size, sequence_length)`, *optional*):
Boolean masked positions. Indicates which patches are masked (1) and which aren't (0). Each video in the
batch must have the same number of masked patches. If `None`, then all patches are considered. Sequence
length is `(num_frames // tubelet_size) * (image_size // patch_size) ** 2`.
Examples:
```python
>>> import av
>>> import numpy as np
>>> from transformers import AutoImageProcessor, VideoMAEModel
>>> from huggingface_hub import hf_hub_download
>>> np.random.seed(0)
>>> 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
>>> # video clip consists of 300 frames (10 seconds at 30 FPS)
>>> file_path = hf_hub_download(
... repo_id="nielsr/video-demo", filename="eating_spaghetti.mp4", repo_type="dataset"
... )
>>> container = av.open(file_path)
>>> # sample 16 frames
>>> indices = sample_frame_indices(clip_len=16, frame_sample_rate=1, seg_len=container.streams.video[0].frames)
>>> video = read_video_pyav(container, indices)
>>> image_processor = AutoImageProcessor.from_pretrained("MCG-NJU/videomae-base")
>>> model = VideoMAEModel.from_pretrained("MCG-NJU/videomae-base")
>>> # prepare video for the model
>>> inputs = image_processor(list(video), return_tensors="pt")
>>> # forward pass
>>> outputs = model(**inputs)
>>> last_hidden_states = outputs.last_hidden_state
>>> list(last_hidden_states.shape)
[1, 1568, 768]
```"""
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
# 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)
embedding_output = self.embeddings(pixel_values, bool_masked_pos)
encoder_outputs = self.encoder(
embedding_output,
head_mask=head_mask,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
sequence_output = encoder_outputs[0]
if self.layernorm is not None:
sequence_output = self.layernorm(sequence_output)
if not return_dict:
return (sequence_output,) + encoder_outputs[1:]
return BaseModelOutput(
last_hidden_state=sequence_output,
hidden_states=encoder_outputs.hidden_states,
attentions=encoder_outputs.attentions,
)
class VideoMAEDecoder(nn.Module):
def __init__(self, config, num_patches):
super().__init__()
decoder_num_labels = config.num_channels * config.tubelet_size * config.patch_size**2
decoder_config = deepcopy(config)
decoder_config.hidden_size = config.decoder_hidden_size
decoder_config.num_hidden_layers = config.decoder_num_hidden_layers
decoder_config.num_attention_heads = config.decoder_num_attention_heads
decoder_config.intermediate_size = config.decoder_intermediate_size
self.decoder_layers = nn.ModuleList(
[VideoMAELayer(decoder_config) for _ in range(config.decoder_num_hidden_layers)]
)
self.norm = nn.LayerNorm(config.decoder_hidden_size)
self.head = (
nn.Linear(config.decoder_hidden_size, decoder_num_labels) if decoder_num_labels > 0 else nn.Identity()
)
self.gradient_checkpointing = False
self.config = config
def forward(
self,
hidden_states,
return_token_num,
output_attentions=False,
output_hidden_states=False,
return_dict=True,
):
# apply Transformer layers (blocks)
all_hidden_states = () if output_hidden_states else None
all_self_attentions = () if output_attentions else None
for i, layer_module in enumerate(self.decoder_layers):
if output_hidden_states:
all_hidden_states = all_hidden_states + (hidden_states,)
layer_outputs = layer_module(hidden_states, head_mask=None, output_attentions=output_attentions)
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 return_token_num > 0:
hidden_states = hidden_states[:, -return_token_num:]
# predictor projection
hidden_states = self.norm(hidden_states)
logits = self.head(hidden_states)
if not return_dict:
return tuple(v for v in [logits, all_hidden_states, all_self_attentions] if v is not None)
return VideoMAEDecoderOutput(logits=logits, hidden_states=all_hidden_states, attentions=all_self_attentions)
@auto_docstring(
custom_intro="""
The VideoMAE Model transformer with the decoder on top for self-supervised pre-training.
"""
)
class VideoMAEForPreTraining(VideoMAEPreTrainedModel):
def __init__(self, config):
super().__init__(config)
self.config = config
self.videomae = VideoMAEModel(config)
self.encoder_to_decoder = nn.Linear(config.hidden_size, config.decoder_hidden_size, bias=False)
self.mask_token = nn.Parameter(torch.zeros(1, 1, config.decoder_hidden_size))
self.position_embeddings = get_sinusoid_encoding_table(
self.videomae.embeddings.num_patches, config.decoder_hidden_size
)
self.decoder = VideoMAEDecoder(config, num_patches=self.videomae.embeddings.num_patches)
# Initialize weights and apply final processing
self.post_init()
@auto_docstring
def forward(
self,
pixel_values: torch.FloatTensor,
bool_masked_pos: torch.BoolTensor,
head_mask: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
) -> Union[tuple, VideoMAEForPreTrainingOutput]:
r"""
bool_masked_pos (`torch.BoolTensor` of shape `(batch_size, sequence_length)`):
Boolean masked positions. Indicates which patches are masked (1) and which aren't (0). Each video in the
batch must have the same number of masked patches. Sequence length is `(num_frames // tubelet_size) *
(image_size // patch_size) ** 2`.
Examples:
```python
>>> from transformers import AutoImageProcessor, VideoMAEForPreTraining
>>> import numpy as np
>>> import torch
>>> num_frames = 16
>>> video = list(np.random.randint(0, 256, (num_frames, 3, 224, 224)))
>>> image_processor = AutoImageProcessor.from_pretrained("MCG-NJU/videomae-base")
>>> model = VideoMAEForPreTraining.from_pretrained("MCG-NJU/videomae-base")
>>> pixel_values = image_processor(video, return_tensors="pt").pixel_values
>>> num_patches_per_frame = (model.config.image_size // model.config.patch_size) ** 2
>>> seq_length = (num_frames // model.config.tubelet_size) * num_patches_per_frame
>>> bool_masked_pos = torch.randint(0, 2, (1, seq_length)).bool()
>>> outputs = model(pixel_values, bool_masked_pos=bool_masked_pos)
>>> loss = outputs.loss
```"""
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
outputs = self.videomae(
pixel_values,
bool_masked_pos=bool_masked_pos,
head_mask=head_mask,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
sequence_output = outputs[0]
sequence_output = self.encoder_to_decoder(
sequence_output
) # [batch_size, num_visible_patches, decoder_hidden_size]
batch_size, seq_len, num_channels = sequence_output.shape
# we don't unshuffle the correct visible token order, but shuffle the position embeddings accordingly.
if bool_masked_pos is None:
raise ValueError("One must provided a boolean mask ")
expanded_position_embeddings = self.position_embeddings.expand(batch_size, -1, -1).type_as(pixel_values)
expanded_position_embeddings = expanded_position_embeddings.detach().to(device=pixel_values.device, copy=True)
pos_emb_visible = expanded_position_embeddings[~bool_masked_pos].reshape(batch_size, -1, num_channels)
pos_emb_mask = expanded_position_embeddings[bool_masked_pos].reshape(batch_size, -1, num_channels)
# [batch_size, num_patches, decoder_hidden_size]
x_full = torch.cat([sequence_output + pos_emb_visible, self.mask_token + pos_emb_mask], dim=1)
# [batch_size, num_masked_patches, num_channels * patch_size * patch_size]
decoder_outputs = self.decoder(x_full, pos_emb_mask.shape[1])
logits = decoder_outputs.logits
loss = None
with torch.no_grad():
# calculate the labels to be predicted
if self.config.num_channels != 3:
# Can't unnormalize with default means/stds
frames = pixel_values
else:
# first, unnormalize the frames
device = pixel_values.device
dtype = pixel_values.dtype
mean = torch.as_tensor(IMAGENET_DEFAULT_MEAN).to(device=device, dtype=dtype)[None, None, :, None, None]
std = torch.as_tensor(IMAGENET_DEFAULT_STD).to(device=device, dtype=dtype)[None, None, :, None, None]
frames = pixel_values * std + mean # in [0, 1]
batch_size, time, num_channels, height, width = frames.shape
tubelet_size, patch_size = self.config.tubelet_size, self.config.patch_size
if self.config.norm_pix_loss:
# step 1: split up dimensions (time by tubelet_size, height by patch_size, width by patch_size)
frames = frames.view(
batch_size,
time // tubelet_size,
tubelet_size,
num_channels,
height // patch_size,
patch_size,
width // patch_size,
patch_size,
)
# step 2: move dimensions to concatenate:
frames = frames.permute(0, 1, 4, 6, 2, 5, 7, 3).contiguous()
# step 3: concatenate:
frames = frames.view(
batch_size,
time // tubelet_size * height // patch_size * width // patch_size,
tubelet_size * patch_size * patch_size,
num_channels,
)
# step 4: normalize. The authors find that the mean is about 0.48 and standard deviation is about 0.08.
frames_norm = (frames - frames.mean(dim=-2, keepdim=True)) / (
frames.var(dim=-2, unbiased=True, keepdim=True).sqrt() + 1e-6
)
# step 5: reshape to (batch_size, T//ts * H//ps * W//ps, ts * ps * ps * C)
videos_patch = frames_norm.view(
batch_size,
time // tubelet_size * height // patch_size * width // patch_size,
tubelet_size * patch_size * patch_size * num_channels,
)
else:
if self.config.num_channels != 3:
raise ValueError(
"Can't unnormalize non-RGB images. Consider setting config.norm_pix_loss to False."
)
# step 1: split up dimensions (time by tubelet_size, height by patch_size, width by patch_size)
frames = frames.view(
batch_size,
time // tubelet_size,
tubelet_size,
num_channels,
height // patch_size,
patch_size,
width // patch_size,
patch_size,
)
# step 2: move dimensions to concatenate: (batch_size, T//ts, H//ps, W//ps, ts, ps, ps, C)
frames = frames.permute(0, 1, 4, 6, 2, 5, 7, 3).contiguous()
# step 3: concatenate
videos_patch = frames.view(
batch_size,
time // tubelet_size * height // patch_size * width // patch_size,
tubelet_size * patch_size * patch_size * num_channels,
)
batch_size, _, num_channels = videos_patch.shape
labels = videos_patch[bool_masked_pos].reshape(batch_size, -1, num_channels)
loss_fct = MSELoss()
loss = loss_fct(logits, labels)
if not return_dict:
output = (logits,) + outputs[1:]
return ((loss,) + output) if loss is not None else output
return VideoMAEForPreTrainingOutput(
loss=loss,
logits=logits,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
@auto_docstring(
custom_intro="""
VideoMAE Model transformer with a video classification head on top (a linear layer on top of the average pooled hidden
states of all tokens) e.g. for ImageNet.
"""
)
class VideoMAEForVideoClassification(VideoMAEPreTrainedModel):
def __init__(self, config):
super().__init__(config)
self.num_labels = config.num_labels
self.videomae = VideoMAEModel(config)
# Classifier head
self.fc_norm = nn.LayerNorm(config.hidden_size) if config.use_mean_pooling else None
self.classifier = nn.Linear(config.hidden_size, config.num_labels) if config.num_labels > 0 else nn.Identity()
# Initialize weights and apply final processing
self.post_init()
@auto_docstring
def forward(
self,
pixel_values: Optional[torch.Tensor] = None,
head_mask: Optional[torch.Tensor] = None,
labels: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
) -> Union[tuple, ImageClassifierOutput]:
r"""
labels (`torch.LongTensor` of shape `(batch_size,)`, *optional*):
Labels for computing the image classification/regression loss. Indices should be in `[0, ...,
config.num_labels - 1]`. If `config.num_labels == 1` a regression loss is computed (Mean-Square loss), If
`config.num_labels > 1` a classification loss is computed (Cross-Entropy).
Examples:
```python
>>> import av
>>> import torch
>>> import numpy as np
>>> from transformers import AutoImageProcessor, VideoMAEForVideoClassification
>>> from huggingface_hub import hf_hub_download
>>> np.random.seed(0)
>>> 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
>>> # video clip consists of 300 frames (10 seconds at 30 FPS)
>>> file_path = hf_hub_download(
... repo_id="nielsr/video-demo", filename="eating_spaghetti.mp4", repo_type="dataset"
... )
>>> container = av.open(file_path)
>>> # sample 16 frames
>>> indices = sample_frame_indices(clip_len=16, frame_sample_rate=1, seg_len=container.streams.video[0].frames)
>>> video = read_video_pyav(container, indices)
>>> image_processor = AutoImageProcessor.from_pretrained("MCG-NJU/videomae-base-finetuned-kinetics")
>>> model = VideoMAEForVideoClassification.from_pretrained("MCG-NJU/videomae-base-finetuned-kinetics")
>>> inputs = image_processor(list(video), return_tensors="pt")
>>> with torch.no_grad():
... outputs = model(**inputs)
... logits = outputs.logits
>>> # model predicts one of the 400 Kinetics-400 classes
>>> predicted_label = logits.argmax(-1).item()
>>> print(model.config.id2label[predicted_label])
eating spaghetti
```"""
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
outputs = self.videomae(
pixel_values,
head_mask=head_mask,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
sequence_output = outputs[0]
if self.fc_norm is not None:
sequence_output = self.fc_norm(sequence_output.mean(1))
else:
sequence_output = sequence_output[:, 0]
logits = self.classifier(sequence_output)
loss = None
if labels is not None:
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)
if not return_dict:
output = (logits,) + outputs[1:]
return ((loss,) + output) if loss is not None else output
return ImageClassifierOutput(
loss=loss,
logits=logits,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
__all__ = ["VideoMAEForPreTraining", "VideoMAEModel", "VideoMAEPreTrainedModel", "VideoMAEForVideoClassification"]