hello everyone. I am new to Pytorch, sorry if my question is too simple. I found this code on Github for implementing U-Net architecture. I don’t understand what is “bridge” for in the forward method. could anybody explain it to me please?
def center_crop(self, layer, target_size):
_, _, layer_height, layer_width = layer.size()
diff_y = (layer_height - target_size[0]) // 2
diff_x = (layer_width - target_size[1]) // 2
return layer[
:, :, diff_y : (diff_y + target_size[0]), diff_x : (diff_x + target_size[1])
]
def forward(self, x, bridge):
    up = self.up(x)
    crop1 = self.center_crop(bridge, up.shape[2:])
    out = torch.cat([up, crop1], 1)
    out = self.conv_block(out)

    return out