第一次提交Yolo项目
This commit is contained in:
6
mobileclip/modules/common/__init__.py
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6
mobileclip/modules/common/__init__.py
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# Ultralytics 🚀 AGPL-3.0 License - https://ultralytics.com/license
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#
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# For licensing see accompanying LICENSE file.
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# Copyright (C) 2024 Apple Inc. All rights reserved.
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#
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330
mobileclip/modules/common/mobileone.py
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330
mobileclip/modules/common/mobileone.py
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# Ultralytics 🚀 AGPL-3.0 License - https://ultralytics.com/license
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# For licensing see accompanying LICENSE file.
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# Copyright (C) 2024 Apple Inc. All Rights Reserved.
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from __future__ import annotations
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import copy
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import torch
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import torch.nn as nn
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import torch.nn.functional as F
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__all__ = ["MobileOneBlock", "reparameterize_model"]
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class SEBlock(nn.Module):
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"""Squeeze and Excite module.
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Pytorch implementation of `Squeeze-and-Excitation Networks` - https://arxiv.org/pdf/1709.01507.pdf
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"""
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def __init__(self, in_channels: int, rd_ratio: float = 0.0625) -> None:
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"""Construct a Squeeze and Excite Module.
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Args:
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in_channels: Number of input channels.
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rd_ratio: Input channel reduction ratio.
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"""
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super().__init__()
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self.reduce = nn.Conv2d(
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in_channels=in_channels,
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out_channels=int(in_channels * rd_ratio),
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kernel_size=1,
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stride=1,
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bias=True,
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)
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self.expand = nn.Conv2d(
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in_channels=int(in_channels * rd_ratio),
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out_channels=in_channels,
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kernel_size=1,
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stride=1,
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bias=True,
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)
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def forward(self, inputs: torch.Tensor) -> torch.Tensor:
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"""Apply forward pass."""
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_b, c, h, w = inputs.size()
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x = F.avg_pool2d(inputs, kernel_size=[h, w])
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x = self.reduce(x)
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x = F.relu(x)
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x = self.expand(x)
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x = torch.sigmoid(x)
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x = x.view(-1, c, 1, 1)
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return inputs * x
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class MobileOneBlock(nn.Module):
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"""MobileOne building block.
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This block has a multi-branched architecture at train-time and plain-CNN style architecture at inference time For
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more details, please refer to our paper: `An Improved One millisecond Mobile Backbone` -
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https://arxiv.org/pdf/2206.04040.pdf
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"""
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def __init__(
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self,
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in_channels: int,
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out_channels: int,
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kernel_size: int,
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stride: int = 1,
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padding: int = 0,
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dilation: int = 1,
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groups: int = 1,
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inference_mode: bool = False,
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use_se: bool = False,
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use_act: bool = True,
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use_scale_branch: bool = True,
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num_conv_branches: int = 1,
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activation: nn.Module = nn.GELU(),
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) -> None:
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"""Construct a MobileOneBlock module.
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Args:
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in_channels: Number of channels in the input.
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out_channels: Number of channels produced by the block.
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kernel_size: Size of the convolution kernel.
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stride: Stride size.
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padding: Zero-padding size.
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dilation: Kernel dilation factor.
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groups: Group number.
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inference_mode: If True, instantiates model in inference mode.
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use_se: Whether to use SE-ReLU activations.
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use_act: Whether to use activation. Default: ``True``
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use_scale_branch: Whether to use scale branch. Default: ``True``
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num_conv_branches: Number of linear conv branches.
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"""
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super().__init__()
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self.inference_mode = inference_mode
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self.groups = groups
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self.stride = stride
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self.padding = padding
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self.dilation = dilation
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self.kernel_size = kernel_size
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self.in_channels = in_channels
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self.out_channels = out_channels
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self.num_conv_branches = num_conv_branches
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# Check if SE-ReLU is requested
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if use_se:
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self.se = SEBlock(out_channels)
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else:
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self.se = nn.Identity()
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if use_act:
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self.activation = activation
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else:
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self.activation = nn.Identity()
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if inference_mode:
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self.reparam_conv = nn.Conv2d(
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in_channels=in_channels,
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out_channels=out_channels,
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kernel_size=kernel_size,
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stride=stride,
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padding=padding,
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dilation=dilation,
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groups=groups,
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bias=True,
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)
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else:
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# Re-parameterizable skip connection
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self.rbr_skip = (
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nn.BatchNorm2d(num_features=in_channels) if out_channels == in_channels and stride == 1 else None
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)
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# Re-parameterizable conv branches
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if num_conv_branches > 0:
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rbr_conv = list()
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for _ in range(self.num_conv_branches):
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rbr_conv.append(self._conv_bn(kernel_size=kernel_size, padding=padding))
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self.rbr_conv = nn.ModuleList(rbr_conv)
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else:
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self.rbr_conv = None
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# Re-parameterizable scale branch
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self.rbr_scale = None
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if not isinstance(kernel_size, int):
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kernel_size = kernel_size[0]
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if (kernel_size > 1) and use_scale_branch:
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self.rbr_scale = self._conv_bn(kernel_size=1, padding=0)
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def forward(self, x: torch.Tensor) -> torch.Tensor:
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"""Apply forward pass."""
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# Inference mode forward pass.
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if self.inference_mode:
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return self.activation(self.se(self.reparam_conv(x)))
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# Multi-branched train-time forward pass.
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# Skip branch output
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identity_out = 0
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if self.rbr_skip is not None:
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identity_out = self.rbr_skip(x)
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# Scale branch output
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scale_out = 0
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if self.rbr_scale is not None:
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scale_out = self.rbr_scale(x)
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# Other branches
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out = scale_out + identity_out
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if self.rbr_conv is not None:
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for ix in range(self.num_conv_branches):
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out += self.rbr_conv[ix](x)
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return self.activation(self.se(out))
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def reparameterize(self):
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"""Following works like `RepVGG: Making VGG-style ConvNets Great Again` - https://arxiv.org/pdf/2101.03697.pdf.
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We re-parameterize multi-branched architecture used at training time to obtain a plain CNN-like
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structure for inference.
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"""
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if self.inference_mode:
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return
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kernel, bias = self._get_kernel_bias()
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self.reparam_conv = nn.Conv2d(
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in_channels=self.in_channels,
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out_channels=self.out_channels,
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kernel_size=self.kernel_size,
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stride=self.stride,
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padding=self.padding,
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dilation=self.dilation,
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groups=self.groups,
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bias=True,
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)
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self.reparam_conv.weight.data = kernel
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self.reparam_conv.bias.data = bias
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# Delete un-used branches
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for para in self.parameters():
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para.detach_()
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self.__delattr__("rbr_conv")
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self.__delattr__("rbr_scale")
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if hasattr(self, "rbr_skip"):
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self.__delattr__("rbr_skip")
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self.inference_mode = True
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def _get_kernel_bias(self) -> tuple[torch.Tensor, torch.Tensor]:
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"""Method to obtain re-parameterized kernel and bias. Reference:
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https://github.com/DingXiaoH/RepVGG/blob/main/repvgg.py#L83.
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Returns:
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Tuple of (kernel, bias) after fusing branches.
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"""
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# get weights and bias of scale branch
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kernel_scale = 0
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bias_scale = 0
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if self.rbr_scale is not None:
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kernel_scale, bias_scale = self._fuse_bn_tensor(self.rbr_scale)
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# Pad scale branch kernel to match conv branch kernel size.
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pad = self.kernel_size // 2
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kernel_scale = torch.nn.functional.pad(kernel_scale, [pad, pad, pad, pad])
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# get weights and bias of skip branch
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kernel_identity = 0
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bias_identity = 0
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if self.rbr_skip is not None:
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kernel_identity, bias_identity = self._fuse_bn_tensor(self.rbr_skip)
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# get weights and bias of conv branches
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kernel_conv = 0
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bias_conv = 0
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if self.rbr_conv is not None:
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for ix in range(self.num_conv_branches):
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_kernel, _bias = self._fuse_bn_tensor(self.rbr_conv[ix])
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kernel_conv += _kernel
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bias_conv += _bias
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kernel_final = kernel_conv + kernel_scale + kernel_identity
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bias_final = bias_conv + bias_scale + bias_identity
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return kernel_final, bias_final
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def _fuse_bn_tensor(self, branch: nn.Sequential | nn.BatchNorm2d) -> tuple[torch.Tensor, torch.Tensor]:
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"""Method to fuse batchnorm layer with preceeding conv layer. Reference:
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https://github.com/DingXiaoH/RepVGG/blob/main/repvgg.py#L95.
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Args:
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branch: Sequence of ops to be fused.
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Returns:
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Tuple of (kernel, bias) after fusing batchnorm.
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"""
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if isinstance(branch, nn.Sequential):
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kernel = branch.conv.weight
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running_mean = branch.bn.running_mean
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running_var = branch.bn.running_var
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gamma = branch.bn.weight
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beta = branch.bn.bias
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eps = branch.bn.eps
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else:
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assert isinstance(branch, nn.BatchNorm2d)
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if not hasattr(self, "id_tensor"):
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input_dim = self.in_channels // self.groups
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kernel_size = self.kernel_size
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if isinstance(self.kernel_size, int):
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kernel_size = (self.kernel_size, self.kernel_size)
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kernel_value = torch.zeros(
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(self.in_channels, input_dim, kernel_size[0], kernel_size[1]),
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dtype=branch.weight.dtype,
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device=branch.weight.device,
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)
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for i in range(self.in_channels):
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kernel_value[i, i % input_dim, kernel_size[0] // 2, kernel_size[1] // 2] = 1
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self.id_tensor = kernel_value
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kernel = self.id_tensor
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running_mean = branch.running_mean
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running_var = branch.running_var
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gamma = branch.weight
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beta = branch.bias
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eps = branch.eps
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std = (running_var + eps).sqrt()
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t = (gamma / std).reshape(-1, 1, 1, 1)
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return kernel * t, beta - running_mean * gamma / std
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def _conv_bn(self, kernel_size: int, padding: int) -> nn.Sequential:
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"""Helper method to construct conv-batchnorm layers.
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Args:
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kernel_size: Size of the convolution kernel.
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padding: Zero-padding size.
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Returns:
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Conv-BN module.
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"""
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mod_list = nn.Sequential()
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mod_list.add_module(
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"conv",
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nn.Conv2d(
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in_channels=self.in_channels,
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out_channels=self.out_channels,
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kernel_size=kernel_size,
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stride=self.stride,
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padding=padding,
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groups=self.groups,
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bias=False,
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),
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)
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mod_list.add_module("bn", nn.BatchNorm2d(num_features=self.out_channels))
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return mod_list
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def reparameterize_model(model: torch.nn.Module) -> nn.Module:
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"""Method returns a model where a multi-branched structure used in training is re-parameterized into a single branch
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for inference.
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Args:
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model: MobileOne model in train mode.
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Returns:
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MobileOne model in inference mode.
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"""
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# Avoid editing original graph
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model = copy.deepcopy(model)
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for module in model.modules():
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if hasattr(module, "reparameterize"):
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module.reparameterize()
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return model
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410
mobileclip/modules/common/transformer.py
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410
mobileclip/modules/common/transformer.py
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# Ultralytics 🚀 AGPL-3.0 License - https://ultralytics.com/license
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#
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# For licensing see accompanying LICENSE file.
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# Copyright (C) 2024 Apple Inc. All Rights Reserved.
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#
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"""
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Implementation of the following modules is borrowed from ml-cvnets repo:
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https://github.com/apple/ml-cvnets/blob/main/cvnets/layers/multi_head_attention.py
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https://github.com/apple/ml-cvnets/blob/main/cvnets/text_encoders/transformer.py.
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Please see ACKNOWLEDGMENTS for license details.
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"""
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from __future__ import annotations
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import torch
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from torch import Size, Tensor, nn
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from torch.nn import functional as F
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from torchvision.ops import StochasticDepth
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from mobileclip import logger
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class LayerNormFP32(nn.LayerNorm):
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"""Applies `Layer Normalization <https://arxiv.org/abs/1607.06450>`_ over a input tensor with FP32 precision."""
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def __init__(
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self,
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normalized_shape: int | list[int] | Size,
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eps: float | None = 1e-5,
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elementwise_affine: bool | None = True,
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*args,
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**kwargs,
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):
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super().__init__(
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normalized_shape=normalized_shape,
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eps=eps,
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elementwise_affine=elementwise_affine,
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*args,
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**kwargs,
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)
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def forward(self, x: Tensor) -> Tensor:
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# Convert input from dtype X to FP32 and perform normalization operation.
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# This may help with underflow/overflow issues that we typically see with normalization layers
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inp_dtype = x.dtype
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return super().forward(x.to(torch.float32)).to(inp_dtype)
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def get_normalization_layer(norm_type, num_features):
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if norm_type == "layer_norm":
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return nn.LayerNorm(num_features)
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elif norm_type == "layer_norm_fp32":
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return LayerNormFP32(num_features)
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else:
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raise NotImplementedError(f"Option: {norm_type} not supported.")
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class PositionalEmbedding(nn.Module):
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def __init__(
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self,
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num_embeddings: int,
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embedding_dim: int,
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padding_idx: int | None = None,
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is_learnable: bool | None = False,
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interpolation_mode: str | None = "bilinear",
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*args,
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**kwargs,
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):
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super().__init__()
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# Add other pos embedding here and logic to choose between them
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module = LearnablePositionalEmbedding
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self.pos_embed = module(
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num_embeddings=num_embeddings,
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embedding_dim=embedding_dim,
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padding_idx=padding_idx,
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interpolation_mode=interpolation_mode,
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*args,
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**kwargs,
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)
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def forward(self, seq_len: int, *args, **kwargs) -> Tensor:
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return self.pos_embed(seq_len, *args, **kwargs)
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def __repr__(self):
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return self.pos_embed.__repr__()
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class LearnablePositionalEmbedding(nn.Module):
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"""Learnable Positional embedding."""
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def __init__(
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self,
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num_embeddings: int,
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embedding_dim: int,
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padding_idx: int | None = None,
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interpolation_mode: str | None = "bilinear",
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*args,
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**kwargs,
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):
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super().__init__()
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self.pos_embed = nn.Parameter(torch.empty(1, 1, num_embeddings, embedding_dim))
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self.embedding_dim = embedding_dim
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self.num_embeddings = num_embeddings
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self.padding_idx = padding_idx
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self.interpolation_mode = interpolation_mode
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self.reset_parameters()
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def reset_parameters(self) -> None:
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nn.init.trunc_normal_(self.pos_embed, mean=0, std=self.embedding_dim**-0.5)
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if self.padding_idx is not None:
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with torch.no_grad():
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self.pos_embed[:, :, self.padding_idx, ...] = 0.0
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def forward(self, seq_len: int, *args, **kwargs) -> Tensor:
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# scale pos embedding
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pos_embed = self.pos_embed
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if self.padding_idx is not None:
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with torch.no_grad():
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pos_embed[:, :, self.padding_idx, ...] = 0.0
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if seq_len != self.num_embeddings:
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pos_embed = F.interpolate(
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pos_embed,
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size=(seq_len, self.embedding_dim),
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mode=self.interpolation_mode,
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)
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# Input is of the form [Batch, Seq_len, Embedding_dim]
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return pos_embed.reshape(1, seq_len, self.embedding_dim)
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def __repr__(self):
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return f"{self.__class__.__name__}(num_embeddings={self.num_embeddings}, embedding_dim={self.embedding_dim}, padding_idx={self.padding_idx})"
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class MultiHeadAttention(nn.Module):
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"""This layer applies a multi-head self- or cross-attention as described in `Attention is all you need
|
||||
<https://arxiv.org/abs/1706.03762>`_ paper.
|
||||
|
||||
Args:
|
||||
embed_dim (int): :math:`C_{in}` from an expected input of size :math:`(N, S, C_{in})`
|
||||
num_heads (int): Number of heads in multi-head attention
|
||||
attn_dropout (Optional[float]): Attention dropout. Default: 0.0
|
||||
bias (Optional[bool]): Use bias or not. Default: ``True``
|
||||
|
||||
Notes:
|
||||
- Input:
|
||||
- Query tensor (x_q) :math:`(N, S, C_{in})` where :math:`N` is batch size, :math:`S` is number of source tokens,
|
||||
and: math:`C_{in}` is input embedding dim
|
||||
- Optional Key-Value tensor (x_kv) :math:`(N, T, C_{in})` where :math:`T` is number of target tokens
|
||||
- Output: same shape as the input
|
||||
"""
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
embed_dim: int,
|
||||
num_heads: int,
|
||||
attn_dropout: float | None = 0.0,
|
||||
bias: bool | None = True,
|
||||
output_dim: int | None = None,
|
||||
*args,
|
||||
**kwargs,
|
||||
) -> None:
|
||||
if output_dim is None:
|
||||
output_dim = embed_dim
|
||||
super().__init__()
|
||||
if embed_dim % num_heads != 0:
|
||||
logger.error(
|
||||
f"Embedding dim must be divisible by number of heads in {self.__class__.__name__}. Got: embed_dim={embed_dim} and num_heads={num_heads}"
|
||||
)
|
||||
|
||||
self.qkv_proj = nn.Linear(in_features=embed_dim, out_features=3 * embed_dim, bias=bias)
|
||||
|
||||
self.attn_dropout = nn.Dropout(p=attn_dropout)
|
||||
self.out_proj = nn.Linear(in_features=embed_dim, out_features=output_dim, bias=bias)
|
||||
|
||||
self.head_dim = embed_dim // num_heads
|
||||
self.scaling = self.head_dim**-0.5
|
||||
self.softmax = nn.Softmax(dim=-1)
|
||||
self.num_heads = num_heads
|
||||
self.embed_dim = embed_dim
|
||||
self.use_separate_proj_weight = embed_dim != output_dim
|
||||
|
||||
def __repr__(self):
|
||||
return f"{self.__class__.__name__}(head_dim={self.head_dim}, num_heads={self.num_heads}, attn_dropout={self.attn_dropout.p})"
|
||||
|
||||
def _forward_impl(
|
||||
self,
|
||||
x_q: Tensor,
|
||||
x_kv: Tensor | None = None,
|
||||
key_padding_mask: Tensor | None = None,
|
||||
attn_mask: Tensor | None = None,
|
||||
) -> Tensor:
|
||||
# [N, S, C]
|
||||
b_sz, S_len, _in_channels = x_q.shape
|
||||
|
||||
if x_kv is None:
|
||||
# self-attention
|
||||
# [N, S, C] --> [N, S, 3C] --> [N, S, 3, h, c] where C = hc
|
||||
qkv = self.qkv_proj(x_q).reshape(b_sz, S_len, 3, self.num_heads, -1)
|
||||
# [N, S, 3, h, c] --> [N, h, 3, S, C]
|
||||
qkv = qkv.transpose(1, 3).contiguous()
|
||||
|
||||
# [N, h, 3, S, C] --> [N, h, S, C] x 3
|
||||
query, key, value = qkv[:, :, 0], qkv[:, :, 1], qkv[:, :, 2]
|
||||
else:
|
||||
T_len = x_kv.shape[1]
|
||||
|
||||
# cross-attention
|
||||
# [N, S, C]
|
||||
query = F.linear(
|
||||
x_q,
|
||||
weight=self.qkv_proj.weight[: self.embed_dim, ...],
|
||||
bias=self.qkv_proj.bias[: self.embed_dim] if self.qkv_proj.bias is not None else None,
|
||||
)
|
||||
# [N, S, C] --> [N, S, h, c] --> [N, h, S, c]
|
||||
query = query.reshape(b_sz, S_len, self.num_heads, self.head_dim).transpose(1, 2).contiguous()
|
||||
|
||||
# [N, T, C] --> [N, T, 2C]
|
||||
kv = F.linear(
|
||||
x_kv,
|
||||
weight=self.qkv_proj.weight[self.embed_dim :, ...],
|
||||
bias=self.qkv_proj.bias[self.embed_dim :] if self.qkv_proj.bias is not None else None,
|
||||
)
|
||||
# [N, T, 2C] --> [N, T, 2, h, c]
|
||||
kv = kv.reshape(b_sz, T_len, 2, self.num_heads, self.head_dim)
|
||||
# [N, T, 2, h, c] --> [N, h, 2, T, c]
|
||||
kv = kv.transpose(1, 3).contiguous()
|
||||
key, value = kv[:, :, 0], kv[:, :, 1]
|
||||
|
||||
query = query * self.scaling
|
||||
|
||||
# [N h, T, c] --> [N, h, c, T]
|
||||
key = key.transpose(-1, -2)
|
||||
|
||||
# QK^T
|
||||
# [N, h, S, c] x [N, h, c, T] --> [N, h, S, T]
|
||||
attn = torch.matmul(query, key)
|
||||
|
||||
batch_size, _num_heads, num_src_tokens, num_tgt_tokens = attn.shape
|
||||
if attn_mask is not None:
|
||||
# attn_mask shape should be the same as attn
|
||||
assert list(attn_mask.shape) == [
|
||||
batch_size,
|
||||
num_src_tokens,
|
||||
num_tgt_tokens,
|
||||
], (
|
||||
f"Shape of attention mask should be [{batch_size}, {num_src_tokens}, {num_tgt_tokens}]. Got: {attn_mask.shape}"
|
||||
)
|
||||
# [N, S, T] --> [N, 1, S, T]
|
||||
attn_mask = attn_mask.unsqueeze(1)
|
||||
attn = attn + attn_mask
|
||||
|
||||
if key_padding_mask is not None:
|
||||
# Do not attend to padding positions
|
||||
# key padding mask size is [N, T]
|
||||
assert key_padding_mask.dim() == 2 and list(key_padding_mask.shape) == [
|
||||
batch_size,
|
||||
num_tgt_tokens,
|
||||
], (
|
||||
f"Key_padding_mask should be 2-dimension with shape [{batch_size}, {num_tgt_tokens}]. Got: {key_padding_mask.shape}"
|
||||
)
|
||||
attn = attn.masked_fill(
|
||||
key_padding_mask.unsqueeze(1).unsqueeze(2).to(torch.bool), # [N, T] --> [N, 1, 1, T]
|
||||
float("-inf"),
|
||||
)
|
||||
|
||||
attn_dtype = attn.dtype
|
||||
attn_as_float = self.softmax(attn.float())
|
||||
attn = attn_as_float.to(attn_dtype)
|
||||
attn = self.attn_dropout(attn)
|
||||
|
||||
# weighted sum
|
||||
# [N, h, S, T] x [N, h, T, c] --> [N, h, S, c]
|
||||
out = torch.matmul(attn, value)
|
||||
|
||||
# [N, h, S, c] --> [N, S, h, c] --> [N, S, C]
|
||||
out = out.transpose(1, 2).reshape(b_sz, S_len, -1)
|
||||
out = self.out_proj(out)
|
||||
|
||||
return out
|
||||
|
||||
def forward(
|
||||
self,
|
||||
x_q: Tensor,
|
||||
x_kv: Tensor | None = None,
|
||||
key_padding_mask: Tensor | None = None,
|
||||
attn_mask: Tensor | None = None,
|
||||
*args,
|
||||
**kwargs,
|
||||
) -> Tensor:
|
||||
# [Batch , Sequence, Hidden_dim]
|
||||
return self._forward_impl(
|
||||
x_q=x_q,
|
||||
x_kv=x_kv,
|
||||
key_padding_mask=key_padding_mask,
|
||||
attn_mask=attn_mask,
|
||||
)
|
||||
|
||||
|
||||
class TransformerEncoder(nn.Module):
|
||||
"""This class defines the pre-norm `Transformer encoder <https://arxiv.org/abs/1706.03762>`_.
|
||||
|
||||
Args:
|
||||
embed_dim: :math:`C_{in}` from an expected input of size :math:`(N, P, C_{in})`.
|
||||
ffn_latent_dim: Inner dimension of the FFN.
|
||||
num_heads: Number of heads in multi-head attention. Default: 8.
|
||||
attn_dropout: Dropout rate for attention in multi-head attention. Default: 0.0
|
||||
dropout: Dropout rate. Default: 0.0.
|
||||
ffn_dropout: Dropout between FFN layers. Default: 0.0.
|
||||
transformer_norm_layer: Normalization layer. Default: layer_norm.
|
||||
stochastic_dropout: Stochastic dropout setting. Default: 0.0.
|
||||
|
||||
Notes:
|
||||
- Input: :math:`(N, P, C_{in})` where :math:`N` is batch size, :math:`P` is number of patches,
|
||||
and: math:`C_{in}` is input embedding dim
|
||||
- Output: same shape as the input
|
||||
"""
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
embed_dim: int,
|
||||
ffn_latent_dim: int,
|
||||
num_heads: int | None = 8,
|
||||
attn_dropout: float | None = 0.0,
|
||||
dropout: float | None = 0.0,
|
||||
ffn_dropout: float | None = 0.0,
|
||||
transformer_norm_layer: str | None = "layer_norm",
|
||||
stochastic_dropout: float | None = 0.0,
|
||||
*args,
|
||||
**kwargs,
|
||||
) -> None:
|
||||
super().__init__()
|
||||
|
||||
# Build attention layer
|
||||
attn_unit = MultiHeadAttention(
|
||||
embed_dim,
|
||||
num_heads,
|
||||
attn_dropout=attn_dropout,
|
||||
bias=True,
|
||||
)
|
||||
|
||||
self.pre_norm_mha = nn.Sequential(
|
||||
get_normalization_layer(norm_type=transformer_norm_layer, num_features=embed_dim),
|
||||
attn_unit,
|
||||
nn.Dropout(p=dropout),
|
||||
)
|
||||
|
||||
act_name = nn.GELU()
|
||||
self.pre_norm_ffn = nn.Sequential(
|
||||
get_normalization_layer(norm_type=transformer_norm_layer, num_features=embed_dim),
|
||||
nn.Linear(in_features=embed_dim, out_features=ffn_latent_dim, bias=True),
|
||||
act_name,
|
||||
nn.Dropout(p=ffn_dropout),
|
||||
nn.Linear(in_features=ffn_latent_dim, out_features=embed_dim, bias=True),
|
||||
nn.Dropout(p=dropout),
|
||||
)
|
||||
|
||||
self.drop_path = nn.Identity()
|
||||
if stochastic_dropout > 0.0:
|
||||
if dropout > 0.0:
|
||||
logger.error(
|
||||
"Stochastic dropout and dropout are mutually exclusive. "
|
||||
"Use either of them, but not both."
|
||||
f"Got: {stochastic_dropout} and {dropout}"
|
||||
)
|
||||
self.drop_path = StochasticDepth(p=stochastic_dropout, mode="row")
|
||||
|
||||
self.embed_dim = embed_dim
|
||||
self.ffn_dim = ffn_latent_dim
|
||||
self.ffn_dropout = ffn_dropout
|
||||
self.stochastic_dropout = stochastic_dropout
|
||||
self.std_dropout = dropout
|
||||
self.attn_fn_name = attn_unit.__class__.__name__
|
||||
self.act_fn_name = act_name.__class__.__name__
|
||||
self.norm_type = transformer_norm_layer
|
||||
|
||||
def __repr__(self) -> str:
|
||||
return f"{self.__class__.__name__}(embed_dim={self.embed_dim}, ffn_dim={self.ffn_dim}, dropout={self.std_dropout}, ffn_dropout={self.ffn_dropout}, stochastic_dropout={self.stochastic_dropout}, attn_fn={self.attn_fn_name}, act_fn={self.act_fn_name}, norm_fn={self.norm_type})"
|
||||
|
||||
def forward(
|
||||
self,
|
||||
x: Tensor,
|
||||
x_prev: Tensor | None = None,
|
||||
key_padding_mask: Tensor | None = None,
|
||||
attn_mask: Tensor | None = None,
|
||||
*args,
|
||||
**kwargs,
|
||||
) -> Tensor:
|
||||
# Multi-head attention
|
||||
res = x
|
||||
x = self.pre_norm_mha[0](x) # norm
|
||||
x = self.pre_norm_mha[1](
|
||||
x_q=x,
|
||||
x_kv=x_prev,
|
||||
key_padding_mask=key_padding_mask,
|
||||
attn_mask=attn_mask,
|
||||
*args,
|
||||
**kwargs,
|
||||
) # mha
|
||||
|
||||
x = self.drop_path(self.pre_norm_mha[2](x)) # applying stochastic depth
|
||||
x = x + res
|
||||
|
||||
# Feed forward network
|
||||
x = x + self.drop_path(self.pre_norm_ffn(x))
|
||||
return x
|
||||
Reference in New Issue
Block a user