ai-content-maker/.venv/Lib/site-packages/transformers/models/mobilevitv2/modeling_mobilevitv2.py

1031 lines
37 KiB
Python

# coding=utf-8
# Copyright 2023 Apple Inc. 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.
#
# Original license: https://github.com/apple/ml-cvnets/blob/main/LICENSE
""" PyTorch MobileViTV2 model."""
from typing import Optional, Tuple, Union
import torch
import torch.utils.checkpoint
from torch import nn
from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss
from ...activations import ACT2FN
from ...modeling_outputs import (
BaseModelOutputWithNoAttention,
BaseModelOutputWithPoolingAndNoAttention,
ImageClassifierOutputWithNoAttention,
SemanticSegmenterOutput,
)
from ...modeling_utils import PreTrainedModel
from ...utils import (
add_code_sample_docstrings,
add_start_docstrings,
add_start_docstrings_to_model_forward,
logging,
replace_return_docstrings,
)
from .configuration_mobilevitv2 import MobileViTV2Config
logger = logging.get_logger(__name__)
# General docstring
_CONFIG_FOR_DOC = "MobileViTV2Config"
# Base docstring
_CHECKPOINT_FOR_DOC = "apple/mobilevitv2-1.0-imagenet1k-256"
_EXPECTED_OUTPUT_SHAPE = [1, 512, 8, 8]
# Image classification docstring
_IMAGE_CLASS_CHECKPOINT = "apple/mobilevitv2-1.0-imagenet1k-256"
_IMAGE_CLASS_EXPECTED_OUTPUT = "tabby, tabby cat"
from ..deprecated._archive_maps import MOBILEVITV2_PRETRAINED_MODEL_ARCHIVE_LIST # noqa: F401, E402
# Copied from transformers.models.mobilevit.modeling_mobilevit.make_divisible
def make_divisible(value: int, divisor: int = 8, min_value: Optional[int] = None) -> int:
"""
Ensure that all layers have a channel count that is divisible by `divisor`. This function is taken from the
original TensorFlow repo. It can be seen here:
https://github.com/tensorflow/models/blob/master/research/slim/nets/mobilenet/mobilenet.py
"""
if min_value is None:
min_value = divisor
new_value = max(min_value, int(value + divisor / 2) // divisor * divisor)
# Make sure that round down does not go down by more than 10%.
if new_value < 0.9 * value:
new_value += divisor
return int(new_value)
def clip(value: float, min_val: float = float("-inf"), max_val: float = float("inf")) -> float:
return max(min_val, min(max_val, value))
# Copied from transformers.models.mobilevit.modeling_mobilevit.MobileViTConvLayer with MobileViT->MobileViTV2
class MobileViTV2ConvLayer(nn.Module):
def __init__(
self,
config: MobileViTV2Config,
in_channels: int,
out_channels: int,
kernel_size: int,
stride: int = 1,
groups: int = 1,
bias: bool = False,
dilation: int = 1,
use_normalization: bool = True,
use_activation: Union[bool, str] = True,
) -> None:
super().__init__()
padding = int((kernel_size - 1) / 2) * dilation
if in_channels % groups != 0:
raise ValueError(f"Input channels ({in_channels}) are not divisible by {groups} groups.")
if out_channels % groups != 0:
raise ValueError(f"Output channels ({out_channels}) are not divisible by {groups} groups.")
self.convolution = nn.Conv2d(
in_channels=in_channels,
out_channels=out_channels,
kernel_size=kernel_size,
stride=stride,
padding=padding,
dilation=dilation,
groups=groups,
bias=bias,
padding_mode="zeros",
)
if use_normalization:
self.normalization = nn.BatchNorm2d(
num_features=out_channels,
eps=1e-5,
momentum=0.1,
affine=True,
track_running_stats=True,
)
else:
self.normalization = None
if use_activation:
if isinstance(use_activation, str):
self.activation = ACT2FN[use_activation]
elif isinstance(config.hidden_act, str):
self.activation = ACT2FN[config.hidden_act]
else:
self.activation = config.hidden_act
else:
self.activation = None
def forward(self, features: torch.Tensor) -> torch.Tensor:
features = self.convolution(features)
if self.normalization is not None:
features = self.normalization(features)
if self.activation is not None:
features = self.activation(features)
return features
# Copied from transformers.models.mobilevit.modeling_mobilevit.MobileViTInvertedResidual with MobileViT->MobileViTV2
class MobileViTV2InvertedResidual(nn.Module):
"""
Inverted residual block (MobileNetv2): https://arxiv.org/abs/1801.04381
"""
def __init__(
self, config: MobileViTV2Config, in_channels: int, out_channels: int, stride: int, dilation: int = 1
) -> None:
super().__init__()
expanded_channels = make_divisible(int(round(in_channels * config.expand_ratio)), 8)
if stride not in [1, 2]:
raise ValueError(f"Invalid stride {stride}.")
self.use_residual = (stride == 1) and (in_channels == out_channels)
self.expand_1x1 = MobileViTV2ConvLayer(
config, in_channels=in_channels, out_channels=expanded_channels, kernel_size=1
)
self.conv_3x3 = MobileViTV2ConvLayer(
config,
in_channels=expanded_channels,
out_channels=expanded_channels,
kernel_size=3,
stride=stride,
groups=expanded_channels,
dilation=dilation,
)
self.reduce_1x1 = MobileViTV2ConvLayer(
config,
in_channels=expanded_channels,
out_channels=out_channels,
kernel_size=1,
use_activation=False,
)
def forward(self, features: torch.Tensor) -> torch.Tensor:
residual = features
features = self.expand_1x1(features)
features = self.conv_3x3(features)
features = self.reduce_1x1(features)
return residual + features if self.use_residual else features
# Copied from transformers.models.mobilevit.modeling_mobilevit.MobileViTMobileNetLayer with MobileViT->MobileViTV2
class MobileViTV2MobileNetLayer(nn.Module):
def __init__(
self, config: MobileViTV2Config, in_channels: int, out_channels: int, stride: int = 1, num_stages: int = 1
) -> None:
super().__init__()
self.layer = nn.ModuleList()
for i in range(num_stages):
layer = MobileViTV2InvertedResidual(
config,
in_channels=in_channels,
out_channels=out_channels,
stride=stride if i == 0 else 1,
)
self.layer.append(layer)
in_channels = out_channels
def forward(self, features: torch.Tensor) -> torch.Tensor:
for layer_module in self.layer:
features = layer_module(features)
return features
class MobileViTV2LinearSelfAttention(nn.Module):
"""
This layer applies a self-attention with linear complexity, as described in MobileViTV2 paper:
https://arxiv.org/abs/2206.02680
Args:
config (`MobileVitv2Config`):
Model configuration object
embed_dim (`int`):
`input_channels` from an expected input of size :math:`(batch_size, input_channels, height, width)`
"""
def __init__(self, config: MobileViTV2Config, embed_dim: int) -> None:
super().__init__()
self.qkv_proj = MobileViTV2ConvLayer(
config=config,
in_channels=embed_dim,
out_channels=1 + (2 * embed_dim),
bias=True,
kernel_size=1,
use_normalization=False,
use_activation=False,
)
self.attn_dropout = nn.Dropout(p=config.attn_dropout)
self.out_proj = MobileViTV2ConvLayer(
config=config,
in_channels=embed_dim,
out_channels=embed_dim,
bias=True,
kernel_size=1,
use_normalization=False,
use_activation=False,
)
self.embed_dim = embed_dim
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
# (batch_size, embed_dim, num_pixels_in_patch, num_patches) --> (batch_size, 1+2*embed_dim, num_pixels_in_patch, num_patches)
qkv = self.qkv_proj(hidden_states)
# Project hidden_states into query, key and value
# Query --> [batch_size, 1, num_pixels_in_patch, num_patches]
# value, key --> [batch_size, embed_dim, num_pixels_in_patch, num_patches]
query, key, value = torch.split(qkv, split_size_or_sections=[1, self.embed_dim, self.embed_dim], dim=1)
# apply softmax along num_patches dimension
context_scores = torch.nn.functional.softmax(query, dim=-1)
context_scores = self.attn_dropout(context_scores)
# Compute context vector
# [batch_size, embed_dim, num_pixels_in_patch, num_patches] x [batch_size, 1, num_pixels_in_patch, num_patches] -> [batch_size, embed_dim, num_pixels_in_patch, num_patches]
context_vector = key * context_scores
# [batch_size, embed_dim, num_pixels_in_patch, num_patches] --> [batch_size, embed_dim, num_pixels_in_patch, 1]
context_vector = torch.sum(context_vector, dim=-1, keepdim=True)
# combine context vector with values
# [batch_size, embed_dim, num_pixels_in_patch, num_patches] * [batch_size, embed_dim, num_pixels_in_patch, 1] --> [batch_size, embed_dim, num_pixels_in_patch, num_patches]
out = torch.nn.functional.relu(value) * context_vector.expand_as(value)
out = self.out_proj(out)
return out
class MobileViTV2FFN(nn.Module):
def __init__(
self,
config: MobileViTV2Config,
embed_dim: int,
ffn_latent_dim: int,
ffn_dropout: float = 0.0,
) -> None:
super().__init__()
self.conv1 = MobileViTV2ConvLayer(
config=config,
in_channels=embed_dim,
out_channels=ffn_latent_dim,
kernel_size=1,
stride=1,
bias=True,
use_normalization=False,
use_activation=True,
)
self.dropout1 = nn.Dropout(ffn_dropout)
self.conv2 = MobileViTV2ConvLayer(
config=config,
in_channels=ffn_latent_dim,
out_channels=embed_dim,
kernel_size=1,
stride=1,
bias=True,
use_normalization=False,
use_activation=False,
)
self.dropout2 = nn.Dropout(ffn_dropout)
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
hidden_states = self.conv1(hidden_states)
hidden_states = self.dropout1(hidden_states)
hidden_states = self.conv2(hidden_states)
hidden_states = self.dropout2(hidden_states)
return hidden_states
class MobileViTV2TransformerLayer(nn.Module):
def __init__(
self,
config: MobileViTV2Config,
embed_dim: int,
ffn_latent_dim: int,
dropout: float = 0.0,
) -> None:
super().__init__()
self.layernorm_before = nn.GroupNorm(num_groups=1, num_channels=embed_dim, eps=config.layer_norm_eps)
self.attention = MobileViTV2LinearSelfAttention(config, embed_dim)
self.dropout1 = nn.Dropout(p=dropout)
self.layernorm_after = nn.GroupNorm(num_groups=1, num_channels=embed_dim, eps=config.layer_norm_eps)
self.ffn = MobileViTV2FFN(config, embed_dim, ffn_latent_dim, config.ffn_dropout)
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
layernorm_1_out = self.layernorm_before(hidden_states)
attention_output = self.attention(layernorm_1_out)
hidden_states = attention_output + hidden_states
layer_output = self.layernorm_after(hidden_states)
layer_output = self.ffn(layer_output)
layer_output = layer_output + hidden_states
return layer_output
class MobileViTV2Transformer(nn.Module):
def __init__(self, config: MobileViTV2Config, n_layers: int, d_model: int) -> None:
super().__init__()
ffn_multiplier = config.ffn_multiplier
ffn_dims = [ffn_multiplier * d_model] * n_layers
# ensure that dims are multiple of 16
ffn_dims = [int((d // 16) * 16) for d in ffn_dims]
self.layer = nn.ModuleList()
for block_idx in range(n_layers):
transformer_layer = MobileViTV2TransformerLayer(
config, embed_dim=d_model, ffn_latent_dim=ffn_dims[block_idx]
)
self.layer.append(transformer_layer)
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
for layer_module in self.layer:
hidden_states = layer_module(hidden_states)
return hidden_states
class MobileViTV2Layer(nn.Module):
"""
MobileViTV2 layer: https://arxiv.org/abs/2206.02680
"""
def __init__(
self,
config: MobileViTV2Config,
in_channels: int,
out_channels: int,
attn_unit_dim: int,
n_attn_blocks: int = 2,
dilation: int = 1,
stride: int = 2,
) -> None:
super().__init__()
self.patch_width = config.patch_size
self.patch_height = config.patch_size
cnn_out_dim = attn_unit_dim
if stride == 2:
self.downsampling_layer = MobileViTV2InvertedResidual(
config,
in_channels=in_channels,
out_channels=out_channels,
stride=stride if dilation == 1 else 1,
dilation=dilation // 2 if dilation > 1 else 1,
)
in_channels = out_channels
else:
self.downsampling_layer = None
# Local representations
self.conv_kxk = MobileViTV2ConvLayer(
config,
in_channels=in_channels,
out_channels=in_channels,
kernel_size=config.conv_kernel_size,
groups=in_channels,
)
self.conv_1x1 = MobileViTV2ConvLayer(
config,
in_channels=in_channels,
out_channels=cnn_out_dim,
kernel_size=1,
use_normalization=False,
use_activation=False,
)
# Global representations
self.transformer = MobileViTV2Transformer(config, d_model=attn_unit_dim, n_layers=n_attn_blocks)
# self.layernorm = MobileViTV2LayerNorm2D(attn_unit_dim, eps=config.layer_norm_eps)
self.layernorm = nn.GroupNorm(num_groups=1, num_channels=attn_unit_dim, eps=config.layer_norm_eps)
# Fusion
self.conv_projection = MobileViTV2ConvLayer(
config,
in_channels=cnn_out_dim,
out_channels=in_channels,
kernel_size=1,
use_normalization=True,
use_activation=False,
)
def unfolding(self, feature_map: torch.Tensor) -> Tuple[torch.Tensor, Tuple[int, int]]:
batch_size, in_channels, img_height, img_width = feature_map.shape
patches = nn.functional.unfold(
feature_map,
kernel_size=(self.patch_height, self.patch_width),
stride=(self.patch_height, self.patch_width),
)
patches = patches.reshape(batch_size, in_channels, self.patch_height * self.patch_width, -1)
return patches, (img_height, img_width)
def folding(self, patches: torch.Tensor, output_size: Tuple[int, int]) -> torch.Tensor:
batch_size, in_dim, patch_size, n_patches = patches.shape
patches = patches.reshape(batch_size, in_dim * patch_size, n_patches)
feature_map = nn.functional.fold(
patches,
output_size=output_size,
kernel_size=(self.patch_height, self.patch_width),
stride=(self.patch_height, self.patch_width),
)
return feature_map
def forward(self, features: torch.Tensor) -> torch.Tensor:
# reduce spatial dimensions if needed
if self.downsampling_layer:
features = self.downsampling_layer(features)
# local representation
features = self.conv_kxk(features)
features = self.conv_1x1(features)
# convert feature map to patches
patches, output_size = self.unfolding(features)
# learn global representations
patches = self.transformer(patches)
patches = self.layernorm(patches)
# convert patches back to feature maps
# [batch_size, patch_height, patch_width, input_dim] --> [batch_size, input_dim, patch_height, patch_width]
features = self.folding(patches, output_size)
features = self.conv_projection(features)
return features
class MobileViTV2Encoder(nn.Module):
def __init__(self, config: MobileViTV2Config) -> None:
super().__init__()
self.config = config
self.layer = nn.ModuleList()
self.gradient_checkpointing = False
# segmentation architectures like DeepLab and PSPNet modify the strides
# of the classification backbones
dilate_layer_4 = dilate_layer_5 = False
if config.output_stride == 8:
dilate_layer_4 = True
dilate_layer_5 = True
elif config.output_stride == 16:
dilate_layer_5 = True
dilation = 1
layer_0_dim = make_divisible(
clip(value=32 * config.width_multiplier, min_val=16, max_val=64), divisor=8, min_value=16
)
layer_1_dim = make_divisible(64 * config.width_multiplier, divisor=16)
layer_2_dim = make_divisible(128 * config.width_multiplier, divisor=8)
layer_3_dim = make_divisible(256 * config.width_multiplier, divisor=8)
layer_4_dim = make_divisible(384 * config.width_multiplier, divisor=8)
layer_5_dim = make_divisible(512 * config.width_multiplier, divisor=8)
layer_1 = MobileViTV2MobileNetLayer(
config,
in_channels=layer_0_dim,
out_channels=layer_1_dim,
stride=1,
num_stages=1,
)
self.layer.append(layer_1)
layer_2 = MobileViTV2MobileNetLayer(
config,
in_channels=layer_1_dim,
out_channels=layer_2_dim,
stride=2,
num_stages=2,
)
self.layer.append(layer_2)
layer_3 = MobileViTV2Layer(
config,
in_channels=layer_2_dim,
out_channels=layer_3_dim,
attn_unit_dim=make_divisible(config.base_attn_unit_dims[0] * config.width_multiplier, divisor=8),
n_attn_blocks=config.n_attn_blocks[0],
)
self.layer.append(layer_3)
if dilate_layer_4:
dilation *= 2
layer_4 = MobileViTV2Layer(
config,
in_channels=layer_3_dim,
out_channels=layer_4_dim,
attn_unit_dim=make_divisible(config.base_attn_unit_dims[1] * config.width_multiplier, divisor=8),
n_attn_blocks=config.n_attn_blocks[1],
dilation=dilation,
)
self.layer.append(layer_4)
if dilate_layer_5:
dilation *= 2
layer_5 = MobileViTV2Layer(
config,
in_channels=layer_4_dim,
out_channels=layer_5_dim,
attn_unit_dim=make_divisible(config.base_attn_unit_dims[2] * config.width_multiplier, divisor=8),
n_attn_blocks=config.n_attn_blocks[2],
dilation=dilation,
)
self.layer.append(layer_5)
def forward(
self,
hidden_states: torch.Tensor,
output_hidden_states: bool = False,
return_dict: bool = True,
) -> Union[tuple, BaseModelOutputWithNoAttention]:
all_hidden_states = () if output_hidden_states else None
for i, layer_module in enumerate(self.layer):
if self.gradient_checkpointing and self.training:
hidden_states = self._gradient_checkpointing_func(
layer_module.__call__,
hidden_states,
)
else:
hidden_states = layer_module(hidden_states)
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] if v is not None)
return BaseModelOutputWithNoAttention(last_hidden_state=hidden_states, hidden_states=all_hidden_states)
# Copied from transformers.models.mobilevit.modeling_mobilevit.MobileViTPreTrainedModel with MobileViT->MobileViTV2,mobilevit->mobilevitv2
class MobileViTV2PreTrainedModel(PreTrainedModel):
"""
An abstract class to handle weights initialization and a simple interface for downloading and loading pretrained
models.
"""
config_class = MobileViTV2Config
base_model_prefix = "mobilevitv2"
main_input_name = "pixel_values"
supports_gradient_checkpointing = True
def _init_weights(self, module: Union[nn.Linear, nn.Conv2d, nn.LayerNorm]) -> None:
"""Initialize the weights"""
if isinstance(module, (nn.Linear, nn.Conv2d)):
# 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)
MOBILEVITV2_START_DOCSTRING = r"""
This model is a PyTorch [torch.nn.Module](https://pytorch.org/docs/stable/nn.html#torch.nn.Module) subclass. Use it
as a regular PyTorch Module and refer to the PyTorch documentation for all matter related to general usage and
behavior.
Parameters:
config ([`MobileViTV2Config`]): Model configuration class with all the parameters of the model.
Initializing with a config file does not load the weights associated with the model, only the
configuration. Check out the [`~PreTrainedModel.from_pretrained`] method to load the model weights.
"""
MOBILEVITV2_INPUTS_DOCSTRING = r"""
Args:
pixel_values (`torch.FloatTensor` of shape `(batch_size, num_channels, height, width)`):
Pixel values. Pixel values can be obtained using [`AutoImageProcessor`]. See
[`MobileViTImageProcessor.__call__`] for details.
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.
"""
@add_start_docstrings(
"The bare MobileViTV2 model outputting raw hidden-states without any specific head on top.",
MOBILEVITV2_START_DOCSTRING,
)
class MobileViTV2Model(MobileViTV2PreTrainedModel):
def __init__(self, config: MobileViTV2Config, expand_output: bool = True):
super().__init__(config)
self.config = config
self.expand_output = expand_output
layer_0_dim = make_divisible(
clip(value=32 * config.width_multiplier, min_val=16, max_val=64), divisor=8, min_value=16
)
self.conv_stem = MobileViTV2ConvLayer(
config,
in_channels=config.num_channels,
out_channels=layer_0_dim,
kernel_size=3,
stride=2,
use_normalization=True,
use_activation=True,
)
self.encoder = MobileViTV2Encoder(config)
# Initialize weights and apply final processing
self.post_init()
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_index, heads in heads_to_prune.items():
mobilevitv2_layer = self.encoder.layer[layer_index]
if isinstance(mobilevitv2_layer, MobileViTV2Layer):
for transformer_layer in mobilevitv2_layer.transformer.layer:
transformer_layer.attention.prune_heads(heads)
@add_start_docstrings_to_model_forward(MOBILEVITV2_INPUTS_DOCSTRING)
@add_code_sample_docstrings(
checkpoint=_CHECKPOINT_FOR_DOC,
output_type=BaseModelOutputWithPoolingAndNoAttention,
config_class=_CONFIG_FOR_DOC,
modality="vision",
expected_output=_EXPECTED_OUTPUT_SHAPE,
)
def forward(
self,
pixel_values: Optional[torch.Tensor] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
) -> Union[tuple, BaseModelOutputWithPoolingAndNoAttention]:
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")
embedding_output = self.conv_stem(pixel_values)
encoder_outputs = self.encoder(
embedding_output,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
if self.expand_output:
last_hidden_state = encoder_outputs[0]
# global average pooling: (batch_size, channels, height, width) -> (batch_size, channels)
pooled_output = torch.mean(last_hidden_state, dim=[-2, -1], keepdim=False)
else:
last_hidden_state = encoder_outputs[0]
pooled_output = None
if not return_dict:
output = (last_hidden_state, pooled_output) if pooled_output is not None else (last_hidden_state,)
return output + encoder_outputs[1:]
return BaseModelOutputWithPoolingAndNoAttention(
last_hidden_state=last_hidden_state,
pooler_output=pooled_output,
hidden_states=encoder_outputs.hidden_states,
)
@add_start_docstrings(
"""
MobileViTV2 model with an image classification head on top (a linear layer on top of the pooled features), e.g. for
ImageNet.
""",
MOBILEVITV2_START_DOCSTRING,
)
class MobileViTV2ForImageClassification(MobileViTV2PreTrainedModel):
def __init__(self, config: MobileViTV2Config) -> None:
super().__init__(config)
self.num_labels = config.num_labels
self.mobilevitv2 = MobileViTV2Model(config)
out_channels = make_divisible(512 * config.width_multiplier, divisor=8) # layer 5 output dimension
# Classifier head
self.classifier = (
nn.Linear(in_features=out_channels, out_features=config.num_labels)
if config.num_labels > 0
else nn.Identity()
)
# Initialize weights and apply final processing
self.post_init()
@add_start_docstrings_to_model_forward(MOBILEVITV2_INPUTS_DOCSTRING)
@add_code_sample_docstrings(
checkpoint=_IMAGE_CLASS_CHECKPOINT,
output_type=ImageClassifierOutputWithNoAttention,
config_class=_CONFIG_FOR_DOC,
expected_output=_IMAGE_CLASS_EXPECTED_OUTPUT,
)
def forward(
self,
pixel_values: Optional[torch.Tensor] = None,
output_hidden_states: Optional[bool] = None,
labels: Optional[torch.Tensor] = None,
return_dict: Optional[bool] = None,
) -> Union[tuple, ImageClassifierOutputWithNoAttention]:
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).
"""
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
outputs = self.mobilevitv2(pixel_values, output_hidden_states=output_hidden_states, return_dict=return_dict)
pooled_output = outputs.pooler_output if return_dict else outputs[1]
logits = self.classifier(pooled_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[2:]
return ((loss,) + output) if loss is not None else output
return ImageClassifierOutputWithNoAttention(
loss=loss,
logits=logits,
hidden_states=outputs.hidden_states,
)
# Copied from transformers.models.mobilevit.modeling_mobilevit.MobileViTASPPPooling with MobileViT->MobileViTV2
class MobileViTV2ASPPPooling(nn.Module):
def __init__(self, config: MobileViTV2Config, in_channels: int, out_channels: int) -> None:
super().__init__()
self.global_pool = nn.AdaptiveAvgPool2d(output_size=1)
self.conv_1x1 = MobileViTV2ConvLayer(
config,
in_channels=in_channels,
out_channels=out_channels,
kernel_size=1,
stride=1,
use_normalization=True,
use_activation="relu",
)
def forward(self, features: torch.Tensor) -> torch.Tensor:
spatial_size = features.shape[-2:]
features = self.global_pool(features)
features = self.conv_1x1(features)
features = nn.functional.interpolate(features, size=spatial_size, mode="bilinear", align_corners=False)
return features
class MobileViTV2ASPP(nn.Module):
"""
ASPP module defined in DeepLab papers: https://arxiv.org/abs/1606.00915, https://arxiv.org/abs/1706.05587
"""
def __init__(self, config: MobileViTV2Config) -> None:
super().__init__()
encoder_out_channels = make_divisible(512 * config.width_multiplier, divisor=8) # layer 5 output dimension
in_channels = encoder_out_channels
out_channels = config.aspp_out_channels
if len(config.atrous_rates) != 3:
raise ValueError("Expected 3 values for atrous_rates")
self.convs = nn.ModuleList()
in_projection = MobileViTV2ConvLayer(
config,
in_channels=in_channels,
out_channels=out_channels,
kernel_size=1,
use_activation="relu",
)
self.convs.append(in_projection)
self.convs.extend(
[
MobileViTV2ConvLayer(
config,
in_channels=in_channels,
out_channels=out_channels,
kernel_size=3,
dilation=rate,
use_activation="relu",
)
for rate in config.atrous_rates
]
)
pool_layer = MobileViTV2ASPPPooling(config, in_channels, out_channels)
self.convs.append(pool_layer)
self.project = MobileViTV2ConvLayer(
config, in_channels=5 * out_channels, out_channels=out_channels, kernel_size=1, use_activation="relu"
)
self.dropout = nn.Dropout(p=config.aspp_dropout_prob)
def forward(self, features: torch.Tensor) -> torch.Tensor:
pyramid = []
for conv in self.convs:
pyramid.append(conv(features))
pyramid = torch.cat(pyramid, dim=1)
pooled_features = self.project(pyramid)
pooled_features = self.dropout(pooled_features)
return pooled_features
# Copied from transformers.models.mobilevit.modeling_mobilevit.MobileViTDeepLabV3 with MobileViT->MobileViTV2
class MobileViTV2DeepLabV3(nn.Module):
"""
DeepLabv3 architecture: https://arxiv.org/abs/1706.05587
"""
def __init__(self, config: MobileViTV2Config) -> None:
super().__init__()
self.aspp = MobileViTV2ASPP(config)
self.dropout = nn.Dropout2d(config.classifier_dropout_prob)
self.classifier = MobileViTV2ConvLayer(
config,
in_channels=config.aspp_out_channels,
out_channels=config.num_labels,
kernel_size=1,
use_normalization=False,
use_activation=False,
bias=True,
)
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
features = self.aspp(hidden_states[-1])
features = self.dropout(features)
features = self.classifier(features)
return features
@add_start_docstrings(
"""
MobileViTV2 model with a semantic segmentation head on top, e.g. for Pascal VOC.
""",
MOBILEVITV2_START_DOCSTRING,
)
class MobileViTV2ForSemanticSegmentation(MobileViTV2PreTrainedModel):
def __init__(self, config: MobileViTV2Config) -> None:
super().__init__(config)
self.num_labels = config.num_labels
self.mobilevitv2 = MobileViTV2Model(config, expand_output=False)
self.segmentation_head = MobileViTV2DeepLabV3(config)
# Initialize weights and apply final processing
self.post_init()
@add_start_docstrings_to_model_forward(MOBILEVITV2_INPUTS_DOCSTRING)
@replace_return_docstrings(output_type=SemanticSegmenterOutput, config_class=_CONFIG_FOR_DOC)
def forward(
self,
pixel_values: Optional[torch.Tensor] = None,
labels: Optional[torch.Tensor] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
) -> Union[tuple, SemanticSegmenterOutput]:
r"""
labels (`torch.LongTensor` of shape `(batch_size, height, width)`, *optional*):
Ground truth semantic segmentation maps for computing the loss. Indices should be in `[0, ...,
config.num_labels - 1]`. If `config.num_labels > 1`, a classification loss is computed (Cross-Entropy).
Returns:
Examples:
```python
>>> import requests
>>> import torch
>>> from PIL import Image
>>> from transformers import AutoImageProcessor, MobileViTV2ForSemanticSegmentation
>>> url = "http://images.cocodataset.org/val2017/000000039769.jpg"
>>> image = Image.open(requests.get(url, stream=True).raw)
>>> image_processor = AutoImageProcessor.from_pretrained("apple/mobilevitv2-1.0-imagenet1k-256")
>>> model = MobileViTV2ForSemanticSegmentation.from_pretrained("apple/mobilevitv2-1.0-imagenet1k-256")
>>> inputs = image_processor(images=image, return_tensors="pt")
>>> with torch.no_grad():
... outputs = model(**inputs)
>>> # logits are of shape (batch_size, num_labels, height, width)
>>> logits = outputs.logits
```"""
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
outputs = self.mobilevitv2(
pixel_values,
output_hidden_states=True, # we need the intermediate hidden states
return_dict=return_dict,
)
encoder_hidden_states = outputs.hidden_states if return_dict else outputs[1]
logits = self.segmentation_head(encoder_hidden_states)
loss = None
if labels is not None:
if self.config.num_labels == 1:
raise ValueError("The number of labels should be greater than one")
else:
# upsample logits to the images' original size
upsampled_logits = nn.functional.interpolate(
logits, size=labels.shape[-2:], mode="bilinear", align_corners=False
)
loss_fct = CrossEntropyLoss(ignore_index=self.config.semantic_loss_ignore_index)
loss = loss_fct(upsampled_logits, labels)
if not return_dict:
if output_hidden_states:
output = (logits,) + outputs[1:]
else:
output = (logits,) + outputs[2:]
return ((loss,) + output) if loss is not None else output
return SemanticSegmenterOutput(
loss=loss,
logits=logits,
hidden_states=outputs.hidden_states if output_hidden_states else None,
attentions=None,
)