Class ResNet

pycontrast/networks/resnest.py:198–373

ResNet Variants Parameters ---------- block : Block Class for the residual block. Options are BasicBlockV1, BottleneckV1. layers : list of int Numbers of layers in each block classes : int, default 1000 Number of classification classes. dilated : bool,

class ResNet(nn.Module):
    """ResNet Variants
    Parameters
    ----------
    block : Block
        Class for the residual block. Options are BasicBlockV1, BottleneckV1.
    layers : list of int
        Numbers of layers in each block
    classes : int, default 1000
        Number of classification classes.
    dilated : bool, default False
        Applying dilation strategy to pretrained ResNet yielding a stride-8 model,
        typically used in Semantic Segmentation.
    norm_layer : object
        Normalization layer used in backbone network (default: :class:`mxnet.gluon.nn.BatchNorm`;
        for Synchronized Cross-GPU BachNormalization).
    Reference:
        - He, Kaiming, et al. "Deep residual learning for image recognition." Proceedings of the IEEE conference on computer vision and pattern recognition. 2016.
        - Yu, Fisher, and Vladlen Koltun. "Multi-scale context aggregation by dilated convolutions."
    """
    # pylint: disable=unused-variable
    def __init__(self, block, layers, radix=1, groups=1, bottleneck_width=64,
                 num_classes=1000, dilated=False, dilation=1,
                 deep_stem=False, stem_width=64, avg_down=False,
                 rectified_conv=False, rectify_avg=False,
                 avd=False, avd_first=False,
                 final_drop=0.0, dropblock_prob=0,
                 last_gamma=False, norm_layer=nn.BatchNorm2d,
                 width=1, in_channel=3):
        self.cardinality = groups
        self.bottleneck_width = bottleneck_width
        # ResNet-D params
        self.inplanes = stem_width*2 if deep_stem else max(int(64 * width), 64)
        self.base = int(64 * width)
        self.avg_down = avg_down
        self.last_gamma = last_gamma
        # ResNeSt params
        self.radix = radix
        self.avd = avd
        self.avd_first = avd_first

        super(ResNet, self).__init__()
        self.rectified_conv = rectified_conv
        self.rectify_avg = rectify_avg
        if rectified_conv:
            from rfconv import RFConv2d
            conv_layer = RFConv2d
        else:
            conv_layer = nn.Conv2d
        conv_kwargs = {'average_mode': rectify_avg} if rectified_conv else {}
        if deep_stem:
            self.conv1 = nn.Sequential(
                conv_layer(in_channel, stem_width, kernel_size=3, stride=2, padding=1, bias=False, **conv_kwargs),
                norm_layer(stem_width),
                nn.ReLU(inplace=True),
                conv_layer(stem_width, stem_width, kernel_size=3, stride=1, padding=1, bias=False, **conv_kwargs),
                norm_layer(stem_width),
                nn.ReLU(inplace=True),