Source code for flowvision.models.face_recognition.ir_resnet

"""
Modified from https://github.com/deepinsight/insightface/blob/master/recognition/arcface_torch/backbones/iresnet.py
"""

from typing import Type, Any, Callable, Union, List, Optional

import oneflow as flow
import oneflow.nn as nn

from ..utils import load_state_dict_from_url
from ..registry import ModelCreator

__all__ = [
    "iresnet50",
    "iresnet101",
]


model_urls = {
    "iresnet50": "https://oneflow-public.oss-cn-beijing.aliyuncs.com/model_zoo/flowvision/classification/IResnet/iresnet50.zip",
    "iresnet101": "https://oneflow-public.oss-cn-beijing.aliyuncs.com/model_zoo/flowvision/classification/IResnet/iresnet101.zip",
}


def conv3x3(
    in_planes: int, out_planes: int, stride: int = 1, groups: int = 1, dilation: int = 1
) -> nn.Conv2d:
    """3x3 convolution with padding"""
    return nn.Conv2d(
        in_planes,
        out_planes,
        kernel_size=3,
        stride=stride,
        padding=dilation,
        groups=groups,
        bias=False,
        dilation=dilation,
    )


def conv1x1(in_planes: int, out_planes: int, stride: int = 1) -> nn.Conv2d:
    """1x1 convolution"""
    return nn.Conv2d(in_planes, out_planes, kernel_size=1, stride=stride, bias=False)


class IBasicBlock(nn.Module):
    expansion = 1

    def __init__(
        self,
        inplanes,
        planes,
        stride=1,
        downsample=None,
        groups=1,
        base_width=64,
        dilation=1,
    ):
        super(IBasicBlock, self).__init__()
        if groups != 1 or base_width != 64:
            raise ValueError("BasicBlock only supports groups=1 and base_width=64")
        if dilation > 1:
            raise NotImplementedError("Dilation > 1 not supported in BasicBlock")
        self.bn1 = nn.BatchNorm2d(inplanes, eps=1e-05,)
        self.conv1 = conv3x3(inplanes, planes)
        self.bn2 = nn.BatchNorm2d(planes, eps=1e-05,)
        self.prelu = nn.ReLU(planes)
        self.conv2 = conv3x3(planes, planes, stride)
        self.bn3 = nn.BatchNorm2d(planes, eps=1e-05,)
        self.downsample = downsample
        self.stride = stride

    def forward(self, x):
        identity = x
        out = self.bn1(x)
        out = self.conv1(out)
        out = self.bn2(out)
        out = self.prelu(out)
        out = self.conv2(out)
        out = self.bn3(out)
        if self.downsample is not None:
            identity = self.downsample(x)
        out += identity
        return out


class IResNet(nn.Module):
    fc_scale = 7 * 7

    def __init__(
        self,
        block,
        layers,
        dropout=0,
        num_features=512,
        zero_init_residual=False,
        groups=1,
        width_per_group=64,
        replace_stride_with_dilation=None,
        fp16=False,
        channel_last=False,
    ):
        super(IResNet, self).__init__()
        self.fp16 = fp16
        self.inplanes = 64
        self.dilation = 1
        if replace_stride_with_dilation is None:
            replace_stride_with_dilation = [False, False, False]
        if len(replace_stride_with_dilation) != 3:
            raise ValueError(
                "replace_stride_with_dilation should be None "
                "or a 3-element tuple, got {}".format(replace_stride_with_dilation)
            )
        self.groups = groups
        self.base_width = width_per_group

        self.conv1 = nn.Conv2d(
            3, self.inplanes, kernel_size=3, stride=1, padding=1, bias=False
        )
        self.bn1 = nn.BatchNorm2d(self.inplanes, eps=1e-05)
        self.prelu = nn.ReLU(self.inplanes)
        self.layer1 = self._make_layer(block, 64, layers[0], stride=2)
        self.layer2 = self._make_layer(
            block, 128, layers[1], stride=2, dilate=replace_stride_with_dilation[0]
        )
        self.layer3 = self._make_layer(
            block, 256, layers[2], stride=2, dilate=replace_stride_with_dilation[1]
        )
        self.layer4 = self._make_layer(
            block, 512, layers[3], stride=2, dilate=replace_stride_with_dilation[2]
        )
        self.bn2 = nn.BatchNorm2d(512 * block.expansion, eps=1e-05,)
        self.dropout = nn.Dropout(p=dropout, inplace=True)
        self.fc = nn.Linear(512 * block.expansion * self.fc_scale, num_features)
        self.features = nn.BatchNorm1d(num_features, eps=1e-05)
        nn.init.constant_(self.features.weight, 1.0)
        self.features.weight.requires_grad = False

        for m in self.modules():
            if isinstance(m, nn.Conv2d):
                nn.init.normal_(m.weight, 0, 0.1)
            elif isinstance(m, (nn.BatchNorm2d, nn.GroupNorm)):
                nn.init.constant_(m.weight, 1)
                nn.init.constant_(m.bias, 0)

        if zero_init_residual:
            for m in self.modules():
                if isinstance(m, IBasicBlock):
                    nn.init.constant_(m.bn2.weight, 0)

    def _make_layer(self, block, planes, blocks, stride=1, dilate=False):
        downsample = None
        previous_dilation = self.dilation
        if dilate:
            self.dilation *= stride
            stride = 1
        if stride != 1 or self.inplanes != planes * block.expansion:
            downsample = nn.Sequential(
                conv1x1(self.inplanes, planes * block.expansion, stride),
                nn.BatchNorm2d(planes * block.expansion, eps=1e-05,),
            )
        layers = []
        layers.append(
            block(
                self.inplanes,
                planes,
                stride,
                downsample,
                self.groups,
                self.base_width,
                previous_dilation,
            )
        )
        self.inplanes = planes * block.expansion
        for _ in range(1, blocks):
            layers.append(
                block(
                    self.inplanes,
                    planes,
                    groups=self.groups,
                    base_width=self.base_width,
                    dilation=self.dilation,
                )
            )

        return nn.Sequential(*layers)

    def forward(self, x):
        x = self.conv1(x)
        x = self.bn1(x)
        x = self.prelu(x)
        x = self.layer1(x)
        x = self.layer2(x)
        x = self.layer3(x)
        x = self.layer4(x)
        x = self.bn2(x)
        x = flow.flatten(x, 1)
        x = self.dropout(x)
        x = self.fc(x)
        x = self.features(x)

        return x


def _iresnet(
    arch: str,
    block: Type[IBasicBlock],
    layers: List[int],
    pretrained: bool,
    progress: bool,
    **kwargs: Any
) -> IResNet:
    model = IResNet(block, layers, **kwargs)
    if pretrained:
        state_dict = load_state_dict_from_url(model_urls[arch], progress=progress)
        model.load_state_dict(state_dict)
    return model


[docs]@ModelCreator.register_model def iresnet50(pretrained=False, progress=True, **kwargs): """ Constructs the IResNet-50 model trained on webface600K(https://www.face-benchmark.org/download.html). .. note:: The required input size of the model is 112x112. Args: pretrained (bool): Whether to download the pre-trained model on webface600K. Default: ``False`` progress (bool): If True, displays a progress bar of the download to stderr. Default: ``True`` For example: .. code-block:: python >>> import flowvision >>> iresnet50 = flowvision.models.face_recognition.iresnet50(pretrained=False, progress=True) """ return _iresnet( "iresnet50", IBasicBlock, [3, 4, 14, 3], pretrained, progress, **kwargs )
[docs]@ModelCreator.register_model def iresnet101(pretrained=False, progress=True, **kwargs): """ Constructs the IResNet-101 model trained on Glint360K(https://github.com/deepinsight/insightface/tree/master/recognition/partial_fc#4-download). .. note:: The required input size of the model is 112x112. Args: pretrained (bool): Whether to download the pre-trained model on Glint360K. Default: ``False`` progress (bool): If True, displays a progress bar of the download to stderr. Default: ``True`` For example: .. code-block:: python >>> import flowvision >>> iresnet101 = flowvision.models.face_recognition.iresnet101(pretrained=False, progress=True) """ return _iresnet( "iresnet101", IBasicBlock, [3, 13, 30, 3], pretrained, progress, **kwargs )