From bf806a987faa575e3643a456bb80c1aa3ee21575 Mon Sep 17 00:00:00 2001
From: KaiyangZhou <k.zhou@qmul.ac.uk>
Date: Sat, 28 Apr 2018 10:55:49 +0100
Subject: [PATCH] add vanilla squeezenet

---
 models/SqueezeNet.py | 92 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 92 insertions(+)
 create mode 100644 models/SqueezeNet.py

diff --git a/models/SqueezeNet.py b/models/SqueezeNet.py
new file mode 100644
index 0000000..3930fe4
--- /dev/null
+++ b/models/SqueezeNet.py
@@ -0,0 +1,92 @@
+from __future__ import absolute_import
+
+import torch
+from torch import nn
+from torch.nn import functional as F
+import torchvision
+
+__all__ = ['SqueezeNet']
+
+class ConvBlock(nn.Module):
+    """Basic convolutional block:
+    convolution + batch normalization + relu.
+
+    Args (following http://pytorch.org/docs/master/nn.html#torch.nn.Conv2d):
+        in_c (int): number of input channels.
+        out_c (int): number of output channels.
+        k (int or tuple): kernel size.
+        s (int or tuple): stride.
+        p (int or tuple): padding.
+    """
+    def __init__(self, in_c, out_c, k, s=1, p=0):
+        super(ConvBlock, self).__init__()
+        self.conv = nn.Conv2d(in_c, out_c, k, stride=s, padding=p)
+        self.bn = nn.BatchNorm2d(out_c)
+
+    def forward(self, x):
+        return F.relu(self.bn(self.conv(x)))
+
+class ExpandLayer(nn.Module):
+    def __init__(self, in_channels, e1_channels, e3_channels):
+        super(ExpandLayer, self).__init__()
+        self.conv11 = ConvBlock(in_channels, e1_channels, 1)
+        self.conv33 = ConvBlock(in_channels, e3_channels, 3, p=1)
+
+    def forward(self, x):
+        x11 = self.conv11(x)
+        x33 = self.conv33(x)
+        x = torch.cat([x11, x33], 1)
+        return x
+
+class FireModule(nn.Module):
+    """Fire Module"""
+    def __init__(self, in_channels, s1_channels, e1_channels, e3_channels):
+        super(FireModule, self).__init__()
+        self.squeeze = ConvBlock(in_channels, s1_channels, 1)
+        self.expand = ExpandLayer(s1_channels, e1_channels, e3_channels)
+
+    def forward(self, x):
+        x = self.squeeze(x)
+        x = self.expand(x)
+        return x
+
+class SqueezeNet(nn.Module):
+    def __init__(self, num_classes, loss={'xent'}, **kwargs):
+        super(SqueezeNet, self).__init__()
+        self.loss = loss
+
+        self.conv1 = ConvBlock(3, 96, 7, s=2, p=2)
+        self.fire2 = FireModule(96, 16, 64, 64)
+        self.fire3 = FireModule(128, 16, 64, 64)
+        self.fire4 = FireModule(128, 32, 128, 128)
+        self.fire5 = FireModule(256, 32, 128, 128)
+        self.fire6 = FireModule(256, 48, 192, 192)
+        self.fire7 = FireModule(384, 48, 192, 192)
+        self.fire8 = FireModule(384, 64, 256, 256)
+        self.fire9 = FireModule(512, 64, 256, 256)
+        self.conv10 = ConvBlock(512, 1000, 1)
+
+    def forward(self, x):
+        x = self.conv1(x)
+        x = F.max_pool2d(x, 3, stride=2)
+        x = self.fire2(x)
+        x = self.fire3(x)
+        x = self.fire4(x)
+        x = F.max_pool2d(x, 3, stride=2)
+        x = self.fire5(x)
+        x = self.fire6(x)
+        x = self.fire7(x)
+        x = self.fire8(x)
+        x = F.max_pool2d(x, 3, stride=2)
+        x = self.fire9(x)
+        x = self.conv10(x)
+        x = F.avg_pool2d(x, x.size()[2:])
+        return x
+
+if __name__ == '__main__':
+    model = SqueezeNet(10)
+    model.eval()
+    x = torch.rand(1, 3, 256, 128)
+    with torch.no_grad():
+        y = model(x)
+        print "output size {}".format(y.size())
\ No newline at end of file